#ifndef __TRGM_H__
#define __TRGM_H__

#include "postgres.h"

#include "access/gist.h"
#include "access/itup.h"
#include "utils/elog.h"
#include "utils/palloc.h"
#include "utils/builtins.h"
#include "storage/bufpage.h"

/* options */
#define LPADDING        2
#define RPADDING        1
#define KEEPONLYALNUM
#define IGNORECASE  
#define DIVUNION


typedef char trgm[3];

#define CMPCHAR(a,b) ( ((a)==(b)) ? 0 : ( ((a)<(b)) ? -1 : 1 ) )
#define CMPPCHAR(a,b,i)  CMPCHAR( *(((char*)(a))+i), *(((char*)(b))+i) ) 
#define CMPTRGM(a,b) ( CMPPCHAR(a,b,0) ? CMPPCHAR(a,b,0) : ( CMPPCHAR(a,b,1) ? CMPPCHAR(a,b,1) : CMPPCHAR(a,b,2) ) )

#define CPTRGM(a,b) do {		      	\
	*(((char*)(a))+0) = *(((char*)(b))+0);	\
	*(((char*)(a))+1) = *(((char*)(b))+1);	\
	*(((char*)(a))+2) = *(((char*)(b))+2);	\
} while(0);


typedef struct {
	int4	len;
	uint8	flag;
	char	data[1];
} TRGM;

#define TRGMHRDSIZE       (sizeof(int4)+sizeof(uint8))

/* gist */
#define BITBYTE 8
#define SIGLENINT  3               /* >122 => key will toast, so very slow!!! */
#define SIGLEN  ( sizeof(int)*SIGLENINT )

#define SIGLENBIT (SIGLEN*BITBYTE - 1) /* see makesign */ 

typedef char BITVEC[SIGLEN];
typedef char *BITVECP;

#define LOOPBYTE(a) \
                for(i=0;i<SIGLEN;i++) {\
                                a;\
                }

#define LOOPBIT(a) \
                for(i=0;i<SIGLENBIT;i++) {\
                                a;\
                }

#define GETBYTE(x,i) ( *( (BITVECP)(x) + (int)( (i) / BITBYTE ) ) )
#define GETBITBYTE(x,i) ( ((char)(x)) >> i & 0x01 )
#define CLRBIT(x,i)   GETBYTE(x,i) &= ~( 0x01 << ( (i) % BITBYTE ) )
#define SETBIT(x,i)   GETBYTE(x,i) |=  ( 0x01 << ( (i) % BITBYTE ) )
#define GETBIT(x,i) ( (GETBYTE(x,i) >> ( (i) % BITBYTE )) & 0x01 )

#define HASHVAL(val) (((unsigned int)(val)) % SIGLENBIT)
#define HASH(sign, val) SETBIT((sign), HASHVAL(val))

#define ARRKEY          0x01
#define SIGNKEY         0x02
#define ALLISTRUE       0x04
   
#define ISARRKEY(x) ( ((TRGM*)x)->flag & ARRKEY )
#define ISSIGNKEY(x)    ( ((TRGM*)x)->flag & SIGNKEY )
#define ISALLTRUE(x)    ( ((TRGM*)x)->flag & ALLISTRUE )

#define CALCGTSIZE(flag, len) ( TRGMHRDSIZE + ( ( (flag) & ARRKEY ) ? ((len)*sizeof(trgm)) : (((flag) & ALLISTRUE) ? 0 : SIGLEN) ) )
#define GETSIGN(x)      ( (BITVECP)( (char*)x+TRGMHRDSIZE ) )
#define GETARR(x)       ( (trgm*)( (char*)x+TRGMHRDSIZE ) )
#define ARRNELEM(x) ( ( ((TRGM*)x)->len - TRGMHRDSIZE )/sizeof(trgm) )

extern float4 trgm_limit;
TRGM* generate_trgm(char *str, int slen);
float4 cnt_sml(TRGM *trg1, TRGM *trg2);

#endif
