/* 
 * interface functions to tscfg 
 * Teodor Sigaev <teodor@sigaev.ru>
 */
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <locale.h>

#include "postgres.h"
#include "fmgr.h"
#include "utils/array.h"
#include "catalog/pg_type.h"
#include "executor/spi.h"

#include "ts_cfg.h"
#include "dict.h"
#include "wparser.h"
#include "snmap.h"
#include "common.h"
#include "tsvector.h"

/*********top interface**********/

static void *plan_getcfg_bylocale=NULL;
static void *plan_getcfg=NULL;
static void *plan_getmap=NULL;
static void *plan_name2id=NULL;
static Oid current_cfg_id=0;

void
init_cfg(Oid id, TSCfgInfo *cfg) {
	Oid arg[2]={ OIDOID, OIDOID };
	bool isnull;
	Datum pars[2]={ ObjectIdGetDatum(id), ObjectIdGetDatum(id) } ;
	int stat,i,j;
	text *ptr;
	text *prsname=NULL;
	MemoryContext	oldcontext;

	memset(cfg,0,sizeof(TSCfgInfo));
	SPI_connect();
	if ( !plan_getcfg ) {
		plan_getcfg = SPI_saveplan( SPI_prepare( "select prs_name from pg_ts_cfg where oid = $1" , 1, arg ) );
		if ( !plan_getcfg ) 
			ts_error(ERROR, "SPI_prepare() failed");
	}

	stat = SPI_execp(plan_getcfg, pars, " ", 1);
	if ( stat < 0 )
		ts_error (ERROR, "SPI_execp return %d", stat);
	if ( SPI_processed > 0 ) {
		prsname = (text*) DatumGetPointer( 
			SPI_getbinval(SPI_tuptable->vals[0], SPI_tuptable->tupdesc, 1, &isnull) 
		);
		oldcontext = MemoryContextSwitchTo(TopMemoryContext);
		prsname = ptextdup( prsname );
		MemoryContextSwitchTo(oldcontext);
		
		cfg->id=id;
	} else 
		ts_error(ERROR, "No tsearch cfg with id %d", id);

	arg[0]=TEXTOID;
	if ( !plan_getmap ) {
		plan_getmap = SPI_saveplan( SPI_prepare( "select lt.tokid, pg_ts_cfgmap.dict_name from pg_ts_cfgmap, pg_ts_cfg, token_type( $1 ) as lt where lt.alias = pg_ts_cfgmap.tok_alias and pg_ts_cfgmap.ts_name = pg_ts_cfg.ts_name and pg_ts_cfg.oid= $2 order by lt.tokid desc;" , 2, arg ) );
		if ( !plan_getmap )
			ts_error(ERROR, "SPI_prepare() failed");
	}

	pars[0]=PointerGetDatum( prsname );
	stat = SPI_execp(plan_getmap, pars, " ", 0);
	if ( stat < 0 )
		ts_error (ERROR, "SPI_execp return %d", stat);
	if ( SPI_processed <= 0 )
		ts_error(ERROR, "No parser with id %d", id);

	for(i=0;i<SPI_processed;i++) {
		int lexid = DatumGetInt32(SPI_getbinval(SPI_tuptable->vals[i], SPI_tuptable->tupdesc, 1, &isnull));
		ArrayType *toasted_a = (ArrayType*)PointerGetDatum(SPI_getbinval(SPI_tuptable->vals[i], SPI_tuptable->tupdesc, 2, &isnull));
		ArrayType *a;

		if ( !cfg->map ) {
			cfg->len=lexid+1;
			cfg->map = (ListDictionary*)malloc( sizeof(ListDictionary)*cfg->len );
			if ( !cfg->map )
				ereport(ERROR,
						(errcode(ERRCODE_OUT_OF_MEMORY),
						 errmsg("out of memory")));
			memset( cfg->map, 0, sizeof(ListDictionary)*cfg->len );
		}

		if (isnull)
			continue;

		a=(ArrayType*)PointerGetDatum( PG_DETOAST_DATUM( DatumGetPointer(toasted_a) ) );
		
		if ( ARR_NDIM(a) != 1 )
			ts_error(ERROR,"Wrong dimension");
		if ( ARRNELEMS(a) < 1 )
			continue;

		cfg->map[lexid].len=ARRNELEMS(a);
		cfg->map[lexid].dict_id=(Datum*)malloc( sizeof(Datum)*cfg->map[lexid].len );
		memset(cfg->map[lexid].dict_id,0,sizeof(Datum)*cfg->map[lexid].len );
		ptr=(text*)ARR_DATA_PTR(a);
		oldcontext = MemoryContextSwitchTo(TopMemoryContext);
		for(j=0;j<cfg->map[lexid].len;j++) {
			cfg->map[lexid].dict_id[j] = PointerGetDatum(ptextdup(ptr));
			ptr=NEXTVAL(ptr);
		} 
		MemoryContextSwitchTo(oldcontext);

		if ( a != toasted_a ) 
			pfree(a);
	}
	
	SPI_finish();
	cfg->prs_id = name2id_prs( prsname );
	pfree(prsname);
	for(i=0;i<cfg->len;i++) {
		for(j=0;j<cfg->map[i].len;j++) {
			ptr = (text*)DatumGetPointer( cfg->map[i].dict_id[j] );
			cfg->map[i].dict_id[j] = ObjectIdGetDatum( name2id_dict(ptr) );
			pfree(ptr);
		}
	}
}

typedef struct {
	TSCfgInfo	*last_cfg;
	int		len;
	int		reallen;
	TSCfgInfo	*list;
	SNMap		name2id_map;
} CFGList;

static CFGList CList = {NULL,0,0,NULL,{0,0,NULL}};

void
reset_cfg(void) {
        freeSNMap( &(CList.name2id_map) );
        if ( CList.list ) {
		int i,j;
		for(i=0;i<CList.len;i++)
			if ( CList.list[i].map ) {
				for(j=0;j<CList.list[i].len;j++)
					if ( CList.list[i].map[j].dict_id )
						free(CList.list[i].map[j].dict_id);
				free( CList.list[i].map );
			}
                free(CList.list);
	}
        memset(&CList,0,sizeof(CFGList));
}

static int
comparecfg(const void *a, const void *b) {
	return ((TSCfgInfo*)a)->id - ((TSCfgInfo*)b)->id;
}

TSCfgInfo *
findcfg(Oid id) {
	/* last used cfg */
	if ( CList.last_cfg && CList.last_cfg->id==id )
		return CList.last_cfg;

	/* already used cfg */
	if ( CList.len != 0 ) {
		TSCfgInfo key;
		key.id=id;
		CList.last_cfg = bsearch(&key, CList.list, CList.len, sizeof(TSCfgInfo), comparecfg);
		if ( CList.last_cfg != NULL )
			return CList.last_cfg;
	}

	/* last chance */
	if ( CList.len==CList.reallen ) {
		TSCfgInfo *tmp;
		int reallen = ( CList.reallen ) ? 2*CList.reallen : 16;
		tmp=(TSCfgInfo*)realloc(CList.list,sizeof(TSCfgInfo)*reallen);
		if ( !tmp ) 
			ts_error(ERROR,"No memory");
		CList.reallen=reallen;
		CList.list=tmp;
	}
	CList.last_cfg=&(CList.list[CList.len]);
	init_cfg(id, CList.last_cfg);
	CList.len++;
	qsort(CList.list, CList.len, sizeof(TSCfgInfo), comparecfg);
	return findcfg(id); /* qsort changed order!! */;
}


Oid
name2id_cfg(text *name) {
	Oid arg[1]={ TEXTOID };
	bool isnull;
	Datum pars[1]={ PointerGetDatum(name) };
	int stat;
	Oid id=findSNMap_t( &(CList.name2id_map), name );
	
	if ( id ) 
		return id;
	
	SPI_connect();
	if ( !plan_name2id ) {
		plan_name2id = SPI_saveplan( SPI_prepare( "select oid from pg_ts_cfg where ts_name = $1" , 1, arg ) );
		if ( !plan_name2id ) 
			/* internal error */
			elog(ERROR, "SPI_prepare() failed");
	}

	stat = SPI_execp(plan_name2id, pars, " ", 1);
	if ( stat < 0 )
		/* internal error */
		elog (ERROR, "SPI_execp return %d", stat);
	if ( SPI_processed > 0 ) {
		id=DatumGetObjectId( SPI_getbinval(SPI_tuptable->vals[0], SPI_tuptable->tupdesc, 1, &isnull) );
		if ( isnull ) 
			ereport(ERROR,
					(errcode(ERRCODE_CONFIG_FILE_ERROR),
					 errmsg("null id for tsearch config")));
	} else 
		ereport(ERROR,
				(errcode(ERRCODE_CONFIG_FILE_ERROR),
				 errmsg("no tsearch config")));

	SPI_finish();
	addSNMap_t( &(CList.name2id_map), name, id );
	return id;
}


void 
parsetext_v2(TSCfgInfo *cfg, PRSTEXT * prs, char *buf, int4 buflen) {
	int	type, lenlemm, i;
	char	*lemm=NULL;
	WParserInfo *prsobj = findprs(cfg->prs_id);

	prsobj->prs=(void*)DatumGetPointer(
		FunctionCall2(
			&(prsobj->start_info),
			PointerGetDatum(buf),
			Int32GetDatum(buflen)
		)
	);

	while( ( type=DatumGetInt32(FunctionCall3(
			&(prsobj->getlexeme_info),
			PointerGetDatum(prsobj->prs),
			PointerGetDatum(&lemm),
			PointerGetDatum(&lenlemm))) ) != 0 ) {

		if ( lenlemm >= MAXSTRLEN )
			ereport(ERROR,
					(errcode(ERRCODE_SYNTAX_ERROR),
					 errmsg("word is too long")));

		if ( type >= cfg->len ) /* skip this type of lexem */
			continue; 

		for(i=0;i<cfg->map[type].len;i++) {
			DictInfo	*dict=finddict( DatumGetObjectId(cfg->map[type].dict_id[i]) );
			char	**norms, **ptr;
	
			norms = ptr = (char**)DatumGetPointer(
				FunctionCall3(
					&(dict->lexize_info),
					PointerGetDatum(dict->dictionary),
					PointerGetDatum(lemm),
					PointerGetDatum(lenlemm)
				)
			);
			if ( !norms ) /* dictionary doesn't know this lexem */
				continue;

			prs->pos++; /*set pos*/

			while( *ptr ) {
				if (prs->curwords == prs->lenwords) {
					prs->lenwords *= 2;
					prs->words = (WORD *) repalloc((void *) prs->words, prs->lenwords * sizeof(WORD));
				}

				prs->words[prs->curwords].len = strlen(*ptr);
				prs->words[prs->curwords].word = *ptr;
				prs->words[prs->curwords].alen = 0;
				prs->words[prs->curwords].pos.pos = LIMITPOS(prs->pos);
				ptr++;
				prs->curwords++;
			}
			pfree(norms);
			break; /* lexem already normalized or is stop word*/
		}
	}

	FunctionCall1(
		&(prsobj->end_info),
		PointerGetDatum(prsobj->prs)
	);
}

static void
hladdword(HLPRSTEXT * prs, char *buf, int4 buflen, int type) {
	while (prs->curwords >= prs->lenwords) {
		prs->lenwords *= 2;
		prs->words = (HLWORD *) repalloc((void *) prs->words, prs->lenwords * sizeof(HLWORD));
	}
	memset( &(prs->words[prs->curwords]), 0, sizeof(HLWORD) ); 
	prs->words[prs->curwords].type = (uint8)type;
	prs->words[prs->curwords].len = buflen;	
	prs->words[prs->curwords].word = palloc(buflen);
	memcpy(prs->words[prs->curwords].word, buf, buflen);
	prs->curwords++;	
}

static void
hlfinditem(HLPRSTEXT * prs, QUERYTYPE *query, char *buf, int buflen ) {
	int i;
	ITEM	*item=GETQUERY(query);
	HLWORD	*word=&( prs->words[prs->curwords-1] );

	while (prs->curwords + query->size >= prs->lenwords) {
		prs->lenwords *= 2;
		prs->words = (HLWORD *) repalloc((void *) prs->words, prs->lenwords * sizeof(HLWORD));
	}

	for(i=0; i<query->size; i++) { 
		if ( item->type == VAL && item->length == buflen && strncmp( GETOPERAND(query) + item->distance, buf, buflen )==0 ) {
			if ( word->item ) {
				memcpy( &(prs->words[prs->curwords]), word, sizeof(HLWORD) );
				prs->words[prs->curwords].item=item;
				prs->words[prs->curwords].repeated=1;
				prs->curwords++;
			} else 
				word->item=item;	
		}
		item++;
	}
}

void 
hlparsetext(TSCfgInfo *cfg, HLPRSTEXT * prs, QUERYTYPE *query, char *buf, int4 buflen) {
	int	type, lenlemm, i;
	char	*lemm=NULL;
	WParserInfo *prsobj = findprs(cfg->prs_id);

	prsobj->prs=(void*)DatumGetPointer(
		FunctionCall2(
			&(prsobj->start_info),
			PointerGetDatum(buf),
			Int32GetDatum(buflen)
		)
	);

	while( ( type=DatumGetInt32(FunctionCall3(
			&(prsobj->getlexeme_info),
			PointerGetDatum(prsobj->prs),
			PointerGetDatum(&lemm),
			PointerGetDatum(&lenlemm))) ) != 0 ) {

		if ( lenlemm >= MAXSTRLEN )
			ereport(ERROR,
					(errcode(ERRCODE_SYNTAX_ERROR),
					 errmsg("word is too long")));

		hladdword(prs,lemm,lenlemm,type);

		if ( type >= cfg->len ) 
			continue; 

		for(i=0;i<cfg->map[type].len;i++) {
			DictInfo	*dict=finddict( DatumGetObjectId(cfg->map[type].dict_id[i]) );
			char	**norms, **ptr;
	
			norms = ptr = (char**)DatumGetPointer(
				FunctionCall3(
					&(dict->lexize_info),
					PointerGetDatum(dict->dictionary),
					PointerGetDatum(lemm),
					PointerGetDatum(lenlemm)
				)
			);
			if ( !norms ) /* dictionary doesn't know this lexem */
				continue;

			while( *ptr ) {
				hlfinditem(prs,query,*ptr,strlen(*ptr));
				pfree(*ptr);
				ptr++;
			}
			pfree(norms);
			break; /* lexem already normalized or is stop word*/
		}
	}

	FunctionCall1(
		&(prsobj->end_info),
		PointerGetDatum(prsobj->prs)
	);
}

text* 
genhl(HLPRSTEXT * prs) {
	text *out;
	int len=128;
	char *ptr;
	HLWORD	*wrd=prs->words;

	out = (text*)palloc( len );
	ptr=((char*)out) + VARHDRSZ;

	while( wrd - prs->words < prs->curwords ) {
		while (  wrd->len + prs->stopsellen + prs->startsellen + (ptr - ((char*)out)) >= len ) {
			int dist = ptr - ((char*)out);
			len*= 2;
			out = (text *) repalloc(out, len);
			ptr=((char*)out) + dist;
		}

		if ( wrd->in && !wrd->skip && !wrd->repeated ) {
			if ( wrd->replace ) {
				*ptr=' ';
				ptr++;
			} else {
				if (wrd->selected) {
					memcpy(ptr,prs->startsel,prs->startsellen);
					ptr+=prs->startsellen;
				}
				memcpy(ptr,wrd->word,wrd->len);
				ptr+=wrd->len;
				if (wrd->selected) {
					memcpy(ptr,prs->stopsel,prs->stopsellen);
					ptr+=prs->stopsellen;
				}
			}
		}

		if ( !wrd->repeated )
			pfree(wrd->word);

		wrd++;
	}

	VARATT_SIZEP(out)=ptr - ((char*)out);
	return out; 
}

int  
get_currcfg(void) {
	Oid arg[1]={ TEXTOID };
	const char *curlocale;
	Datum pars[1];
	bool isnull;
	int stat;

	if ( current_cfg_id > 0 )
		return current_cfg_id;

	SPI_connect();
	if ( !plan_getcfg_bylocale ) {
		plan_getcfg_bylocale=SPI_saveplan( SPI_prepare( "select oid from pg_ts_cfg where locale = $1 ", 1, arg ) );
		if ( !plan_getcfg_bylocale )
			/* internal error */
			elog(ERROR, "SPI_prepare() failed");
	}

	curlocale = setlocale(LC_CTYPE, NULL);
	pars[0] = PointerGetDatum( char2text((char*)curlocale) );
	stat = SPI_execp(plan_getcfg_bylocale, pars, " ", 1);

	if ( stat < 0 )
		/* internal error */
		elog (ERROR, "SPI_execp return %d", stat);
	if ( SPI_processed > 0 )
		current_cfg_id = DatumGetObjectId( SPI_getbinval(SPI_tuptable->vals[0], SPI_tuptable->tupdesc, 1, &isnull) );
	else 
		ereport(ERROR,
				(errcode(ERRCODE_CONFIG_FILE_ERROR),
				 errmsg("could not find tsearch config by locale")));

	pfree(DatumGetPointer(pars[0]));
	SPI_finish();
	return current_cfg_id;
}

PG_FUNCTION_INFO_V1(set_curcfg);
Datum set_curcfg(PG_FUNCTION_ARGS);
Datum
set_curcfg(PG_FUNCTION_ARGS) {
        findcfg(PG_GETARG_OID(0));
        current_cfg_id=PG_GETARG_OID(0);
        PG_RETURN_VOID();
}
                
PG_FUNCTION_INFO_V1(set_curcfg_byname);
Datum set_curcfg_byname(PG_FUNCTION_ARGS);
Datum
set_curcfg_byname(PG_FUNCTION_ARGS) {
        text *name=PG_GETARG_TEXT_P(0);
   
        DirectFunctionCall1(
                set_curcfg,
                ObjectIdGetDatum( name2id_cfg(name) )
        );
        PG_FREE_IF_COPY(name, 0);
        PG_RETURN_VOID();      
}       

PG_FUNCTION_INFO_V1(show_curcfg);
Datum show_curcfg(PG_FUNCTION_ARGS);
Datum
show_curcfg(PG_FUNCTION_ARGS) {
	PG_RETURN_OID( get_currcfg() ); 
}

PG_FUNCTION_INFO_V1(reset_tsearch);
Datum reset_tsearch(PG_FUNCTION_ARGS);
Datum
reset_tsearch(PG_FUNCTION_ARGS) {
	ts_error(NOTICE,"TSearch cache cleaned");
	PG_RETURN_VOID(); 
}