#include "pgroonga.h"

#include "pgrn-compatible.h"

#include "pgrn-alias.h"
#include "pgrn-auto-close.h"
#include "pgrn-command-escape-value.h"
#include "pgrn-condition.h"
#include "pgrn-convert.h"
#include "pgrn-crash-safer-statuses.h"
#include "pgrn-create.h"
#include "pgrn-ctid.h"
#include "pgrn-custom-scan.h"
#include "pgrn-file.h"
#include "pgrn-global.h"
#include "pgrn-groonga-tuple-is-alive.h"
#include "pgrn-groonga.h"
#include "pgrn-highlight-html.h"
#include "pgrn-index-status.h"
#include "pgrn-jsonb.h"
#include "pgrn-keywords.h"
#include "pgrn-language-model-vectorize.h"
#include "pgrn-match-positions-byte.h"
#include "pgrn-match-positions-character.h"
#include "pgrn-normalize.h"
#include "pgrn-options.h"
#include "pgrn-pg.h"
#include "pgrn-portable.h"
#include "pgrn-query-expand.h"
#include "pgrn-query-extract-keywords.h"
#include "pgrn-row-level-security.h"
#include "pgrn-search.h"
#include "pgrn-sequential-search.h"
#include "pgrn-string.h"
#include "pgrn-tokenize.h"
#include "pgrn-trace-log.h"
#include "pgrn-value.h"
#include "pgrn-variables.h"
#include "pgrn-wal.h"
#include "pgrn-writable.h"

#include <access/amapi.h>
#include <access/reloptions.h>
#include <access/relscan.h>
#include <access/table.h>
#include <access/tableam.h>
#include <access/xlog_internal.h>
#include <catalog/catalog.h>
#include <catalog/index.h>
#include <catalog/pg_type.h>
#include <commands/progress.h>
#include <commands/vacuum.h>
#include <executor/instrument.h>
#include <mb/pg_wchar.h>
#include <miscadmin.h>
#include <nodes/nodeFuncs.h>
#include <optimizer/optimizer.h>
#include <pgstat.h>
#include <storage/bufmgr.h>
#include <storage/condition_variable.h>
#include <storage/ipc.h>
#include <storage/latch.h>
#include <storage/shm_toc.h>
#include <storage/smgr.h>
#include <tcop/tcopprot.h>
#include <utils/array.h>
#include <utils/builtins.h>
#include <utils/lsyscache.h>
#include <utils/memutils.h>
#include <utils/rel.h>
#include <utils/selfuncs.h>
#include <utils/snapmgr.h>
#include <utils/timestamp.h>
#include <utils/typcache.h>
#include <utils/wait_event.h>

#include <lib/ilist.h>

#include <groonga.h>

#include <math.h>
#include <stdlib.h>
#include <string.h>

PG_MODULE_MAGIC;

#define PROGRESS_PGROONGA_PHASE_IMPORT 2
#define PROGRESS_PGROONGA_PHASE_INDEX 3
#define PROGRESS_PGROONGA_PHASE_INDEX_LOAD 4
#define PROGRESS_PGROONGA_PHASE_INDEX_COMMIT 5
#define PROGRESS_PGROONGA_PHASE_DONE 6
#define PROGRESS_PGROONGA_PHASE_INDEX_VECTORIZE 7
#define PROGRESS_PGROONGA_PHASE_INDEX_CLUSTER 8

grn_ctx PGrnContext;
grn_obj PGrnInspectBuffer;
static bool PGrnInitialized = false;
static bool PGrnBaseInitialized = false;
bool PGrnGroongaInitialized = false;
static bool PGrnCrashSaferInitialized = false;
bool PGrnEnableParallelBuildCopy = false;

typedef struct PGrnProcessSharedData
{
	TimestampTz lastVacuumTimestamp;
} PGrnProcessSharedData;

typedef struct PGrnProcessLocalData
{
	TimestampTz lastDBUnmapTimestamp;
} PGrnProcessLocalData;

static PGrnProcessSharedData *processSharedData = NULL;
static PGrnProcessLocalData processLocalData;

typedef struct PGrnBuildStateData
{
	grn_obj *sourcesTable;
	grn_obj *sourcesCtidColumn;
	double nProcessedHeapTuples;
	double nIndexedTuples;
	bool needMaxRecordSizeUpdate;
	uint32_t maxRecordSize;
	MemoryContext memoryContext;
	PGrnWALData *bulkInsertWALData;
	bool isBulkInsert;
	grn_wal_role walRoleKeep;
} PGrnBuildStateData;

typedef PGrnBuildStateData *PGrnBuildState;

typedef struct PGrnPrimaryKeyColumn
{
	slist_node node;
	AttrNumber number;
	Oid type;
	grn_id domain;
	unsigned char flags;
	grn_obj *column;
} PGrnPrimaryKeyColumn;

typedef struct PGrnScanOpaqueData
{
	Relation index;

	MemoryContext memoryContext;

	Oid dataTableID;
	grn_obj *sourcesTable;
	grn_obj *sourcesCtidColumn;
	grn_obj *ctidResolveTable;
	grn_obj minBorderValue;
	grn_obj maxBorderValue;
	grn_obj *searched;
	grn_obj *sorted;
	grn_obj *targetTable;
	grn_obj *indexCursor;
	grn_table_cursor *tableCursor;
	grn_obj *ctidAccessor;
	grn_obj *scoreAccessor;
	grn_id currentID;

	grn_obj canReturns;

	dlist_node node;
	slist_head primaryKeyColumns;
	grn_obj *scoreTargetRecords;
} PGrnScanOpaqueData;

typedef PGrnScanOpaqueData *PGrnScanOpaque;

typedef struct PGrnPrefixRKSequentialSearchData
{
	grn_obj *table;
	grn_obj *key;
	grn_obj *resultTable;
} PGrnPrefixRKSequentialSearchData;

typedef struct PGrnParallelScanDescData
{
	slock_t mutex;
	bool scanning;
} PGrnParallelScanDescData;
typedef PGrnParallelScanDescData *PGrnParallelScanDesc;

static bool PGrnParallelScanAcquire(IndexScanDesc scan);

static dlist_head PGrnScanOpaques = DLIST_STATIC_INIT(PGrnScanOpaques);
static unsigned int PGrnNScanOpaques = 0;

extern PGDLLEXPORT void _PG_init(void);

PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_score);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_score_row);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_score_ctid);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_table_name);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_command);

/*
 * Naming conversions:
 *
 *   * pgroonga_#{operation}_#{type}(operand1 #{type}, operand2 #{type})
 *     * e.g.: pgroonga_match_text(target text, term text)
 *     * true when #{operand1} #{operation} #{operand2} is true,
 *       false otherwise.
 *     * e.g.: "PGroonga is great" match "great" -> true
 *
 *   * pgroonga_#{operation}_#{type}_array(operands1 #{type}[],
 *                                         operand2 #{type})
 *     * e.g.: pgroonga_match_text_array(targets text[], term text)
 *     * true when #{one of operands1} #{operation} #{operand2} is true,
 *       false otherwise.
 *     * e.g.: ["PGroonga is great", "PostgreSQL is great"] match "PGroonga"
 *       -> true
 *
 *   * pgroonga_#{operation}_in_#{type}(operand1 #{type}, operands2 #{type}[])
 *     * e.g.: pgroonga_match_in_text(target text, terms text[])
 *     * true when #{operand1} #{operation} #{one of operands2} is true,
 *       false otherwise.
 *     * e.g.: "PGroonga is great" match ["PGroonga", "PostgreSQL"]
 *       -> true
 *
 *   * pgroonga_#{operation}_in_#{type}_array(operands1 #{type}[],
 *                                            operands2 #{type}[])
 *     * e.g.: pgroonga_match_in_text_array(targets1 text[], terms2 text[])
 *     * true when #{one of operands1} #{operation} #{one of operands2} is true,
 *       false otherwise.
 *     * e.g.: ["PGroonga is great", "PostgreSQL is great"] match
 *       ["Groonga", "PostgreSQL"] -> true
 */

PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_match_term_text);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_match_term_text_array);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_match_term_varchar);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_match_term_varchar_array);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_match_query_text);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_match_query_text_array);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_match_query_varchar);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_match_regexp_text);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_match_regexp_varchar);

/* v2 */
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_match_text);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_match_text_condition);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_match_text_condition_with_scorers);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_match_text_array);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_match_text_array_condition);
PGDLLEXPORT
PG_FUNCTION_INFO_V1(pgroonga_match_text_array_condition_with_scorers);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_match_varchar);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_match_varchar_condition);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_match_varchar_condition_with_scorers);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_contain_varchar_array);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_query_text);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_query_text_condition);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_query_text_condition_with_scorers);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_query_text_array);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_query_text_array_condition);
PGDLLEXPORT
PG_FUNCTION_INFO_V1(pgroonga_query_text_array_condition_with_scorers);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_query_varchar);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_query_varchar_condition);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_query_varchar_condition_with_scorers);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_similar_text);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_similar_text_array);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_similar_varchar);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_similar_text_condition);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_similar_distance_text_condition);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_script_text);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_script_text_array);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_script_varchar);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_prefix_text);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_prefix_text_condition);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_prefix_text_array);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_prefix_text_array_condition);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_prefix_varchar);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_prefix_varchar_condition);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_prefix_varchar_array);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_prefix_varchar_array_condition);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_prefix_contain_text_array);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_prefix_rk_text);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_prefix_rk_text_array);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_prefix_rk_varchar);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_prefix_rk_varchar_array);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_prefix_rk_contain_text_array);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_match_in_text);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_match_contain_text);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_match_in_text_array);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_match_in_varchar);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_query_in_text);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_query_contain_text);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_query_in_text_array);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_query_in_varchar);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_prefix_in_text);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_not_prefix_in_text);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_prefix_in_text_array);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_prefix_in_varchar);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_prefix_in_varchar_array);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_prefix_rk_in_text);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_prefix_rk_in_text_array);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_prefix_rk_in_varchar);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_prefix_rk_in_varchar_array);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_regexp_text);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_regexp_text_array);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_regexp_text_array_condition);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_regexp_varchar);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_regexp_in_text);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_regexp_in_varchar);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_equal_text);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_equal_text_condition);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_equal_varchar);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_equal_varchar_condition);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_equal_query_text_array);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_equal_query_text_array_condition);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_equal_query_varchar_array);
PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_equal_query_varchar_array_condition);

PGDLLEXPORT PG_FUNCTION_INFO_V1(pgroonga_handler);

static struct PGrnBuffers *buffers = &PGrnBuffers;
static PGrnPrefixRKSequentialSearchData prefixRKSequentialSearchData;

static uint32_t
PGrnGetThreadLimit(void *data)
{
	return 1;
}

static grn_encoding
PGrnGetEncoding(void)
{
	return PGrnPGEncodingToGrnEncoding(GetDatabaseEncoding());
}

static void PGrnScanOpaqueFin(PGrnScanOpaque so);

static void
PGrnFinalizeScanOpaques(void)
{
	dlist_mutable_iter iter;
	dlist_foreach_modify(iter, &PGrnScanOpaques)
	{
		PGrnScanOpaque so;
		so = dlist_container(PGrnScanOpaqueData, node, iter.cur);
		PGrnScanOpaqueFin(so);
	}
}

static void
PGrnReleaseScanOpaques(ResourceReleasePhase phase,
					   bool isCommit,
					   bool isTopLevel,
					   void *arg)
{
	const char *tag = "pgroonga: [release][scan-opaques]";
	const char *top_level_tag = isTopLevel ? "[top-level]" : "";

	switch (phase)
	{
	case RESOURCE_RELEASE_BEFORE_LOCKS:
		GRN_LOG(ctx,
				GRN_LOG_DEBUG,
				"%s%s%s %u: skip",
				tag,
				top_level_tag,
				"[before-locks]",
				PGrnNScanOpaques);
		return;
	case RESOURCE_RELEASE_LOCKS:
		GRN_LOG(ctx,
				GRN_LOG_DEBUG,
				"%s%s%s %u: skip",
				tag,
				top_level_tag,
				"[locks]",
				PGrnNScanOpaques);
		return;
	case RESOURCE_RELEASE_AFTER_LOCKS:
		GRN_LOG(ctx,
				GRN_LOG_DEBUG,
				"%s%s%s[start] %u",
				tag,
				top_level_tag,
				"[after-locks]",
				PGrnNScanOpaques);
		if (!isTopLevel)
			return;
		break;
	}

	PGrnFinalizeScanOpaques();

	GRN_LOG(ctx,
			GRN_LOG_DEBUG,
			"%s%s%s[end] %u",
			tag,
			top_level_tag,
			"[after-locks]",
			PGrnNScanOpaques);
}

static void
PGrnInitializeGroongaFunctions(void)
{
	PGrnInitializeGroongaTupleIsAlive();
}

static void
PGrnFinalizePrefixRKSequentialSearchData(void)
{
	grn_obj_close(ctx, prefixRKSequentialSearchData.resultTable);
	grn_obj_close(ctx, prefixRKSequentialSearchData.key);
	grn_obj_close(ctx, prefixRKSequentialSearchData.table);
}

static void
PGrnBeforeShmemExit(int code, Datum arg)
{
	const char *tag = "pgroonga: [exit]";

	UnregisterResourceReleaseCallback(PGrnReleaseScanOpaques, NULL);
	UnregisterResourceReleaseCallback(PGrnReleaseSequentialSearch, NULL);

	if (ctx)
	{
		grn_obj *db;

		db = grn_ctx_db(ctx);
		GRN_LOG(ctx,
				GRN_LOG_DEBUG,
				"%s[db][%s]",
				tag,
				db ? "opened" : "not-opened");
		if (db)
		{
			GRN_LOG(ctx, GRN_LOG_DEBUG, "%s[finalize][scan-opaques]", tag);
			PGrnFinalizeScanOpaques();

			GRN_LOG(ctx, GRN_LOG_DEBUG, "%s[finalize][auto-close]", tag);
			PGrnFinalizeAutoClose();

			GRN_LOG(ctx,
					GRN_LOG_DEBUG,
					"%s[finalize][language-model-vectorize]",
					tag);
			PGrnFinalizeLanguageModelVectorize();

			GRN_LOG(ctx, GRN_LOG_DEBUG, "%s[finalize][normalize]", tag);
			PGrnFinalizeNormalize();

			GRN_LOG(ctx, GRN_LOG_DEBUG, "%s[finalize][tokenize]", tag);
			PGrnFinalizeTokenize();

			GRN_LOG(ctx,
					GRN_LOG_DEBUG,
					"%s[finalize][query-extract-keywords]",
					tag);
			PGrnFinalizeQueryExtractKeywords();

			GRN_LOG(
				ctx, GRN_LOG_DEBUG, "%s[finalize][match-positions-byte]", tag);
			PGrnFinalizeMatchPositionsByte();
			GRN_LOG(ctx,
					GRN_LOG_DEBUG,
					"%s[finalize][match-positions-character]",
					tag);
			PGrnFinalizeMatchPositionsCharacter();

			GRN_LOG(ctx, GRN_LOG_DEBUG, "%s[finalize][highlight-html]", tag);
			PGrnFinalizeHighlightHTML();

			GRN_LOG(ctx, GRN_LOG_DEBUG, "%s[finalize][keywords]", tag);
			PGrnFinalizeKeywords();

			GRN_LOG(ctx, GRN_LOG_DEBUG, "%s[finalize][jsonb]", tag);
			PGrnFinalizeJSONB();

			GRN_LOG(ctx,
					GRN_LOG_DEBUG,
					"%s[finalize][sequential-search-data]",
					tag);
			PGrnFinalizeSequentialSearch();
			GRN_LOG(ctx,
					GRN_LOG_DEBUG,
					"%s[finalize][prefix-rk-sequential-search-data]",
					tag);
			PGrnFinalizePrefixRKSequentialSearchData();

			GRN_LOG(ctx, GRN_LOG_DEBUG, "%s[finalize][options]", tag);
			PGrnFinalizeOptions();

			GRN_LOG(ctx, GRN_LOG_DEBUG, "%s[finalize][custom-scan]", tag);
			PGrnFinalizeCustomScan();

			GRN_LOG(ctx, GRN_LOG_DEBUG, "%s[db][close]", tag);
			grn_obj_close(ctx, db);
		}

		if (PGrnCrashSaferInitialized)
		{
			GRN_LOG(
				ctx, GRN_LOG_DEBUG, "%s[finalize][crash-safer][release]", tag);
			pgrn_crash_safer_statuses_release(
				NULL, MyDatabaseId, MyDatabaseTableSpace);
			PGrnCrashSaferInitialized = false;
		}

		GRN_LOG(ctx, GRN_LOG_DEBUG, "%s[finalize][buffers]", tag);
		PGrnFinalizeBuffers();

		GRN_OBJ_FIN(ctx, &PGrnInspectBuffer);

		GRN_LOG(ctx, GRN_LOG_DEBUG, "%s[finalize][context]", tag);
		grn_ctx_fin(ctx);
	}

	GRN_LOG(ctx, GRN_LOG_DEBUG, "%s[finalize]", tag);
#ifdef _WIN32
	pgwin32_install_crashdump_handler();
#else
#	ifdef SIGSEGV
	pqsignal(SIGSEGV, PGRN_SIG_DFL);
#	endif
#endif
#ifdef SIGABRT
	pqsignal(SIGABRT, PGRN_SIG_DFL);
#endif
	grn_fin();

	PGrnGroongaInitialized = false;
	PGrnBaseInitialized = false;
	PGrnInitialized = false;
}

static void
PGrnInitializePrefixRKSequentialSearchData(void)
{
	prefixRKSequentialSearchData.table =
		grn_table_create(ctx,
						 NULL,
						 0,
						 NULL,
						 GRN_OBJ_TABLE_PAT_KEY,
						 grn_ctx_at(ctx, GRN_DB_SHORT_TEXT),
						 NULL);

	prefixRKSequentialSearchData.key =
		grn_obj_column(ctx,
					   prefixRKSequentialSearchData.table,
					   GRN_COLUMN_NAME_KEY,
					   GRN_COLUMN_NAME_KEY_LEN);

	prefixRKSequentialSearchData.resultTable =
		grn_table_create(ctx,
						 NULL,
						 0,
						 NULL,
						 GRN_OBJ_TABLE_HASH_KEY | GRN_OBJ_WITH_SUBREC,
						 prefixRKSequentialSearchData.table,
						 NULL);
}

static void
PGrnInitializeDatabase(void)
{
	PGrnInitializeGroongaFunctions();

	PGrnInitializeAlias();

	PGrnInitializeIndexStatus();

	PGrnInitializeSequentialSearch();
	PGrnInitializePrefixRKSequentialSearchData();

	PGrnInitializeJSONB();

	PGrnInitializeKeywords();

	PGrnInitializeHighlightHTML();

	PGrnInitializeMatchPositionsByte();
	PGrnInitializeMatchPositionsCharacter();

	PGrnInitializeQueryExpand();

	PGrnInitializeQueryExtractKeywords();

	PGrnInitializeTokenize();

	PGrnInitializeNormalize();

	PGrnInitializeLanguageModelVectorize();

	PGrnInitializeAutoClose();
}

void
PGrnEnsureDatabase(void)
{
	char *databasePath;
	char path[MAXPGPATH];

	if (grn_ctx_db(ctx))
		return;

	if (!OidIsValid(MyDatabaseId))
		return;

	GRN_CTX_SET_ENCODING(ctx, PGrnGetEncoding());
	databasePath = GetDatabasePath(MyDatabaseId, MyDatabaseTableSpace);
	join_path_components(path, databasePath, PGrnDatabaseBasename);
	pfree(databasePath);

	if (grn_ctx_get_wal_role(ctx) == GRN_WAL_ROLE_SECONDARY &&
		!PGrnWALResourceManagerGetEnabled())
	{
		HTAB *statuses;
		pid_t crashSaferPID;
		pid_t preparePID;
		bool waitFlushing = true;

		statuses = pgrn_crash_safer_statuses_get();
		crashSaferPID = pgrn_crash_safer_statuses_get_main_pid(statuses);
		if (crashSaferPID == InvalidPid)
		{
			ereport(ERROR,
					(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
					 errmsg("pgroonga: "
							"pgroonga_crash_safer process doesn't exist: "
							"shared_preload_libraries may not include "
							"pgroonga_crash_safer")));
		}
		pgrn_crash_safer_statuses_use(
			statuses, MyDatabaseId, MyDatabaseTableSpace);
		PGrnCrashSaferInitialized = true;

		preparePID = pgrn_crash_safer_statuses_get_prepare_pid(
			statuses, MyDatabaseId, MyDatabaseTableSpace);
		if (preparePID == MyProcPid)
		{
			waitFlushing = false;
		}

		while (waitFlushing)
		{
			int conditions;
			long timeout = 1000;

			/* We need to reject any connections while preparing. If
			 * we accept a new connection and block the connection
			 * here, REINDEX by pgroonga-crash-safer may be blocked by
			 * the connection. */
			if (pgrn_crash_safer_statuses_is_preparing(
					statuses, MyDatabaseId, MyDatabaseTableSpace))
			{
				ereport(ERROR,
						(errcode(ERRCODE_CANNOT_CONNECT_NOW),
						 errmsg("pgroonga: "
								"pgroonga_crash_safer is preparing")));
			}

			if (pgrn_crash_safer_statuses_is_flushing(
					statuses, MyDatabaseId, MyDatabaseTableSpace))
			{
				break;
			}

			kill(crashSaferPID, SIGUSR1);

			conditions =
				WaitLatch(MyLatch,
						  WL_LATCH_SET | WL_TIMEOUT | WL_EXIT_ON_PM_DEATH,
						  timeout,
						  PG_WAIT_EXTENSION);
			if (conditions & WL_LATCH_SET)
			{
				ResetLatch(MyLatch);
			}
			CHECK_FOR_INTERRUPTS();
		}
	}

	if (pgrn_file_exist(path))
	{
		grn_db_open(ctx, path);
		PGrnCheck("failed to open database: <%s>", path);
	}
	else
	{
		grn_db_create(ctx, path, NULL);
		PGrnCheck("failed to create database: <%s>", path);
	}

	PGrnInitializeDatabase();
}

void
_PG_init(void)
{
	grn_rc rc;

	if (!PGrnInitialized)
	{
		PGrnInitialized = true;
		PGrnBaseInitialized = false;
		PGrnGroongaInitialized = false;

		PGrnInitializeVariables();

		grn_thread_set_get_limit_func(PGrnGetThreadLimit, NULL);

		grn_default_logger_set_flags(grn_default_logger_get_flags() |
									 GRN_LOG_PID);

		rc = grn_init();
		PGrnCheckRC(rc, "failed to initialize Groonga");

		grn_set_segv_handler();
		grn_set_abrt_handler();

		if (IsUnderPostmaster)
		{
			bool found;
			LWLockAcquire(AddinShmemInitLock, LW_EXCLUSIVE);
			processSharedData = (PGrnProcessSharedData *) ShmemInitStruct(
				"PGrnProcessSharedData", sizeof(PGrnProcessSharedData), &found);
			if (!found)
			{
				processSharedData->lastVacuumTimestamp = GetCurrentTimestamp();
			}
			LWLockRelease(AddinShmemInitLock);
		}
		processLocalData.lastDBUnmapTimestamp = GetCurrentTimestamp();

		before_shmem_exit(PGrnBeforeShmemExit, 0);

		RegisterResourceReleaseCallback(PGrnReleaseScanOpaques, NULL);
		RegisterResourceReleaseCallback(PGrnReleaseSequentialSearch, NULL);

		grn_set_default_match_escalation_threshold(
			PGrnMatchEscalationThreshold);

		rc = grn_ctx_init(ctx, 0);
		PGrnCheckRC(rc, "failed to initialize Groonga context");

		PGrnGroongaInitialized = true;

		GRN_LOG(
			ctx, GRN_LOG_NOTICE, "pgroonga: initialize: <%s>", PGRN_VERSION);

		GRN_TEXT_INIT(&PGrnInspectBuffer, 0);

		PGrnInitializeBuffers();

		PGrnInitializeGroongaInformation();

		PGrnVariablesApplyInitialValues();

		PGrnInitializeCustomScan();

		/* PGrnInitializeOptions() may use Groonga DB. */
		PGrnEnsureDatabase();

		PGrnInitializeOptions();

		PGrnBaseInitialized = true;
	}

	if (!PGrnBaseInitialized)
		PGrnCheckRC(GRN_UNKNOWN_ERROR,
					"already tried to initialize and failed");

	PGrnEnsureDatabase();
}

static void
PGrnUnmapDB(void)
{
	PGRN_TRACE_LOG_ENTER();

	PGrnFinalizeSequentialSearch();
	PGrnFinalizeHighlightHTML();

	grn_db_unmap(ctx, grn_ctx_db(ctx));

	PGrnInitializeSequentialSearch();
	PGrnInitializeHighlightHTML();

	PGRN_TRACE_LOG_EXIT();
}

/* We need to close opened grn_objs after VACUUM. Because VACUUM may
 * remove opened but unused grn_objs. If we use a removed grn_obj, the
 * process will be crashed. This closes opened grn_objs only after
 * VACUUM.
 *
 * This should not be called in the following functions:
 *
 *   * pgroonga_beginscan()
 *   * pgroonga_endscan()
 *   * pgroonga_rescan()
 *   * pgroonga_getbitmap()
 *   * pgroonga_gettuple()
 *
 * They use PGrnScanOpaques and a PGrnScanOpaque refers grn_obj. This
 * may close grn_obj referred by PGrnScanOpaque. We may have multiple
 * PGrnScanOpaques at the same time. We don't want to re-open all
 * grn_objs referred by all living PGrnScanOpaques after we close
 * grn_obj after VACUUM. So we should not call this in them.
 *
 * We can call this from pgroonga_costestimate() because it doesn't
 * use any PGrnScanOpaque. And pgroonga_costestimate() is always
 * called before them. So we'll be able to close opened grn_objs after
 * VACUUM in a timely manner. */
static bool
PGrnEnsureLatestDB(void)
{
	PGRN_TRACE_LOG_ENTER();

	if (!processSharedData)
	{
		PGRN_TRACE_LOG_EXIT();
		return false;
	}

	if (processLocalData.lastDBUnmapTimestamp >
		processSharedData->lastVacuumTimestamp)
	{
		PGRN_TRACE_LOG_EXIT();
		return false;
	}

	GRN_LOG(
		ctx, GRN_LOG_DEBUG, "pgroonga: unmap DB because VACUUM was executed");
	PGrnUnmapDB();
	processLocalData.lastDBUnmapTimestamp = GetCurrentTimestamp();

	PGRN_TRACE_LOG_EXIT();
	return true;
}

static grn_id
PGrnGetType(Relation index, AttrNumber n, unsigned char *flags)
{
	TupleDesc desc = RelationGetDescr(index);
	Form_pg_attribute attr;

	attr = TupleDescAttr(desc, n);
	return PGrnPGTypeToGrnType(attr->atttypid, flags);
}

static Datum
PGrnConvertToDatumArrayType(grn_obj *vector, Oid typeID)
{
	const char *tag = "[vector][groonga->postgresql-type]";
	Oid elementTypeID = InvalidOid;
	int elementLength = 0;
	bool elementByValue = false;
	char elementAlign = '\0';
	int i, n;
	Datum *values;

	switch (typeID)
	{
	case INT4ARRAYOID:
		elementTypeID = INT4OID;
		elementLength = 4;
		elementByValue = true;
		elementAlign = 'i';
		break;
	case FLOAT4ARRAYOID:
		elementTypeID = FLOAT4OID;
		elementLength = 4;
		elementByValue = true;
		elementAlign = 'i';
		break;
	case VARCHARARRAYOID:
		elementTypeID = VARCHAROID;
		elementLength = -1;
		elementByValue = false;
		elementAlign = 'i';
		break;
	case TEXTARRAYOID:
		elementTypeID = TEXTOID;
		elementLength = -1;
		elementByValue = false;
		elementAlign = 'i';
		break;
	default:
		PGrnCheckRC(GRN_FUNCTION_NOT_IMPLEMENTED,
					"%s unsupported datum array type: %u",
					tag,
					typeID);
		break;
	}

	n = grn_vector_size(ctx, vector);
	if (n == 0)
		PG_RETURN_POINTER(construct_empty_array(elementTypeID));

	values = palloc(sizeof(Datum) * n);
	if (vector->header.domain == GRN_VECTOR)
	{
		for (i = 0; i < n; i++)
		{
			const char *element;
			unsigned int elementSize;
			text *value;

			elementSize =
				grn_vector_get_element(ctx, vector, i, &element, NULL, NULL);
			value = cstring_to_text_with_len(element, elementSize);
			values[i] = PointerGetDatum(value);
		}
	}
	else
	{
		unsigned int elementSize = grn_uvector_element_size(ctx, vector);
		grn_obj element;
		GRN_VALUE_FIX_SIZE_INIT(
			&element, GRN_OBJ_DO_SHALLOW_COPY, vector->header.domain);
		for (i = 0; i < n; i++)
		{
			const char *rawElement = GRN_BULK_HEAD(vector) + (elementSize * i);
			GRN_TEXT_SET(ctx, &element, rawElement, elementSize);
			values[i] = PGrnConvertToDatum(&element, elementTypeID);
		}
		GRN_OBJ_FIN(ctx, &element);
	}

	{
		int dims[1];
		int lbs[1];

		dims[0] = n;
		lbs[0] = 1;
		PG_RETURN_POINTER(construct_md_array(values,
											 NULL,
											 1,
											 dims,
											 lbs,
											 elementTypeID,
											 elementLength,
											 elementByValue,
											 elementAlign));
	}
}

Datum
PGrnConvertToDatum(grn_obj *value, Oid typeID)
{
	const char *tag = "[data][groonga->postgresql]";

	switch (typeID)
	{
	case BOOLOID:
		PG_RETURN_BOOL(GRN_BOOL_VALUE(value));
		break;
	case INT2OID:
		PG_RETURN_INT16(GRN_INT16_VALUE(value));
		break;
	case INT4OID:
		PG_RETURN_INT32(GRN_INT32_VALUE(value));
		break;
	case INT8OID:
		PG_RETURN_INT64(GRN_INT64_VALUE(value));
		break;
	case FLOAT4OID:
		// For backward compatibility.
		// `FLOAT4OID` was also `GRN_DB_FLOAT` before.
		// Changed from this commit: 441411db727fa60186e01e3a564eccb6e192bb1a
		if (value->header.domain == GRN_DB_FLOAT)
			PG_RETURN_FLOAT4(GRN_FLOAT_VALUE(value));
		else
			PG_RETURN_FLOAT4(GRN_FLOAT32_VALUE(value));
		break;
	case FLOAT8OID:
		PG_RETURN_FLOAT8(GRN_FLOAT_VALUE(value));
		break;
	case TIMESTAMPOID:
	case TIMESTAMPTZOID:
	{
		int64 grnTime;
		int64 sec;
		int64 usec;
		TimestampTz timestamp;

		grnTime = GRN_TIME_VALUE(value);
		GRN_TIME_UNPACK(grnTime, sec, usec);
		if (typeID == TIMESTAMPOID)
		{
			timestamp = PGrnPGLocalTimeToTimestamp(sec);
		}
		else
		{
			/* TODO: Support not localtime time zone. */
			pg_time_t unixTimeUTC = sec;
			timestamp = time_t_to_timestamptz(unixTimeUTC);
		}
#ifdef HAVE_INT64_TIMESTAMP
		timestamp += usec;
#else
		timestamp += ((double) usec) / USECS_PER_SEC;
#endif
		if (typeID == TIMESTAMPOID)
			PG_RETURN_TIMESTAMP(timestamp);
		else
			PG_RETURN_TIMESTAMPTZ(timestamp);
		break;
	}
	case TEXTOID:
	case XMLOID:
	{
		text *text = cstring_to_text_with_len(GRN_TEXT_VALUE(value),
											  GRN_TEXT_LEN(value));
		PG_RETURN_TEXT_P(text);
		break;
	}
	case VARCHAROID:
	{
		text *text = cstring_to_text_with_len(GRN_TEXT_VALUE(value),
											  GRN_TEXT_LEN(value));
		PG_RETURN_VARCHAR_P((VarChar *) text);
		break;
	}
#ifdef NOT_USED
	case POINTOID:
		/* GRN_DB_TOKYO_GEO_POINT or GRN_DB_WGS84_GEO_POINT; */
		break;
#endif
	case INT4ARRAYOID:
	case FLOAT4ARRAYOID:
	case VARCHARARRAYOID:
	case TEXTARRAYOID:
		return PGrnConvertToDatumArrayType(value, typeID);
		break;
	case UUIDOID:
	{
#define UUID_TEXT_SIZE 37 /* "12345678-abcd-bcde-cdef-123456789012" + '\0' */
		char uuid[UUID_TEXT_SIZE];
		memcpy(uuid,
			   GRN_TEXT_VALUE(value),
			   GRN_TEXT_LEN(value) > UUID_TEXT_SIZE - 1 ? UUID_TEXT_SIZE - 1
														: GRN_TEXT_LEN(value));
		uuid[UUID_TEXT_SIZE - 1] = '\0';
#undef UUID_TEXT_SIZE
		return DirectFunctionCall1(uuid_in, CStringGetDatum(uuid));
		break;
	}
	default:
		PGrnCheckRC(GRN_FUNCTION_NOT_IMPLEMENTED,
					"%s unsupported datum type: %u",
					tag,
					typeID);
		break;
	}

	return 0;
}

static bool
PGrnIsQueryStrategyIndex(Relation index, int nthAttribute)
{
	Oid strategyOID;
	Oid leftType;
	Oid rightType;

	leftType = index->rd_opcintype[nthAttribute];

	switch (leftType)
	{
	case VARCHARARRAYOID:
		rightType = VARCHAROID;
		break;
	case TEXTARRAYOID:
		rightType = TEXTOID;
		break;
	default:
		rightType = leftType;
		break;
	}

	strategyOID = get_opfamily_member(index->rd_opfamily[nthAttribute],
									  leftType,
									  rightType,
									  PGrnQueryStrategyNumber);
	if (OidIsValid(strategyOID))
		return true;

	strategyOID = get_opfamily_member(index->rd_opfamily[nthAttribute],
									  leftType,
									  rightType,
									  PGrnQueryStrategyV2Number);
	if (OidIsValid(strategyOID))
		return true;

	strategyOID = get_opfamily_member(index->rd_opfamily[nthAttribute],
									  leftType,
									  rightType,
									  PGrnQueryStrategyV2DeprecatedNumber);
	if (OidIsValid(strategyOID))
		return true;

	return false;
}

static bool
PGrnIsQueryInStrategyIndex(Relation index, int nthAttribute)
{
	Oid strategyOID;
	Oid leftType;
	Oid rightType;

	leftType = index->rd_opcintype[nthAttribute];

	switch (leftType)
	{
	case VARCHAROID:
		rightType = VARCHARARRAYOID;
		break;
	case TEXTOID:
		rightType = TEXTARRAYOID;
		break;
	default:
		rightType = leftType;
		break;
	}

	strategyOID = get_opfamily_member(index->rd_opfamily[nthAttribute],
									  leftType,
									  rightType,
									  PGrnQueryInStrategyV2Number);
	if (OidIsValid(strategyOID))
		return true;

	strategyOID = get_opfamily_member(index->rd_opfamily[nthAttribute],
									  leftType,
									  rightType,
									  PGrnQueryInStrategyV2DeprecatedNumber);
	if (OidIsValid(strategyOID))
		return true;

	strategyOID = get_opfamily_member(index->rd_opfamily[nthAttribute],
									  leftType,
									  rightType,
									  PGrnQueryInStrategyV2Deprecated2Number);
	if (OidIsValid(strategyOID))
		return true;

	return false;
}

static bool
PGrnIsScriptStrategyIndex(Relation index, int nthAttribute)
{
	Oid strategyOID;
	Oid leftType;
	Oid rightType;

	leftType = index->rd_opcintype[nthAttribute];

	switch (leftType)
	{
	case VARCHARARRAYOID:
		rightType = VARCHAROID;
		break;
	case TEXTARRAYOID:
		rightType = TEXTOID;
		break;
	default:
		rightType = leftType;
		break;
	}

	strategyOID = get_opfamily_member(index->rd_opfamily[nthAttribute],
									  leftType,
									  rightType,
									  PGrnScriptStrategyV2Number);
	if (OidIsValid(strategyOID))
		return true;

	return false;
}

static bool
PGrnIsForFullTextSearchIndex(Relation index, int nthAttribute)
{
	if (PGrnIsQueryStrategyIndex(index, nthAttribute))
		return true;

	if (PGrnIsQueryInStrategyIndex(index, nthAttribute))
		return true;

	if (PGrnIsScriptStrategyIndex(index, nthAttribute))
		return true;

	return false;
}

static bool
PGrnIsRegexpStrategyIndex(Relation index, int nthAttribute)
{
	Oid regexpStrategyOID;
	Oid leftType;
	Oid rightType;

	leftType = index->rd_opcintype[nthAttribute];
	rightType = leftType;
	regexpStrategyOID = get_opfamily_member(index->rd_opfamily[nthAttribute],
											leftType,
											rightType,
											PGrnRegexpStrategyNumber);
	return OidIsValid(regexpStrategyOID);
}

static bool
PGrnIsRegexpStrategyV2Index(Relation index, int nthAttribute)
{
	Oid regexpStrategyOID;
	Oid leftType;
	Oid rightType;

	leftType = index->rd_opcintype[nthAttribute];

	switch (leftType)
	{
	case TEXTARRAYOID:
		rightType = TEXTOID;
		break;
	default:
		rightType = leftType;
		break;
	}

	regexpStrategyOID = get_opfamily_member(index->rd_opfamily[nthAttribute],
											leftType,
											rightType,
											PGrnRegexpStrategyV2Number);
	return OidIsValid(regexpStrategyOID);
}

static bool
PGrnIsForRegexpSearchIndex(Relation index, int nthAttribute)
{
	if (PGrnIsRegexpStrategyIndex(index, nthAttribute))
		return true;

	if (PGrnIsRegexpStrategyV2Index(index, nthAttribute))
		return true;

	return false;
}

static bool
PGrnIsForPrefixSearchIndex(Relation index, int nthAttribute)
{
	Oid prefixStrategyOID;
	Oid prefixInStrategyOID;
	Oid leftType;
	Oid rightType;

	leftType = index->rd_opcintype[nthAttribute];

	switch (leftType)
	{
	case VARCHARARRAYOID:
		rightType = VARCHAROID;
		break;
	case TEXTARRAYOID:
		rightType = TEXTOID;
		break;
	default:
		rightType = leftType;
		break;
	}

	prefixStrategyOID = get_opfamily_member(index->rd_opfamily[nthAttribute],
											leftType,
											rightType,
											PGrnPrefixStrategyV2Number);
	if (OidIsValid(prefixStrategyOID))
		return true;

	prefixStrategyOID =
		get_opfamily_member(index->rd_opfamily[nthAttribute],
							leftType,
							rightType,
							PGrnPrefixConditionStrategyV2Number);
	if (OidIsValid(prefixStrategyOID))
		return true;

	prefixStrategyOID =
		get_opfamily_member(index->rd_opfamily[nthAttribute],
							leftType,
							rightType,
							PGrnPrefixFTSConditionStrategyV2Number);
	if (OidIsValid(prefixStrategyOID))
		return true;

	prefixStrategyOID =
		get_opfamily_member(index->rd_opfamily[nthAttribute],
							leftType,
							rightType,
							PGrnPrefixStrategyV2DeprecatedNumber);
	if (OidIsValid(prefixStrategyOID))
		return true;

	prefixInStrategyOID = get_opfamily_member(index->rd_opfamily[nthAttribute],
											  leftType,
											  rightType,
											  PGrnPrefixInStrategyV2Number);
	if (OidIsValid(prefixInStrategyOID))
		return true;

	return false;
}

static bool
PGrnIsForInclude(Relation index, int nthAttribute)
{
	return nthAttribute >= IndexRelationGetNumberOfKeyAttributes(index);
}

static bool
PGrnIsForSemanticSearchIndex(Relation index, int nthAttribute)
{
	Oid opFamilyOID;
	char *name;
	bool forSemanticSearch;

	if (PGrnIsForInclude(index, nthAttribute))
		return false;

	opFamilyOID = index->rd_opfamily[nthAttribute];
	if (!OidIsValid(opFamilyOID))
		return false;

	name = pgrn_get_opfamily_name(opFamilyOID, false);
	forSemanticSearch =
		(strcmp(name, "pgroonga_text_semantic_search_ops_v2") == 0);
	pfree(name);
	return forSemanticSearch;
}

static void
PGrnCreateCheckType(PGrnCreateData *data)
{
	const char *tag = "[create][type][check]";
	TupleDesc desc = RelationGetDescr(data->index);
	Form_pg_attribute attr;
	int32 maxLength;

	attr = TupleDescAttr(desc, data->i);
	if (data->forFullTextSearch)
		return;
	if (data->forRegexpSearch)
		return;

	switch (attr->atttypid)
	{
	case VARCHAROID:
	case VARCHARARRAYOID:
		maxLength = type_maximum_size(VARCHAROID, attr->atttypmod);
		if (maxLength > 4096)
		{
			PGrnCheckRC(GRN_FUNCTION_NOT_IMPLEMENTED,
						"%s 4097bytes over size varchar isn't supported: %d",
						tag,
						maxLength);
		}
		break;
	default:
		break;
	}
}

static void PGrnRemoveUnusedTable(Relation index, Oid relationFileNodeID);

static void
PGrnCreate(PGrnCreateData *data)
{
	/*
	 * If CREATE TABLE and TRUNCATE TABLE exist in the same
	 * transaction, PostgreSQL reuses the created table instead of
	 * creating a new table. We need to remove existing Groonga tables
	 * and columns in the case.
	 */
	{
		char sourcesTableName[GRN_TABLE_MAX_KEY_SIZE];
		grn_obj *sourcesTable;

		snprintf(sourcesTableName,
				 sizeof(sourcesTableName),
				 PGrnSourcesTableNameFormat,
				 data->relNumber);
		sourcesTable = grn_ctx_get(ctx, sourcesTableName, -1);
		if (sourcesTable)
		{
			grn_obj_unlink(ctx, sourcesTable);
			PGrnRemoveUnusedTable(data->index, data->relNumber);
		}
	}

	PGrnCreateSourcesTable(data);

	for (data->i = 0; data->i < data->desc->natts; data->i++)
	{
		bool forInclude = PGrnIsForInclude(data->index, data->i);
		Form_pg_attribute attribute = TupleDescAttr(data->desc, data->i);
		if (PGrnAttributeIsJSONB(attribute->atttypid))
		{
			if (forInclude)
				continue;
			data->forFullTextSearch = false;
			data->forRegexpSearch = false;
			data->forPrefixSearch = false;
			data->forSemanticSearch = false;
			PGrnJSONBCreate(data);
		}
		else
		{
			data->forFullTextSearch =
				PGrnIsForFullTextSearchIndex(data->index, data->i);
			data->forRegexpSearch =
				PGrnIsForRegexpSearchIndex(data->index, data->i);
			data->forPrefixSearch =
				PGrnIsForPrefixSearchIndex(data->index, data->i);
			data->forSemanticSearch =
				PGrnIsForSemanticSearchIndex(data->index, data->i);
			data->attributeTypeID =
				PGrnGetType(data->index, data->i, &(data->attributeFlags));
			PGrnCreateCheckType(data);
			if (!forInclude || data->forPrefixSearch)
				PGrnCreateLexicon(data);
			PGrnCreateDataColumn(data);
			if (forInclude)
				continue;
			PGrnCreateIndexColumn(data);
		}
	}
}

static void
PGrnSetSources(Relation index, grn_obj *sourcesTable)
{
	TupleDesc desc;
	unsigned int i;

	desc = RelationGetDescr(index);
	for (i = 0; i < desc->natts; i++)
	{
		bool forInclude = PGrnIsForInclude(index, i);
		Form_pg_attribute attribute = TupleDescAttr(desc, i);
		NameData *name = &(attribute->attname);
		grn_obj *source;
		grn_obj *indexColumn;

		if (forInclude)
			continue;

		if (PGrnAttributeIsJSONB(attribute->atttypid))
		{
			indexColumn = PGrnJSONBSetSource(index, i);
		}
		else
		{
			indexColumn = PGrnLookupIndexColumn(index, i, ERROR);
		}

		source = PGrnLookupColumn(sourcesTable, name->data, ERROR);
		PGrnIndexColumnSetSource(index, indexColumn, source);
		grn_obj_unlink(ctx, source);
		grn_obj_unlink(ctx, indexColumn);
	}
}

static double
PGrnCollectScoreGetScore(Relation table, PGrnScanOpaque so, grn_id recordID)
{
	double score = 0.0;
	grn_id id;

	id = grn_table_get(ctx, so->searched, &recordID, sizeof(grn_id));
	if (id == GRN_ID_NIL)
		return 0.0;

	GRN_BULK_REWIND(&(buffers->ctid));
	grn_obj_get_value(ctx, so->ctidAccessor, id, &(buffers->ctid));
	if (GRN_BULK_VSIZE(&(buffers->ctid)) == 0)
		return 0.0;

	{
		ItemPointerData ctid;
		ctid = PGrnCtidUnpack(GRN_UINT64_VALUE(&(buffers->ctid)));
		if (!PGrnCtidIsAlive(table, &ctid))
			return 0.0;
	}

	GRN_BULK_REWIND(&(buffers->score));
	grn_obj_get_value(ctx, so->scoreAccessor, id, &(buffers->score));
	if (buffers->score.header.domain == GRN_DB_FLOAT)
	{
		score = GRN_FLOAT_VALUE(&(buffers->score));
	}
	else
	{
		score = GRN_INT32_VALUE(&(buffers->score));
	}

	return score;
}

static double
PGrnCollectScoreOneColumnPrimaryKey(Relation table,
									HeapTuple tuple,
									PGrnScanOpaque so)
{
	double score = 0.0;
	TupleDesc desc;
	PGrnPrimaryKeyColumn *primaryKeyColumn;
	grn_index_datum indexDatum;
	grn_obj *lexicon;
	grn_id termID;
	grn_ii_cursor *iiCursor;
	int iiNElements = 2;
	grn_posting *posting;

	desc = RelationGetDescr(table);
	primaryKeyColumn = slist_container(
		PGrnPrimaryKeyColumn, node, so->primaryKeyColumns.head.next);

	{
		unsigned int nIndexData;

		nIndexData = grn_column_find_index_data(
			ctx, primaryKeyColumn->column, GRN_OP_EQUAL, &indexDatum, 1);
		if (nIndexData == 0)
			return 0.0;
	}

	lexicon = grn_ctx_at(ctx, indexDatum.index->header.domain);
	if (!lexicon)
		return 0.0;

	{
		bool isNULL;
		Datum primaryKeyValue;

		grn_obj_reinit(ctx,
					   &(buffers->general),
					   primaryKeyColumn->domain,
					   primaryKeyColumn->flags);
		primaryKeyValue =
			heap_getattr(tuple, primaryKeyColumn->number, desc, &isNULL);
		PGrnConvertFromData(
			primaryKeyValue, primaryKeyColumn->type, &(buffers->general));
	}
	termID = grn_table_get(ctx,
						   lexicon,
						   GRN_BULK_HEAD(&(buffers->general)),
						   GRN_BULK_VSIZE(&(buffers->general)));
	if (termID == GRN_ID_NIL)
		return 0.0;

	iiCursor = grn_ii_cursor_open(ctx,
								  (grn_ii *) (indexDatum.index),
								  termID,
								  GRN_ID_NIL,
								  GRN_ID_NIL,
								  iiNElements,
								  0);
	if (!iiCursor)
		return 0.0;

	while ((posting = grn_ii_cursor_next(ctx, iiCursor)))
	{
		score += PGrnCollectScoreGetScore(table, so, posting->rid);
	}
	grn_ii_cursor_close(ctx, iiCursor);

	return score;
}

static double
PGrnCollectScoreMultiColumnPrimaryKey(Relation table,
									  HeapTuple tuple,
									  PGrnScanOpaque so)
{
	const char *tag = "[score][multi-column-primary-key][collect]";
	double score = 0.0;
	TupleDesc desc;
	grn_obj *expression;
	grn_obj *variable;
	slist_iter iter;
	unsigned int nPrimaryKeyColumns = 0;

	desc = RelationGetDescr(table);

	if (!so->scoreTargetRecords)
	{
		so->scoreTargetRecords =
			grn_table_create(ctx,
							 NULL,
							 0,
							 NULL,
							 GRN_OBJ_TABLE_HASH_KEY | GRN_OBJ_WITH_SUBREC,
							 so->sourcesTable,
							 NULL);
	}

	GRN_EXPR_CREATE_FOR_QUERY(ctx, so->sourcesTable, expression, variable);

	slist_foreach(iter, &(so->primaryKeyColumns))
	{
		PGrnPrimaryKeyColumn *primaryKeyColumn;
		bool isNULL;
		Datum primaryKeyValue;

		primaryKeyColumn =
			slist_container(PGrnPrimaryKeyColumn, node, iter.cur);

		grn_obj_reinit(ctx,
					   &(buffers->general),
					   primaryKeyColumn->domain,
					   primaryKeyColumn->flags);

		primaryKeyValue =
			heap_getattr(tuple, primaryKeyColumn->number, desc, &isNULL);
		PGrnConvertFromData(
			primaryKeyValue, primaryKeyColumn->type, &(buffers->general));

		PGrnExprAppendObject(expression,
							 primaryKeyColumn->column,
							 GRN_OP_GET_VALUE,
							 1,
							 tag,
							 NULL);
		PGrnExprAppendConst(
			expression, &(buffers->general), GRN_OP_PUSH, 1, tag);
		PGrnExprAppendOp(expression, GRN_OP_EQUAL, 2, tag, NULL);

		if (nPrimaryKeyColumns > 0)
			PGrnExprAppendOp(expression, GRN_OP_AND, 2, tag, NULL);
		nPrimaryKeyColumns++;
	}
	grn_table_select(
		ctx, so->sourcesTable, expression, so->scoreTargetRecords, GRN_OP_OR);
	grn_obj_close(ctx, expression);

	{
		grn_table_cursor *tableCursor;

		tableCursor = grn_table_cursor_open(ctx,
											so->scoreTargetRecords,
											NULL,
											0,
											NULL,
											0,
											0,
											-1,
											GRN_CURSOR_ASCENDING);
		while (grn_table_cursor_next(ctx, tableCursor) != GRN_ID_NIL)
		{
			void *key;
			grn_id recordID;

			grn_table_cursor_get_key(ctx, tableCursor, &key);
			recordID = *((grn_id *) key);
			grn_table_cursor_delete(ctx, tableCursor);

			score += PGrnCollectScoreGetScore(table, so, recordID);
		}
		grn_obj_unlink(ctx, tableCursor);
	}

	return score;
}

static bool
PGrnCollectScoreIsTarget(PGrnScanOpaque so, Oid tableOid)
{
	NameData soTableName;

	if (so->dataTableID != tableOid)
	{
		NameData tableName;
		GRN_LOG(ctx,
				GRN_LOG_DEBUG,
				"pgroonga: [score][target][no] different table: "
				"<%s>(%u) != <%s>(%u)",
				PGrnPGGetRelationNameByID(so->dataTableID, soTableName.data),
				so->dataTableID,
				PGrnPGGetRelationNameByID(tableOid, tableName.data),
				tableOid);
		return false;
	}

	if (!so->scoreAccessor)
	{
		GRN_LOG(ctx,
				GRN_LOG_DEBUG,
				"pgroonga: [score][target][no] no score accessor: <%s>(%u)",
				PGrnPGGetRelationNameByID(so->dataTableID, soTableName.data),
				so->dataTableID);
		return false;
	}

	GRN_LOG(ctx,
			GRN_LOG_DEBUG,
			"pgroonga: [score][target][yes] <%s>(%u)",
			PGrnPGGetRelationNameByID(so->dataTableID, soTableName.data),
			so->dataTableID);

	return true;
}

static double
PGrnCollectScore(Relation table, HeapTuple tuple)
{
	double score = 0.0;
	dlist_iter iter;

	dlist_foreach(iter, &PGrnScanOpaques)
	{
		PGrnScanOpaque so = dlist_container(PGrnScanOpaqueData, node, iter.cur);

		if (!PGrnCollectScoreIsTarget(so, tuple->t_tableOid))
			continue;

		if (slist_is_empty(&(so->primaryKeyColumns)))
			continue;

		if (so->primaryKeyColumns.head.next->next)
		{
			score += PGrnCollectScoreMultiColumnPrimaryKey(table, tuple, so);
		}
		else
		{
			score += PGrnCollectScoreOneColumnPrimaryKey(table, tuple, so);
		}
	}

	return score;
}

/**
 * pgroonga_score(row record) : float8
 *
 * It's deprecated since 2.0.4. Just for backward compatibility.
 */
Datum
pgroonga_score(PG_FUNCTION_ARGS)
{
	return pgroonga_score_row(fcinfo);
}

/**
 * pgroonga_score(row record) : float8
 */
Datum
pgroonga_score_row(PG_FUNCTION_ARGS)
{
	HeapTupleHeader header = PG_GETARG_HEAPTUPLEHEADER(0);
	Oid type;
	int32 recordType;
	TupleDesc desc;
	double score = 0.0;

	type = HeapTupleHeaderGetTypeId(header);
	recordType = HeapTupleHeaderGetTypMod(header);
	desc = lookup_rowtype_tupdesc(type, recordType);

	if (desc->natts > 0 && !dlist_is_empty(&PGrnScanOpaques))
	{
		HeapTupleData tupleData;
		HeapTuple tuple;
		Relation table;

		tupleData.t_len = HeapTupleHeaderGetDatumLength(header);
		tupleData.t_tableOid = TupleDescAttr(desc, 0)->attrelid;
		tupleData.t_data = header;
		ItemPointerSetInvalid(&(tupleData.t_self));
		tuple = &tupleData;

		table = RelationIdGetRelation(tuple->t_tableOid);

		score = PGrnCollectScore(table, tuple);

		RelationClose(table);
	}

	ReleaseTupleDesc(desc);

	PG_RETURN_FLOAT8(score);
}

static void
PGrnScanOpaqueCreateCtidResolveTable(PGrnScanOpaque so)
{
	const char *tag = "pgroonga: [ctid-resolve-table][create]";
	Relation table;
	grn_obj *sourceRecord;
	grn_column_cache *sourcesCtidColumnCache = NULL;

	table = RelationIdGetRelation(so->dataTableID);

	GRN_LOG(ctx,
			GRN_LOG_DEBUG,
			"%s[start] <%s>(%u)",
			tag,
			table->rd_rel->relname.data,
			so->dataTableID);

	sourceRecord = &(buffers->general);
	grn_obj_reinit(ctx, sourceRecord, grn_obj_id(ctx, so->sourcesTable), 0);

	if (so->sourcesCtidColumn)
		sourcesCtidColumnCache =
			grn_column_cache_open(ctx, so->sourcesCtidColumn);

	so->ctidResolveTable = grn_table_create(ctx,
											NULL,
											0,
											NULL,
											GRN_OBJ_TABLE_HASH_KEY,
											grn_ctx_at(ctx, GRN_DB_UINT64),
											so->sourcesTable);
	GRN_TABLE_EACH_BEGIN(ctx, so->searched, cursor, id)
	{
		void *key;
		grn_id sourceID;
		uint64_t packedCtid = 0;
		ItemPointerData ctid;
		ItemPointerData resolvedCtid;
		uint64_t resolvedPackedCtid;
		grn_id resolvedID;

		grn_table_cursor_get_key(ctx, cursor, &key);
		sourceID = *((grn_id *) key);

		if (sourcesCtidColumnCache)
		{
			void *ctidColumnValue;
			size_t ctidColumnValueSize;
			ctidColumnValue = grn_column_cache_ref(
				ctx, sourcesCtidColumnCache, sourceID, &ctidColumnValueSize);
			if (ctidColumnValueSize != sizeof(uint64_t))
			{
				GRN_LOG(ctx,
						GRN_LOG_DEBUG,
						"%s[ignore] <%s>(%u): <%u>: "
						"<%" PGRN_PRIuSIZE "> != <%" PGRN_PRIuSIZE ">",
						tag,
						table->rd_rel->relname.data,
						so->dataTableID,
						sourceID,
						ctidColumnValueSize,
						sizeof(uint64_t));
				continue;
			}
			packedCtid = *((uint64_t *) ctidColumnValue);
		}
		else
		{
			int keySize;

			keySize = grn_table_get_key(
				ctx, so->sourcesTable, sourceID, &packedCtid, sizeof(uint64_t));
			if (keySize != sizeof(uint64_t))
			{
				GRN_LOG(ctx,
						GRN_LOG_DEBUG,
						"%s[ignore] <%s>(%u): <%u>: "
						"<%d> != <%" PGRN_PRIuSIZE ">",
						tag,
						table->rd_rel->relname.data,
						so->dataTableID,
						sourceID,
						keySize,
						sizeof(uint64_t));
				continue;
			}
		}
		ctid = PGrnCtidUnpack(packedCtid);
		resolvedCtid = ctid;
		if (!PGrnCtidIsAlive(table, &resolvedCtid))
		{
			GRN_LOG(ctx,
					GRN_LOG_DEBUG,
					"%s[ignore][dead] <%s>(%u): <%u>",
					tag,
					table->rd_rel->relname.data,
					so->dataTableID,
					sourceID);
			continue;
		}

		if (!sourcesCtidColumnCache && ItemPointerEquals(&ctid, &resolvedCtid))
		{
			GRN_LOG(ctx,
					GRN_LOG_DEBUG,
					"%s[ignore][not-hot] <%s>(%u): <%u>: <(%u,%u),%u>",
					tag,
					table->rd_rel->relname.data,
					so->dataTableID,
					sourceID,
					ctid.ip_blkid.bi_hi,
					ctid.ip_blkid.bi_lo,
					ctid.ip_posid);
			continue;
		}

		resolvedPackedCtid = PGrnCtidPack(&resolvedCtid);
		resolvedID = grn_table_add(ctx,
								   so->ctidResolveTable,
								   &resolvedPackedCtid,
								   sizeof(uint64_t),
								   NULL);
		GRN_RECORD_SET(ctx, sourceRecord, sourceID);
		grn_obj_set_value(
			ctx, so->ctidResolveTable, resolvedID, sourceRecord, GRN_OBJ_SET);
		GRN_LOG(ctx,
				GRN_LOG_DEBUG,
				"%s[add] <%s>(%u): <%u>: <(%u,%u),%u> -> <(%u,%u),%u>",
				tag,
				table->rd_rel->relname.data,
				so->dataTableID,
				sourceID,
				ctid.ip_blkid.bi_hi,
				ctid.ip_blkid.bi_lo,
				ctid.ip_posid,
				resolvedCtid.ip_blkid.bi_hi,
				resolvedCtid.ip_blkid.bi_lo,
				resolvedCtid.ip_posid);
	}
	GRN_TABLE_EACH_END(ctx, cursor);

	if (sourcesCtidColumnCache)
		grn_column_cache_close(ctx, sourcesCtidColumnCache);

	GRN_LOG(ctx,
			GRN_LOG_DEBUG,
			"%s[end] <%s>(%u)",
			tag,
			table->rd_rel->relname.data,
			so->dataTableID);

	RelationClose(table);
}

static double
PGrnCollectScoreCtid(PGrnScanOpaque so, ItemPointer ctid)
{
	const char *tag = "pgroonga: [score][ctid][collect]";
	const uint64_t packedCtid = PGrnCtidPack(ctid);
	double score = 0.0;
	grn_id resolveID;
	grn_id sourceID = GRN_ID_NIL;
	grn_id searchedID;

	if (so->sourcesTable->header.type != GRN_TABLE_NO_KEY)
	{
		sourceID =
			grn_table_get(ctx, so->sourcesTable, &packedCtid, sizeof(uint64_t));
	}

	if (sourceID == GRN_ID_NIL)
	{
		if (!so->ctidResolveTable)
			PGrnScanOpaqueCreateCtidResolveTable(so);

		resolveID = grn_table_get(
			ctx, so->ctidResolveTable, &packedCtid, sizeof(uint64_t));
		if (resolveID != GRN_ID_NIL)
		{
			{
				NameData soTableName;
				GRN_LOG(ctx,
						GRN_LOG_DEBUG,
						"%s[hot-resolved] <%s>(%u):<(%u,%u),%u>:<%u>",
						tag,
						PGrnPGGetRelationNameByID(so->dataTableID,
												  soTableName.data),
						so->dataTableID,
						ctid->ip_blkid.bi_hi,
						ctid->ip_blkid.bi_lo,
						ctid->ip_posid,
						resolveID);
			}
			GRN_BULK_REWIND(&(buffers->general));
			grn_obj_get_value(
				ctx, so->ctidResolveTable, resolveID, &(buffers->general));
			sourceID = GRN_RECORD_VALUE(&(buffers->general));
		}
	}

	if (sourceID == GRN_ID_NIL)
	{
		NameData soTableName;
		GRN_LOG(ctx,
				GRN_LOG_DEBUG,
				"%s[no-record] <%s>(%u):<(%u,%u),%u>",
				tag,
				PGrnPGGetRelationNameByID(so->dataTableID, soTableName.data),
				so->dataTableID,
				ctid->ip_blkid.bi_hi,
				ctid->ip_blkid.bi_lo,
				ctid->ip_posid);
		return 0.0;
	}

	searchedID = grn_table_get(ctx, so->searched, &sourceID, sizeof(grn_id));
	if (searchedID == GRN_ID_NIL)
	{
		NameData soTableName;
		GRN_LOG(ctx,
				GRN_LOG_DEBUG,
				"%s[not-match] <%s>(%u):<(%u,%u),%u>:<%u>",
				tag,
				PGrnPGGetRelationNameByID(so->dataTableID, soTableName.data),
				so->dataTableID,
				ctid->ip_blkid.bi_hi,
				ctid->ip_blkid.bi_lo,
				ctid->ip_posid,
				sourceID);
		return 0.0;
	}

	GRN_BULK_REWIND(&(buffers->score));
	grn_obj_get_value(ctx, so->scoreAccessor, searchedID, &(buffers->score));
	if (buffers->score.header.domain == GRN_DB_FLOAT)
	{
		score = GRN_FLOAT_VALUE(&(buffers->score));
	}
	else
	{
		score = GRN_INT32_VALUE(&(buffers->score));
	}

	{
		NameData soTableName;
		GRN_LOG(ctx,
				GRN_LOG_DEBUG,
				"%s[found] <%s>(%u):<(%u,%u),%u>: <%u> -> <%u>: <%f>",
				tag,
				PGrnPGGetRelationNameByID(so->dataTableID, soTableName.data),
				so->dataTableID,
				ctid->ip_blkid.bi_hi,
				ctid->ip_blkid.bi_lo,
				ctid->ip_posid,
				sourceID,
				searchedID,
				score);
	}

	return score;
}

/**
 * pgroonga_score_ctid(tableoid oid, ctid tid) : float8
 */
Datum
pgroonga_score_ctid(PG_FUNCTION_ARGS)
{
	Oid tableOid = PG_GETARG_OID(0);
	ItemPointer ctid = (ItemPointer) PG_GETARG_POINTER(1);
	double score = 0.0;
	dlist_iter iter;

	dlist_foreach(iter, &PGrnScanOpaques)
	{
		PGrnScanOpaque so;

		so = dlist_container(PGrnScanOpaqueData, node, iter.cur);
		if (!PGrnCollectScoreIsTarget(so, tableOid))
			continue;

		score += PGrnCollectScoreCtid(so, ctid);
	}

	{
		NameData tableName;
		GRN_LOG(ctx,
				GRN_LOG_DEBUG,
				"pgroonga: [score][ctid] <%s>(%u):<(%u,%u),%u>: <%f>",
				PGrnPGGetRelationNameByID(tableOid, tableName.data),
				tableOid,
				ctid->ip_blkid.bi_hi,
				ctid->ip_blkid.bi_lo,
				ctid->ip_posid,
				score);
	}

	PG_RETURN_FLOAT8(score);
}

/**
 * pgroonga_table_name(indexName cstring) : text
 */
Datum
pgroonga_table_name(PG_FUNCTION_ARGS)
{
	const char *indexName = PG_GETARG_CSTRING(0);
	char tableNameBuffer[GRN_TABLE_MAX_KEY_SIZE];
	text *tableName;

	PGrnFormatSourcesTableName(indexName, tableNameBuffer);
	tableName = cstring_to_text(tableNameBuffer);
	PG_RETURN_TEXT_P(tableName);
}

static void
PGrnCommandReceive(grn_ctx *ctx, int flags, void *user_data)
{
	grn_rc rc = ctx->rc;
	char *chunk;
	unsigned int chunkSize;
	int recv_flags;
	grn_ctx_recv(ctx, &chunk, &chunkSize, &recv_flags);
	GRN_TEXT_PUT(ctx, &(buffers->body), chunk, chunkSize);

	if (!(flags & GRN_CTX_TAIL))
	{
		return;
	}

	grn_output_envelope(
		ctx, rc, &(buffers->head), &(buffers->body), &(buffers->foot), NULL, 0);
}

/**
 * pgroonga.command(groongaCommand text) : text
 * pgroonga.command(groongaCommandName text, arguments text[]) : text
 */
Datum
pgroonga_command(PG_FUNCTION_ARGS)
{
	text *groongaCommand = PG_GETARG_TEXT_PP(0);
	text *result;

	GRN_BULK_REWIND(&(buffers->head));
	GRN_BULK_REWIND(&(buffers->body));
	GRN_BULK_REWIND(&(buffers->foot));

	if (PG_NARGS() == 2)
	{
		grn_obj *command = &(buffers->general);
		Datum arguments = PG_GETARG_DATUM(1);
		AnyArrayType *argumentsArray = DatumGetAnyArrayP(arguments);
		int i, n;

		if (AARR_NDIM(argumentsArray) == 0)
			n = 0;
		else
			n = AARR_DIMS(argumentsArray)[0];

		grn_obj_reinit(ctx, command, GRN_DB_TEXT, 0);
		GRN_TEXT_PUT(ctx,
					 command,
					 VARDATA_ANY(groongaCommand),
					 VARSIZE_ANY_EXHDR(groongaCommand));
		for (i = 1; i <= n; i += 2)
		{
			int nameIndex = i;
			Datum nameDatum;
			text *name;
			int valueIndex = i + 1;
			Datum valueDatum;
			text *value;
			bool isNULL;

			nameDatum = array_get_element(
				arguments, 1, &nameIndex, -1, -1, false, 'i', &isNULL);
			if (isNULL)
				continue;
			valueDatum = array_get_element(
				arguments, 1, &valueIndex, -1, -1, false, 'i', &isNULL);
			if (isNULL)
				continue;

			name = DatumGetTextPP(nameDatum);
			value = DatumGetTextPP(valueDatum);

			GRN_TEXT_PUTS(ctx, command, " --");
			GRN_TEXT_PUT(
				ctx, command, VARDATA_ANY(name), VARSIZE_ANY_EXHDR(name));
			GRN_TEXT_PUTC(ctx, command, ' ');
			PGrnCommandEscapeValue(
				VARDATA_ANY(value), VARSIZE_ANY_EXHDR(value), command);
		}
		grn_ctx_recv_handler_set(ctx, PGrnCommandReceive, NULL);
		grn_ctx_send(ctx, GRN_TEXT_VALUE(command), GRN_TEXT_LEN(command), 0);
	}
	else
	{
		grn_ctx_recv_handler_set(ctx, PGrnCommandReceive, NULL);
		grn_ctx_send(ctx,
					 VARDATA_ANY(groongaCommand),
					 VARSIZE_ANY_EXHDR(groongaCommand),
					 0);
	}
	grn_ctx_recv_handler_set(ctx, NULL, NULL);

	grn_obj_reinit(ctx, &(buffers->general), GRN_DB_TEXT, 0);
	GRN_TEXT_PUT(ctx,
				 &(buffers->general),
				 GRN_TEXT_VALUE(&(buffers->head)),
				 GRN_TEXT_LEN(&(buffers->head)));
	GRN_TEXT_PUT(ctx,
				 &(buffers->general),
				 GRN_TEXT_VALUE(&(buffers->body)),
				 GRN_TEXT_LEN(&(buffers->body)));
	GRN_TEXT_PUT(ctx,
				 &(buffers->general),
				 GRN_TEXT_VALUE(&(buffers->foot)),
				 GRN_TEXT_LEN(&(buffers->foot)));
	result = cstring_to_text_with_len(GRN_TEXT_VALUE(&(buffers->general)),
									  GRN_TEXT_LEN(&(buffers->general)));
	PG_RETURN_TEXT_P(result);
}

typedef bool (*PGrnBinaryOperatorStringFunction)(const char *leftOperand,
												 unsigned int leftOperandSize,
												 PGrnCondition *condition);

static bool
pgroonga_execute_binary_operator_string_array(
	ArrayType *leftOperands,
	PGrnCondition *condition,
	PGrnBinaryOperatorStringFunction operator)
{
	bool matched = false;
	ArrayIterator iterator;
	int i;
	int nTargets = 0;
	Datum leftOperandDatum;
	bool isNULL;

	if (ARR_NDIM(leftOperands) == 0)
		return false;

	iterator = array_create_iterator(leftOperands, 0, NULL);
	if (condition->isTargets)
		nTargets = GRN_BULK_VSIZE(condition->isTargets) / sizeof(bool);
	for (i = 0; array_iterate(iterator, &leftOperandDatum, &isNULL); i++)
	{
		const char *leftOperand = NULL;
		unsigned int leftOperandSize = 0;

		if (nTargets > i && !GRN_BOOL_VALUE_AT(condition->isTargets, i))
			continue;

		if (isNULL)
			continue;

		PGrnPGDatumExtractString(leftOperandDatum,
								 ARR_ELEMTYPE(leftOperands),
								 &leftOperand,
								 &leftOperandSize);
		if (!leftOperand)
			continue;

		if (operator(leftOperand, leftOperandSize, condition))
		{
			matched = true;
			break;
		}
	}
	array_free_iterator(iterator);

	return matched;
}

static bool
pgroonga_execute_binary_operator_string_array_condition_raw(
	ArrayType *leftOperands,
	HeapTupleHeader header,
	PGrnBinaryOperatorStringFunction operator)
{
	PGrnCondition condition = {0};

	if (ARR_NDIM(leftOperands) == 0)
		return false;

	condition.isTargets = &(buffers->isTargets);
	GRN_BULK_REWIND(condition.isTargets);
	PGrnConditionDeconstruct(&condition, header);
	if (!condition.query)
		return false;

	return pgroonga_execute_binary_operator_string_array(
		leftOperands, &condition, operator);
}

static bool
pgroonga_execute_binary_operator_in_string(
	const char *leftOperand,
	unsigned int leftOperandSize,
	Datum rightOperands,
	PGrnCondition *condition,
	PGrnBinaryOperatorStringFunction operator)
{
	AnyArrayType *rightOperandsArray = DatumGetAnyArrayP(rightOperands);
	int i, n;

	if (AARR_NDIM(rightOperandsArray) == 0)
		return false;

	n = AARR_DIMS(rightOperandsArray)[0];
	for (i = 1; i <= n; i++)
	{
		Datum rightOperandDatum;
		bool isNULL;

		rightOperandDatum = array_get_element(
			rightOperands, 1, &i, -1, -1, false, 'i', &isNULL);
		if (isNULL)
			continue;

		switch (AARR_ELEMTYPE(rightOperandsArray))
		{
		case VARCHAROID:
			condition->query = DatumGetVarCharPP(rightOperandDatum);
			break;
		case TEXTOID:
			condition->query = DatumGetTextPP(rightOperandDatum);
			break;
		default:
			condition->query = NULL;
			break;
		}
		if (!condition->query)
			continue;
		if (operator(leftOperand, leftOperandSize, condition))
			return true;
	}

	return false;
}

static bool
pgroonga_execute_binary_operator_in_string_array(
	Datum leftOperands,
	Datum rightOperands,
	PGrnCondition *condition,
	PGrnBinaryOperatorStringFunction operator)
{
	AnyArrayType *leftOperandsArray = DatumGetAnyArrayP(leftOperands);
	int i, n;

	if (AARR_NDIM(leftOperandsArray) == 0)
		return false;

	n = AARR_DIMS(leftOperandsArray)[0];
	for (i = 1; i <= n; i++)
	{
		Datum leftOperandDatum;
		const char *leftOperand = NULL;
		unsigned int leftOperandSize = 0;
		bool isNULL;

		leftOperandDatum =
			array_get_element(leftOperands, 1, &i, -1, -1, false, 'i', &isNULL);
		if (isNULL)
			continue;

		PGrnPGDatumExtractString(leftOperandDatum,
								 AARR_ELEMTYPE(leftOperandsArray),
								 &leftOperand,
								 &leftOperandSize);
		if (!leftOperand)
			continue;

		if (pgroonga_execute_binary_operator_in_string(leftOperand,
													   leftOperandSize,
													   rightOperands,
													   condition,
													   operator))
			return true;
	}

	return false;
}

static bool
pgroonga_match_term_raw(const char *target,
						unsigned int targetSize,
						PGrnCondition *condition)
{
	if (PGrnPGTextIsEmpty(condition->query))
		return false;

	if (!PGrnPGTextIsEmpty(condition->indexName) &&
		PGrnIsTemporaryIndexSearchAvailable)
	{
		PGrnSequentialSearchSetTargetText(target, targetSize);
		PGrnSequentialSearchSetMatchTerm(condition);
		return PGrnSequentialSearchExecute();
	}
	else
	{
		grn_bool matched;
		grn_obj targetBuffer;
		grn_obj termBuffer;

		GRN_TEXT_INIT(&targetBuffer, GRN_OBJ_DO_SHALLOW_COPY);
		GRN_TEXT_SET(ctx, &targetBuffer, target, targetSize);

		GRN_TEXT_INIT(&termBuffer, GRN_OBJ_DO_SHALLOW_COPY);
		GRN_TEXT_SET(ctx,
					 &termBuffer,
					 VARDATA_ANY(condition->query),
					 VARSIZE_ANY_EXHDR(condition->query));

		matched = grn_operator_exec_match(ctx, &targetBuffer, &termBuffer);

		GRN_OBJ_FIN(ctx, &targetBuffer);
		GRN_OBJ_FIN(ctx, &termBuffer);

		return matched;
	}
}

/**
 * pgroonga_match_term(target text, term text) : bool
 */
Datum
pgroonga_match_term_text(PG_FUNCTION_ARGS)
{
	text *target = PG_GETARG_TEXT_PP(0);
	text *term = PG_GETARG_TEXT_PP(1);
	PGrnCondition condition = {0};
	bool matched;

	condition.query = term;
	matched = pgroonga_match_term_raw(
		VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_match_term(target text[], term text) : bool
 */
Datum
pgroonga_match_term_text_array(PG_FUNCTION_ARGS)
{
	ArrayType *targets = PG_GETARG_ARRAYTYPE_P(0);
	text *term = PG_GETARG_TEXT_PP(1);
	PGrnCondition condition = {0};
	bool matched;

	condition.query = term;
	matched = pgroonga_execute_binary_operator_string_array(
		targets, &condition, pgroonga_match_term_raw);

	PG_RETURN_BOOL(matched);
}

static bool
pgroonga_equal_raw(const char *leftText,
				   unsigned int leftTextSize,
				   PGrnCondition *condition)
{
	grn_bool matched;
	grn_obj leftTextBuffer;
	grn_obj rightTextBuffer;

	GRN_TEXT_INIT(&leftTextBuffer, GRN_OBJ_DO_SHALLOW_COPY);
	GRN_TEXT_SET(ctx, &leftTextBuffer, leftText, leftTextSize);

	GRN_TEXT_INIT(&rightTextBuffer, GRN_OBJ_DO_SHALLOW_COPY);
	GRN_TEXT_SET(ctx,
				 &rightTextBuffer,
				 VARDATA_ANY(condition->query),
				 VARSIZE_ANY_EXHDR(condition->query));

	/* TODO: Use condition->indexName */
	matched = grn_operator_exec_equal(ctx, &leftTextBuffer, &rightTextBuffer);

	GRN_OBJ_FIN(ctx, &leftTextBuffer);
	GRN_OBJ_FIN(ctx, &rightTextBuffer);

	return matched;
}

/**
 * pgroonga_match_term(target varchar, term varchar) : bool
 */
Datum
pgroonga_match_term_varchar(PG_FUNCTION_ARGS)
{
	VarChar *target = PG_GETARG_VARCHAR_PP(0);
	VarChar *term = PG_GETARG_VARCHAR_PP(1);
	PGrnCondition condition = {0};
	bool matched;

	condition.query = term;
	matched = pgroonga_match_term_raw(
		VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_match_term(target varchar[], term varchar) : bool
 */
Datum
pgroonga_match_term_varchar_array(PG_FUNCTION_ARGS)
{
	ArrayType *targets = PG_GETARG_ARRAYTYPE_P(0);
	VarChar *term = PG_GETARG_VARCHAR_PP(1);
	PGrnCondition condition = {0};
	bool matched;

	condition.query = term;
	matched = pgroonga_execute_binary_operator_string_array(
		targets, &condition, pgroonga_match_term_raw);

	PG_RETURN_BOOL(matched);
}

static bool
pgroonga_match_query_raw(const char *target,
						 unsigned int targetSize,
						 PGrnCondition *condition)
{
	PGrnSequentialSearchSetTargetText(target, targetSize);
	PGrnSequentialSearchSetQuery(condition, PGRN_SEQUENTIAL_SEARCH_QUERY);
	return PGrnSequentialSearchExecute();
}

static bool
pgroonga_match_query_string_array_raw(ArrayType *targets,
									  PGrnCondition *condition)
{
	if (ARR_NDIM(targets) == 0)
		return false;

	PGrnSequentialSearchSetTargetTexts(targets, condition);
	PGrnSequentialSearchSetQuery(condition, PGRN_SEQUENTIAL_SEARCH_QUERY);
	return PGrnSequentialSearchExecute();
}

/**
 * pgroonga_match_query(target text, query text) : bool
 */
Datum
pgroonga_match_query_text(PG_FUNCTION_ARGS)
{
	text *target = PG_GETARG_TEXT_PP(0);
	text *query = PG_GETARG_TEXT_PP(1);
	PGrnCondition condition = {0};
	bool matched;

	condition.query = query;
	matched = pgroonga_match_query_raw(
		VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_match_query(targets text[], query text) : bool
 */
Datum
pgroonga_match_query_text_array(PG_FUNCTION_ARGS)
{
	ArrayType *targets = PG_GETARG_ARRAYTYPE_P(0);
	text *query = PG_GETARG_TEXT_PP(1);
	PGrnCondition condition = {0};
	bool matched;

	condition.query = query;
	matched = pgroonga_match_query_string_array_raw(targets, &condition);

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_match_query(target varchar, query varchar) : bool
 */
Datum
pgroonga_match_query_varchar(PG_FUNCTION_ARGS)
{
	VarChar *target = PG_GETARG_VARCHAR_PP(0);
	VarChar *query = PG_GETARG_VARCHAR_PP(1);
	PGrnCondition condition = {0};
	bool matched;

	condition.query = query;
	matched = pgroonga_match_query_raw(
		VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);

	PG_RETURN_BOOL(matched);
}

/**
 * Caller must satisfy the following conditions:
 * * condition->query is not NULL
 * * condition->query is not an empty text
 */
static bool
pgroonga_match_regexp_raw(const char *target,
						  unsigned int targetSize,
						  PGrnCondition *condition)
{
	if (!PGrnPGTextIsEmpty(condition->indexName) &&
		PGrnIsTemporaryIndexSearchAvailable)
	{
		PGrnSequentialSearchSetTargetText(target, targetSize);
		PGrnSequentialSearchSetRegexp(condition);
		return PGrnSequentialSearchExecute();
	}
	else
	{
		grn_bool matched;
		grn_obj targetBuffer;
		grn_obj patternBuffer;

		GRN_TEXT_INIT(&targetBuffer, GRN_OBJ_DO_SHALLOW_COPY);
		GRN_TEXT_SET(ctx, &targetBuffer, target, targetSize);

		GRN_TEXT_INIT(&patternBuffer, GRN_OBJ_DO_SHALLOW_COPY);
		GRN_TEXT_SET(ctx,
					 &patternBuffer,
					 VARDATA_ANY(condition->query),
					 VARSIZE_ANY_EXHDR(condition->query));

		matched = grn_operator_exec_regexp(ctx, &targetBuffer, &patternBuffer);

		GRN_OBJ_FIN(ctx, &targetBuffer);
		GRN_OBJ_FIN(ctx, &patternBuffer);

		return matched;
	}
}

/**
 * pgroonga_match_regexp(target text, pattern text) : bool
 */
Datum
pgroonga_match_regexp_text(PG_FUNCTION_ARGS)
{
	text *target = PG_GETARG_TEXT_PP(0);
	text *pattern = PG_GETARG_TEXT_PP(1);
	PGrnCondition condition = {0};
	bool matched = false;

	if (PGrnPGTextIsEmpty(pattern))
		PG_RETURN_BOOL(false);

	condition.query = pattern;
	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_match_regexp_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_match_regexp_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_match_regexp_varchar(target varchar, pattern varchar) : bool
 */
Datum
pgroonga_match_regexp_varchar(PG_FUNCTION_ARGS)
{
	VarChar *target = PG_GETARG_VARCHAR_PP(0);
	VarChar *pattern = PG_GETARG_VARCHAR_PP(1);
	PGrnCondition condition = {0};
	bool matched = false;

	condition.query = pattern;
	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_match_regexp_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_match_regexp_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/* v2 */
/**
 * pgroonga_match_text(target text, term text) : bool
 */
Datum
pgroonga_match_text(PG_FUNCTION_ARGS)
{
	text *target = PG_GETARG_TEXT_PP(0);
	text *term = PG_GETARG_TEXT_PP(1);
	PGrnCondition condition = {0};
	bool matched = false;

	condition.query = term;
	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_match_term_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_match_term_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

static bool
pgroonga_match_condition_raw(const char *target,
							 unsigned int targetSize,
							 HeapTupleHeader header)
{
	PGrnCondition condition = {0};

	condition.isTargets = &(buffers->isTargets);
	GRN_BULK_REWIND(condition.isTargets);
	PGrnConditionDeconstruct(&condition, header);
	if (!condition.query)
		return false;

	if (GRN_BULK_VSIZE(condition.isTargets) > 0 &&
		!GRN_BOOL_VALUE_AT(condition.isTargets, 0))
		return false;

	return pgroonga_match_term_raw(target, targetSize, &condition);
}

/**
 * pgroonga_match_text_condition(target text,
 *                               condition pgroonga_condition) : bool
 *
 * Deprecated:
 * pgroonga_match_text_condition(
 *     target text,
 *     condition pgroonga_full_text_search_condition) : bool
 *
 * Deprecated:
 * pgroonga_match_text_condition(
 *     target text,
 *     condition pgroonga_full_text_search_condition_with_scorers) : bool
 */
Datum
pgroonga_match_text_condition(PG_FUNCTION_ARGS)
{
	text *target = PG_GETARG_TEXT_PP(0);
	HeapTupleHeader header = PG_GETARG_HEAPTUPLEHEADER(1);
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_match_condition_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), header);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_match_condition_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), header);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_match_text_condition_with_scorers(
 *     target text,
 *     condition pgroonga_full_text_search_condition_with_scorers) : bool
 *
 * It's deprecated since 3.1.6. Just for backward compatibility.
 */
Datum
pgroonga_match_text_condition_with_scorers(PG_FUNCTION_ARGS)
{
	return pgroonga_match_text_condition(fcinfo);
}

/**
 * pgroonga_match_text_array(targets text[], term text) : bool
 */
Datum
pgroonga_match_text_array(PG_FUNCTION_ARGS)
{
	ArrayType *targets = PG_GETARG_ARRAYTYPE_P(0);
	text *term = PG_GETARG_TEXT_PP(1);
	PGrnCondition condition = {0};
	bool matched = false;

	condition.query = term;
	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_execute_binary_operator_string_array(
			targets, &condition, pgroonga_match_term_raw);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_execute_binary_operator_string_array(
			targets, &condition, pgroonga_match_term_raw);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_match_text_array_condition(targets text[],
 *                                     condition pgroonga_condition) : bool
 *
 * Deprecated:
 * pgroonga_match_text_array_condition(
 *     targets text[],
 *     condition pgroonga_full_text_search_condition) : bool
 *
 * Deprecated:
 * pgroonga_match_text_array_condition(
 *     targets text[],
 *     condition pgroonga_full_text_search_condition_with_scorers) : bool
 *
 * It's deprecated since 3.1.6. Just for backward compatibility.
 */
Datum
pgroonga_match_text_array_condition(PG_FUNCTION_ARGS)
{
	ArrayType *targets = PG_GETARG_ARRAYTYPE_P(0);
	HeapTupleHeader header = PG_GETARG_HEAPTUPLEHEADER(1);
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_execute_binary_operator_string_array_condition_raw(
			targets, header, pgroonga_match_term_raw);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_execute_binary_operator_string_array_condition_raw(
			targets, header, pgroonga_match_term_raw);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_match_text_array_condition_with_scorers(
 *     targets text[],
 *     condition pgroonga_full_text_search_condition_with_scorers) : bool
 *
 * It's deprecated since 3.1.6. Just for backward compatibility.
 */
Datum
pgroonga_match_text_array_condition_with_scorers(PG_FUNCTION_ARGS)
{
	return pgroonga_match_text_array_condition(fcinfo);
}

/**
 * pgroonga_match_varchar(target varchar, term varchar) : bool
 */
Datum
pgroonga_match_varchar(PG_FUNCTION_ARGS)
{
	VarChar *target = PG_GETARG_VARCHAR_PP(0);
	VarChar *term = PG_GETARG_VARCHAR_PP(1);
	PGrnCondition condition = {0};
	bool matched = false;

	condition.query = term;
	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_match_term_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_match_term_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_match_varchar_condition(target varchar,
 *                                  condition pgroonga_condition) : bool
 *
 * Deprecated:
 * pgroonga_match_varchar_condition(
 *     target varchar,
 *     condition pgroonga_full_text_search_condition) : bool
 *
 * Deprecated:
 * pgroonga_match_varchar_condition(
 *     target varchar,
 *     condition pgroonga_full_text_search_condition_with_scorers) : bool
 */
Datum
pgroonga_match_varchar_condition(PG_FUNCTION_ARGS)
{
	VarChar *target = PG_GETARG_VARCHAR_PP(0);
	HeapTupleHeader header = PG_GETARG_HEAPTUPLEHEADER(1);
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_match_condition_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), header);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_match_condition_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), header);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_match_varchar_condition_with_scorers(
 *   target varchar,
 *   condition pgroonga_full_text_search_condition_with_scorers) : bool
 */
Datum
pgroonga_match_varchar_condition_with_scorers(PG_FUNCTION_ARGS)
{
	return pgroonga_match_varchar_condition(fcinfo);
}

/**
 * pgroonga_contain_varchar_array(target varchar[], term varchar) : bool
 */
Datum
pgroonga_contain_varchar_array(PG_FUNCTION_ARGS)
{
	ArrayType *targets = PG_GETARG_ARRAYTYPE_P(0);
	VarChar *term = PG_GETARG_VARCHAR_PP(1);
	PGrnCondition condition = {0};
	bool matched = false;

	condition.query = term;
	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_execute_binary_operator_string_array(
			targets, &condition, pgroonga_equal_raw);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_execute_binary_operator_string_array(
			targets, &condition, pgroonga_equal_raw);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_query_text(target text, query text) : bool
 */
Datum
pgroonga_query_text(PG_FUNCTION_ARGS)
{
	text *target = PG_GETARG_TEXT_PP(0);
	text *query = PG_GETARG_TEXT_PP(1);
	PGrnCondition condition = {0};
	bool matched = false;

	condition.query = query;
	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_match_query_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_match_query_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

static bool
pgroonga_query_condition_raw(const char *target,
							 unsigned int targetSize,
							 HeapTupleHeader header)
{
	PGrnCondition condition = {0};

	condition.isTargets = &(buffers->isTargets);
	GRN_BULK_REWIND(condition.isTargets);
	PGrnConditionDeconstruct(&condition, header);
	if (!condition.query)
		return false;

	if (GRN_BULK_VSIZE(condition.isTargets) > 0 &&
		!GRN_BOOL_VALUE_AT(condition.isTargets, 0))
		return false;

	return pgroonga_match_query_raw(target, targetSize, &condition);
}

/**
 * pgroonga_query_text_condition(target text,
 *                               condition pgroonga_condition) : bool
 *
 * Deprecated:
 * pgroonga_query_text_condition(
 *     target text,
 *     condition pgroonga_full_text_search_condition) : bool
 *
 * Deprecated:
 * pgroonga_query_text_condition(
 *     target text,
 *     condition pgroonga_full_text_search_condition_with_scorers) : bool
 */
Datum
pgroonga_query_text_condition(PG_FUNCTION_ARGS)
{
	text *target = PG_GETARG_TEXT_PP(0);
	HeapTupleHeader header = PG_GETARG_HEAPTUPLEHEADER(1);
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_query_condition_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), header);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_query_condition_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), header);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_query_text_condition_with_scorers(
 *     target text,
 *     condition pgroonga_full_text_search_condition_with_scorers) : bool
 *
 * It's deprecated since 3.1.6. Just for backward compatibility.
 */
Datum
pgroonga_query_text_condition_with_scorers(PG_FUNCTION_ARGS)
{
	return pgroonga_query_text_condition(fcinfo);
}

/**
 * pgroonga_query_text_array(targets text[], query text) : bool
 */
Datum
pgroonga_query_text_array(PG_FUNCTION_ARGS)
{
	ArrayType *targets = PG_GETARG_ARRAYTYPE_P(0);
	text *query = PG_GETARG_TEXT_PP(1);
	PGrnCondition condition = {0};
	bool matched = false;

	condition.query = query;
	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_match_query_string_array_raw(targets, &condition);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_match_query_string_array_raw(targets, &condition);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

static bool
pgroonga_query_text_array_condition_raw(ArrayType *targets,
										HeapTupleHeader header)
{
	PGrnCondition condition = {0};

	condition.isTargets = &(buffers->isTargets);
	GRN_BULK_REWIND(condition.isTargets);
	PGrnConditionDeconstruct(&condition, header);
	if (!condition.query)
		return false;

	return pgroonga_match_query_string_array_raw(targets, &condition);
}

/**
 * pgroonga_query_text_array_condition(targets text[],
 *                                     condition pgroonga_condition) : bool
 *
 * Deprecated:
 * pgroonga_query_text_array_condition(
 *     targets text[],
 *     condition pgroonga_full_text_search_condition) : bool
 *
 * Deprecated:
 * pgroonga_query_text_array_condition(
 *     targets text[],
 *     condition pgroonga_full_text_search_condition_with_scorers) : bool
 */
Datum
pgroonga_query_text_array_condition(PG_FUNCTION_ARGS)
{
	ArrayType *targets = PG_GETARG_ARRAYTYPE_P(0);
	HeapTupleHeader header = PG_GETARG_HEAPTUPLEHEADER(1);
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_query_text_array_condition_raw(targets, header);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_query_text_array_condition_raw(targets, header);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_query_text_array_condition_with_scorers(
 *     targets text[],
 *     condition pgroonga_full_text_search_condition_with_scorers) : bool
 *
 * It's deprecated since 3.1.6. Just for backward compatibility.
 */
Datum
pgroonga_query_text_array_condition_with_scorers(PG_FUNCTION_ARGS)
{
	return pgroonga_query_text_array_condition(fcinfo);
}

/**
 * pgroonga_query_varchar(target varchar, term varchar) : bool
 */
Datum
pgroonga_query_varchar(PG_FUNCTION_ARGS)
{
	VarChar *target = PG_GETARG_VARCHAR_PP(0);
	VarChar *query = PG_GETARG_VARCHAR_PP(1);
	PGrnCondition condition = {0};
	bool matched = false;

	condition.query = query;
	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_match_query_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_match_query_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_query_varchar_condition(target varchar,
 *                                  condition pgroonga_condition) : bool
 *
 * Deprecated:
 * pgroonga_query_varchar_condition(
 *     target varchar,
 *     condition pgroonga_full_text_search_condition) : bool
 *
 * Deprecated:
 * pgroonga_query_varchar_condition(
 *     target varchar,
 *     condition pgroonga_full_text_search_condition) : bool
 */
Datum
pgroonga_query_varchar_condition(PG_FUNCTION_ARGS)
{
	VarChar *target = PG_GETARG_VARCHAR_PP(0);
	HeapTupleHeader header = PG_GETARG_HEAPTUPLEHEADER(1);
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_query_condition_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), header);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_query_condition_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), header);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_query_varchar_condition_with_scorers(
 *     target varchar,
 *     condition pgroonga_full_text_search_condition_with_scorers) : bool
 *
 * It's deprecated since 3.1.6. Just for backward compatibility.
 */
Datum
pgroonga_query_varchar_condition_with_scorers(PG_FUNCTION_ARGS)
{
	return pgroonga_query_varchar_condition(fcinfo);
}

/**
 * pgroonga_similar_text(target text, document text) : bool
 */
Datum
pgroonga_similar_text(PG_FUNCTION_ARGS)
{
	const char *tag = "[similar][text]";
	PGrnCheckRC(GRN_FUNCTION_NOT_IMPLEMENTED,
				"%s similar search available only in index scan",
				tag);

	PG_RETURN_BOOL(false);
}

/**
 * pgroonga_similar_text_array(targets text[], document text) : bool
 */
Datum
pgroonga_similar_text_array(PG_FUNCTION_ARGS)
{
	const char *tag = "[similar][text-array]";
	PGrnCheckRC(GRN_FUNCTION_NOT_IMPLEMENTED,
				"%s similar search is available only in index scan",
				tag);

	PG_RETURN_BOOL(false);
}

/**
 * pgroonga_similar_varchar(target varchar, document varchar) : bool
 */
Datum
pgroonga_similar_varchar(PG_FUNCTION_ARGS)
{
	const char *tag = "[similar][varchar]";
	PGrnCheckRC(GRN_FUNCTION_NOT_IMPLEMENTED,
				"%s similar search is available only in index scan",
				tag);

	PG_RETURN_BOOL(false);
}

/**
 * pgroonga_similar_text_condition(query text, condition pgroonga_condition) :
 * bool
 */
Datum
pgroonga_similar_text_condition(PG_FUNCTION_ARGS)
{
	const char *tag = "[similar][text][condition]";
	PGrnCheckRC(GRN_FUNCTION_NOT_IMPLEMENTED,
				"%s similar search available only in index scan",
				tag);

	PG_RETURN_BOOL(false);
}

/**
 * pgroonga_similar_distance_text_condition(query text, condition
 * pgroonga_condition) : float8
 */
Datum
pgroonga_similar_distance_text_condition(PG_FUNCTION_ARGS)
{
	/* We want to raise an exception here because we handle sorting by
	 * distance in index scan but PostgreSQL calls this even if we
	 * use index scan. So we always return a dummy value. */

	/* const char *tag = "[similar][text][distance][condition]"; */
	/* PGrnCheckRC(GRN_FUNCTION_NOT_IMPLEMENTED, */
	/* 			"%s similar distance available only in index scan", */
	/* 			tag); */

	PG_RETURN_FLOAT8(0.0);
}

/**
 * pgroonga_script_text(target text, script text) : bool
 */
Datum
pgroonga_script_text(PG_FUNCTION_ARGS)
{
	const char *tag = "[script][text]";
	PGrnCheckRC(GRN_FUNCTION_NOT_IMPLEMENTED,
				"%s script syntax search is available only in index scan",
				tag);

	PG_RETURN_BOOL(false);
}

/**
 * pgroonga_script_text_array(targets text[], script text) : bool
 */
Datum
pgroonga_script_text_array(PG_FUNCTION_ARGS)
{
	const char *tag = "[script][text-array]";
	PGrnCheckRC(GRN_FUNCTION_NOT_IMPLEMENTED,
				"%s script syntax search is available only in index scan",
				tag);

	PG_RETURN_BOOL(false);
}

/**
 * pgroonga_script_varchar(target varchar, script varchar) : bool
 */
Datum
pgroonga_script_varchar(PG_FUNCTION_ARGS)
{
	const char *tag = "[script][varchar]";
	PGrnCheckRC(GRN_FUNCTION_NOT_IMPLEMENTED,
				"%s script syntax search is available only in index scan",
				tag);

	PG_RETURN_BOOL(false);
}

static bool
pgroonga_prefix_raw(const char *text,
					unsigned int textSize,
					PGrnCondition *condition)
{
	if (PGrnPGTextIsEmpty(condition->query))
		return false;

	if (!PGrnPGTextIsEmpty(condition->indexName) &&
		PGrnIsTemporaryIndexSearchAvailable)
	{
		PGrnSequentialSearchSetTargetText(text, textSize);
		PGrnSequentialSearchSetPrefix(condition);
		return PGrnSequentialSearchExecute();
	}
	else
	{
		grn_bool matched;
		grn_obj targetBuffer;
		grn_obj prefixBuffer;

		GRN_TEXT_INIT(&targetBuffer, GRN_OBJ_DO_SHALLOW_COPY);
		GRN_TEXT_SET(ctx, &targetBuffer, text, textSize);

		GRN_TEXT_INIT(&prefixBuffer, GRN_OBJ_DO_SHALLOW_COPY);
		GRN_TEXT_SET(ctx,
					 &prefixBuffer,
					 VARDATA_ANY(condition->query),
					 VARSIZE_ANY_EXHDR(condition->query));

		matched = grn_operator_exec_prefix(ctx, &targetBuffer, &prefixBuffer);

		GRN_OBJ_FIN(ctx, &targetBuffer);
		GRN_OBJ_FIN(ctx, &prefixBuffer);

		return matched;
	}
}

/**
 * pgroonga_prefix_text(target text, prefix text) : bool
 */
Datum
pgroonga_prefix_text(PG_FUNCTION_ARGS)
{
	text *target = PG_GETARG_TEXT_PP(0);
	text *prefix = PG_GETARG_TEXT_PP(1);
	PGrnCondition condition = {0};
	bool matched = false;

	condition.query = prefix;
	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_prefix_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_prefix_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

static bool
pgroonga_prefix_condition_raw(const char *target,
							  unsigned int targetSize,
							  HeapTupleHeader header)
{
	PGrnCondition condition = {0};

	condition.isTargets = &(buffers->isTargets);
	GRN_BULK_REWIND(condition.isTargets);
	PGrnConditionDeconstruct(&condition, header);

	if (!condition.query)
		return false;

	if (GRN_BULK_VSIZE(condition.isTargets) > 0 &&
		!GRN_BOOL_VALUE_AT(condition.isTargets, 0))
		return false;

	return pgroonga_prefix_raw(target, targetSize, &condition);
}

/**
 * pgroonga_prefix_text_condition(
 *   target text,
 *   condition pgroonga_full_text_search_condition
 * ) : bool
 */
Datum
pgroonga_prefix_text_condition(PG_FUNCTION_ARGS)
{
	text *target = PG_GETARG_TEXT_PP(0);
	HeapTupleHeader header = PG_GETARG_HEAPTUPLEHEADER(1);
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_prefix_condition_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), header);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_prefix_condition_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), header);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_prefix_text_array(targets text[], prefix text) : bool
 */
Datum
pgroonga_prefix_text_array(PG_FUNCTION_ARGS)
{
	ArrayType *targets = PG_GETARG_ARRAYTYPE_P(0);
	text *prefix = PG_GETARG_TEXT_PP(1);
	PGrnCondition condition = {0};
	bool matched = false;

	condition.query = prefix;
	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_execute_binary_operator_string_array(
			targets, &condition, pgroonga_prefix_raw);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_execute_binary_operator_string_array(
			targets, &condition, pgroonga_prefix_raw);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_prefix_text_array_condition(
 *   targets text[],
 *   condition pgroonga_condition
 * ) : bool
 */
Datum
pgroonga_prefix_text_array_condition(PG_FUNCTION_ARGS)
{
	ArrayType *targets = PG_GETARG_ARRAYTYPE_P(0);
	HeapTupleHeader header = PG_GETARG_HEAPTUPLEHEADER(1);
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_execute_binary_operator_string_array_condition_raw(
			targets, header, pgroonga_prefix_raw);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_execute_binary_operator_string_array_condition_raw(
			targets, header, pgroonga_prefix_raw);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_prefix_varchar(target varchar, prefix varchar) : bool
 */
Datum
pgroonga_prefix_varchar(PG_FUNCTION_ARGS)
{
	VarChar *target = PG_GETARG_VARCHAR_PP(0);
	VarChar *prefix = PG_GETARG_VARCHAR_PP(1);
	PGrnCondition condition = {0};
	bool matched = false;

	condition.query = prefix;
	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_prefix_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_prefix_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_prefix_varchar_condition(
 *   target varchar,
 *   condition pgroonga_full_text_search_condition
 * ) : bool
 */
Datum
pgroonga_prefix_varchar_condition(PG_FUNCTION_ARGS)
{
	VarChar *target = PG_GETARG_VARCHAR_PP(0);
	HeapTupleHeader header = PG_GETARG_HEAPTUPLEHEADER(1);
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_prefix_condition_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), header);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_prefix_condition_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), header);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_prefix_varchar_array(targets varchar[], prefix varchar) : bool
 */
Datum
pgroonga_prefix_varchar_array(PG_FUNCTION_ARGS)
{
	ArrayType *targets = PG_GETARG_ARRAYTYPE_P(0);
	VarChar *prefix = PG_GETARG_VARCHAR_PP(1);
	PGrnCondition condition = {0};
	bool matched = false;

	condition.query = prefix;
	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_execute_binary_operator_string_array(
			targets, &condition, pgroonga_prefix_raw);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_execute_binary_operator_string_array(
			targets, &condition, pgroonga_prefix_raw);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_prefix_varchar_array_condition(
 *   targets varchar[],
 *   condition pgroonga_condition
 * ) : bool
 */
Datum
pgroonga_prefix_varchar_array_condition(PG_FUNCTION_ARGS)
{
	ArrayType *targets = PG_GETARG_ARRAYTYPE_P(0);
	HeapTupleHeader header = PG_GETARG_HEAPTUPLEHEADER(1);
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_execute_binary_operator_string_array_condition_raw(
			targets, header, pgroonga_prefix_raw);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_execute_binary_operator_string_array_condition_raw(
			targets, header, pgroonga_prefix_raw);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_prefix_contain_text_array(targets text[], prefix text) : bool
 *
 * It's deprecated since 1.2.1. Just for backward compatibility.
 */
Datum
pgroonga_prefix_contain_text_array(PG_FUNCTION_ARGS)
{
	return pgroonga_prefix_text_array(fcinfo);
}

static bool
pgroonga_prefix_rk_raw(const char *text,
					   unsigned int textSize,
					   PGrnCondition *condition)
{
	const char *tag = "[prefix-rk]";
	grn_obj *expression;
	grn_obj *variable;
	bool matched;
	grn_id id;

	if (!condition->query)
		return false;

	/* TODO: Use condition->indexName */

	GRN_EXPR_CREATE_FOR_QUERY(
		ctx, prefixRKSequentialSearchData.table, expression, variable);
	if (!expression)
	{
		PGrnCheckRC(
			GRN_NO_MEMORY_AVAILABLE, "%s failed to create expression", tag);
	}

	PGrnExprAppendObject(expression,
						 grn_ctx_get(ctx, "prefix_rk_search", -1),
						 GRN_OP_PUSH,
						 1,
						 tag,
						 NULL);
	PGrnExprAppendObject(expression,
						 prefixRKSequentialSearchData.key,
						 GRN_OP_GET_VALUE,
						 1,
						 tag,
						 NULL);
	PGrnExprAppendConstString(expression,
							  VARDATA_ANY(condition->query),
							  VARSIZE_ANY_EXHDR(condition->query),
							  GRN_OP_PUSH,
							  1,
							  tag);
	PGrnExprAppendOp(expression, GRN_OP_CALL, 2, tag, NULL);

	id = grn_table_add(
		ctx, prefixRKSequentialSearchData.table, text, textSize, NULL);
	grn_table_select(ctx,
					 prefixRKSequentialSearchData.table,
					 expression,
					 prefixRKSequentialSearchData.resultTable,
					 GRN_OP_OR);
	matched = grn_table_size(ctx, prefixRKSequentialSearchData.resultTable) > 0;
	grn_table_delete(
		ctx, prefixRKSequentialSearchData.resultTable, &id, sizeof(grn_id));
	grn_table_delete(ctx, prefixRKSequentialSearchData.table, text, textSize);

	grn_obj_close(ctx, expression);

	return matched;
}

/**
 * pgroonga_prefix_rk_text(target text, prefix text) : bool
 */
Datum
pgroonga_prefix_rk_text(PG_FUNCTION_ARGS)
{
	text *target = PG_GETARG_TEXT_PP(0);
	text *prefix = PG_GETARG_TEXT_PP(1);
	PGrnCondition condition = {0};
	bool matched = false;

	condition.query = prefix;
	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_prefix_rk_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_prefix_rk_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_prefix_rk_text_array(targets text[], prefix text) : bool
 */
Datum
pgroonga_prefix_rk_text_array(PG_FUNCTION_ARGS)
{
	ArrayType *targets = PG_GETARG_ARRAYTYPE_P(0);
	text *prefix = PG_GETARG_TEXT_PP(1);
	PGrnCondition condition = {0};
	bool matched = false;

	condition.query = prefix;
	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_execute_binary_operator_string_array(
			targets, &condition, pgroonga_prefix_rk_raw);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_execute_binary_operator_string_array(
			targets, &condition, pgroonga_prefix_rk_raw);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_prefix_rk_varchar(target varchar, prefix varchar) : bool
 */
Datum
pgroonga_prefix_rk_varchar(PG_FUNCTION_ARGS)
{
	VarChar *target = PG_GETARG_VARCHAR_PP(0);
	VarChar *prefix = PG_GETARG_VARCHAR_PP(1);
	PGrnCondition condition = {0};
	bool matched = false;

	condition.query = prefix;
	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_prefix_rk_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_prefix_rk_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_prefix_rk_varchar_array(targets varchar[], prefix varchar) : bool
 */
Datum
pgroonga_prefix_rk_varchar_array(PG_FUNCTION_ARGS)
{
	ArrayType *targets = PG_GETARG_ARRAYTYPE_P(0);
	VarChar *prefix = PG_GETARG_VARCHAR_PP(1);
	PGrnCondition condition = {0};
	bool matched = false;

	condition.query = prefix;
	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_execute_binary_operator_string_array(
			targets, &condition, pgroonga_prefix_rk_raw);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_execute_binary_operator_string_array(
			targets, &condition, pgroonga_prefix_rk_raw);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_prefix_rk_contain_text_array(targets text[], prefix text) : bool
 *
 * It's deprecated since 1.2.1. Just for backward compatibility.
 */
Datum
pgroonga_prefix_rk_contain_text_array(PG_FUNCTION_ARGS)
{
	return pgroonga_prefix_rk_text_array(fcinfo);
}

/**
 * pgroonga_match_in_text(target text, keywords text[]) : bool
 */
Datum
pgroonga_match_in_text(PG_FUNCTION_ARGS)
{
	text *target = PG_GETARG_TEXT_PP(0);
	Datum keywords = PG_GETARG_DATUM(1);
	PGrnCondition condition = {0};
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_execute_binary_operator_in_string(
			VARDATA_ANY(target),
			VARSIZE_ANY_EXHDR(target),
			keywords,
			&condition,
			pgroonga_match_term_raw);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_execute_binary_operator_in_string(
			VARDATA_ANY(target),
			VARSIZE_ANY_EXHDR(target),
			keywords,
			&condition,
			pgroonga_match_term_raw);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_match_contain_text(target text, keywords text[]) : bool
 *
 * It's deprecated since 1.2.1. Just for backward compatibility.
 */
Datum
pgroonga_match_contain_text(PG_FUNCTION_ARGS)
{
	return pgroonga_match_in_text(fcinfo);
}

/**
 * pgroonga_match_in_text_array(targets text[], keywords text[]) : bool
 */
Datum
pgroonga_match_in_text_array(PG_FUNCTION_ARGS)
{
	Datum targets = PG_GETARG_DATUM(0);
	Datum keywords = PG_GETARG_DATUM(1);
	PGrnCondition condition = {0};
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_execute_binary_operator_in_string_array(
			targets, keywords, &condition, pgroonga_match_term_raw);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_execute_binary_operator_in_string_array(
			targets, keywords, &condition, pgroonga_match_term_raw);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_match_in_varchar(target varchar, keywords varchar[]) : bool
 */
Datum
pgroonga_match_in_varchar(PG_FUNCTION_ARGS)
{
	VarChar *target = PG_GETARG_VARCHAR_PP(0);
	Datum keywords = PG_GETARG_DATUM(1);
	PGrnCondition condition = {0};
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_execute_binary_operator_in_string(
			VARDATA_ANY(target),
			VARSIZE_ANY_EXHDR(target),
			keywords,
			&condition,
			pgroonga_match_term_raw);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_execute_binary_operator_in_string(
			VARDATA_ANY(target),
			VARSIZE_ANY_EXHDR(target),
			keywords,
			&condition,
			pgroonga_match_term_raw);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_query_in_text(target text, queries text[]) : bool
 */
Datum
pgroonga_query_in_text(PG_FUNCTION_ARGS)
{
	text *target = PG_GETARG_TEXT_PP(0);
	Datum queries = PG_GETARG_DATUM(1);
	PGrnCondition condition = {0};
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_execute_binary_operator_in_string(
			VARDATA_ANY(target),
			VARSIZE_ANY_EXHDR(target),
			queries,
			&condition,
			pgroonga_match_query_raw);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_execute_binary_operator_in_string(
			VARDATA_ANY(target),
			VARSIZE_ANY_EXHDR(target),
			queries,
			&condition,
			pgroonga_match_query_raw);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_query_in_text(target text, queries text[]) : bool
 *
 * It's deprecated since 1.2.1. Just for backward compatibility.
 */
Datum
pgroonga_query_contain_text(PG_FUNCTION_ARGS)
{
	return pgroonga_query_in_text(fcinfo);
}

/**
 * pgroonga_query_in_text_array(targets text[], queries text[]) : bool
 */
Datum
pgroonga_query_in_text_array(PG_FUNCTION_ARGS)
{
	Datum targets = PG_GETARG_DATUM(0);
	Datum queries = PG_GETARG_DATUM(1);
	PGrnCondition condition = {0};
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_execute_binary_operator_in_string_array(
			targets, queries, &condition, pgroonga_match_query_raw);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_execute_binary_operator_in_string_array(
			targets, queries, &condition, pgroonga_match_query_raw);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_query_in_varchar(target varchar, queries varchar[]) : bool
 */
Datum
pgroonga_query_in_varchar(PG_FUNCTION_ARGS)
{
	VarChar *target = PG_GETARG_VARCHAR_PP(0);
	Datum queries = PG_GETARG_DATUM(1);
	PGrnCondition condition = {0};
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_execute_binary_operator_in_string(
			VARDATA_ANY(target),
			VARSIZE_ANY_EXHDR(target),
			queries,
			&condition,
			pgroonga_match_query_raw);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_execute_binary_operator_in_string(
			VARDATA_ANY(target),
			VARSIZE_ANY_EXHDR(target),
			queries,
			&condition,
			pgroonga_match_query_raw);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_prefix_in_text(target text, prefixes text[]) : bool
 */
Datum
pgroonga_prefix_in_text(PG_FUNCTION_ARGS)
{
	text *target = PG_GETARG_TEXT_PP(0);
	Datum prefixes = PG_GETARG_DATUM(1);
	PGrnCondition condition = {0};
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_execute_binary_operator_in_string(
			VARDATA_ANY(target),
			VARSIZE_ANY_EXHDR(target),
			prefixes,
			&condition,
			pgroonga_prefix_raw);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_execute_binary_operator_in_string(
			VARDATA_ANY(target),
			VARSIZE_ANY_EXHDR(target),
			prefixes,
			&condition,
			pgroonga_prefix_raw);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_not_prefix_in_text(target text, prefixes text[]) : bool
 */
Datum
pgroonga_not_prefix_in_text(PG_FUNCTION_ARGS)
{
	text *target = PG_GETARG_TEXT_PP(0);
	Datum prefixes = PG_GETARG_DATUM(1);
	PGrnCondition condition = {0};
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_execute_binary_operator_in_string(
			VARDATA_ANY(target),
			VARSIZE_ANY_EXHDR(target),
			prefixes,
			&condition,
			pgroonga_prefix_raw);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_execute_binary_operator_in_string(
			VARDATA_ANY(target),
			VARSIZE_ANY_EXHDR(target),
			prefixes,
			&condition,
			pgroonga_prefix_raw);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(!matched);
}

/**
 * pgroonga_prefix_in_text_array(targets text[], prefixes text[]) : bool
 */
Datum
pgroonga_prefix_in_text_array(PG_FUNCTION_ARGS)
{
	Datum targets = PG_GETARG_DATUM(0);
	Datum prefixes = PG_GETARG_DATUM(1);
	PGrnCondition condition = {0};
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_execute_binary_operator_in_string_array(
			targets, prefixes, &condition, pgroonga_prefix_raw);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_execute_binary_operator_in_string_array(
			targets, prefixes, &condition, pgroonga_prefix_raw);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_prefix_in_varchar(target varchar, prefixes varchar[]) : bool
 */
Datum
pgroonga_prefix_in_varchar(PG_FUNCTION_ARGS)
{
	VarChar *target = PG_GETARG_VARCHAR_PP(0);
	Datum prefixes = PG_GETARG_DATUM(1);
	PGrnCondition condition = {0};
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_execute_binary_operator_in_string(
			VARDATA_ANY(target),
			VARSIZE_ANY_EXHDR(target),
			prefixes,
			&condition,
			pgroonga_prefix_raw);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_execute_binary_operator_in_string(
			VARDATA_ANY(target),
			VARSIZE_ANY_EXHDR(target),
			prefixes,
			&condition,
			pgroonga_prefix_raw);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_prefix_in_varchar_array(targets varchar[], prefixes varchar[]) :
 * bool
 */
Datum
pgroonga_prefix_in_varchar_array(PG_FUNCTION_ARGS)
{
	Datum targets = PG_GETARG_DATUM(0);
	Datum prefixes = PG_GETARG_DATUM(1);
	PGrnCondition condition = {0};
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_execute_binary_operator_in_string_array(
			targets, prefixes, &condition, pgroonga_prefix_raw);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_execute_binary_operator_in_string_array(
			targets, prefixes, &condition, pgroonga_prefix_raw);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_prefix_rk_in_text(target text, prefixes text[]) : bool
 */
Datum
pgroonga_prefix_rk_in_text(PG_FUNCTION_ARGS)
{
	text *target = PG_GETARG_TEXT_PP(0);
	Datum prefixes = PG_GETARG_DATUM(1);
	PGrnCondition condition = {0};
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_execute_binary_operator_in_string(
			VARDATA_ANY(target),
			VARSIZE_ANY_EXHDR(target),
			prefixes,
			&condition,
			pgroonga_prefix_rk_raw);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_execute_binary_operator_in_string(
			VARDATA_ANY(target),
			VARSIZE_ANY_EXHDR(target),
			prefixes,
			&condition,
			pgroonga_prefix_rk_raw);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_prefix_rk_in_text_array(targets text[], prefixes text[]) : bool
 */
Datum
pgroonga_prefix_rk_in_text_array(PG_FUNCTION_ARGS)
{
	Datum targets = PG_GETARG_DATUM(0);
	Datum prefixes = PG_GETARG_DATUM(1);
	PGrnCondition condition = {0};
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_execute_binary_operator_in_string_array(
			targets, prefixes, &condition, pgroonga_prefix_rk_raw);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_execute_binary_operator_in_string_array(
			targets, prefixes, &condition, pgroonga_prefix_rk_raw);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_prefix_rk_in_varchar(target varchar, prefixes varchar[]) : bool
 */
Datum
pgroonga_prefix_rk_in_varchar(PG_FUNCTION_ARGS)
{
	VarChar *target = PG_GETARG_VARCHAR_PP(0);
	Datum prefixes = PG_GETARG_DATUM(1);
	PGrnCondition condition = {0};
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_execute_binary_operator_in_string(
			VARDATA_ANY(target),
			VARSIZE_ANY_EXHDR(target),
			prefixes,
			&condition,
			pgroonga_prefix_rk_raw);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_execute_binary_operator_in_string(
			VARDATA_ANY(target),
			VARSIZE_ANY_EXHDR(target),
			prefixes,
			&condition,
			pgroonga_prefix_rk_raw);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_prefix_rk_in_varchar_array(targets varchar[], prefixes varchar[]) :
 * bool
 */
Datum
pgroonga_prefix_rk_in_varchar_array(PG_FUNCTION_ARGS)
{
	Datum targets = PG_GETARG_DATUM(0);
	Datum prefixes = PG_GETARG_DATUM(1);
	PGrnCondition condition = {0};
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_execute_binary_operator_in_string_array(
			targets, prefixes, &condition, pgroonga_prefix_rk_raw);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_execute_binary_operator_in_string_array(
			targets, prefixes, &condition, pgroonga_prefix_rk_raw);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_regexp_text(target text, pattern text) : bool
 */
Datum
pgroonga_regexp_text(PG_FUNCTION_ARGS)
{
	text *target = PG_GETARG_TEXT_PP(0);
	text *pattern = PG_GETARG_TEXT_PP(1);
	PGrnCondition condition = {0};
	bool matched = false;

	if (PGrnPGTextIsEmpty(pattern))
		PG_RETURN_BOOL(false);

	condition.query = pattern;
	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_match_regexp_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_match_regexp_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * Caller must satisfy the following conditions:
 * * targets is not empty
 * * pattern is not NULL
 * * pattern is not an empty text
 */
static bool
pgroonga_match_regexp_text_array_raw(ArrayType *targets,
									 PGrnCondition *condition)
{
	bool matched = false;
	ArrayIterator iterator = array_create_iterator(targets, 0, NULL);
	Datum datum;
	bool isNULL;

	while (array_iterate(iterator, &datum, &isNULL))
	{
		const char *target = NULL;
		unsigned int targetSize = 0;

		if (isNULL)
			continue;

		PGrnPGDatumExtractString(
			datum, ARR_ELEMTYPE(targets), &target, &targetSize);
		if (!target)
			continue;

		if (pgroonga_match_regexp_raw(target, targetSize, condition))
		{
			matched = true;
			break;
		}
	}
	array_free_iterator(iterator);

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_regexp_text_array(targets text[], pattern text) : bool
 */
Datum
pgroonga_regexp_text_array(PG_FUNCTION_ARGS)
{
	ArrayType *targets = PG_GETARG_ARRAYTYPE_P(0);
	text *pattern = PG_GETARG_TEXT_PP(1);
	bool matched = false;
	PGrnCondition condition = {0};

	if (ARR_NDIM(targets) == 0)
		PG_RETURN_BOOL(false);
	if (PGrnPGTextIsEmpty(pattern))
		PG_RETURN_BOOL(false);
	condition.query = pattern;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_match_regexp_text_array_raw(targets, &condition);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_match_regexp_text_array_raw(targets, &condition);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_regexp_text_array_condition(targets text[],
 *                                      condition pgroonga_condition) : bool
 */
Datum
pgroonga_regexp_text_array_condition(PG_FUNCTION_ARGS)
{
	ArrayType *targets = PG_GETARG_ARRAYTYPE_P(0);
	HeapTupleHeader header = PG_GETARG_HEAPTUPLEHEADER(1);
	bool matched = false;
	PGrnCondition condition = {0};

	if (ARR_NDIM(targets) == 0)
		PG_RETURN_BOOL(false);

	condition.isTargets = &(buffers->isTargets);
	GRN_BULK_REWIND(condition.isTargets);
	PGrnConditionDeconstruct(&condition, header);
	if (!condition.query)
	{
		const char *tag = "[regexp][text-array-condition]";
		PGrnCheckRC(GRN_INVALID_ARGUMENT, "%s query must not NULL", tag);
		PG_RETURN_BOOL(false);
	}
	if (PGrnPGTextIsEmpty(condition.query))
		PG_RETURN_BOOL(false);

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_match_regexp_text_array_raw(targets, &condition);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_match_regexp_text_array_raw(targets, &condition);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_regexp_varchar(target varchar, pattern varchar) : bool
 */
Datum
pgroonga_regexp_varchar(PG_FUNCTION_ARGS)
{
	VarChar *target = PG_GETARG_VARCHAR_PP(0);
	VarChar *pattern = PG_GETARG_VARCHAR_PP(1);
	PGrnCondition condition = {0};
	bool matched = false;

	if (PGrnPGTextIsEmpty(pattern))
		PG_RETURN_BOOL(false);

	condition.query = pattern;
	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_match_regexp_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_match_regexp_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_regexp_in_text(target text, patterns text[]) : bool
 */
Datum
pgroonga_regexp_in_text(PG_FUNCTION_ARGS)
{
	text *target = PG_GETARG_TEXT_PP(0);
	Datum patterns = PG_GETARG_DATUM(1);
	PGrnCondition condition = {0};
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_execute_binary_operator_in_string(
			VARDATA_ANY(target),
			VARSIZE_ANY_EXHDR(target),
			patterns,
			&condition,
			pgroonga_match_regexp_raw);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_execute_binary_operator_in_string(
			VARDATA_ANY(target),
			VARSIZE_ANY_EXHDR(target),
			patterns,
			&condition,
			pgroonga_match_regexp_raw);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

/**
 * pgroonga_regexp_in_varchar(target varchar, patterns varchar[]) : bool
 */
Datum
pgroonga_regexp_in_varchar(PG_FUNCTION_ARGS)
{
	VarChar *target = PG_GETARG_VARCHAR_PP(0);
	Datum patterns = PG_GETARG_DATUM(1);
	PGrnCondition condition = {0};
	bool matched = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		matched = pgroonga_execute_binary_operator_in_string(
			VARDATA_ANY(target),
			VARSIZE_ANY_EXHDR(target),
			patterns,
			&condition,
			pgroonga_match_regexp_raw);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		matched = pgroonga_execute_binary_operator_in_string(
			VARDATA_ANY(target),
			VARSIZE_ANY_EXHDR(target),
			patterns,
			&condition,
			pgroonga_match_regexp_raw);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(matched);
}

static bool
pgroonga_equal_text_raw(const char *target,
						unsigned int targetSize,
						PGrnCondition *condition)
{
	if (PGrnPGTextIsEmpty(condition->query))
		return false;

	if (!PGrnPGTextIsEmpty(condition->indexName) &&
		PGrnIsTemporaryIndexSearchAvailable)
	{
		PGrnSequentialSearchSetTargetText(target, targetSize);
		PGrnSequentialSearchSetEqualText(condition);
		return PGrnSequentialSearchExecute();
	}
	else
	{
		grn_bool equal;
		grn_obj targetBuffer;
		grn_obj otherBuffer;

		GRN_TEXT_INIT(&targetBuffer, GRN_OBJ_DO_SHALLOW_COPY);
		GRN_TEXT_SET(ctx, &targetBuffer, target, targetSize);

		GRN_TEXT_INIT(&otherBuffer, GRN_OBJ_DO_SHALLOW_COPY);
		GRN_TEXT_SET(ctx,
					 &otherBuffer,
					 VARDATA_ANY(condition->query),
					 VARSIZE_ANY_EXHDR(condition->query));

		equal = grn_operator_exec_equal(ctx, &targetBuffer, &otherBuffer);

		GRN_OBJ_FIN(ctx, &targetBuffer);
		GRN_OBJ_FIN(ctx, &otherBuffer);

		return equal;
	}
}

/**
 * pgroonga_equal_text(target text, other text) : bool
 */
Datum
pgroonga_equal_text(PG_FUNCTION_ARGS)
{
	text *target = PG_GETARG_TEXT_PP(0);
	text *other = PG_GETARG_TEXT_PP(1);
	PGrnCondition condition = {0};
	bool equal = false;

	condition.query = other;
	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		equal = pgroonga_equal_text_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		equal = pgroonga_equal_text_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(equal);
}

static bool
pgroonga_equal_condition_raw(const char *target,
							 unsigned int targetSize,
							 HeapTupleHeader header)
{
	PGrnCondition condition = {0};

	condition.isTargets = &(buffers->isTargets);
	GRN_BULK_REWIND(condition.isTargets);
	PGrnConditionDeconstruct(&condition, header);
	if (!condition.query)
		return false;

	if (GRN_BULK_VSIZE(condition.isTargets) > 0 &&
		!GRN_BOOL_VALUE_AT(condition.isTargets, 0))
		return false;

	return pgroonga_equal_text_raw(target, targetSize, &condition);
}

/**
 * pgroonga_equal_text_condition(target text,
 *                               condition pgroonga_match_condition) : bool
 */
Datum
pgroonga_equal_text_condition(PG_FUNCTION_ARGS)
{
	text *target = PG_GETARG_TEXT_PP(0);
	HeapTupleHeader header = PG_GETARG_HEAPTUPLEHEADER(1);
	bool equal = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		equal = pgroonga_equal_condition_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), header);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		equal = pgroonga_equal_condition_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), header);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(equal);
}

/**
 * pgroonga_equal_varchar(target varchar, other varchar) : bool
 */
Datum
pgroonga_equal_varchar(PG_FUNCTION_ARGS)
{
	VarChar *target = PG_GETARG_VARCHAR_PP(0);
	VarChar *other = PG_GETARG_VARCHAR_PP(1);
	PGrnCondition condition = {0};
	bool equal = false;

	condition.query = other;
	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		equal = pgroonga_equal_text_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		equal = pgroonga_equal_text_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), &condition);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(equal);
}

/**
 * pgroonga_equal_varchar_condition(target text,
 *                                  condition pgroonga_match_condition) : bool
 */
Datum
pgroonga_equal_varchar_condition(PG_FUNCTION_ARGS)
{
	VarChar *target = PG_GETARG_VARCHAR_PP(0);
	HeapTupleHeader header = PG_GETARG_HEAPTUPLEHEADER(1);
	bool equal = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		equal = pgroonga_equal_condition_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), header);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		equal = pgroonga_equal_condition_raw(
			VARDATA_ANY(target), VARSIZE_ANY_EXHDR(target), header);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(equal);
}

static bool
pgroonga_equal_query_text_array_raw(ArrayType *targets,
									PGrnCondition *condition)
{
	if (ARR_NDIM(targets) == 0)
		return false;

	PGrnSequentialSearchSetTargetTexts(targets, condition);
	PGrnSequentialSearchSetQuery(condition, PGRN_SEQUENTIAL_SEARCH_EQUAL_QUERY);
	return PGrnSequentialSearchExecute();
}

/**
 * pgroonga_equal_query_text_array(targets text[], query text) : bool
 */
Datum
pgroonga_equal_query_text_array(PG_FUNCTION_ARGS)
{
	ArrayType *targets = PG_GETARG_ARRAYTYPE_P(0);
	text *query = PG_GETARG_TEXT_PP(1);
	PGrnCondition condition = {0};
	bool equal = false;

	condition.query = query;
	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		equal = pgroonga_equal_query_text_array_raw(targets, &condition);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		equal = pgroonga_equal_query_text_array_raw(targets, &condition);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(equal);
}

static bool
pgroonga_equal_query_text_array_condition_raw(ArrayType *targets,
											  HeapTupleHeader header)
{
	PGrnCondition condition = {0};

	if (ARR_NDIM(targets) == 0)
		return false;

	condition.isTargets = &(buffers->isTargets);
	GRN_BULK_REWIND(condition.isTargets);
	PGrnConditionDeconstruct(&condition, header);
	if (!condition.query)
		return false;

	return pgroonga_equal_query_text_array_raw(targets, &condition);
}

/**
 * pgroonga_equal_query_text_array_condition(
 *   targets text[],
 *   condition pgroonga_full_text_search_condition
 * ) : bool
 */
Datum
pgroonga_equal_query_text_array_condition(PG_FUNCTION_ARGS)
{
	ArrayType *targets = PG_GETARG_ARRAYTYPE_P(0);
	HeapTupleHeader header = PG_GETARG_HEAPTUPLEHEADER(1);
	bool equal = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		equal = pgroonga_equal_query_text_array_condition_raw(targets, header);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		equal = pgroonga_equal_query_text_array_condition_raw(targets, header);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(equal);
}

/**
 * pgroonga_equal_query_varchar_array(targets varchar[], query text) : bool
 */
Datum
pgroonga_equal_query_varchar_array(PG_FUNCTION_ARGS)
{
	ArrayType *targets = PG_GETARG_ARRAYTYPE_P(0);
	text *query = PG_GETARG_TEXT_PP(1);
	PGrnCondition condition = {0};
	bool equal = false;

	condition.query = query;
	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		equal = pgroonga_equal_query_text_array_raw(targets, &condition);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		equal = pgroonga_equal_query_text_array_raw(targets, &condition);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(equal);
}

/**
 * pgroonga_equal_query_varchar_array_condition(
 *   targets varchar[],
 *   condition pgroonga_full_text_search_condition
 * ) : bool
 */
Datum
pgroonga_equal_query_varchar_array_condition(PG_FUNCTION_ARGS)
{
	ArrayType *targets = PG_GETARG_ARRAYTYPE_P(0);
	HeapTupleHeader header = PG_GETARG_HEAPTUPLEHEADER(1);
	bool equal = false;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabledSeqScan(fcinfo));
	{
		equal = pgroonga_equal_query_text_array_condition_raw(targets, header);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		equal = pgroonga_equal_query_text_array_condition_raw(targets, header);
	}
	PGRN_RLS_ENABLED_END();

	PG_RETURN_BOOL(equal);
}

static bool
PGrnNeedMaxRecordSizeUpdate(Relation index)
{
	TupleDesc desc = RelationGetDescr(index);
	unsigned int nVarCharColumns = 0;
	unsigned int i;

	for (i = 0; i < desc->natts; i++)
	{
		Form_pg_attribute attribute;

		attribute = TupleDescAttr(desc, i);
		switch (attribute->atttypid)
		{
		case VARCHAROID:
			nVarCharColumns++;
			break;
		case TEXTOID:
		case VARCHARARRAYOID:
		case TEXTARRAYOID:
			return true;
			break;
		default:
			break;
		}
	}

	return nVarCharColumns >= 2;
}

#define PGRN_INDEX_ONLY_SCAN_THRESHOLD_SIZE (INDEX_SIZE_MASK * 0.9)

static void
PGrnUpdateMaxRecordSize(Relation index, uint32_t recordSize)
{
	uint32_t currentMaxRecordSize;

	if (recordSize < PGRN_INDEX_ONLY_SCAN_THRESHOLD_SIZE)
		return;

	currentMaxRecordSize = PGrnIndexStatusGetMaxRecordSize(index);
	if (recordSize < currentMaxRecordSize)
		return;

	PGrnIndexStatusSetMaxRecordSize(index, recordSize);
}

static uint32_t
PGrnComputeSize(grn_obj *buffer)
{
	switch (buffer->header.type)
	{
	case GRN_BULK:
		return GRN_BULK_VSIZE(buffer);
	case GRN_UVECTOR:
	{
		const unsigned int element_size = grn_uvector_element_size(ctx, buffer);
		const unsigned int n_elements = grn_uvector_size(ctx, buffer);
		return element_size * n_elements;
	}
	case GRN_VECTOR:
	{
		uint32_t size = 0;
		unsigned int i;
		const unsigned int n = grn_vector_size(ctx, buffer);
		for (i = 0; i < n; i++)
		{
			const char *value;
			size += grn_vector_get_element(ctx, buffer, i, &value, NULL, NULL);
		}
		return size;
	}
	default:
		return 0;
	}
}

static uint32_t
PGrnInsertColumn(Relation index,
				 grn_obj *sourcesTable,
				 Datum *values,
				 PGrnWALData *walData,
				 unsigned int i,
				 grn_id id,
				 const char *tag)
{
	TupleDesc desc = RelationGetDescr(index);
	Form_pg_attribute attribute = TupleDescAttr(desc, i);
	NameData *name = &(attribute->attname);
	grn_obj *dataColumn = PGrnLookupColumn(sourcesTable, name->data, ERROR);
	grn_obj *rawValue = &(buffers->general);
	grn_obj *value;
	grn_id rawDomain;
	unsigned char flags;
	grn_id domain;

	rawDomain = PGrnGetType(index, i, &flags);
	grn_obj_reinit(ctx, rawValue, rawDomain, flags);
	PGrnConvertFromData(values[i], attribute->atttypid, rawValue);
	domain = grn_obj_get_range(ctx, dataColumn);
	if (domain == rawDomain)
	{
		value = rawValue;
	}
	else
	{
		grn_rc rc = GRN_SUCCESS;
		grn_obj rawElement;
		grn_obj *element = &(buffers->castElement);
		GRN_VOID_INIT(&rawElement);
		value = &(buffers->cast);
		grn_obj_reinit(ctx, value, domain, flags);
		if (grn_obj_is_vector(ctx, rawValue))
		{
			uint32_t n = grn_vector_size(ctx, rawValue);
			uint32_t j;
			for (j = 0; j < n; j++)
			{
				const char *elementValue;
				float weight;
				grn_id elementDomain;
				uint32_t elementSize = grn_vector_get_element_float(
					ctx, rawValue, j, &elementValue, &weight, &elementDomain);
				GRN_OBJ_FIN(ctx, &rawElement);
				GRN_VALUE_VAR_SIZE_INIT(
					&rawElement, GRN_OBJ_DO_SHALLOW_COPY, elementDomain);
				GRN_TEXT_SET(ctx, &rawElement, elementValue, elementSize);
				grn_obj_reinit(ctx, element, domain, 0);
				rc = grn_obj_cast(ctx, &rawElement, element, true);
				if (rc != GRN_SUCCESS)
					break;
				grn_vector_add_element_float(ctx,
											 value,
											 GRN_BULK_HEAD(element),
											 GRN_BULK_VSIZE(element),
											 weight,
											 domain);
			}
		}
		else if (grn_obj_is_uvector(ctx, value))
		{
			uint32_t elementSize = grn_uvector_element_size(ctx, rawValue);
			uint32_t n = grn_uvector_size(ctx, rawValue);
			uint32_t j;
			GRN_OBJ_FIN(ctx, &rawElement);
			GRN_VALUE_FIX_SIZE_INIT(
				&rawElement, GRN_OBJ_DO_SHALLOW_COPY, rawDomain);
			grn_obj_reinit(ctx, element, domain, 0);
			for (j = 0; j < n; j++)
			{
				GRN_TEXT_SET(ctx,
							 &rawElement,
							 GRN_BULK_HEAD(rawValue) + (elementSize * j),
							 elementSize);
				GRN_BULK_REWIND(element);
				rc = grn_obj_cast(ctx, &rawElement, element, true);
				if (rc != GRN_SUCCESS)
					break;
				grn_bulk_write(ctx,
							   value,
							   GRN_BULK_HEAD(element),
							   GRN_BULK_VSIZE(element));
			}
		}
		else
		{
			rc = grn_obj_cast(ctx, rawValue, value, true);
		}
		GRN_OBJ_FIN(ctx, &rawElement);

		if (rc != GRN_SUCCESS)
		{
			elog(WARNING,
				 "pgroonga: %s <%s.%s>: failed to cast: <%s>",
				 tag,
				 index->rd_rel->relname.data,
				 name->data,
				 PGrnInspect(rawValue));
			return 0;
		}
	}

	grn_obj_set_value(ctx, dataColumn, id, value, GRN_OBJ_SET);
	PGrnCheck("%s failed to set column value", tag);

	PGrnWALInsertColumn(walData, dataColumn, rawValue);

	return PGrnComputeSize(value);
}

static bool
PGrnIsJSONBIndex(Relation index)
{
	TupleDesc desc = RelationGetDescr(index);
	return desc->natts == 1 &&
		   PGrnAttributeIsJSONB(TupleDescAttr(desc, 0)->atttypid);
}

static uint32_t
PGrnInsert(Relation index,
		   grn_obj *sourcesTable,
		   grn_obj *sourcesCtidColumn,
		   Datum *values,
		   bool *isnull,
		   ItemPointer ht_ctid,
		   bool isBulkInsert,
		   PGrnWALData *walData)
{
	const char *tag = "[insert]";
	TupleDesc desc = RelationGetDescr(index);
	grn_id id;
	uint64_t packedCtid = PGrnCtidPack(ht_ctid);
	unsigned int i;
	uint32_t recordSize = 0;

	if (PGrnIsJSONBIndex(index))
	{
		return PGrnJSONBInsert(index,
							   sourcesTable,
							   sourcesCtidColumn,
							   values,
							   isnull,
							   PGrnCtidPack(ht_ctid));
	}

	if (!isBulkInsert)
		walData = PGrnWALStart(index);
	{
		size_t nValidAttributes = 1; /* ctid is always valid. */

		for (i = 0; i < desc->natts; i++)
		{
			if (!isnull[i])
				nValidAttributes++;
		}
		PGrnWALInsertStart(walData, sourcesTable, nValidAttributes);
	}

	PG_TRY();
	{
		if (sourcesTable->header.type == GRN_TABLE_NO_KEY)
		{
			id = grn_table_add(ctx, sourcesTable, NULL, 0, NULL);
			PGrnCheck("%s failed to add a record", tag);
			if (id == GRN_ID_NIL)
			{
				PGrnCheckRC(
					GRN_UNKNOWN_ERROR, "%s failed to add a record", tag);
			}
			GRN_UINT64_SET(ctx, &(buffers->ctid), packedCtid);
			grn_obj_set_value(
				ctx, sourcesCtidColumn, id, &(buffers->ctid), GRN_OBJ_SET);
			PGrnCheck("%s failed to set ctid value: <%u>: <%" PRIu64 ">",
					  tag,
					  id,
					  packedCtid);
			GRN_LOG(ctx,
					GRN_LOG_DEBUG,
					"pgroonga: "
					"%s[array] <%s>(%u): <%u>: <(%u,%u),%u>(%" PRIu64 ")",
					tag,
					index->rd_rel->relname.data,
					index->rd_id,
					id,
					ht_ctid->ip_blkid.bi_hi,
					ht_ctid->ip_blkid.bi_lo,
					ht_ctid->ip_posid,
					packedCtid);
			PGrnWALInsertColumn(walData, sourcesCtidColumn, &(buffers->ctid));
		}
		else
		{
			id = grn_table_add(
				ctx, sourcesTable, &packedCtid, sizeof(uint64_t), NULL);
			PGrnCheck(
				"%s failed to add a record: <%" PRIu64 ">", tag, packedCtid);
			if (id == GRN_ID_NIL)
			{
				PGrnCheckRC(GRN_UNKNOWN_ERROR,
							"%s failed to add a record: <%" PRIu64 ">",
							tag,
							packedCtid);
			}
			PGrnWALInsertKeyRaw(walData, &packedCtid, sizeof(uint64_t));
			GRN_LOG(ctx,
					GRN_LOG_DEBUG,
					"pgroonga: %s <%s>(%u): <%u>: <(%u,%u),%u>(%" PRIu64 ")",
					tag,
					index->rd_rel->relname.data,
					index->rd_id,
					id,
					ht_ctid->ip_blkid.bi_hi,
					ht_ctid->ip_blkid.bi_lo,
					ht_ctid->ip_posid,
					packedCtid);
		}

		for (i = 0; i < desc->natts; i++)
		{
			if (isnull[i])
				continue;
			recordSize += PGrnInsertColumn(
				index, sourcesTable, values, walData, i, id, tag);
		}

		PGrnWALInsertFinish(walData);
		if (!isBulkInsert)
			PGrnWALFinish(walData);
	}
	PG_CATCH();
	{
		if (!isBulkInsert)
			PGrnWALAbort(walData);
		PG_RE_THROW();
	}
	PG_END_TRY();

	return recordSize;
}

static bool
pgroonga_insert(Relation index,
				Datum *values,
				bool *isnull,
				ItemPointer ctid,
				Relation heap,
				IndexUniqueCheck checkUnique,
				bool indexUnchanged,
				struct IndexInfo *indexInfo)
{
	const char *tag = "[insert]";
	grn_obj *sourcesTable;
	grn_obj *sourcesCtidColumn = NULL;
	uint32_t recordSize;

	PGRN_TRACE_LOG_ENTER();

	if (!PGrnIsWritable())
	{
		ereport(ERROR,
				(errcode(ERRCODE_E_R_E_MODIFYING_SQL_DATA_NOT_PERMITTED),
				 errmsg("pgroonga: %s "
						"can't insert a record "
						"while pgroonga.writable is false",
						tag)));
	}

	/*
	 * pgroonga_insert() may be called between pgroonga_beginscan() and
	 * pgroonga_endscan() while executing an UPDATE statement with a WHERE
	 * clause.
	 * If an UPDATE statement with a WHERE clause and VACUUM are executed
	 * concurrently, EnsureLatestDB() may be called in this scope, as shown
	 * below:
	 *
	 * pgroonga: [trace][pgroonga_beginscan][enter]
	 * pgroonga: [trace][pgroonga_beginscan][exit]
	 * pgroonga: [trace][pgroonga_rescan][enter]
	 * pgroonga: [trace][pgroonga_rescan][exit]
	 * pgroonga: [trace][pgroonga_insert][enter]
	 * pgroonga: [trace][PGrnEnsureLatestDB][enter]
	 * pgroonga: [trace][PGrnUnmapDB][enter]
	 * pgroonga: [trace][PGrnUnmapDB][exit]
	 * pgroonga: [trace][PGrnEnsureLatestDB][exit]
	 * pgroonga: [trace][pgroonga_insert][exit]
	 * pgroonga: [trace][pgroonga_endscan][enter]
	 * pgroonga: [trace][pgroonga_endscan][exit]
	 *
	 * EnsureLatestDB() should not be called in this scope.
	 * See the comment for PGrnEnsureLatestDB() for detail.
	 * Therefore, prevent EnsureLatestDB() from being called while between
	 * pgroonga_beginscan() and pgroonga_endscan. */
	if (PGrnNScanOpaques == 0)
	{
		PGrnEnsureLatestDB();
	}

	PGrnWALApply(index);

	sourcesTable = PGrnLookupSourcesTable(index, ERROR);
	if (sourcesTable->header.type == GRN_TABLE_NO_KEY)
	{
		sourcesCtidColumn = PGrnLookupSourcesCtidColumn(index, ERROR);
	}
	recordSize = PGrnInsert(index,
							sourcesTable,
							sourcesCtidColumn,
							values,
							isnull,
							ctid,
							false,
							NULL);
	if (PGrnNeedMaxRecordSizeUpdate(index))
		PGrnUpdateMaxRecordSize(index, recordSize);
	grn_db_touch(ctx, grn_ctx_db(ctx));

	PGRN_TRACE_LOG_EXIT();

	return false;
}

static void
PGrnPrimaryKeyColumnsFin(slist_head *columns)
{
	while (!slist_is_empty(columns))
	{
		slist_node *current;
		PGrnPrimaryKeyColumn *column;

		current = slist_pop_head_node(columns);
		column = slist_container(PGrnPrimaryKeyColumn, node, current);
		free(column);
	}
}

static void
PGrnPrimaryKeyColumnsInit(slist_head *columns, PGrnScanOpaque so)
{
	Relation table;
	List *indexOIDList;
	ListCell *cell;

	table = RelationIdGetRelation(so->dataTableID);
	indexOIDList = RelationGetIndexList(table);
	foreach (cell, indexOIDList)
	{
		const LOCKMODE lockMode = AccessShareLock;
		Oid indexOID = lfirst_oid(cell);
		Relation primaryKeyIndex;
		int i;

		primaryKeyIndex = index_open(indexOID, lockMode);
		if (!primaryKeyIndex->rd_index->indisprimary)
		{
			index_close(primaryKeyIndex, lockMode);
			continue;
		}

		for (i = 0; i < primaryKeyIndex->rd_index->indnatts; i++)
		{
			Oid primaryKeyNumber;
			int j;
			bool havePrimaryKey = false;

			primaryKeyNumber = primaryKeyIndex->rd_index->indkey.values[i];

			for (j = 0; j < so->index->rd_index->indnatts; j++)
			{
				TupleDesc desc;
				const char *columnName;
				PGrnPrimaryKeyColumn *primaryKeyColumn;

				if (so->index->rd_index->indkey.values[j] != primaryKeyNumber)
					continue;

				primaryKeyColumn = (PGrnPrimaryKeyColumn *) malloc(
					sizeof(PGrnPrimaryKeyColumn));

				desc = RelationGetDescr(table);
				columnName = TupleDescAttr(so->index->rd_att, j)->attname.data;

				primaryKeyColumn->number = primaryKeyNumber;
				primaryKeyColumn->type =
					TupleDescAttr(desc, primaryKeyNumber - 1)->atttypid;
				primaryKeyColumn->domain =
					PGrnGetType(primaryKeyIndex, i, &(primaryKeyColumn->flags));
				primaryKeyColumn->column = grn_obj_column(
					ctx, so->sourcesTable, columnName, strlen(columnName));
				slist_push_head(columns, &(primaryKeyColumn->node));
				havePrimaryKey = true;
				break;
			}

			if (!havePrimaryKey)
			{
				PGrnPrimaryKeyColumnsFin(columns);
				break;
			}
		}

		index_close(primaryKeyIndex, lockMode);
		break;
	}
	list_free(indexOIDList);
	RelationClose(table);
}

static void
PGrnScanOpaqueInitPrimaryKeyColumns(PGrnScanOpaque so)
{
	slist_init(&(so->primaryKeyColumns));
	PGrnPrimaryKeyColumnsInit(&(so->primaryKeyColumns), so);
}

static void
PGrnScanOpaqueInitSources(PGrnScanOpaque so)
{
	so->sourcesTable = PGrnLookupSourcesTable(so->index, ERROR);
	if (so->sourcesTable->header.type == GRN_TABLE_NO_KEY)
	{
		so->sourcesCtidColumn = PGrnLookupSourcesCtidColumn(so->index, ERROR);
	}
	else
	{
		so->sourcesCtidColumn = NULL;
	}
}

static void
PGrnScanOpaqueInit(PGrnScanOpaque so, Relation index)
{
	GRN_LOG(ctx,
			GRN_LOG_DEBUG,
			"pgroonga: [initialize][scan-opaque][start] %u",
			PGrnNScanOpaques);

	so->index = index;

	so->memoryContext =
		AllocSetContextCreate(CurrentMemoryContext,
							  "PGroonga scan opaque temporay context",
							  ALLOCSET_DEFAULT_SIZES);

	so->dataTableID = index->rd_index->indrelid;
	PGrnScanOpaqueInitSources(so);
	so->ctidResolveTable = NULL;
	GRN_VOID_INIT(&(so->minBorderValue));
	GRN_VOID_INIT(&(so->maxBorderValue));
	so->searched = NULL;
	so->sorted = NULL;
	so->targetTable = NULL;
	so->indexCursor = NULL;
	so->tableCursor = NULL;
	so->ctidAccessor = NULL;
	so->scoreAccessor = NULL;
	so->currentID = GRN_ID_NIL;

	GRN_BOOL_INIT(&(so->canReturns), GRN_OBJ_VECTOR);

	dlist_push_head(&PGrnScanOpaques, &(so->node));
	PGrnNScanOpaques++;
	PGrnScanOpaqueInitPrimaryKeyColumns(so);
	so->scoreTargetRecords = NULL;

	GRN_LOG(ctx,
			GRN_LOG_DEBUG,
			"pgroonga: [initialize][scan-opaque][end] %u: <%p>",
			PGrnNScanOpaques,
			so);
}

static void
PGrnScanOpaqueReinit(PGrnScanOpaque so)
{
	GRN_LOG(ctx,
			GRN_LOG_DEBUG,
			"pgroonga: [reinitialize][scan-opaque][start] %u: <%p>",
			PGrnNScanOpaques,
			so);

	so->currentID = GRN_ID_NIL;
	if (so->scoreAccessor)
	{
		grn_obj_unlink(ctx, so->scoreAccessor);
		so->scoreAccessor = NULL;
	}
	if (so->ctidAccessor)
	{
		grn_obj_unlink(ctx, so->ctidAccessor);
		so->ctidAccessor = NULL;
	}
	if (so->indexCursor)
	{
		grn_obj_close(ctx, so->indexCursor);
		so->indexCursor = NULL;
	}
	if (so->tableCursor)
	{
		grn_table_cursor_close(ctx, so->tableCursor);
		so->tableCursor = NULL;
	}
	GRN_BULK_REWIND(&(so->minBorderValue));
	GRN_BULK_REWIND(&(so->maxBorderValue));
	if (so->ctidResolveTable)
	{
		grn_obj_close(ctx, so->ctidResolveTable);
		so->ctidResolveTable = NULL;
	}
	if (so->sorted)
	{
		grn_obj_close(ctx, so->sorted);
		so->sorted = NULL;
	}
	if (so->searched)
	{
		grn_obj_close(ctx, so->searched);
		so->searched = NULL;
	}
	GRN_BULK_REWIND(&(so->canReturns));

	GRN_LOG(ctx,
			GRN_LOG_DEBUG,
			"pgroonga: [reinitialize][scan-opaque][end] %u: <%p>",
			PGrnNScanOpaques,
			so);
}

static void
PGrnScanOpaqueFin(PGrnScanOpaque so)
{
	GRN_LOG(ctx,
			GRN_LOG_DEBUG,
			"pgroonga: [finalize][scan-opaque][start] %u: <%p>",
			PGrnNScanOpaques,
			so);

	dlist_delete(&(so->node));
	PGrnNScanOpaques--;

	PGrnPrimaryKeyColumnsFin(&(so->primaryKeyColumns));
	if (so->scoreTargetRecords)
	{
		grn_obj_close(ctx, so->scoreTargetRecords);
		so->scoreTargetRecords = NULL;
	}

	PGrnScanOpaqueReinit(so);

	GRN_OBJ_FIN(ctx, &(so->minBorderValue));
	GRN_OBJ_FIN(ctx, &(so->maxBorderValue));

	GRN_OBJ_FIN(ctx, &(so->canReturns));

	GRN_LOG(ctx,
			GRN_LOG_DEBUG,
			"pgroonga: [finalize][scan-opaque][end] %u: <%p>",
			PGrnNScanOpaques,
			so);

	free(so);
}

static IndexScanDesc
pgroonga_beginscan(Relation index, int nKeys, int nOrderBys)
{
	IndexScanDesc scan;
	PGrnScanOpaque so;

	PGRN_TRACE_LOG_ENTER();

	/* We should not call PGrnEnsureLatestDB() here. See the
	 * PGrnEnsureLatestDB() comment for details. */
	/* PGrnEnsureLatestDB(); */

	scan = RelationGetIndexScan(index, nKeys, nOrderBys);

	so = (PGrnScanOpaque) malloc(sizeof(PGrnScanOpaqueData));
	PGrnScanOpaqueInit(so, index);

	GRN_LOG(ctx, GRN_LOG_DEBUG, "pgroonga: [scan][begin] <%p>", so);

	scan->opaque = so;

	PGRN_TRACE_LOG_EXIT();

	return scan;
}

static bool
PGrnSearchIsInCondition(ScanKey key)
{
	return ((key->sk_flags & SK_SEARCHARRAY) &&
			((key->sk_strategy == PGrnEqualStrategyNumber) ||
			 (key->sk_strategy == PGrnEqualStrategyV2Number)));
}

static bool
PGrnSearchIsMatchInCondition(ScanKey key)
{
	return (key->sk_flags & SK_SEARCHARRAY) &&
		   ((key->sk_strategy == PGrnMatchStrategyNumber) ||
			(key->sk_strategy == PGrnMatchStrategyV2Number));
}

static bool
PGrnSearchIsLikeAnyCondition(ScanKey key)
{
	return (key->sk_flags & SK_SEARCHARRAY) &&
		   (key->sk_strategy == PGrnLikeStrategyNumber);
}

static bool
PGrnSearchIsILikeAnyCondition(ScanKey key)
{
	return (key->sk_flags & SK_SEARCHARRAY) &&
		   (key->sk_strategy == PGrnILikeStrategyNumber);
}

static void PGrnSearchBuildConditionLikeMatch(PGrnSearchData *data,
											  grn_obj *targetColumn,
											  grn_obj *query);

static void
PGrnSearchBuildConditionIn(PGrnSearchData *data,
						   ScanKey key,
						   grn_obj *targetColumn,
						   Form_pg_attribute attribute,
						   grn_operator operator)
{
	const char *tag = "[build-condition][in]";
	const char *tag_any = "[build-condition][any]";
	ArrayType *values;
	int n_dimensions;
	grn_id domain;
	unsigned char flags = 0;
	int i, n;
	int nArgs = 0;

	values = DatumGetArrayTypeP(key->sk_argument);
	n_dimensions = ARR_NDIM(values);
	switch (n_dimensions)
	{
	case 0:
		grn_obj_reinit(ctx, &(buffers->general), GRN_DB_BOOL, 0);
		GRN_BOOL_SET(ctx, &(buffers->general), GRN_FALSE);
		PGrnExprAppendConst(
			data->expression, &(buffers->general), GRN_OP_PUSH, 1, tag_any);
		return;
	case 1:
		/* OK */
		break;
	default:
		PGrnCheckRC(GRN_FUNCTION_NOT_IMPLEMENTED,
					"%s 2 or more dimensions array isn't supported yet: %d",
					tag,
					n_dimensions);
		return;
	}

	domain = PGrnPGTypeToGrnType(attribute->atttypid, &flags);
	grn_obj_reinit(ctx, &(buffers->general), domain, flags);
	n = ARR_DIMS(values)[0];

	if (operator== GRN_OP_EQUAL)
	{
		PGrnExprAppendObject(data->expression,
							 PGrnLookup("in_values", ERROR),
							 GRN_OP_PUSH,
							 1,
							 tag,
							 NULL);
		PGrnExprAppendObject(
			data->expression, targetColumn, GRN_OP_GET_VALUE, 1, tag, NULL);
		nArgs++;
	}

	for (i = 1; i <= n; i++)
	{
		Datum valueDatum;
		bool isNULL;

		valueDatum = array_ref(values,
							   1,
							   &i,
							   -1,
							   attribute->attlen,
							   attribute->attbyval,
							   attribute->attalign,
							   &isNULL);
		if (isNULL)
			continue;

		PGrnConvertFromData(
			valueDatum, attribute->atttypid, &(buffers->general));

		if (operator== GRN_OP_EQUAL)
		{
			PGrnExprAppendConst(
				data->expression, &(buffers->general), GRN_OP_PUSH, 1, tag);
		}
		else
		{
			switch (key->sk_strategy)
			{
			case PGrnLikeStrategyNumber:
			case PGrnILikeStrategyNumber:
				PGrnSearchBuildConditionLikeMatch(
					data, targetColumn, &(buffers->general));
				break;
			default:
				PGrnSearchBuildConditionBinaryOperation(
					data, targetColumn, &(buffers->general), operator);
				break;
			}
			if (nArgs > 0)
				PGrnExprAppendOp(data->expression, GRN_OP_OR, 2, tag, NULL);
		}
		nArgs++;
	}

	if (operator== GRN_OP_EQUAL)
		PGrnExprAppendOp(data->expression, GRN_OP_CALL, nArgs, tag, NULL);
}

static void
PGrnSearchBuildConditionPrepareConditionBuildMatchColumns(
	PGrnSearchData *data,
	grn_obj *matchColumns,
	grn_index_datum *indexData,
	ArrayType *weights,
	ArrayType *scorers,
	const char *tag)
{
	char indexName[GRN_TABLE_MAX_KEY_SIZE];
	ArrayIterator weightsIterator = NULL;
	ArrayIterator scorersIterator = NULL;
	int section;
	int nMatchColumns = 0;
	grn_obj *substitutedScorer = &(buffers->general);

	{
		int nameSize;
		nameSize = grn_obj_name(
			ctx, indexData->index, indexName, GRN_TABLE_MAX_KEY_SIZE);
		indexName[nameSize] = '\0';
	}

	if (weights)
		weightsIterator = array_create_iterator(weights, 0, NULL);
	if (scorers)
		scorersIterator = array_create_iterator(scorers, 0, NULL);

	section = -1;
	grn_obj_reinit(ctx, substitutedScorer, GRN_DB_TEXT, 0);
	while (true)
	{
		Datum weightDatum;
		bool weightIsNULL = true;
		Datum scorerDatum;
		bool scorerIsNULL = true;
		int32 weight = 1;
		text *scorer = NULL;

		section++;

		if (weightsIterator)
		{
			if (!array_iterate(weightsIterator, &weightDatum, &weightIsNULL))
			{
				array_free_iterator(weightsIterator);
				weightsIterator = NULL;
			}
		}
		if (scorersIterator)
		{
			if (!array_iterate(scorersIterator, &scorerDatum, &scorerIsNULL))
			{
				array_free_iterator(scorersIterator);
				scorersIterator = NULL;
			}
		}

		if (!weightsIterator && !scorersIterator)
			break;

		if (!weightIsNULL)
			weight = DatumGetInt32(weightDatum);
		if (!scorerIsNULL)
			scorer = DatumGetTextPP(scorerDatum);

		if (weight == 0)
			continue;

		if (scorer)
		{
			GRN_BULK_REWIND(substitutedScorer);
			PGrnStringSubstituteIndex(VARDATA_ANY(scorer),
									  VARSIZE_ANY_EXHDR(scorer),
									  substitutedScorer,
									  indexName,
									  section);
			grn_expr_parse(ctx,
						   matchColumns,
						   GRN_TEXT_VALUE(substitutedScorer),
						   GRN_TEXT_LEN(substitutedScorer),
						   NULL,
						   GRN_OP_MATCH,
						   GRN_OP_AND,
						   GRN_EXPR_SYNTAX_SCRIPT);
			PGrnCheck("%s failed to parse scorer: <%s>[%d]: <%.*s>",
					  tag,
					  indexName,
					  section,
					  (int) VARSIZE_ANY_EXHDR(scorer),
					  VARDATA_ANY(scorer));
		}
		else
		{
			PGrnExprAppendObject(matchColumns,
								 indexData->index,
								 GRN_OP_PUSH,
								 1,
								 tag,
								 "section: <%d>",
								 section);
			PGrnExprAppendConstInteger(matchColumns,
									   section,
									   GRN_OP_PUSH,
									   1,
									   tag,
									   "index: <%s>",
									   indexName);
			PGrnExprAppendOp(matchColumns,
							 GRN_OP_GET_MEMBER,
							 2,
							 tag,
							 "<%s>[%d]",
							 indexName,
							 section);
		}
		if (weight != 1)
		{
			PGrnExprAppendConstInteger(matchColumns,
									   weight,
									   GRN_OP_PUSH,
									   1,
									   tag,
									   "index: <%s>[%d]",
									   indexName,
									   section);
			PGrnExprAppendOp(matchColumns,
							 GRN_OP_STAR,
							 2,
							 tag,
							 "<%s>[%d] * <%d>",
							 indexName,
							 section,
							 weight);
		}

		if (nMatchColumns > 0)
		{
			PGrnExprAppendOp(matchColumns,
							 GRN_OP_OR,
							 2,
							 tag,
							 "<%s>[%d]",
							 indexName,
							 section);
		}

		nMatchColumns++;
	}
	if (weightsIterator)
		array_free_iterator(weightsIterator);
	if (scorersIterator)
		array_free_iterator(scorersIterator);
}

static void
PGrnSearchBuildConditionPrepareCondition(PGrnSearchData *data,
										 ScanKey key,
										 grn_obj *targetColumn,
										 Form_pg_attribute attribute,
										 grn_operator operator,
										 PGrnCondition * condition,
										 grn_obj **matchTarget,
										 const char *tag)
{
	grn_index_datum indexData;
	unsigned int nIndexData;
	HeapTupleHeader header;

	nIndexData =
		grn_column_find_index_data(ctx, targetColumn, operator, & indexData, 1);
	if (nIndexData == 0)
	{
		PGrnCheckRC(GRN_OBJECT_CORRUPT,
					"%s index doesn't exist for target column: <%s>",
					tag,
					PGrnInspectName(targetColumn));
	}

	header = DatumGetHeapTupleHeader(key->sk_argument);
	PGrnConditionDeconstruct(condition, header);
	data->fuzzyMaxDistanceRatio = condition->fuzzyMaxDistanceRatio;
	if (!condition->query)
	{
		PGrnCheckRC(GRN_INVALID_ARGUMENT, "%s query must not NULL", tag);
	}

	if (!condition->weights && !condition->scorers)
	{
		*matchTarget = targetColumn;
		return;
	}

	if (condition->weights && ARR_NDIM(condition->weights) == 0)
	{
		PGrnCheckRC(
			GRN_INVALID_ARGUMENT, "%s weights must not empty array", tag);
	}

	{
		grn_obj *matchColumns, *matchColumnsVariable;

		GRN_EXPR_CREATE_FOR_QUERY(
			ctx, data->sourcesTable, matchColumns, matchColumnsVariable);
		GRN_PTR_PUT(ctx, &(data->matchTargets), matchColumns);

		PGrnSearchBuildConditionPrepareConditionBuildMatchColumns(
			data,
			matchColumns,
			&indexData,
			condition->weights,
			condition->scorers,
			tag);

		*matchTarget = matchColumns;
	}
}

static void
PGrnSearchBuildConditionSemanticSearch(PGrnSearchData *data,
									   ScanKey key,
									   grn_obj *targetColumn,
									   Form_pg_attribute attribute)
{
	const char *tag = "[build-condition][semantic-search-condition]";
	PGrnCondition condition = {0};
	grn_obj *matchTarget;

	if (key->sk_strategy == PGrnSimilarStrategyV2Number)
	{
		condition.query = DatumGetTextPP(key->sk_argument);
	}
	else
	{
		PGrnSearchBuildConditionPrepareCondition(data,
												 key,
												 targetColumn,
												 attribute,
												 GRN_OP_SIMILAR,
												 &condition,
												 &matchTarget,
												 tag);
	}

	if (PGrnPGTextIsEmpty(condition.query))
	{
		data->isEmptyCondition = true;
		return;
	}

	PGrnExprAppendObject(data->expression,
						 PGrnLookup("language_model_knn", ERROR),
						 GRN_OP_PUSH,
						 1,
						 tag,
						 NULL);
	PGrnExprAppendObject(
		data->expression, targetColumn, GRN_OP_GET_VALUE, 1, tag, NULL);
	PGrnExprAppendConstString(data->expression,
							  VARDATA_ANY(condition.query),
							  VARSIZE_ANY_EXHDR(condition.query),
							  GRN_OP_PUSH,
							  1,
							  tag);
	// TODO: Add support for n_probes and k.
	PGrnExprAppendOp(data->expression, GRN_OP_CALL, 2, tag, NULL);
}

static void
PGrnSearchBuildConditionBinaryOperationCondition(PGrnSearchData *data,
												 ScanKey key,
												 grn_obj *targetColumn,
												 Form_pg_attribute attribute,
												 grn_operator operator)
{
	char tag[256];
	PGrnCondition condition = {0};
	grn_obj *matchTarget;

	snprintf(tag,
			 sizeof(tag),
			 "[build-condition][%s-condition]",
			 grn_operator_to_string(operator));
	PGrnSearchBuildConditionPrepareCondition(
		data, key, targetColumn, attribute, operator, & condition, &matchTarget, tag);
	if (PGrnPGTextIsEmpty(condition.query))
	{
		if (operator== GRN_OP_REGEXP)
		{
			data->isEmptyCondition = true;
			return;
		}
		PGrnCheckRC(
			GRN_INVALID_ARGUMENT, "%s query must not an empty string", tag);
	}

	PGrnExprAppendObject(data->expression,
						 matchTarget,
						 GRN_OP_GET_VALUE,
						 1,
						 tag,
						 "target-column: %s",
						 PGrnInspect(targetColumn));
	PGrnExprAppendConstString(data->expression,
							  VARDATA_ANY(condition.query),
							  VARSIZE_ANY_EXHDR(condition.query),
							  GRN_OP_PUSH,
							  1,
							  tag);
	PGrnExprAppendOp(data->expression, operator, 2, tag, NULL);
}

static void
PGrnSearchBuildConditionQueryCondition(PGrnSearchData *data,
									   ScanKey key,
									   grn_obj *targetColumn,
									   Form_pg_attribute attribute)
{
	const char *tag = "[build-condition][query-condition]";
	PGrnCondition condition = {0};
	grn_obj *matchTarget;
	grn_operator defaultOperator;
	grn_expr_flags flags = PGRN_EXPR_QUERY_PARSE_FLAGS;

	PGrnSearchBuildConditionPrepareCondition(data,
											 key,
											 targetColumn,
											 attribute,
											 GRN_OP_MATCH,
											 &condition,
											 &matchTarget,
											 tag);
	if (PGrnStringIsEmpty(VARDATA_ANY(condition.query),
						  VARSIZE_ANY_EXHDR(condition.query)))
	{
		data->isEmptyCondition = true;
		return;
	}

	if (key->sk_strategy == PGrnEqualQueryFTSConditionStrategyV2Number ||
		key->sk_strategy == PGrnEqualQueryConditionStrategyV2Number)
	{
		defaultOperator = GRN_OP_EQUAL;
	}
	else
	{
		defaultOperator = GRN_OP_MATCH;
	}
	flags |= PGrnOptionsGetExprParseFlags(data->index);
	grn_expr_parse(ctx,
				   data->expression,
				   VARDATA_ANY(condition.query),
				   VARSIZE_ANY_EXHDR(condition.query),
				   matchTarget,
				   defaultOperator,
				   GRN_OP_AND,
				   flags);
	PGrnCheck("%s failed to parse query: <%.*s>",
			  tag,
			  (int) VARSIZE_ANY_EXHDR(condition.query),
			  VARDATA_ANY(condition.query));
}

static void
PGrnSearchBuildConditionLikeMatchFlush(grn_obj *expression,
									   grn_obj *targetColumn,
									   grn_obj *keyword,
									   int *nKeywords)
{
	const char *tag = "[build-condition][like-match-flush]";
	if (GRN_TEXT_LEN(keyword) == 0)
		return;

	PGrnExprAppendObject(
		expression, targetColumn, GRN_OP_GET_VALUE, 1, tag, NULL);

	PGrnExprAppendConstString(expression,
							  GRN_TEXT_VALUE(keyword),
							  GRN_TEXT_LEN(keyword),
							  GRN_OP_PUSH,
							  1,
							  tag);
	PGrnExprAppendOp(expression, GRN_OP_MATCH, 2, tag, NULL);
	if (*nKeywords > 0)
		PGrnExprAppendOp(expression, GRN_OP_OR, 2, tag, NULL);
	(*nKeywords)++;

	GRN_BULK_REWIND(keyword);
}

static void
PGrnSearchBuildConditionLikeMatch(PGrnSearchData *data,
								  grn_obj *targetColumn,
								  grn_obj *query)
{
	const char *tag = "[build-condition][like-match]";
	grn_obj *expression;
	const char *queryRaw;
	size_t i, querySize;
	int nKeywords = 0;

	expression = data->expression;
	queryRaw = GRN_TEXT_VALUE(query);
	querySize = GRN_TEXT_LEN(query);

	if (querySize == 0)
	{
		data->isEmptyCondition = true;
		return;
	}

	GRN_BULK_REWIND(&(buffers->keyword));
	for (i = 0; i < querySize; i++)
	{
		switch (queryRaw[i])
		{
		case '\\':
			if (i == querySize)
			{
				GRN_TEXT_PUTC(ctx, &(buffers->keyword), '\\');
			}
			else
			{
				GRN_TEXT_PUTC(ctx, &(buffers->keyword), queryRaw[i + 1]);
				i++;
			}
			break;
		case '%':
		case '_':
			PGrnSearchBuildConditionLikeMatchFlush(
				expression, targetColumn, &(buffers->keyword), &nKeywords);
			break;
		default:
			GRN_TEXT_PUTC(ctx, &(buffers->keyword), queryRaw[i]);
			break;
		}
	}

	PGrnSearchBuildConditionLikeMatchFlush(
		expression, targetColumn, &(buffers->keyword), &nKeywords);
	if (nKeywords == 0)
	{
		PGrnExprAppendObject(expression,
							 grn_ctx_get(ctx, "all_records", -1),
							 GRN_OP_PUSH,
							 1,
							 tag,
							 NULL);
		PGrnExprAppendOp(expression, GRN_OP_CALL, 0, tag, NULL);
	}
}

static void
PGrnSearchBuildConditionLikeRegexp(PGrnSearchData *data,
								   grn_obj *targetColumn,
								   grn_obj *query)
{
	const char *tag = "[build-condition][like-regexp]";
	grn_obj *expression;
	const char *queryRaw;
	const char *queryRawEnd;
	const char *queryRawCurrent;
	size_t querySize;
	int characterSize;
	bool escaping = false;
	bool lastIsPercent = false;

	expression = data->expression;
	queryRaw = GRN_TEXT_VALUE(query);
	querySize = GRN_TEXT_LEN(query);
	queryRawEnd = queryRaw + querySize;

	GRN_BULK_REWIND(&(buffers->pattern));
	if (queryRaw[0] != '%')
		GRN_TEXT_PUTS(ctx, &(buffers->pattern), "\\A");

	queryRawCurrent = queryRaw;
	while ((characterSize = grn_charlen(ctx, queryRawCurrent, queryRawEnd)) > 0)
	{
		const char *current = queryRawCurrent;
		bool needToAddCharacter = true;

		queryRawCurrent += characterSize;

		if (!escaping && characterSize == 1)
		{
			switch (current[0])
			{
			case '%':
				if (queryRaw == current)
				{
					/* do nothing */
				}
				else if (queryRawCurrent == queryRawEnd)
				{
					lastIsPercent = true;
				}
				else
				{
					GRN_TEXT_PUTS(ctx, &(buffers->pattern), ".*");
				}
				needToAddCharacter = false;
				break;
			case '_':
				GRN_TEXT_PUTC(ctx, &(buffers->pattern), '.');
				needToAddCharacter = false;
				break;
			case '\\':
				escaping = true;
				needToAddCharacter = false;
				break;
			default:
				break;
			}

			if (!needToAddCharacter)
				continue;
		}

		if (characterSize == 1)
		{
			switch (current[0])
			{
			case '\\':
			case '|':
			case '(':
			case ')':
			case '[':
			case ']':
			case '.':
			case '*':
			case '+':
			case '?':
			case '{':
			case '}':
			case '^':
			case '$':
				GRN_TEXT_PUTC(ctx, &(buffers->pattern), '\\');
				GRN_TEXT_PUTC(ctx, &(buffers->pattern), current[0]);
				break;
			default:
				GRN_TEXT_PUTC(ctx, &(buffers->pattern), current[0]);
				break;
			}
		}
		else
		{
			GRN_TEXT_PUT(ctx, &(buffers->pattern), current, characterSize);
		}
		escaping = false;
	}

	if (queryRawCurrent != queryRawEnd)
	{
		PGrnCheckRC(GRN_INVALID_ARGUMENT,
					"%s invalid encoding character exist: <%.*s>",
					tag,
					(int) querySize,
					queryRaw);
	}

	if (!lastIsPercent)
		GRN_TEXT_PUTS(ctx, &(buffers->pattern), "\\z");

	PGrnExprAppendObject(
		expression, targetColumn, GRN_OP_GET_VALUE, 1, tag, NULL);
	PGrnExprAppendConstString(expression,
							  GRN_TEXT_VALUE(&(buffers->pattern)),
							  GRN_TEXT_LEN(&(buffers->pattern)),
							  GRN_OP_PUSH,
							  1,
							  tag);
	PGrnExprAppendOp(expression, GRN_OP_REGEXP, 2, tag, NULL);
}

void
PGrnSearchBuildConditionQuery(PGrnSearchData *data,
							  grn_obj *targetColumn,
							  const char *query,
							  unsigned int querySize)
{
	const char *tag = "[build-condition][query]";
	grn_obj *matchTarget, *matchTargetVariable;
	grn_expr_flags flags = PGRN_EXPR_QUERY_PARSE_FLAGS;

	if (PGrnStringIsEmpty(query, querySize))
	{
		data->isEmptyCondition = true;
		return;
	}

	GRN_EXPR_CREATE_FOR_QUERY(
		ctx, data->sourcesTable, matchTarget, matchTargetVariable);
	GRN_PTR_PUT(ctx, &(data->matchTargets), matchTarget);
	PGrnExprAppendObject(
		matchTarget, targetColumn, GRN_OP_GET_VALUE, 1, tag, NULL);

	flags |= PGrnOptionsGetExprParseFlags(data->index);
	grn_expr_parse(ctx,
				   data->expression,
				   query,
				   querySize,
				   matchTarget,
				   GRN_OP_MATCH,
				   GRN_OP_AND,
				   flags);
	PGrnCheck(
		"%s failed to parse expression: <%.*s>", tag, (int) querySize, query);
}

static void
PGrnSearchBuildConditionPrefixRK(PGrnSearchData *data,
								 grn_obj *targetColumn,
								 const char *prefix,
								 unsigned int prefixSize)
{
	const char *tag = "[build-condition][prefix-rk]";
	grn_obj subFilterScript;

	GRN_TEXT_INIT(&subFilterScript, 0);
	GRN_TEXT_PUTS(ctx, &subFilterScript, "prefix_rk_search(_key, ");
	grn_text_esc(ctx, &subFilterScript, prefix, prefixSize);
	GRN_TEXT_PUTS(ctx, &subFilterScript, ")");

	PGrnExprAppendObject(data->expression,
						 grn_ctx_get(ctx, "sub_filter", -1),
						 GRN_OP_PUSH,
						 1,
						 tag,
						 NULL);
	PGrnExprAppendObject(
		data->expression, targetColumn, GRN_OP_GET_VALUE, 1, tag, NULL);
	PGrnExprAppendConstString(data->expression,
							  GRN_TEXT_VALUE(&subFilterScript),
							  GRN_TEXT_LEN(&subFilterScript),
							  GRN_OP_PUSH,
							  1,
							  tag);
	PGrnExprAppendOp(data->expression, GRN_OP_CALL, 2, tag, NULL);

	GRN_OBJ_FIN(ctx, &subFilterScript);
}

static void
PGrnSearchBuildConditionScript(PGrnSearchData *data,
							   grn_obj *targetColumn,
							   const char *script,
							   unsigned int scriptSize)
{
	const char *tag = "[build-condition][script]";
	grn_obj *matchTarget, *matchTargetVariable;
	grn_expr_flags flags = GRN_EXPR_SYNTAX_SCRIPT;

	GRN_EXPR_CREATE_FOR_QUERY(
		ctx, data->sourcesTable, matchTarget, matchTargetVariable);
	GRN_PTR_PUT(ctx, &(data->matchTargets), matchTarget);
	PGrnExprAppendObject(matchTarget, targetColumn, GRN_OP_PUSH, 1, tag, NULL);

	grn_expr_parse(ctx,
				   data->expression,
				   script,
				   scriptSize,
				   matchTarget,
				   GRN_OP_MATCH,
				   GRN_OP_AND,
				   flags);
	PGrnCheck("%s failed to parse expression", tag);
}

void
PGrnSearchBuildConditionBinaryOperation(PGrnSearchData *data,
										grn_obj *targetColumn,
										grn_obj *value,
										grn_operator operator)
{
	const char *tag = "[build-condition][binary-operation]";
	PGrnExprAppendObject(
		data->expression, targetColumn, GRN_OP_GET_VALUE, 1, tag, NULL);
	PGrnExprAppendConst(data->expression, value, GRN_OP_PUSH, 1, tag);
	PGrnExprAppendOp(data->expression, operator, 2, tag, NULL);
}

static Oid
PGrnSearchSetValueTypeID(StrategyNumber strategy, Form_pg_attribute attribute)
{
	Oid valueTypeID = attribute->atttypid;

	switch (strategy)
	{
	case PGrnContainStrategyNumber:
	case PGrnPrefixInStrategyV2Number:
	case PGrnNotPrefixInStrategyV2Number:
	case PGrnPrefixRKInStrategyV2Number:
	case PGrnQueryInStrategyV2Number:
	case PGrnQueryInStrategyV2DeprecatedNumber:
	case PGrnQueryInStrategyV2Deprecated2Number:
	case PGrnMatchInStrategyV2Number:
	case PGrnMatchInStrategyV2DeprecatedNumber:
	case PGrnRegexpInStrategyV2Number:
		switch (valueTypeID)
		{
		case VARCHAROID:
		case VARCHARARRAYOID:
			valueTypeID = VARCHARARRAYOID;
			break;
		case TEXTOID:
		case TEXTARRAYOID:
			valueTypeID = TEXTARRAYOID;
			break;
		}
		break;
	default:
		switch (valueTypeID)
		{
		case VARCHARARRAYOID:
			valueTypeID = VARCHAROID;
			break;
		case TEXTARRAYOID:
			valueTypeID = TEXTOID;
			break;
		}
		break;
	}
	return valueTypeID;
}

void
PGrnSearchBuildCondition(Relation index, ScanKey key, PGrnSearchData *data)
{
	const char *tag = "[build-condition]";
	TupleDesc desc;
	Form_pg_attribute attribute;
	const char *targetColumnName;
	grn_obj *targetColumn;
	grn_operator operator= GRN_OP_NOP;
	Oid valueTypeID;

	desc = RelationGetDescr(index);
	attribute = TupleDescAttr(desc, key->sk_attno - 1);

	targetColumnName = attribute->attname.data;
	targetColumn =
		PGrnLookupColumn(data->sourcesTable, targetColumnName, ERROR);
	GRN_PTR_PUT(ctx, &(data->targetColumns), targetColumn);

	if (PGrnSearchIsInCondition(key))
	{
		// column &= IN (keyword1, keyword2, ...) in PostgreSQL ->
		// in_values(column, keyword1, keyword2, ...) in Groonga
		PGrnSearchBuildConditionIn(
			data, key, targetColumn, attribute, GRN_OP_EQUAL);
		return;
	}
	if (PGrnSearchIsMatchInCondition(key))
	{
		// column &@ IN (keyword1, keyword2, ...) in PostgreSQL ->
		// column @ keyword1 || column @ keyword2 || ... in Groonga
		//
		// PostgreSQL 18 or later optimizes
		//   column &@ keyword1 OR column &@ keyword2 OR ...
		// to
		//   column &@ IN (keyword1, keyword2, ...)
		// .
		//
		// So this is used for "column &@ IN (keyword1, keyword2,
		// ...)" too with PostgreSQL 18 or later.
		PGrnSearchBuildConditionIn(
			data, key, targetColumn, attribute, GRN_OP_MATCH);
		return;
	}
	if (PGrnSearchIsLikeAnyCondition(key) || PGrnSearchIsILikeAnyCondition(key))
	{
		// PostgreSQL 18 or later optimizes
		//   column LIKE/ILIKE keyword1 OR column LIKE/ILIKE keyword2 OR ...
		// to
		//   column ~~ ANY ('{keyword1, keyword2, ...}'::text[])
		// .
		//
		// So this is used for "column LIKE/ILIKE keyword1 OR column
		// LIKE/ILIKE keyword2 OR ..." too with PostgreSQL 18 or later.
		PGrnSearchBuildConditionIn(
			data, key, targetColumn, attribute, GRN_OP_MATCH);
		return;
	}
	if (PGrnIsForSemanticSearchIndex(index, key->sk_attno - 1))
	{
		PGrnSearchBuildConditionSemanticSearch(
			data, key, targetColumn, attribute);
		return;
	}

	if (key->sk_strategy == PGrnMatchFTSConditionStrategyV2Number ||
		key->sk_strategy == PGrnMatchFTSConditionWithScorersStrategyV2Number ||
		key->sk_strategy == PGrnMatchConditionStrategyV2Number)
	{
		PGrnSearchBuildConditionBinaryOperationCondition(
			data, key, targetColumn, attribute, GRN_OP_MATCH);
		return;
	}

	if (key->sk_strategy == PGrnQueryFTSConditionStrategyV2Number ||
		key->sk_strategy == PGrnQueryFTSConditionWithScorersStrategyV2Number ||
		key->sk_strategy == PGrnEqualQueryFTSConditionStrategyV2Number ||
		key->sk_strategy == PGrnQueryConditionStrategyV2Number ||
		key->sk_strategy == PGrnEqualQueryConditionStrategyV2Number)
	{
		PGrnSearchBuildConditionQueryCondition(
			data, key, targetColumn, attribute);
		return;
	}

	if (key->sk_strategy == PGrnPrefixFTSConditionStrategyV2Number ||
		key->sk_strategy == PGrnPrefixConditionStrategyV2Number)
	{
		PGrnSearchBuildConditionBinaryOperationCondition(
			data, key, targetColumn, attribute, GRN_OP_PREFIX);
		return;
	}

	if (key->sk_strategy == PGrnEqualFTSConditionStrategyV2Number ||
		key->sk_strategy == PGrnEqualConditionStrategyV2Number)
	{
		PGrnSearchBuildConditionBinaryOperationCondition(
			data, key, targetColumn, attribute, GRN_OP_EQUAL);
		return;
	}

	if (key->sk_strategy == PGrnRegexpConditionStrategyV2Number)
	{
		PGrnSearchBuildConditionBinaryOperationCondition(
			data, key, targetColumn, attribute, GRN_OP_REGEXP);
		return;
	}

	if (PGrnAttributeIsJSONB(attribute->atttypid))
	{
		PGrnJSONBBuildSearchCondition(data, index, key, targetColumn);
		return;
	}

	valueTypeID = PGrnSearchSetValueTypeID(key->sk_strategy, attribute);

	switch (key->sk_strategy)
	{
	case PGrnLessStrategyNumber:
		operator= GRN_OP_LESS;
		break;
	case PGrnLessEqualStrategyNumber:
		operator= GRN_OP_LESS_EQUAL;
		break;
	case PGrnEqualStrategyNumber:
	case PGrnEqualStrategyV2Number:
		operator= GRN_OP_EQUAL;
		break;
	case PGrnGreaterEqualStrategyNumber:
		operator= GRN_OP_GREATER_EQUAL;
		break;
	case PGrnGreaterStrategyNumber:
		operator= GRN_OP_GREATER;
		break;
	case PGrnLikeStrategyNumber:
	case PGrnILikeStrategyNumber:
		break;
	case PGrnMatchStrategyNumber:
	case PGrnMatchStrategyV2Number:
		operator= GRN_OP_MATCH;
		break;
	case PGrnQueryStrategyNumber:
	case PGrnQueryStrategyV2Number:
	case PGrnQueryStrategyV2DeprecatedNumber:
	case PGrnEqualQueryStrategyV2Number:
		break;
	case PGrnContainStrategyNumber:
		operator= GRN_OP_MATCH;
		break;
	case PGrnSimilarStrategyV2Number:
	case PGrnSimilarStrategyV2DeprecatedNumber:
		operator= GRN_OP_SIMILAR;
		break;
	case PGrnScriptStrategyV2Number:
		break;
	case PGrnPrefixStrategyV2Number:
	case PGrnPrefixStrategyV2DeprecatedNumber:
	case PGrnPrefixInStrategyV2Number:
	case PGrnNotPrefixInStrategyV2Number:
		operator= GRN_OP_PREFIX;
		break;
	case PGrnPrefixRKStrategyV2Number:
	case PGrnPrefixRKStrategyV2DeprecatedNumber:
	case PGrnPrefixRKInStrategyV2Number:
		break;
	case PGrnRegexpStrategyNumber:
	case PGrnRegexpStrategyV2Number:
	case PGrnRegexpInStrategyV2Number:
		operator= GRN_OP_REGEXP;
		break;
	case PGrnQueryInStrategyV2Number:
	case PGrnQueryInStrategyV2DeprecatedNumber:
	case PGrnQueryInStrategyV2Deprecated2Number:
		break;
	case PGrnMatchInStrategyV2Number:
	case PGrnMatchInStrategyV2DeprecatedNumber:
		operator= GRN_OP_MATCH;
		break;
	case PGrnContainStrategyV2Number:
		operator= GRN_OP_MATCH;
		break;
	default:
		PGrnCheckRC(GRN_INVALID_ARGUMENT,
					"%s unexpected strategy number: %d",
					tag,
					key->sk_strategy);
		break;
	}

	{
		grn_id domain;
		unsigned char flags = 0;
		domain = PGrnPGTypeToGrnType(valueTypeID, &flags);
		grn_obj_reinit(ctx, &(buffers->general), domain, flags);
		PGrnConvertFromData(key->sk_argument, valueTypeID, &(buffers->general));
	}

	switch (key->sk_strategy)
	{
	case PGrnLikeStrategyNumber:
		if (PGrnIsForRegexpSearchIndex(index, key->sk_attno - 1))
			PGrnSearchBuildConditionLikeRegexp(
				data, targetColumn, &(buffers->general));
		else
			PGrnSearchBuildConditionLikeMatch(
				data, targetColumn, &(buffers->general));
		break;
	case PGrnILikeStrategyNumber:
		PGrnSearchBuildConditionLikeMatch(
			data, targetColumn, &(buffers->general));
		break;
	case PGrnQueryStrategyNumber:
	case PGrnQueryStrategyV2Number:
	case PGrnQueryStrategyV2DeprecatedNumber:
	case PGrnEqualQueryStrategyV2Number:
		PGrnSearchBuildConditionQuery(data,
									  targetColumn,
									  GRN_TEXT_VALUE(&(buffers->general)),
									  GRN_TEXT_LEN(&(buffers->general)));
		break;
	case PGrnContainStrategyNumber:
	{
		grn_obj *elements = &(buffers->general);
		grn_obj elementBuffer;
		unsigned int i, n;

		GRN_TEXT_INIT(&elementBuffer, GRN_OBJ_DO_SHALLOW_COPY);
		n = grn_vector_size(ctx, elements);
		for (i = 0; i < n; i++)
		{
			const char *element;
			unsigned int elementSize;

			elementSize =
				grn_vector_get_element(ctx, elements, i, &element, NULL, NULL);
			GRN_TEXT_SET(ctx, &elementBuffer, element, elementSize);
			PGrnSearchBuildConditionBinaryOperation(
				data, targetColumn, &elementBuffer, operator);
			if (i > 0)
				PGrnExprAppendOp(data->expression, GRN_OP_AND, 2, tag, NULL);
		}
		GRN_OBJ_FIN(ctx, &elementBuffer);
		break;
	}
	case PGrnScriptStrategyV2Number:
		PGrnSearchBuildConditionScript(data,
									   targetColumn,
									   GRN_TEXT_VALUE(&(buffers->general)),
									   GRN_TEXT_LEN(&(buffers->general)));
		break;
	case PGrnPrefixRKStrategyV2Number:
	case PGrnPrefixRKStrategyV2DeprecatedNumber:
		PGrnSearchBuildConditionPrefixRK(data,
										 targetColumn,
										 GRN_TEXT_VALUE(&(buffers->general)),
										 GRN_TEXT_LEN(&(buffers->general)));
		break;
	case PGrnPrefixRKInStrategyV2Number:
	{
		grn_obj *prefixes = &(buffers->general);
		unsigned int i, n;

		n = grn_vector_size(ctx, prefixes);
		for (i = 0; i < n; i++)
		{
			const char *prefix;
			unsigned int prefixSize;

			prefixSize =
				grn_vector_get_element(ctx, prefixes, i, &prefix, NULL, NULL);
			PGrnSearchBuildConditionPrefixRK(
				data, targetColumn, prefix, prefixSize);
			if (i > 0)
				PGrnExprAppendOp(data->expression, GRN_OP_OR, 2, tag, NULL);
		}
		break;
	}
	case PGrnQueryInStrategyV2Number:
	case PGrnQueryInStrategyV2DeprecatedNumber:
	case PGrnQueryInStrategyV2Deprecated2Number:
	{
		grn_obj *queries = &(buffers->general);
		unsigned int i, n;

		n = grn_vector_size(ctx, queries);
		for (i = 0; i < n; i++)
		{
			const char *query;
			unsigned int querySize;

			querySize =
				grn_vector_get_element(ctx, queries, i, &query, NULL, NULL);
			PGrnSearchBuildConditionQuery(data, targetColumn, query, querySize);
			if (i > 0)
				PGrnExprAppendOp(data->expression, GRN_OP_OR, 2, tag, NULL);
		}
		break;
	}
	case PGrnPrefixInStrategyV2Number:
	case PGrnMatchInStrategyV2Number:
	case PGrnMatchInStrategyV2DeprecatedNumber:
	case PGrnRegexpInStrategyV2Number:
	{
		grn_obj *keywords = &(buffers->general);
		grn_obj keywordBuffer;
		unsigned int i, n;
		unsigned int nTargetKeywords = 0;

		GRN_TEXT_INIT(&keywordBuffer, GRN_OBJ_DO_SHALLOW_COPY);
		n = grn_vector_size(ctx, keywords);
		for (i = 0; i < n; i++)
		{
			const char *keyword;
			unsigned int keywordSize;

			keywordSize =
				grn_vector_get_element(ctx, keywords, i, &keyword, NULL, NULL);
			GRN_TEXT_SET(ctx, &keywordBuffer, keyword, keywordSize);
			if (keywordSize == 0 && operator== GRN_OP_REGEXP)
				continue;

			PGrnSearchBuildConditionBinaryOperation(
				data, targetColumn, &keywordBuffer, operator);
			if (nTargetKeywords > 0)
				PGrnExprAppendOp(data->expression, GRN_OP_OR, 2, tag, NULL);
			nTargetKeywords++;
		}
		GRN_OBJ_FIN(ctx, &keywordBuffer);
		break;
	}
	case PGrnNotPrefixInStrategyV2Number:
	{
		grn_obj *keywords = &(buffers->general);
		grn_obj keywordBuffer;
		unsigned int i, n;

		if (data->nExpressions == 0)
		{
			PGrnExprAppendObject(data->expression,
								 grn_ctx_get(ctx, "all_records", -1),
								 GRN_OP_PUSH,
								 1,
								 tag,
								 NULL);
			PGrnExprAppendOp(data->expression, GRN_OP_CALL, 0, tag, NULL);
		}

		GRN_TEXT_INIT(&keywordBuffer, GRN_OBJ_DO_SHALLOW_COPY);
		n = grn_vector_size(ctx, keywords);
		for (i = 0; i < n; i++)
		{
			const char *keyword;
			unsigned int keywordSize;

			keywordSize =
				grn_vector_get_element(ctx, keywords, i, &keyword, NULL, NULL);
			GRN_TEXT_SET(ctx, &keywordBuffer, keyword, keywordSize);
			PGrnSearchBuildConditionBinaryOperation(
				data, targetColumn, &keywordBuffer, operator);
			PGrnExprAppendOp(data->expression, GRN_OP_AND_NOT, 2, tag, NULL);
		}
		GRN_OBJ_FIN(ctx, &keywordBuffer);
		break;
	}
	default:
		if (operator== GRN_OP_REGEXP && GRN_TEXT_LEN(&(buffers->general)) == 0)
		{
			data->isEmptyCondition = true;
			return;
		}
		PGrnSearchBuildConditionBinaryOperation(
			data, targetColumn, &(buffers->general), operator);
		break;
	}
}

static void
PGrnSearchBuildConditions(IndexScanDesc scan,
						  PGrnScanOpaque so,
						  PGrnSearchData *data)
{
	const char *tag = "[build-conditions]";
	Relation index = scan->indexRelation;
	int i;

	PGrnAutoCloseUseIndex(index);

	for (i = 0; i < scan->numberOfKeys; i++)
	{
		ScanKey key = &(scan->keyData[i]);

		/* NULL key is not supported */
		if (key->sk_flags & SK_ISNULL)
			continue;

		PGrnSearchBuildCondition(index, key, data);

		if (data->isEmptyCondition)
			return;

		switch (key->sk_strategy)
		{
		case PGrnNotPrefixInStrategyV2Number:
			break;
		default:
			if (data->nExpressions > 0)
				PGrnExprAppendOp(data->expression, GRN_OP_AND, 2, tag, NULL);
			break;
		}
		data->nExpressions++;
	}
}

void
PGrnSearchDataInit(PGrnSearchData *data, Relation index, grn_obj *sourcesTable)
{
	data->index = index;
	data->sourcesTable = sourcesTable;
	GRN_PTR_INIT(&(data->matchTargets), GRN_OBJ_VECTOR, GRN_ID_NIL);
	GRN_PTR_INIT(&(data->targetColumns), GRN_OBJ_VECTOR, GRN_ID_NIL);
	GRN_UINT32_INIT(&(data->sectionID), 0);

	GRN_EXPR_CREATE_FOR_QUERY(
		ctx, sourcesTable, data->expression, data->expressionVariable);
	data->isEmptyCondition = false;
	data->fuzzyMaxDistanceRatio = 0.0;
	data->nExpressions = 0;
}

void
PGrnSearchDataFree(PGrnSearchData *data)
{
	unsigned int i;
	unsigned int nMatchTargets;
	unsigned int nTargetColumns;

	grn_obj_unlink(ctx, data->expression);

	nMatchTargets = GRN_BULK_VSIZE(&(data->matchTargets)) / sizeof(grn_obj *);
	for (i = 0; i < nMatchTargets; i++)
	{
		grn_obj *matchTarget = GRN_PTR_VALUE_AT(&(data->matchTargets), i);
		grn_obj_unlink(ctx, matchTarget);
	}
	GRN_OBJ_FIN(ctx, &(data->matchTargets));

	nTargetColumns = GRN_BULK_VSIZE(&(data->targetColumns)) / sizeof(grn_obj *);
	for (i = 0; i < nTargetColumns; i++)
	{
		grn_obj *targetColumn = GRN_PTR_VALUE_AT(&(data->targetColumns), i);
		grn_obj_unlink(ctx, targetColumn);
	}
	GRN_OBJ_FIN(ctx, &(data->targetColumns));

	GRN_OBJ_FIN(ctx, &(data->sectionID));
}

static void
PGrnSearch(IndexScanDesc scan)
{
	PGrnScanOpaque so = (PGrnScanOpaque) scan->opaque;
	PGrnSearchData data;

	if (scan->numberOfKeys == 0)
		return;

	PGrnSearchDataInit(&data, so->index, so->sourcesTable);
	PG_TRY();
	{
		PGrnSearchBuildConditions(scan, so, &data);
	}
	PG_CATCH();
	{
		PGrnSearchDataFree(&data);
		PG_RE_THROW();
	}
	PG_END_TRY();

	/* TODO: Add NULL check for so->searched. */
	so->searched =
		grn_table_create(ctx,
						 NULL,
						 0,
						 NULL,
						 GRN_OBJ_TABLE_HASH_KEY | GRN_OBJ_WITH_SUBREC,
						 so->sourcesTable,
						 0);
	if (!data.isEmptyCondition)
	{
		grn_table_selector *table_selector = grn_table_selector_open(
			ctx, so->sourcesTable, data.expression, GRN_OP_OR);
		grn_table_selector_set_fuzzy_max_distance_ratio(
			ctx, table_selector, data.fuzzyMaxDistanceRatio);
		grn_table_selector_select(ctx, table_selector, so->searched);
		grn_table_selector_close(ctx, table_selector);
	}
	PGrnSearchDataFree(&data);
}

static bool
PGrnSortIsSimilarDistance(ScanKey key)
{
	return key->sk_strategy == PGrnSimilarDistanceConditionStrategyV2Number;
}

static void
PGrnSort(IndexScanDesc scan)
{
	const char *tag = "[sort]";
	PGrnScanOpaque so = (PGrnScanOpaque) scan->opaque;
	int nSortKeys;
	ScanKey keys;
	grn_obj *targetTable;
	grn_table_sort_key *sortKeys;
	TupleDesc desc;

	if (scan->numberOfOrderBys == 0)
	{
		/* Workaround: We don't know why 'WHERE id = ANY(ARRAY[...])
		 * ORDER BY id ASC' doesn't set scan->numberOfOrderBys but
		 * sorted result is required. We use scan->keyData for this
		 * case. */
		if (scan->numberOfKeys != 1)
		{
			/* We use this workaround only for one key because we
			 * don't know whether this is needed for multiple keys
			 * case. */
			return;
		}
		nSortKeys = scan->numberOfKeys;
		keys = scan->keyData;
	}
	else
	{
		nSortKeys = scan->numberOfOrderBys;
		keys = scan->orderByData;
	}

	{
		int i;
		for (i = 0; i < nSortKeys; i++)
		{
			ScanKey key = &(keys[i]);
			if (!(PGrnSearchIsInCondition(key) ||
				  PGrnSortIsSimilarDistance(key)))
			{
				// TODO: Set scan->xs_recheckorderby = true and
				// scan->xs_orderbyvals/scan->xs_orderbynulls.
				return;
			}
		}
	}

	if (so->searched)
		targetTable = so->searched;
	else
		targetTable = so->sourcesTable;

	so->sorted = grn_table_create(
		ctx, NULL, 0, NULL, GRN_OBJ_TABLE_NO_KEY, NULL, targetTable);

	scan->xs_recheckorderby = false;

	sortKeys = palloc(sizeof(grn_table_sort_key) * nSortKeys);
	desc = RelationGetDescr(scan->indexRelation);

	{
		int i;
		for (i = 0; i < nSortKeys; i++)
		{
			ScanKey key = &(keys[i]);
			Form_pg_attribute attribute =
				TupleDescAttr(desc, key->sk_attno - 1);
			const char *targetColumnName = attribute->attname.data;
			grn_obj *targetColumn = grn_obj_column(
				ctx, targetTable, targetColumnName, strlen(targetColumnName));
			if (PGrnSearchIsInCondition(key))
			{
				sortKeys[i].key = targetColumn;
				sortKeys[i].flags = GRN_TABLE_SORT_ASC;
			}
			else if (PGrnSortIsSimilarDistance(key))
			{
				HeapTupleHeader header =
					DatumGetHeapTupleHeader(key->sk_argument);
				PGrnCondition condition;
				grn_obj *sorter;
				grn_obj *variable;

				PGrnConditionDeconstruct(&condition, header);

				GRN_EXPR_CREATE_FOR_QUERY(ctx, targetTable, sorter, variable);
				PGrnExprAppendObject(sorter,
									 PGrnLookup("language_model_knn", ERROR),
									 GRN_OP_PUSH,
									 1,
									 tag,
									 NULL);
				PGrnExprAppendObject(
					sorter, targetColumn, GRN_OP_GET_VALUE, 1, tag, NULL);
				grn_expr_take_obj(ctx, sorter, targetColumn);
				PGrnExprAppendConstString(sorter,
										  VARDATA_ANY(condition.query),
										  VARSIZE_ANY_EXHDR(condition.query),
										  GRN_OP_PUSH,
										  1,
										  tag);
				// TODO: Add support for n_probes.
				PGrnExprAppendOp(sorter, GRN_OP_CALL, 2, tag, NULL);
				sortKeys[i].key = sorter;
				sortKeys[i].flags = GRN_TABLE_SORT_DESC;
			}
			sortKeys[i].offset = 0;
		}
	}
	grn_table_sort(ctx, targetTable, 0, -1, so->sorted, sortKeys, nSortKeys);
	{
		int i;
		for (i = 0; i < nSortKeys; i++)
		{
			if (grn_obj_is_accessor(ctx, sortKeys[i].key) ||
				grn_obj_is_expr(ctx, sortKeys[i].key))
			{
				grn_obj_close(ctx, sortKeys[i].key);
			}
		}
	}
	pfree(sortKeys);
}

static void
PGrnOpenTableCursor(IndexScanDesc scan, ScanDirection dir)
{
	const char *tag = "[cursor][open]";
	PGrnScanOpaque so = (PGrnScanOpaque) scan->opaque;
	grn_obj *table;
	int offset = 0;
	int limit = -1;
	int flags = 0;

	table = so->sorted;
	if (!table)
		table = so->searched;
	if (!table)
		table = so->sourcesTable;

	if (ScanDirectionIsBackward(dir))
		flags |= GRN_CURSOR_DESCENDING;
	else
		flags |= GRN_CURSOR_ASCENDING;

	if (!grn_obj_is_table(ctx, table))
	{
		GRN_LOG(ctx,
				GRN_LOG_DEBUG,
				"pgroonga: %s target table is invalid: "
				"<%p>: <%p>:<%p>:<%p>:<%p>",
				tag,
				so,
				table,
				so->sorted,
				so->searched,
				so->sourcesTable);
	}
	so->tableCursor = grn_table_cursor_open(
		ctx, table, NULL, 0, NULL, 0, offset, limit, flags);
	PGrnCheck("%s failed to open cursor", tag);
	if (so->sourcesTable->header.type == GRN_TABLE_NO_KEY)
	{
		so->ctidAccessor = grn_obj_column(ctx,
										  table,
										  PGrnSourcesCtidColumnName,
										  PGrnSourcesCtidColumnNameLength);
	}
	else
	{
		so->ctidAccessor = grn_obj_column(
			ctx, table, GRN_COLUMN_NAME_KEY, GRN_COLUMN_NAME_KEY_LEN);
	}
	if (so->searched)
	{
		so->scoreAccessor = grn_obj_column(ctx,
										   so->searched,
										   GRN_COLUMN_NAME_SCORE,
										   GRN_COLUMN_NAME_SCORE_LEN);
	}
}

static bool
PGrnIsMeaningfullMaxBorderValue(grn_obj *currentValue,
								grn_obj *newValue,
								int flags,
								StrategyNumber strategy)
{
	if (((flags & GRN_CURSOR_LT) == GRN_CURSOR_LT) &&
		strategy == PGrnLessEqualStrategyNumber)
	{
		return grn_operator_exec_greater_equal(ctx, currentValue, newValue);
	}
	else
	{
		return grn_operator_exec_greater(ctx, currentValue, newValue);
	}
}

static bool
PGrnIsMeaningfullMinBorderValue(grn_obj *currentValue,
								grn_obj *newValue,
								int flags,
								StrategyNumber strategy)
{
	if (((flags & GRN_CURSOR_GT) == GRN_CURSOR_GT) &&
		strategy == PGrnGreaterEqualStrategyNumber)
	{
		return grn_operator_exec_less_equal(ctx, currentValue, newValue);
	}
	else
	{
		return grn_operator_exec_less(ctx, currentValue, newValue);
	}
}

static void
PGrnFillBorder(IndexScanDesc scan,
			   void **min,
			   unsigned int *minSize,
			   void **max,
			   unsigned int *maxSize,
			   int *flags)
{
	const char *tag = "[range][fill-border]";
	Relation index = scan->indexRelation;
	TupleDesc desc;
	PGrnScanOpaque so = (PGrnScanOpaque) scan->opaque;
	grn_obj *minBorderValue;
	grn_obj *maxBorderValue;
	int i;

	desc = RelationGetDescr(index);

	minBorderValue = &(so->minBorderValue);
	maxBorderValue = &(so->maxBorderValue);
	for (i = 0; i < scan->numberOfKeys; i++)
	{
		ScanKey key = &(scan->keyData[i]);
		AttrNumber attrNumber;
		Form_pg_attribute attribute;
		grn_id domain;

		attrNumber = key->sk_attno - 1;
		attribute = TupleDescAttr(desc, attrNumber);

		domain = PGrnGetType(index, attrNumber, NULL);
		switch (key->sk_strategy)
		{
		case PGrnLessStrategyNumber:
		case PGrnLessEqualStrategyNumber:
			if (maxBorderValue->header.type != GRN_DB_VOID)
			{
				grn_obj_reinit(ctx, &(buffers->general), domain, 0);
				PGrnConvertFromData(
					key->sk_argument, attribute->atttypid, &(buffers->general));
				if (!PGrnIsMeaningfullMaxBorderValue(maxBorderValue,
													 &(buffers->general),
													 *flags,
													 key->sk_strategy))
				{
					continue;
				}
			}
			grn_obj_reinit(ctx, maxBorderValue, domain, 0);
			PGrnConvertFromData(
				key->sk_argument, attribute->atttypid, maxBorderValue);
			*max = GRN_BULK_HEAD(maxBorderValue);
			*maxSize = GRN_BULK_VSIZE(maxBorderValue);
			*flags &= ~(GRN_CURSOR_LT | GRN_CURSOR_LE);
			if (key->sk_strategy == PGrnLessStrategyNumber)
			{
				*flags |= GRN_CURSOR_LT;
			}
			else
			{
				*flags |= GRN_CURSOR_LE;
			}
			break;
		case PGrnGreaterEqualStrategyNumber:
		case PGrnGreaterStrategyNumber:
			if (minBorderValue->header.type != GRN_DB_VOID)
			{
				grn_obj_reinit(ctx, &(buffers->general), domain, 0);
				PGrnConvertFromData(
					key->sk_argument, attribute->atttypid, &(buffers->general));
				if (!PGrnIsMeaningfullMinBorderValue(minBorderValue,
													 &(buffers->general),
													 *flags,
													 key->sk_strategy))
				{
					continue;
				}
			}
			grn_obj_reinit(ctx, minBorderValue, domain, 0);
			PGrnConvertFromData(
				key->sk_argument, attribute->atttypid, minBorderValue);
			*min = GRN_BULK_HEAD(minBorderValue);
			*minSize = GRN_BULK_VSIZE(minBorderValue);
			*flags &= ~(GRN_CURSOR_GT | GRN_CURSOR_GE);
			if (key->sk_strategy == PGrnGreaterEqualStrategyNumber)
			{
				*flags |= GRN_CURSOR_GE;
			}
			else
			{
				*flags |= GRN_CURSOR_GT;
			}
			break;
		default:
			PGrnCheckRC(GRN_INVALID_ARGUMENT,
						"%s unexpected strategy number for range search: %d",
						tag,
						key->sk_strategy);
			break;
		}
	}
}

static void
PGrnRangeSearch(IndexScanDesc scan, ScanDirection dir)
{
	PGrnScanOpaque so = (PGrnScanOpaque) scan->opaque;
	void *min = NULL;
	unsigned int minSize = 0;
	void *max = NULL;
	unsigned int maxSize = 0;
	int offset = 0;
	int limit = -1;
	int flags = 0;
	grn_id indexCursorMin = GRN_ID_NIL;
	grn_id indexCursorMax = GRN_ID_MAX;
	int indexCursorFlags = 0;
	grn_obj *indexColumn;
	grn_obj *lexicon;
	int i;
	unsigned int nthAttribute = 0;

	PGrnFillBorder(scan, &min, &minSize, &max, &maxSize, &flags);

	if (ScanDirectionIsBackward(dir))
		flags |= GRN_CURSOR_DESCENDING;
	else
		flags |= GRN_CURSOR_ASCENDING;

	for (i = 0; i < scan->numberOfKeys; i++)
	{
		ScanKey key = &(scan->keyData[i]);
		nthAttribute = key->sk_attno - 1;
		break;
	}
	indexColumn =
		PGrnLookupIndexColumn(scan->indexRelation, nthAttribute, ERROR);
	lexicon = grn_column_table(ctx, indexColumn);

	so->tableCursor = grn_table_cursor_open(
		ctx, lexicon, min, minSize, max, maxSize, offset, limit, flags);
	so->indexCursor = grn_index_cursor_open(ctx,
											so->tableCursor,
											indexColumn,
											indexCursorMin,
											indexCursorMax,
											indexCursorFlags);
	if (so->sourcesTable->header.type == GRN_TABLE_NO_KEY)
	{
		so->ctidAccessor = grn_obj_column(ctx,
										  so->sourcesTable,
										  PGrnSourcesCtidColumnName,
										  PGrnSourcesCtidColumnNameLength);
	}
	else
	{
		so->ctidAccessor = grn_obj_column(ctx,
										  so->sourcesTable,
										  GRN_COLUMN_NAME_KEY,
										  GRN_COLUMN_NAME_KEY_LEN);
	}
}

static bool
PGrnIsRangeSearchable(IndexScanDesc scan)
{
	int i;
	AttrNumber previousAttrNumber = InvalidAttrNumber;

	if (scan->numberOfKeys == 0)
	{
		TupleDesc desc = RelationGetDescr(scan->indexRelation);
		grn_obj *indexColumn;
		grn_obj *lexicon;
		grn_obj *tokenizer;

		if (desc->natts == 1)
		{
			Form_pg_attribute attribute = TupleDescAttr(desc, 0);
			if (PGrnAttributeIsJSONB(attribute->atttypid))
				return false;
		}

		indexColumn = PGrnLookupIndexColumn(scan->indexRelation, 0, ERROR);
		lexicon = grn_column_table(ctx, indexColumn);
		tokenizer =
			grn_obj_get_info(ctx, lexicon, GRN_INFO_DEFAULT_TOKENIZER, NULL);
		if (tokenizer)
		{
			return false;
		}
	}

	for (i = 0; i < scan->numberOfKeys; i++)
	{
		ScanKey key = &(scan->keyData[i]);

		if (previousAttrNumber == InvalidAttrNumber)
		{
			previousAttrNumber = key->sk_attno;
		}
		if (key->sk_attno != previousAttrNumber)
		{
			return false;
		}

		switch (key->sk_strategy)
		{
		case PGrnLessStrategyNumber:
		case PGrnLessEqualStrategyNumber:
		case PGrnGreaterStrategyNumber:
		case PGrnGreaterEqualStrategyNumber:
			break;
		default:
			return false;
			break;
		}
	}

	if (scan->numberOfOrderBys > scan->numberOfKeys)
		return false;
	for (i = 0; i < scan->numberOfOrderBys; i++)
	{
		ScanKey key = &(scan->keyData[i]);
		ScanKey sortKey = &(scan->orderByData[i]);
		if (key->sk_attno != sortKey->sk_attno)
			return false;
	}

	return true;
}

static void
PGrnEnsureCursorOpened(IndexScanDesc scan, ScanDirection dir, bool needSort)
{
	PGrnScanOpaque so = (PGrnScanOpaque) scan->opaque;

	scan->xs_recheck = false;

	{
		int i;
		for (i = 0; i < scan->numberOfKeys; i++)
		{
			ScanKey key = &(scan->keyData[i]);
			if (key->sk_strategy == PGrnLikeStrategyNumber ||
				key->sk_strategy == PGrnILikeStrategyNumber)
			{
				scan->xs_recheck = true;
				break;
			}
		}
	}

	if (so->indexCursor)
		return;
	if (so->tableCursor)
		return;

	if (PGrnIsRangeSearchable(scan))
	{
		PGrnRangeSearch(scan, dir);
	}
	else
	{
		PGrnSearch(scan);
		if (needSort)
			PGrnSort(scan);
		PGrnOpenTableCursor(scan, dir);
	}
}

static grn_id
PGrnScanOpaqueResolveID(PGrnScanOpaque so)
{
	grn_id recordID = so->currentID;

	if (so->sorted)
	{
		GRN_BULK_REWIND(&(buffers->general));
		grn_obj_get_value(ctx, so->sorted, recordID, &(buffers->general));
		recordID = GRN_RECORD_VALUE(&(buffers->general));
	}
	if (so->searched)
	{
		grn_table_get_key(
			ctx, so->searched, recordID, &recordID, sizeof(grn_id));
	}

	return recordID;
}

static bool pgroonga_canreturn(Relation index, int nthAttribute);

static void
PGrnGetTupleFillIndexTuple(PGrnScanOpaque so, IndexScanDesc scan)
{
	MemoryContext oldMemoryContext;
	TupleDesc desc;
	Datum *values;
	bool *isNulls;
	grn_id recordID;
	unsigned int i;

	MemoryContextReset(so->memoryContext);
	oldMemoryContext = MemoryContextSwitchTo(so->memoryContext);

	desc = RelationGetDescr(so->index);
	scan->xs_itupdesc = desc;

	values = palloc(sizeof(Datum) * desc->natts);
	isNulls = palloc(sizeof(bool) * desc->natts);

	recordID = PGrnScanOpaqueResolveID(so);

	for (i = 0; i < desc->natts; i++)
	{
		Form_pg_attribute attribute = TupleDescAttr(desc, i);
		NameData *name;
		grn_obj *dataColumn;

		if (GRN_BOOL_VECTOR_SIZE(&(so->canReturns)) <= i)
		{
			unsigned int j;
			for (j = GRN_BOOL_VECTOR_SIZE(&(so->canReturns)); j <= i; j++)
			{
				bool can = pgroonga_canreturn(so->index, j);
				GRN_BOOL_PUT(ctx, &(so->canReturns), can);
			}
		}

		if (!GRN_BOOL_VALUE_AT(&(so->canReturns), i))
		{
			values[i] = PointerGetDatum(NULL);
			isNulls[i] = true;
			continue;
		}

		name = &(attribute->attname);
		dataColumn = PGrnLookupColumn(so->sourcesTable, name->data, ERROR);
		GRN_BULK_REWIND(&(buffers->general));
		grn_obj_get_value(ctx, dataColumn, recordID, &(buffers->general));
		values[i] =
			PGrnConvertToDatum(&(buffers->general), attribute->atttypid);
		isNulls[i] = false;
		grn_obj_unlink(ctx, dataColumn);
	}

	scan->xs_itup = index_form_tuple(scan->xs_itupdesc, values, isNulls);

	MemoryContextSwitchTo(oldMemoryContext);
}

static bool
pgroonga_gettuple_internal(IndexScanDesc scan, ScanDirection direction)
{
	const char *tag = "pgroonga: [get-tuple]";
	PGrnScanOpaque so = (PGrnScanOpaque) scan->opaque;
	bool found = false;

	if (scan->parallel_scan)
	{
		if (!PGrnParallelScanAcquire(scan))
			return false;
	}

	PGrnEnsureCursorOpened(scan, direction, true);

	if (scan->kill_prior_tuple && so->currentID != GRN_ID_NIL &&
		PGrnIsWritable()
	/* StandbyMode isn't exported on Windows in PostgreSQL < 15. */
#if !defined(_WIN32) || PG_VERSION_NUM >= 150000
		&& !StandbyMode
#endif
	)
	{
		grn_id recordID;
		uint64_t packedCtid;

		recordID = PGrnScanOpaqueResolveID(so);
		GRN_BULK_REWIND(&(buffers->ctid));
		grn_obj_get_value(
			ctx, so->ctidAccessor, so->currentID, &(buffers->ctid));
		if (GRN_BULK_VSIZE(&(buffers->ctid)) == 0)
		{
			NameData tableName;
			GRN_LOG(ctx,
					GRN_LOG_DEBUG,
					"%s[delete][nonexistent] <%s>(%u): <%u> -> <%u>",
					tag,
					PGrnPGGetRelationNameByID(so->dataTableID, tableName.data),
					so->dataTableID,
					so->currentID,
					recordID);
		}
		else
		{
			packedCtid = GRN_UINT64_VALUE(&(buffers->ctid));
			if (grn_logger_pass(ctx, GRN_LOG_DEBUG))
			{
				NameData tableName;
				ItemPointerData ctid = PGrnCtidUnpack(packedCtid);
				GRN_LOG(
					ctx,
					GRN_LOG_DEBUG,
					"%s[delete] "
					"<%s>(%u): <%u> -> <%u>: <(%u,%u),%u>: <%" PRIu64 ">",
					tag,
					PGrnPGGetRelationNameByID(so->dataTableID, tableName.data),
					so->dataTableID,
					so->currentID,
					recordID,
					ctid.ip_blkid.bi_hi,
					ctid.ip_blkid.bi_lo,
					ctid.ip_posid,
					packedCtid);
			}
			grn_table_delete_by_id(ctx, so->sourcesTable, recordID);

			PGrnWALDelete(so->index,
						  so->sourcesTable,
						  (const char *) &packedCtid,
						  sizeof(uint64_t));
		}
	}

	while (!found)
	{
		if (so->indexCursor)
		{
			grn_posting *posting;
			grn_id termID;
			grn_id id = GRN_ID_NIL;
			posting = grn_index_cursor_next(ctx, so->indexCursor, &termID);
			if (posting)
				id = posting->rid;
			so->currentID = id;
		}
		else
		{
			so->currentID = grn_table_cursor_next(ctx, so->tableCursor);
		}

		if (so->currentID == GRN_ID_NIL)
			break;

		{
			uint64_t packedCtid;
			ItemPointerData ctid;
			bool valid;

			GRN_BULK_REWIND(&(buffers->ctid));
			grn_obj_get_value(
				ctx, so->ctidAccessor, so->currentID, &(buffers->ctid));
			if (GRN_BULK_VSIZE(&(buffers->ctid)) == 0)
			{
				NameData tableName;
				GRN_LOG(
					ctx,
					GRN_LOG_DEBUG,
					"%s[nonexistent] <%s>(%u): <%u> -> <%u>",
					tag,
					PGrnPGGetRelationNameByID(so->dataTableID, tableName.data),
					so->dataTableID,
					so->currentID,
					PGrnScanOpaqueResolveID(so));
				continue;
			}

			packedCtid = GRN_UINT64_VALUE(&(buffers->ctid));
			ctid = PGrnCtidUnpack(packedCtid);
			valid = ItemPointerIsValid(&ctid);

			{
				NameData tableName;
				GRN_LOG(
					ctx,
					GRN_LOG_DEBUG,
					"%s <%s>(%u): <%u> -> <%u>: "
					"<(%u,%u),%u>: <%" PRIu64 ">: <%s>",
					tag,
					PGrnPGGetRelationNameByID(so->dataTableID, tableName.data),
					so->dataTableID,
					so->currentID,
					PGrnScanOpaqueResolveID(so),
					ctid.ip_blkid.bi_hi,
					ctid.ip_blkid.bi_lo,
					ctid.ip_posid,
					packedCtid,
					valid ? "true" : "false");
			}

			if (!valid)
				continue;

			scan->xs_heaptid = ctid;
		}

		if (scan->xs_want_itup)
			PGrnGetTupleFillIndexTuple(so, scan);

		found = true;
	}

	return found;
}

static bool
pgroonga_gettuple(IndexScanDesc scan, ScanDirection direction)
{
	bool found = false;

	/* We should not call PGrnEnsureLatestDB() here. See the
	 * PGrnEnsureLatestDB() comment for details. */
	/* PGrnEnsureLatestDB(); */

	/* This may slow down with large result set. */
	/* PGRN_TRACE_LOG_ENTER(); */

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabled(scan->heapRelation->rd_id));
	{
		found = pgroonga_gettuple_internal(scan, direction);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		found = pgroonga_gettuple_internal(scan, direction);
	}
	PGRN_RLS_ENABLED_END();

	/* This may slow down with large result set. */
	/* PGRN_TRACE_LOG_EXIT(); */

	return found;
}

static int64
pgroonga_getbitmap_internal(IndexScanDesc scan, TIDBitmap *tbm)
{
	const char *tag = "pgroonga: [get-bitmap]";
	PGrnScanOpaque so = (PGrnScanOpaque) scan->opaque;
	int64 nRecords = 0;

	if (scan->parallel_scan)
	{
		if (!PGrnParallelScanAcquire(scan))
		{
			return 0;
		}
	}

	/* We should not call PGrnEnsureLatestDB() here because
	 * PGrnScanOpaque refers Groonga objects and PGrnEnsureLatestDB()
	 * may close referred Groonga objects. */
	/* PGrnEnsureLatestDB(); */

	PGrnEnsureCursorOpened(scan, ForwardScanDirection, false);

	if (so->indexCursor)
	{
		grn_posting *posting;
		grn_id termID;
		while ((posting = grn_index_cursor_next(ctx, so->indexCursor, &termID)))
		{
			uint64_t packedCtid;
			ItemPointerData ctid;

			so->currentID = posting->rid;
			GRN_BULK_REWIND(&(buffers->ctid));
			grn_obj_get_value(
				ctx, so->ctidAccessor, so->currentID, &(buffers->ctid));
			if (GRN_BULK_VSIZE(&(buffers->ctid)) == 0)
			{
				GRN_LOG(ctx,
						GRN_LOG_DEBUG,
						"%s[index-cursor][nonexistent] <%s>(%u): <%u>",
						tag,
						so->index->rd_rel->relname.data,
						so->index->rd_id,
						so->currentID);
				continue;
			}

			packedCtid = GRN_UINT64_VALUE(&(buffers->ctid));
			ctid = PGrnCtidUnpack(packedCtid);
			GRN_LOG(ctx,
					GRN_LOG_DEBUG,
					"%s[index-cursor] <%s>(%u): <%u>: <(%u,%u),%u>(%" PRIu64
					")",
					tag,
					so->index->rd_rel->relname.data,
					so->index->rd_id,
					so->currentID,
					ctid.ip_blkid.bi_hi,
					ctid.ip_blkid.bi_lo,
					ctid.ip_posid,
					packedCtid);
			if (!ItemPointerIsValid(&ctid))
				continue;
			tbm_add_tuples(tbm, &ctid, 1, scan->xs_recheck);
			nRecords++;
		}
	}
	else
	{
		while (true)
		{
			uint64_t packedCtid;
			ItemPointerData ctid;

			so->currentID = grn_table_cursor_next(ctx, so->tableCursor);
			if (so->currentID == GRN_ID_NIL)
				break;

			GRN_BULK_REWIND(&(buffers->ctid));
			grn_obj_get_value(
				ctx, so->ctidAccessor, so->currentID, &(buffers->ctid));
			if (GRN_BULK_VSIZE(&(buffers->ctid)) == 0)
			{
				GRN_LOG(ctx,
						GRN_LOG_DEBUG,
						"%s[nonexistent] <%s>(%u): <%u>",
						tag,
						so->index->rd_rel->relname.data,
						so->index->rd_id,
						PGrnScanOpaqueResolveID(so));
				continue;
			}

			packedCtid = GRN_UINT64_VALUE(&(buffers->ctid));
			ctid = PGrnCtidUnpack(packedCtid);
			GRN_LOG(ctx,
					GRN_LOG_DEBUG,
					"%s <%s>(%u): <%u>: <(%u,%u),%u>(%" PRIu64 ")",
					tag,
					so->index->rd_rel->relname.data,
					so->index->rd_id,
					PGrnScanOpaqueResolveID(so),
					ctid.ip_blkid.bi_hi,
					ctid.ip_blkid.bi_lo,
					ctid.ip_posid,
					packedCtid);
			if (!ItemPointerIsValid(&ctid))
				continue;
			tbm_add_tuples(tbm, &ctid, 1, scan->xs_recheck);
			nRecords++;
		}
	}

	return nRecords;
}

static int64
pgroonga_getbitmap(IndexScanDesc scan, TIDBitmap *tbm)
{
	int64 nRecords = 0;
	bool enabled;

	PGRN_TRACE_LOG_ENTER();

	enabled = PGrnCheckRLSEnabled(scan->indexRelation->rd_index->indrelid);
	PGRN_RLS_ENABLED_IF(enabled);
	{
		nRecords = pgroonga_getbitmap_internal(scan, tbm);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		nRecords = pgroonga_getbitmap_internal(scan, tbm);
	}
	PGRN_RLS_ENABLED_END();

	PGRN_TRACE_LOG_EXIT();

	return nRecords;
}

static void
pgroonga_rescan(IndexScanDesc scan,
				ScanKey keys,
				int nKeys,
				ScanKey orderBys,
				int nOrderBys)
{
	PGrnScanOpaque so = (PGrnScanOpaque) scan->opaque;

	PGRN_TRACE_LOG_ENTER();

	MemoryContextReset(so->memoryContext);
	/* We should not call PGrnEnsureLatestDB() here. See the
	 * PGrnEnsureLatestDB() comment for details. */
	/* PGrnEnsureLatestDB(); */
	PGrnScanOpaqueReinit(so);

	if (keys && scan->numberOfKeys > 0)
		memmove(scan->keyData, keys, scan->numberOfKeys * sizeof(ScanKeyData));
	if (orderBys && scan->numberOfOrderBys > 0)
		memmove(scan->orderByData,
				orderBys,
				scan->numberOfOrderBys * sizeof(ScanKeyData));

	PGRN_TRACE_LOG_EXIT();
}

static void
pgroonga_endscan(IndexScanDesc scan)
{
	PGrnScanOpaque so = (PGrnScanOpaque) scan->opaque;
	MemoryContext memoryContext = so->memoryContext;

	PGRN_TRACE_LOG_ENTER();

	GRN_LOG(ctx, GRN_LOG_DEBUG, "pgroonga: [scan][end] <%p>", so);

	PGrnScanOpaqueFin(so);
	MemoryContextDelete(memoryContext);

	PGRN_TRACE_LOG_EXIT();
}

static void
PGrnBuildCallback(Relation index,
				  ItemPointer tid,
				  Datum *values,
				  bool *isnull,
				  bool tupleIsAlive,
				  void *state)
{
	PGrnBuildState bs = (PGrnBuildState) state;
	MemoryContext oldMemoryContext;
	uint32_t recordSize;

	if (!tupleIsAlive)
		return;

	oldMemoryContext = MemoryContextSwitchTo(bs->memoryContext);

	recordSize = PGrnInsert(index,
							bs->sourcesTable,
							bs->sourcesCtidColumn,
							values,
							isnull,
							tid,
							bs->isBulkInsert,
							bs->bulkInsertWALData);
	if (bs->needMaxRecordSizeUpdate && recordSize > bs->maxRecordSize)
	{
		bs->maxRecordSize = recordSize;
	}
	bs->nIndexedTuples++;

	MemoryContextSwitchTo(oldMemoryContext);
	MemoryContextReset(bs->memoryContext);
}

static void
pgroonga_build_copy_source_execute(PGrnCreateData *data,
								   PGrnBuildStateData *bs,
								   bool progress,
								   TableScanDesc scan)
{
	if (bs->isBulkInsert)
	{
		bs->bulkInsertWALData = PGrnWALStart(data->index);
		PGrnWALBulkInsertStart(bs->bulkInsertWALData, bs->sourcesTable);
	}
	/* Disable WAL generation while bulk source table creation for
	 * performance. If PGroonga is crashed while bulk source table
	 * creation, this source table will be removed in the next
	 * VACUUM. So, we don't need crash recovery here. */
	if (bs->walRoleKeep != GRN_WAL_ROLE_NONE)
		grn_ctx_set_wal_role(ctx, GRN_WAL_ROLE_NONE);
	bs->nProcessedHeapTuples = table_index_build_scan(data->heap,
													  data->index,
													  data->indexInfo,
													  true,
													  progress,
													  PGrnBuildCallback,
													  bs,
													  scan);
	if (bs->walRoleKeep != GRN_WAL_ROLE_NONE)
	{
		/* Flush written data so that we can assume that this
		 * source table isn't broken by PGroonga crash in index
		 * creation. */
		grn_obj_flush_recursive(ctx, data->sourcesTable);
		grn_ctx_set_wal_role(ctx, bs->walRoleKeep);
	}
	if (bs->isBulkInsert)
	{
		PGrnWALBulkInsertFinish(bs->bulkInsertWALData);
		PGrnWALFinish(bs->bulkInsertWALData);
		bs->bulkInsertWALData = NULL;
	}
}

static void
pgroonga_build_copy_source_serial(PGrnCreateData *data, PGrnBuildStateData *bs)
{
	pgroonga_build_copy_source_execute(data, bs, true, NULL);
}

#ifdef PGRN_SUPPORT_PARALLEL_INDEX_BUILD
/*
 * Parallel source copy related feature is unstable. This
 * implementation was slower than serial source copy with some
 * tests.
 *
 * The bottle neck of source copy wasn't serial data read from
 * PostgreSQL and data write to Groonga. The bottle neck of source
 * copy was casting source data to reference values. In casting to
 * reference values, we need to add a record to a Groonga table. It
 * needs a lock. It may be a slow cause. Or grn_obj_cast() related
 * code may be a slow cause.
 *
 * So we disable this by default. We may revisit this when we think
 * that this is useful.
 */

static const char *PGroongaLibraryName = "pgroonga";

typedef struct PGrnParallelBuildLocalData
{
	Relation heap;
	Relation index;
	ParallelTableScanDesc pscan;
} PGrnParallelBuildLocalData;

typedef struct PGrnParallelBuildSharedData
{
	/* Immutable data */
	Oid heapOid;
	Oid indexOid;
	grn_id sourcesTableID;
	grn_id sourcesCtidColumnID;
	bool isConcurrent;
	bool needMaxRecordSizeUpdate;
	bool isBulkInsert;
	uint64 queryID;

	/* For synchronization */
	slock_t mutex;
	ConditionVariable conditionVariable;

	/* Mutable data */
	int nFinishedWorkers;
	uint32_t maxRecordSize;
	double nProcessedHeapTuples;
	double nIndexedTuples;
	bool haveBrokenHotChain;
} PGrnParallelBuildSharedData;

#	define PGRN_PARALLEL_BUILD_KEY_PSCAN UINT64CONST(0xA000000000000001)
#	define PGRN_PARALLEL_BUILD_KEY_SHARED_DATA UINT64CONST(0xA000000000000002)
#	define PGRN_PARALLEL_BUILD_KEY_DEBUG_QUERY_STRING                         \
		UINT64CONST(0xA000000000000003)
#	define PGRN_PARALLEL_BUILD_KEY_BUFFER_USAGES                              \
		UINT64CONST(0xA000000000000004)
#	define PGRN_PARALLEL_BUILD_KEY_WAL_USAGES UINT64CONST(0xA000000000000005)

static void
pgroonga_build_copy_source_worker(PGrnParallelBuildLocalData *localData,
								  PGrnParallelBuildSharedData *sharedData,
								  PGrnBuildStateData *bs)
{
	PGrnCreateData createData;
	bool progress;
	TableScanDesc scan;

	createData.heap = localData->heap;
	createData.index = localData->index;
	createData.indexInfo = BuildIndexInfo(localData->index);
	createData.indexInfo->ii_Concurrent = sharedData->isConcurrent;
	progress = (ParallelWorkerNumber == -1);
	scan = pgrn_table_beginscan_parallel(
		localData->heap, localData->pscan, SO_NONE);
	pgroonga_build_copy_source_execute(&createData, bs, progress, scan);

	SpinLockAcquire(&(sharedData->mutex));
	sharedData->nFinishedWorkers++;
	if (sharedData->needMaxRecordSizeUpdate &&
		bs->maxRecordSize > sharedData->maxRecordSize)
		sharedData->maxRecordSize = bs->maxRecordSize;
	sharedData->nProcessedHeapTuples += bs->nProcessedHeapTuples;
	sharedData->nIndexedTuples += bs->nIndexedTuples;
	if (createData.indexInfo->ii_BrokenHotChain)
		sharedData->haveBrokenHotChain = true;
	SpinLockRelease(&(sharedData->mutex));

	ConditionVariableSignal(&(sharedData->conditionVariable));
}

extern PGDLLEXPORT void
pgroonga_build_copy_source_parallel_main(dsm_segment *seg, shm_toc *toc);

void
pgroonga_build_copy_source_parallel_main(dsm_segment *seg, shm_toc *toc)
{
	ParallelTableScanDesc pscan;
	PGrnParallelBuildSharedData *sharedData;
	PGrnParallelBuildLocalData localData;
	PGrnBuildStateData bs;
	LOCKMODE heapLockMode;
	LOCKMODE indexLockMode;

	/* MyDatabaseId isn't initialized yet when _PG_Init() is called. */
	PGrnEnsureDatabase();

	debug_query_string =
		shm_toc_lookup(toc, PGRN_PARALLEL_BUILD_KEY_DEBUG_QUERY_STRING, true);
	pgstat_report_activity(STATE_RUNNING, debug_query_string);

	pscan = shm_toc_lookup(toc, PGRN_PARALLEL_BUILD_KEY_PSCAN, false);
	sharedData =
		shm_toc_lookup(toc, PGRN_PARALLEL_BUILD_KEY_SHARED_DATA, false);

	if (sharedData->isConcurrent)
	{
		heapLockMode = ShareUpdateExclusiveLock;
		indexLockMode = RowExclusiveLock;
	}
	else
	{
		heapLockMode = ShareLock;
		indexLockMode = AccessExclusiveLock;
	}

	pgstat_report_query_id(sharedData->queryID, false);

	InstrStartParallelQuery();

	localData.heap = table_open(sharedData->heapOid, heapLockMode);
	localData.index = index_open(sharedData->indexOid, indexLockMode);
	localData.pscan = pscan;
	bs.memoryContext =
		AllocSetContextCreate(CurrentMemoryContext,
							  "PGroonga parallel index build temporay context",
							  ALLOCSET_DEFAULT_SIZES);
	bs.sourcesTable = grn_ctx_at(ctx, sharedData->sourcesTableID);
	if (sharedData->sourcesCtidColumnID == GRN_ID_NIL)
		bs.sourcesCtidColumn = NULL;
	else
		bs.sourcesCtidColumn = grn_ctx_at(ctx, sharedData->sourcesCtidColumnID);
	bs.needMaxRecordSizeUpdate = sharedData->needMaxRecordSizeUpdate;
	bs.maxRecordSize = 0;
	bs.nProcessedHeapTuples = 0.0;
	bs.nIndexedTuples = 0.0;
	bs.isBulkInsert = sharedData->isBulkInsert;
	bs.bulkInsertWALData = NULL;
	bs.walRoleKeep = grn_ctx_get_wal_role(ctx);
	pgroonga_build_copy_source_worker(&localData, sharedData, &bs);
	MemoryContextDelete(bs.memoryContext);

	{
		BufferUsage *bufferUsages =
			shm_toc_lookup(toc, PGRN_PARALLEL_BUILD_KEY_BUFFER_USAGES, false);
		WalUsage *walUsages =
			shm_toc_lookup(toc, PGRN_PARALLEL_BUILD_KEY_WAL_USAGES, false);
		InstrEndParallelQuery(&(bufferUsages[ParallelWorkerNumber]),
							  &(walUsages[ParallelWorkerNumber]));
	}

	index_close(localData.index, indexLockMode);
	table_close(localData.heap, heapLockMode);
}

static void
pgroonga_build_copy_source_parallel(PGrnCreateData *data,
									PGrnBuildStateData *bs)
{
	ParallelContext *pcxt;
	Snapshot snapshot;
	ParallelTableScanDesc pscan;
	Size pscanSize;
	PGrnParallelBuildSharedData *sharedData;
	Size sharedDataSize;
	Size debugQueryStringSize = 0;
	BufferUsage *bufferUsages;
	Size bufferUsagesSize;
	WalUsage *walUsages;
	Size walUsagesSize;

	EnterParallelMode();
	pcxt = CreateParallelContext(PGroongaLibraryName,
								 "pgroonga_build_copy_source_parallel_main",
								 data->indexInfo->ii_ParallelWorkers);

	/*
	 * This is done automatically when we use table_index_build_scan()
	 * with scan=NULL in serial build. But we need to do this manually
	 * for parrallel build.
	 */
	if (data->indexInfo->ii_Concurrent)
		snapshot = RegisterSnapshot(GetTransactionSnapshot());
	else
		snapshot = SnapshotAny;

	pscanSize = table_parallelscan_estimate(data->heap, snapshot);
	shm_toc_estimate_chunk(&(pcxt->estimator), pscanSize);
	shm_toc_estimate_keys(&(pcxt->estimator), 1);

	sharedDataSize = BUFFERALIGN(sizeof(PGrnParallelBuildSharedData));
	shm_toc_estimate_chunk(&(pcxt->estimator), sharedDataSize);
	shm_toc_estimate_keys(&(pcxt->estimator), 1);

	if (debug_query_string)
	{
		debugQueryStringSize = strlen(debug_query_string) + 1;
		shm_toc_estimate_chunk(&pcxt->estimator, debugQueryStringSize);
		shm_toc_estimate_keys(&pcxt->estimator, 1);
	}

	bufferUsagesSize = mul_size(sizeof(BufferUsage), pcxt->nworkers);
	shm_toc_estimate_chunk(&(pcxt->estimator), bufferUsagesSize);
	shm_toc_estimate_keys(&(pcxt->estimator), 1);

	walUsagesSize = mul_size(sizeof(WalUsage), pcxt->nworkers);
	shm_toc_estimate_chunk(&(pcxt->estimator), walUsagesSize);
	shm_toc_estimate_keys(&(pcxt->estimator), 1);

	InitializeParallelDSM(pcxt);
	if (!pcxt->seg)
	{
		if (IsMVCCSnapshot(snapshot))
			UnregisterSnapshot(snapshot);
		DestroyParallelContext(pcxt);
		ExitParallelMode();

		/* Fallback to serial build. */
		pgroonga_build_copy_source_serial(data, bs);
		return;
	}

	pscan = shm_toc_allocate(pcxt->toc, pscanSize);
	table_parallelscan_initialize(data->heap, pscan, snapshot);
	shm_toc_insert(pcxt->toc, PGRN_PARALLEL_BUILD_KEY_PSCAN, pscan);

	sharedData = shm_toc_allocate(pcxt->toc, sharedDataSize);
	sharedData->heapOid = RelationGetRelid(data->heap);
	sharedData->indexOid = RelationGetRelid(data->index);
	sharedData->sourcesTableID = grn_obj_id(ctx, bs->sourcesTable);
	if (bs->sourcesCtidColumn)
		sharedData->sourcesCtidColumnID =
			grn_obj_id(ctx, bs->sourcesCtidColumn);
	else
		sharedData->sourcesCtidColumnID = GRN_ID_NIL;
	sharedData->isConcurrent = data->indexInfo->ii_Concurrent;
	sharedData->needMaxRecordSizeUpdate = bs->needMaxRecordSizeUpdate;
	sharedData->isBulkInsert = bs->isBulkInsert;
	sharedData->queryID = pgstat_get_my_query_id();
	sharedData->nFinishedWorkers = 0;
	sharedData->maxRecordSize = bs->maxRecordSize;
	sharedData->nProcessedHeapTuples = 0.0;
	sharedData->nIndexedTuples = 0.0;
	sharedData->haveBrokenHotChain = false;
	SpinLockInit(&(sharedData->mutex));
	ConditionVariableInit(&(sharedData->conditionVariable));
	shm_toc_insert(pcxt->toc, PGRN_PARALLEL_BUILD_KEY_SHARED_DATA, sharedData);

	if (debugQueryStringSize > 0)
	{
		char *sharedDebugQueryString =
			shm_toc_allocate(pcxt->toc, debugQueryStringSize);
		memcpy(
			sharedDebugQueryString, debug_query_string, debugQueryStringSize);
		shm_toc_insert(pcxt->toc,
					   PGRN_PARALLEL_BUILD_KEY_DEBUG_QUERY_STRING,
					   sharedDebugQueryString);
	}

	bufferUsages = shm_toc_allocate(pcxt->toc, bufferUsagesSize);
	shm_toc_insert(
		pcxt->toc, PGRN_PARALLEL_BUILD_KEY_BUFFER_USAGES, bufferUsages);

	walUsages = shm_toc_allocate(pcxt->toc, walUsagesSize);
	shm_toc_insert(pcxt->toc, PGRN_PARALLEL_BUILD_KEY_WAL_USAGES, walUsages);

	LaunchParallelWorkers(pcxt);
	if (pcxt->nworkers_launched == 0)
	{
		WaitForParallelWorkersToFinish(pcxt);
		if (IsMVCCSnapshot(snapshot))
			UnregisterSnapshot(snapshot);
		DestroyParallelContext(pcxt);
		ExitParallelMode();

		/* Fallback to serial build. */
		pgroonga_build_copy_source_serial(data, bs);
		return;
	}

	/* Copy source in the leader process too. */
	{
		PGrnParallelBuildLocalData localData;
		PGrnBuildStateData localBS;

		localData.heap = data->heap;
		localData.index = data->index;
		localData.pscan = pscan;
		localBS.memoryContext = bs->memoryContext;
		localBS.sourcesTable = bs->sourcesTable;
		localBS.sourcesCtidColumn = bs->sourcesCtidColumn;
		localBS.needMaxRecordSizeUpdate = bs->needMaxRecordSizeUpdate;
		localBS.maxRecordSize = 0;
		localBS.nProcessedHeapTuples = 0.0;
		localBS.nIndexedTuples = 0.0;
		localBS.isBulkInsert = bs->isBulkInsert;
		localBS.bulkInsertWALData = NULL;
		localBS.walRoleKeep = bs->walRoleKeep;
		pgroonga_build_copy_source_worker(&localData, sharedData, &localBS);
	}

	WaitForParallelWorkersToAttach(pcxt);

	while (true)
	{
		bool finished;
		SpinLockAcquire(&(sharedData->mutex));
		finished =
			(sharedData->nFinishedWorkers == pcxt->nworkers_launched + 1);
		SpinLockRelease(&(sharedData->mutex));
		if (finished)
			break;
		ConditionVariableSleep(&(sharedData->conditionVariable),
							   WAIT_EVENT_PARALLEL_CREATE_INDEX_SCAN);
	}
	ConditionVariableCancelSleep();

	if (bs->needMaxRecordSizeUpdate &&
		sharedData->maxRecordSize > bs->maxRecordSize)
		bs->maxRecordSize = sharedData->maxRecordSize;
	bs->nProcessedHeapTuples = sharedData->nProcessedHeapTuples;
	bs->nIndexedTuples = sharedData->nIndexedTuples;
	if (sharedData->haveBrokenHotChain)
		data->indexInfo->ii_BrokenHotChain = true;

	WaitForParallelWorkersToFinish(pcxt);
	{
		int i;
		for (i = 0; i < pcxt->nworkers_launched; i++)
			InstrAccumParallelQuery(&(bufferUsages[i]), &(walUsages[i]));
	}
	if (IsMVCCSnapshot(snapshot))
		UnregisterSnapshot(snapshot);
	DestroyParallelContext(pcxt);
	ExitParallelMode();
}
#endif

typedef struct PGrnProgressState
{
	grn_progress_index_phase phase;
} PGrnProgressState;

static void
PGrnUpdateProgressCreateIndexSubphase(grn_progress_index_phase phase)
{
	switch (phase)
	{
	case GRN_PROGRESS_INDEX_LOAD:
		pgstat_progress_update_param(PROGRESS_CREATEIDX_SUBPHASE,
									 PROGRESS_PGROONGA_PHASE_INDEX_LOAD);
		break;
	case GRN_PROGRESS_INDEX_COMMIT:
		pgstat_progress_update_param(PROGRESS_CREATEIDX_SUBPHASE,
									 PROGRESS_PGROONGA_PHASE_INDEX_COMMIT);
		break;
	case GRN_PROGRESS_INDEX_DONE:
		pgstat_progress_update_param(PROGRESS_CREATEIDX_SUBPHASE,
									 PROGRESS_PGROONGA_PHASE_DONE);
		break;
#if GRN_VERSION_OR_LATER(15, 2, 1)
	case GRN_PROGRESS_INDEX_VECTORIZE:
		pgstat_progress_update_param(PROGRESS_CREATEIDX_SUBPHASE,
									 PROGRESS_PGROONGA_PHASE_INDEX_VECTORIZE);
		break;
	case GRN_PROGRESS_INDEX_CLUSTER:
		pgstat_progress_update_param(PROGRESS_CREATEIDX_SUBPHASE,
									 PROGRESS_PGROONGA_PHASE_INDEX_CLUSTER);
		break;
#endif
	default:
		break;
	}
}

static void
PGrnProgressCallback(grn_ctx *ctx, grn_progress *progress, void *user_data)
{
	PGrnProgressState *state = user_data;
	grn_progress_index_phase phase;

	if (grn_progress_get_type(ctx, progress) != GRN_PROGRESS_INDEX)
	{
		return;
	}

	phase = grn_progress_index_get_phase(ctx, progress);
	switch (phase)
	{
	case GRN_PROGRESS_INDEX_LOAD:
#if GRN_VERSION_OR_LATER(15, 2, 1)
	case GRN_PROGRESS_INDEX_VECTORIZE:
	case GRN_PROGRESS_INDEX_CLUSTER:
#endif
		if (phase != state->phase)
		{
			uint32_t n_target_records =
				grn_progress_index_get_n_target_records(ctx, progress);
			PGrnUpdateProgressCreateIndexSubphase(phase);
			pgstat_progress_update_param(PROGRESS_CREATEIDX_TUPLES_TOTAL,
										 n_target_records);
		}
		{
			uint32_t n_processed_records =
				grn_progress_index_get_n_processed_records(ctx, progress);
			pgstat_progress_update_param(PROGRESS_CREATEIDX_TUPLES_DONE,
										 n_processed_records);
		}
		break;
	case GRN_PROGRESS_INDEX_COMMIT:
		if (phase != state->phase)
		{
			uint32_t n_target_terms =
				grn_progress_index_get_n_target_terms(ctx, progress);
			PGrnUpdateProgressCreateIndexSubphase(phase);
			pgstat_progress_update_param(PROGRESS_CREATEIDX_TUPLES_TOTAL,
										 n_target_terms);
		}
		{
			uint32_t n_processed_terms =
				grn_progress_index_get_n_processed_terms(ctx, progress);
			pgstat_progress_update_param(PROGRESS_CREATEIDX_TUPLES_DONE,
										 n_processed_terms);
		}
		break;
	case GRN_PROGRESS_INDEX_DONE:
		PGrnUpdateProgressCreateIndexSubphase(phase);
		break;
	default:
		break;
	}
	state->phase = phase;
}

static IndexBuildResult *
pgroonga_build(Relation heap, Relation index, IndexInfo *indexInfo)
{
	const char *tag = "[build]";
	IndexBuildResult *result;
	PGrnCreateData data;
	PGrnBuildStateData bs;
	grn_obj supplementaryTables;
	grn_obj lexicons;
	int32_t nWorkersKeep = grn_ctx_get_n_workers(ctx);

	PGRN_TRACE_LOG_ENTER();

	if (!PGrnIsWritable())
	{
		ereport(ERROR,
				(errcode(ERRCODE_E_R_E_MODIFYING_SQL_DATA_NOT_PERMITTED),
				 errmsg("pgroonga: %s "
						"can't create an index "
						"while pgroonga.writable is false",
						tag)));
	}

	if (indexInfo->ii_Unique)
		PGrnCheckRC(GRN_FUNCTION_NOT_IMPLEMENTED,
					"%s unique index isn't supported",
					tag);

	PGrnEnsureLatestDB();

	PGrnAutoCloseUseIndex(index);

	if (index->rd_rel->relpersistence == RELPERSISTENCE_UNLOGGED)
	{
		/* We don't need this but this is required for UNLOGGED table.
		 * index_build() calls smgrexists(indexRelation->rd_smgr,
		 * INIT_FORKNUM) without indexRelation->rd_smgr != NULL check. */
#if PG_VERSION_NUM >= 150000
		smgrcreate(RelationGetSmgr(index), INIT_FORKNUM, false);
#else
		RelationOpenSmgr(index);
		smgrcreate(index->rd_smgr, INIT_FORKNUM, false);
#endif
	}

	data.heap = heap;
	data.index = index;
	data.indexInfo = indexInfo;
	data.sourcesTable = NULL;

	bs.sourcesTable = NULL;
	bs.sourcesCtidColumn = NULL;
	bs.nProcessedHeapTuples = 0.0;
	bs.nIndexedTuples = 0.0;
	bs.needMaxRecordSizeUpdate = PGrnNeedMaxRecordSizeUpdate(index);
	bs.maxRecordSize = 0;
	bs.memoryContext =
		AllocSetContextCreate(CurrentMemoryContext,
							  "PGroonga index build temporay context",
							  ALLOCSET_DEFAULT_SIZES);
	bs.bulkInsertWALData = NULL;

	bs.isBulkInsert =
		PGrnWALResourceManagerIsOnlyEnabled() && !PGrnIsJSONBIndex(index);
	bs.walRoleKeep = grn_ctx_get_wal_role(ctx);

	GRN_PTR_INIT(&supplementaryTables, GRN_OBJ_VECTOR, GRN_ID_NIL);
	GRN_PTR_INIT(&lexicons, GRN_OBJ_VECTOR, GRN_ID_NIL);
	PG_TRY();
	{
		PGrnProgressState state = {0};

		state.phase = GRN_PROGRESS_INDEX_INVALID;
		data.supplementaryTables = &supplementaryTables;
		data.lexicons = &lexicons;
		data.desc = RelationGetDescr(index);
		data.relNumber = PGRN_RELATION_GET_LOCATOR_NUMBER(index);
		PGrnCreate(&data);
		bs.sourcesTable = data.sourcesTable;
		bs.sourcesCtidColumn = data.sourcesCtidColumn;
		pgstat_progress_update_param(PROGRESS_CREATEIDX_SUBPHASE,
									 PROGRESS_PGROONGA_PHASE_IMPORT);

#ifdef PGRN_SUPPORT_PARALLEL_INDEX_BUILD
		if (indexInfo->ii_ParallelWorkers > 0 && PGrnEnableParallelBuildCopy)
			pgroonga_build_copy_source_parallel(&data, &bs);
		else
			pgroonga_build_copy_source_serial(&data, &bs);
#else
		pgroonga_build_copy_source_serial(&data, &bs);
#endif

		if (indexInfo->ii_ParallelWorkers > 0)
		{
			/* All of workers and leader compute in In PostgreSQL but
			 * only workers compute in Groonga. So we add +1 here. */
			grn_ctx_set_n_workers(ctx, indexInfo->ii_ParallelWorkers + 1);
		}
		grn_ctx_set_progress_callback(ctx, PGrnProgressCallback, &state);
		PGrnSetSources(index, bs.sourcesTable);
		grn_ctx_set_progress_callback(ctx, NULL, NULL);
		if (indexInfo->ii_ParallelWorkers > 0)
			grn_ctx_set_n_workers(ctx, nWorkersKeep);

		PGrnCreateSourcesTableFinish(&data);
	}
	PG_CATCH();
	{
		size_t i, n;

		/* Ensure restoring the number of workers on error. */
		if (indexInfo->ii_ParallelWorkers > 0)
			grn_ctx_set_n_workers(ctx, nWorkersKeep);

		/* Ensure restoring WAL role on error. */
		if (bs.walRoleKeep != GRN_WAL_ROLE_NONE)
			grn_ctx_set_wal_role(ctx, bs.walRoleKeep);

		if (bs.isBulkInsert)
			PGrnWALAbort(bs.bulkInsertWALData);

		n = GRN_BULK_VSIZE(&lexicons) / sizeof(grn_obj *);
		for (i = 0; i < n; i++)
		{
			grn_obj *lexicon;
			lexicon = GRN_PTR_VALUE_AT(&lexicons, i);
			grn_obj_remove(ctx, lexicon);
		}
		GRN_OBJ_FIN(ctx, &lexicons);

		n = GRN_BULK_VSIZE(&supplementaryTables) / sizeof(grn_obj *);
		for (i = 0; i < n; i++)
		{
			grn_obj *supplementaryTable;
			supplementaryTable = GRN_PTR_VALUE_AT(&supplementaryTables, i);
			grn_obj_remove(ctx, supplementaryTable);
		}
		GRN_OBJ_FIN(ctx, &supplementaryTables);

		if (data.sourcesTable)
			grn_obj_remove(ctx, data.sourcesTable);

		grn_ctx_set_progress_callback(ctx, NULL, NULL);

		PG_RE_THROW();
	}
	PG_END_TRY();
	GRN_OBJ_FIN(ctx, &lexicons);
	GRN_OBJ_FIN(ctx, &supplementaryTables);

	result = (IndexBuildResult *) palloc(sizeof(IndexBuildResult));
	result->heap_tuples = bs.nProcessedHeapTuples;
	result->index_tuples = bs.nIndexedTuples;

	MemoryContextDelete(bs.memoryContext);

	if (bs.needMaxRecordSizeUpdate)
	{
		PGrnUpdateMaxRecordSize(index, bs.maxRecordSize);
	}

	PGRN_TRACE_LOG_EXIT();

	return result;
}

static void
pgroonga_buildempty(Relation index)
{
	const char *tag = "[build-empty]";
	PGrnCreateData data;
	grn_obj supplementaryTables;
	grn_obj lexicons;

	PGRN_TRACE_LOG_ENTER();

	if (!PGrnIsWritable())
	{
		ereport(ERROR,
				(errcode(ERRCODE_E_R_E_MODIFYING_SQL_DATA_NOT_PERMITTED),
				 errmsg("pgroonga: %s "
						"can't create an empty index "
						"while pgroonga.writable is false",
						tag)));
	}

	PGrnEnsureLatestDB();

	PGrnAutoCloseUseIndex(index);

	GRN_PTR_INIT(&supplementaryTables, GRN_OBJ_VECTOR, GRN_ID_NIL);
	GRN_PTR_INIT(&lexicons, GRN_OBJ_VECTOR, GRN_ID_NIL);
	PG_TRY();
	{
		data.heap = NULL;
		data.index = index;
		data.indexInfo = NULL;
		data.sourcesTable = NULL;
		data.sourcesCtidColumn = NULL;
		data.supplementaryTables = &supplementaryTables;
		data.lexicons = &lexicons;
		data.desc = RelationGetDescr(index);
		data.relNumber = PGRN_RELATION_GET_LOCATOR_NUMBER(index);
		PGrnCreate(&data);
		PGrnSetSources(index, data.sourcesTable);
		PGrnCreateSourcesTableFinish(&data);
	}
	PG_CATCH();
	{
		size_t i, n;

		n = GRN_BULK_VSIZE(&lexicons) / sizeof(grn_obj *);
		for (i = 0; i < n; i++)
		{
			grn_obj *lexicon;
			lexicon = GRN_PTR_VALUE_AT(&lexicons, i);
			grn_obj_remove(ctx, lexicon);
		}
		GRN_OBJ_FIN(ctx, &lexicons);

		n = GRN_BULK_VSIZE(&supplementaryTables) / sizeof(grn_obj *);
		for (i = 0; i < n; i++)
		{
			grn_obj *supplementaryTable;
			supplementaryTable = GRN_PTR_VALUE_AT(&supplementaryTables, i);
			grn_obj_remove(ctx, supplementaryTable);
		}
		GRN_OBJ_FIN(ctx, &supplementaryTables);

		if (data.sourcesTable)
			grn_obj_remove(ctx, data.sourcesTable);

		PG_RE_THROW();
	}
	PG_END_TRY();
	GRN_OBJ_FIN(ctx, &lexicons);
	GRN_OBJ_FIN(ctx, &supplementaryTables);

	PGRN_TRACE_LOG_EXIT();
}

static IndexBulkDeleteResult *
PGrnBulkDeleteResult(IndexVacuumInfo *info, grn_obj *sourcesTable)
{
	IndexBulkDeleteResult *stats;

	stats = (IndexBulkDeleteResult *) palloc0(sizeof(IndexBulkDeleteResult));
	stats->num_pages = (BlockNumber) 1; /* TODO: sizeof index / BLCKSZ */

	/* table might be NULL if index is corrupted */
	if (sourcesTable)
		stats->num_index_tuples = grn_table_size(ctx, sourcesTable);
	else
		stats->num_index_tuples = 0;

	return stats;
}

static IndexBulkDeleteResult *
pgroonga_bulkdelete(IndexVacuumInfo *info,
					IndexBulkDeleteResult *stats,
					IndexBulkDeleteCallback callback,
					void *callbackState)
{
	const char *tag = "[bulk-delete]";
	Relation index = info->index;
	grn_obj *sourcesTable;
	grn_table_cursor *cursor;
	double nRemovedTuples;

	PGRN_TRACE_LOG_ENTER();

	if (!PGrnIsWritable())
	{
		ereport(ERROR,
				(errcode(ERRCODE_E_R_E_MODIFYING_SQL_DATA_NOT_PERMITTED),
				 errmsg("pgroonga: %s "
						"can't delete bulk records "
						"while pgroonga.writable is false",
						tag)));
	}

	PGrnEnsureLatestDB();

	sourcesTable = PGrnLookupSourcesTable(index, WARNING);

	if (!stats)
		stats = PGrnBulkDeleteResult(info, sourcesTable);

	if (!sourcesTable || !callback)
	{
		PGRN_TRACE_LOG_EXIT();
		return stats;
	}

	nRemovedTuples = 0;

	cursor =
		grn_table_cursor_open(ctx, sourcesTable, NULL, 0, NULL, 0, 0, -1, 0);
	PGrnCheck("%s failed to open cursor", tag);

	PG_TRY();
	{
		grn_id id;
		grn_obj *sourcesCtidColumn = NULL;
		PGrnJSONBBulkDeleteData jsonbData;

		if (sourcesTable->header.type == GRN_TABLE_NO_KEY)
		{
			sourcesCtidColumn = PGrnLookupSourcesCtidColumn(index, ERROR);
		}

		jsonbData.index = index;
		jsonbData.sourcesTable = sourcesTable;
		PGrnJSONBBulkDeleteInit(&jsonbData);

		while ((id = grn_table_cursor_next(ctx, cursor)) != GRN_ID_NIL)
		{
			uint64_t packedCtid;
			ItemPointerData ctid;

			CHECK_FOR_INTERRUPTS();

			if (sourcesCtidColumn)
			{
				GRN_BULK_REWIND(&(buffers->ctid));
				grn_obj_get_value(ctx, sourcesCtidColumn, id, &(buffers->ctid));
				if (GRN_BULK_VSIZE(&(buffers->ctid)) == 0)
				{
					GRN_LOG(ctx,
							GRN_LOG_DEBUG,
							"pgroonga: %s[nonexistent] <%s>(%u): <%u>",
							tag,
							index->rd_rel->relname.data,
							index->rd_id,
							id);
					continue;
				}
				packedCtid = GRN_UINT64_VALUE(&(buffers->ctid));
			}
			else
			{
				void *key;
				int keySize;
				keySize = grn_table_cursor_get_key(ctx, cursor, &key);
				if (keySize == 0)
				{
					GRN_LOG(ctx,
							GRN_LOG_DEBUG,
							"pgroonga: %s[nonexistent] <%s>(%u): <%u>",
							tag,
							index->rd_rel->relname.data,
							index->rd_id,
							id);
					continue;
				}
				packedCtid = *((uint64_t *) key);
			}
			ctid = PGrnCtidUnpack(packedCtid);
			if (callback(&ctid, callbackState))
			{
				GRN_LOG(ctx,
						GRN_LOG_DEBUG,
						"pgroonga: %s <%s>(%u): <%u>: <(%u,%u),%u>(%" PRIu64
						")",
						tag,
						index->rd_rel->relname.data,
						index->rd_id,
						id,
						ctid.ip_blkid.bi_hi,
						ctid.ip_blkid.bi_lo,
						ctid.ip_posid,
						packedCtid);

				jsonbData.id = id;
				PGrnJSONBBulkDeleteRecord(&jsonbData);

				grn_table_cursor_delete(ctx, cursor);
				PGrnWALDelete(index,
							  sourcesTable,
							  (const char *) &packedCtid,
							  sizeof(uint64_t));

				nRemovedTuples += 1;
			}
		}

		PGrnJSONBBulkDeleteFin(&jsonbData);

		grn_table_cursor_close(ctx, cursor);
	}
	PG_CATCH();
	{
		grn_table_cursor_close(ctx, cursor);
		PG_RE_THROW();
	}
	PG_END_TRY();

	stats->tuples_removed = nRemovedTuples;

	PGRN_TRACE_LOG_EXIT();

	return stats;
}

static void
PGrnRemoveUnusedTable(Relation index, Oid relationFileNodeID)
{
	unsigned int i;

	for (i = 0; true; i++)
	{
		char tableName[GRN_TABLE_MAX_KEY_SIZE];
		grn_obj *lexicon;

		snprintf(tableName,
				 sizeof(tableName),
				 PGrnLexiconNameFormat,
				 relationFileNodeID,
				 i);
		lexicon = grn_ctx_get(ctx, tableName, -1);
		if (!lexicon)
			break;

		PGrnRemoveColumns(index, lexicon);
	}

	{
		char tableName[GRN_TABLE_MAX_KEY_SIZE];
		snprintf(tableName,
				 sizeof(tableName),
				 PGrnSourcesTableNameFormat,
				 relationFileNodeID);
		PGrnRemoveObjectForce(index, tableName);
		PGrnAliasDeleteRaw(relationFileNodeID);
		PGrnIndexStatusDeleteRaw(relationFileNodeID);
	}

	for (i = 0; true; i++)
	{
		char tableName[GRN_TABLE_MAX_KEY_SIZE];
		grn_obj *lexicon;

		snprintf(tableName,
				 sizeof(tableName),
				 PGrnLexiconNameFormat,
				 relationFileNodeID,
				 i);
		lexicon = grn_ctx_get(ctx, tableName, -1);
		if (!lexicon)
			break;

		PGrnRemoveObjectForce(index, tableName);
	}

	PGrnJSONBRemoveUnusedTables(relationFileNodeID);
}

void
PGrnRemoveUnusedTables(void)
{
	grn_table_cursor *cursor;
	const char *min = PGrnSourcesTableNamePrefix;
	grn_obj targetRelationFileNodIDs;

	PGRN_TRACE_LOG_ENTER();

	if (!PGrnIsWritable())
	{
		PGRN_TRACE_LOG_EXIT();
		return;
	}

	/* We can't detect alive indexes in prepared transactions. */
	if (PGrnPGHavePreparedTransaction())
	{
		PGRN_TRACE_LOG_EXIT();
		return;
	}

	/* This is needed for preventing removing already removed objects.
	 * Consider the following scenario:
	 *
	 * 1. Connection1: CREATE INDEX A
	 * 2. Connection1: Groonga object A` (ID: 1000) is created
	 * 3. Connection1: DROP INDEX A
	 * 4. Connection1: (Groonga object A` (ID: 1000) isn't removed yet.)
	 * 5. Connection2: VACUUM
	 * 6. Connection2: Remove Groonga object A` (ID: 1000)
	 * 7. Connection2: CREATE INDEX B
	 * 8. Connection2: Groonga object B` (ID: 1000, reused) is created
	 * 9. Connection2: DROP INDEX B
	 * 10. Connection1: VACUUM
	 * 11. Connection1: Groonga object (ID: 1000) is removed but its
	 *     Groonga object A` not Groonga object B` because Groonga
	 *     object A` is still open in connection1. This is the
	 *     problem.
	 */
	PGrnUnmapDB();

	if (processSharedData)
	{
		processSharedData->lastVacuumTimestamp = GetCurrentTimestamp();
	}

	GRN_UINT32_INIT(&targetRelationFileNodIDs, GRN_OBJ_VECTOR);
	cursor = grn_table_cursor_open(ctx,
								   grn_ctx_db(ctx),
								   min,
								   strlen(min),
								   NULL,
								   0,
								   0,
								   -1,
								   GRN_CURSOR_BY_KEY | GRN_CURSOR_PREFIX);
	while (grn_table_cursor_next(ctx, cursor) != GRN_ID_NIL)
	{
		void *key;
		char name[GRN_TABLE_MAX_KEY_SIZE];
		char *idEnd = NULL;
		int nameSize;
		Oid relationFileNodeID;

		nameSize = grn_table_cursor_get_key(ctx, cursor, &key);
		memcpy(name, key, nameSize);
		name[nameSize] = '\0';
		relationFileNodeID = strtol(name + strlen(min), &idEnd, 10);
		if (idEnd[0] == '.')
			continue;

		if (PGrnPGIsValidFileNodeID(relationFileNodeID))
			continue;

		GRN_UINT32_PUT(ctx, &targetRelationFileNodIDs, relationFileNodeID);
	}
	grn_table_cursor_close(ctx, cursor);

	{
		size_t i;
		size_t n = GRN_UINT32_VECTOR_SIZE(&targetRelationFileNodIDs);
		for (i = 0; i < n; i++)
		{
			Oid relationFileNodeID =
				GRN_UINT32_VALUE_AT(&targetRelationFileNodIDs, i);
			PGrnRemoveUnusedTable(NULL, relationFileNodeID);
		}
	}
	GRN_OBJ_FIN(ctx, &targetRelationFileNodIDs);

	PGRN_TRACE_LOG_EXIT();
}

static IndexBulkDeleteResult *
pgroonga_vacuumcleanup(IndexVacuumInfo *info, IndexBulkDeleteResult *stats)
{
	PGRN_TRACE_LOG_ENTER();

	if (!PGrnIsWritable())
	{
		PGRN_TRACE_LOG_EXIT();
		return stats;
	}

	if (!stats)
	{
		grn_obj *sourcesTable;
		sourcesTable = PGrnLookupSourcesTable(info->index, WARNING);
		stats = PGrnBulkDeleteResult(info, sourcesTable);
	}

	PGrnRemoveUnusedTables();

	PGRN_TRACE_LOG_EXIT();

	return stats;
}

static bool
pgroonga_canreturn(Relation index, int nthAttribute)
{
	bool can_return = true;
	Relation table = RelationIdGetRelation(index->rd_index->indrelid);
	TupleDesc table_desc = RelationGetDescr(table);
	TupleDesc desc = RelationGetDescr(index);
	unsigned int i;

	PGRN_TRACE_LOG_ENTER();

	for (i = 0; i < desc->natts; i++)
	{
		Form_pg_attribute attribute = TupleDescAttr(desc, i);

		bool is_nullable = true;
		unsigned int j;
		for (j = 0; j < table_desc->natts; j++)
		{
			Form_pg_attribute table_attribute = TupleDescAttr(table_desc, j);
			if (strcmp(NameStr(table_attribute->attname),
					   NameStr(attribute->attname)) != 0)
				continue;
			if (table_attribute->atttypid != attribute->atttypid)
				continue;
			is_nullable = !table_attribute->attnotnull;
			break;
		}
		if (is_nullable)
		{
			can_return = false;
			break;
		}

		if (PGrnAttributeIsJSONB(attribute->atttypid))
		{
			can_return = false;
			break;
		}

		if (PGrnIsForPrefixSearchIndex(index, i))
		{
			can_return = false;
			break;
		}
	}
	RelationClose(table);

	if (can_return)
	{
		can_return = PGrnIndexStatusGetMaxRecordSize(index) <
					 PGRN_INDEX_ONLY_SCAN_THRESHOLD_SIZE;
	}

	PGRN_TRACE_LOG_EXIT();

	return can_return;
}

static void
PGrnCostEstimateUpdateSelectivityOne(PlannerInfo *root,
									 IndexPath *path,
									 Relation index,
									 grn_obj *sourcesTable,
									 RestrictInfo *info)
{
	IndexOptInfo *indexInfo = path->indexinfo;
	OpExpr *expr;
	int strategy;
	Oid leftType;
	Oid rightType;
	Node *leftNode;
	Node *rightNode;
	Node *estimatedRightNode;
	Var *var;
	int nthAttribute = InvalidAttrNumber;
	Oid opFamily = InvalidOid;
	ScanKeyData key;
	PGrnSearchData data;

	if (!IsA(info->clause, OpExpr))
		return;

	expr = (OpExpr *) info->clause;

	leftNode = get_leftop(info->clause);
	rightNode = get_rightop(info->clause);

	if (!IsA(leftNode, Var))
		return;

	estimatedRightNode = estimate_expression_value(root, rightNode);
	if (!IsA(estimatedRightNode, Const))
		return;

	var = (Var *) leftNode;
	{
		int i;

		for (i = 0; i < indexInfo->ncolumns; i++)
		{
			if (indexInfo->indexkeys[i] == var->varattno)
			{
				nthAttribute = i + 1;
				break;
			}
		}
	}
	if (!AttributeNumberIsValid(nthAttribute))
		return;

	opFamily = index->rd_opfamily[nthAttribute - 1];
	get_op_opfamily_properties(
		expr->opno, opFamily, false, &strategy, &leftType, &rightType);

	key.sk_flags = 0;
	key.sk_attno = nthAttribute;
	key.sk_strategy = strategy;
	key.sk_argument = ((Const *) estimatedRightNode)->constvalue;
	PGrnSearchDataInit(&data, index, sourcesTable);
	PGrnSearchBuildCondition(index, &key, &data);
	{
		unsigned int estimatedSize;
		unsigned int nRecords;

		if (data.isEmptyCondition)
		{
			estimatedSize = 0;
		}
		else
		{
			estimatedSize = grn_expr_estimate_size(ctx, data.expression);
		}

		nRecords = grn_table_size(ctx, sourcesTable);
		if (estimatedSize > nRecords)
			estimatedSize = nRecords * 0.8;
		if (estimatedSize == nRecords)
		{
			/* TODO: estimatedSize == nRecords means
			 * estimation isn't supported in Groonga. We should
			 * support it in Groonga. */
			info->norm_selec = 0.01;
		}
		else
		{
			info->norm_selec = (double) estimatedSize / (double) nRecords;
			/* path->path.rows = (double) estimatedSize; */
		}
	}
	PGrnSearchDataFree(&data);
}

static void
PGrnCostEstimateUpdateSelectivity(Relation index,
								  PlannerInfo *root,
								  IndexPath *path)
{
	grn_obj *sourcesTable;
	List *quals;
	ListCell *cell;

	PGrnWALApply(index);
	sourcesTable = PGrnLookupSourcesTable(index, ERROR);

	quals = get_quals_from_indexclauses(path->indexclauses);
	foreach (cell, quals)
	{
		Node *clause = (Node *) lfirst(cell);
		RestrictInfo *info;

		if (!IsA(clause, RestrictInfo))
			continue;

		info = (RestrictInfo *) clause;
		PGrnCostEstimateUpdateSelectivityOne(
			root, path, index, sourcesTable, info);
	}
}

static void
pgroonga_costestimate_internal(Relation index,
							   PlannerInfo *root,
							   IndexPath *path,
							   double loopCount,
							   Cost *indexStartupCost,
							   Cost *indexTotalCost,
							   Selectivity *indexSelectivity,
							   double *indexCorrelation,
							   double *indexPages)
{
	List *indexQuals;
	List *quals;
	PGrnCostEstimateUpdateSelectivity(index, root, path);
	indexQuals = get_quals_from_indexclauses(path->indexclauses);
	quals = add_predicate_to_index_quals(path->indexinfo, indexQuals);
	*indexSelectivity = clauselist_selectivity(
		root, quals, path->indexinfo->rel->relid, JOIN_INNER, NULL);

	*indexStartupCost = 0.0; /* TODO */
	*indexTotalCost = 0.0;   /* TODO */
	*indexCorrelation = 0.0;
	*indexPages = 0.0; /* TODO */
}

static void
pgroonga_costestimate(PlannerInfo *root,
					  IndexPath *path,
					  double loopCount,
					  Cost *indexStartupCost,
					  Cost *indexTotalCost,
					  Selectivity *indexSelectivity,
					  double *indexCorrelation,
					  double *indexPages)
{
	IndexOptInfo *indexInfo = path->indexinfo;
	Relation index = RelationIdGetRelation(indexInfo->indexoid);

	PGRN_TRACE_LOG_ENTER();

	PGrnEnsureLatestDB();

	*indexSelectivity = 0.0;
	*indexStartupCost = 0.0;
	*indexTotalCost = 0.0;
	*indexCorrelation = 0.0;
	*indexPages = 0.0;

	PGRN_RLS_ENABLED_IF(PGrnCheckRLSEnabled(index->rd_index->indrelid));
	{
		pgroonga_costestimate_internal(index,
									   root,
									   path,
									   loopCount,
									   indexStartupCost,
									   indexTotalCost,
									   indexSelectivity,
									   indexCorrelation,
									   indexPages);
	}
	PGRN_RLS_ENABLED_ELSE();
	{
		pgroonga_costestimate_internal(index,
									   root,
									   path,
									   loopCount,
									   indexStartupCost,
									   indexTotalCost,
									   indexSelectivity,
									   indexCorrelation,
									   indexPages);
	}
	PGRN_RLS_ENABLED_END();
	RelationClose(index);

	PGRN_TRACE_LOG_EXIT();
}

static char *
pgroonga_buildphrasename(int64 phrase)
{
	switch (phrase)
	{
	case PROGRESS_CREATEIDX_SUBPHASE_INITIALIZE:
		return "initializing";
	case PROGRESS_PGROONGA_PHASE_IMPORT:
		return "importing";
	case PROGRESS_PGROONGA_PHASE_INDEX:
		return "indexing";
	case PROGRESS_PGROONGA_PHASE_INDEX_LOAD:
		return "indexing (loading)";
	case PROGRESS_PGROONGA_PHASE_INDEX_COMMIT:
		return "indexing (committing)";
	case PROGRESS_PGROONGA_PHASE_DONE:
		return "done";
	default:
		return NULL;
	}
}

static bool
pgroonga_validate(Oid opClassOid)
{
	return true;
}

static Size
#if PG_VERSION_NUM >= 180000
pgroonga_estimateparallelscan(Relation indexRelation, int nkeys, int norderbys)
#elif PG_VERSION_NUM >= 170000
pgroonga_estimateparallelscan(int nkeys, int norderbys)
#else
pgroonga_estimateparallelscan(void)
#endif
{
	return sizeof(PGrnParallelScanDescData);
}

static void
pgroonga_initparallelscan(void *target)
{
	PGrnParallelScanDesc pgrnParallelScan = (PGrnParallelScanDesc) target;

	PGRN_TRACE_LOG_ENTER();

	SpinLockInit(&(pgrnParallelScan->mutex));
	pgrnParallelScan->scanning = false;

	PGRN_TRACE_LOG_EXIT();
}

static void
pgroonga_parallelrescan(IndexScanDesc scan)
{
	ParallelIndexScanDesc parallelScan = scan->parallel_scan;
	PGrnParallelScanDesc pgrnParallelScan =
		OffsetToPointer((void *) (parallelScan),
						PGRN_PARALLEL_SCAN_GET_PS_OFFSET_AM(parallelScan));

	PGRN_TRACE_LOG_ENTER();

	pgrnParallelScan->scanning = false;

	PGRN_TRACE_LOG_EXIT();
}

static bool
PGrnParallelScanAcquire(IndexScanDesc scan)
{
	PGrnScanOpaque so = (PGrnScanOpaque) scan->opaque;
	ParallelIndexScanDesc parallelScan = scan->parallel_scan;
	PGrnParallelScanDesc pgrnParallelScan =
		OffsetToPointer((void *) (parallelScan),
						PGRN_PARALLEL_SCAN_GET_PS_OFFSET_AM(parallelScan));
	bool acquired = false;

	if (so->indexCursor)
		return true;
	if (so->tableCursor)
		return true;

	SpinLockAcquire(&(pgrnParallelScan->mutex));
	if (!pgrnParallelScan->scanning)
	{
		acquired = true;
		pgrnParallelScan->scanning = true;
	}
	SpinLockRelease(&(pgrnParallelScan->mutex));
	return acquired;
}

#ifdef PGRN_SUPPORT_AMTRANSLATE_ROUTINE
static CompareType
pgroonga_translatestrategy(StrategyNumber strategy, Oid opfamily)
{
	switch (strategy)
	{
	case PGrnLessStrategyNumber:
		return COMPARE_LT;
	case PGrnLessEqualStrategyNumber:
		return COMPARE_LE;
	case PGrnEqualStrategyNumber:
		return COMPARE_EQ;
	case PGrnGreaterStrategyNumber:
		return COMPARE_GT;
	case PGrnGreaterEqualStrategyNumber:
		return COMPARE_GE;
	default:
		return COMPARE_INVALID;
	}
}

static StrategyNumber
pgroonga_translatecmptype(CompareType cmptype, Oid opfamily)
{
	switch (cmptype)
	{
	case COMPARE_LT:
		return PGrnLessStrategyNumber;
	case COMPARE_LE:
		return PGrnLessEqualStrategyNumber;
	case COMPARE_EQ:
		return PGrnEqualStrategyNumber;
	case COMPARE_GT:
		return PGrnGreaterStrategyNumber;
	case COMPARE_GE:
		return PGrnGreaterEqualStrategyNumber;
	default:
		return InvalidStrategy;
	}
}
#endif

Datum
pgroonga_handler(PG_FUNCTION_ARGS)
{
	IndexAmRoutine *routine = makeNode(IndexAmRoutine);

	routine->amstrategies = PGRN_N_STRATEGIES;
	routine->amsupport = 0;
	routine->amcanorder = true;
	routine->amcanorderbyop = true;
	routine->amcanbackward = true;
	routine->amcanunique = true;
	routine->amcanmulticol = true;
	routine->amoptionalkey = true;
	routine->amsearcharray = true;
	routine->amsearchnulls = false;
	routine->amstorage = false;
	routine->amclusterable = true;
	routine->ampredlocks = false;
	routine->amcanparallel = true;
#ifdef PGRN_SUPPORT_PARALLEL_INDEX_BUILD
	routine->amcanbuildparallel = true;
#endif
	routine->amcaninclude = true;
	routine->amusemaintenanceworkmem = false;
	routine->amparallelvacuumoptions = VACUUM_OPTION_PARALLEL_BULKDEL;
	routine->amkeytype = InvalidOid;

	routine->aminsert = pgroonga_insert;
	routine->ambeginscan = pgroonga_beginscan;
	routine->amgettuple = pgroonga_gettuple;
	routine->amgetbitmap = pgroonga_getbitmap;
	routine->amrescan = pgroonga_rescan;
	routine->amendscan = pgroonga_endscan;
	routine->ammarkpos = NULL;
	routine->amrestrpos = NULL;
	routine->ambuild = pgroonga_build;
	routine->ambuildempty = pgroonga_buildempty;
	routine->ambulkdelete = pgroonga_bulkdelete;
	routine->amvacuumcleanup = pgroonga_vacuumcleanup;
	routine->amcanreturn = pgroonga_canreturn;
	routine->amcostestimate = pgroonga_costestimate;
	routine->amoptions = pgroonga_options;
	routine->ambuildphasename = pgroonga_buildphrasename;
	routine->amvalidate = pgroonga_validate;
	routine->amestimateparallelscan = pgroonga_estimateparallelscan;
	routine->aminitparallelscan = pgroonga_initparallelscan;
	routine->amparallelrescan = pgroonga_parallelrescan;
#ifdef PGRN_SUPPORT_AMTRANSLATE_ROUTINE
	routine->amtranslatecmptype = pgroonga_translatecmptype;
	routine->amtranslatestrategy = pgroonga_translatestrategy;
#endif

	PG_RETURN_POINTER(routine);
}

bool
PGrnIndexIsPGroonga(Relation index)
{
	if (!index->rd_indam)
		return false;
	return index->rd_indam->aminsert == pgroonga_insert;
}
