#include "btree_gist.h"
#include "btree_utils_var.h"
#include "utils/builtins.h"
#include "utils/varbit.h"


/*
** Bit ops
*/
PG_FUNCTION_INFO_V1(gbt_bit_compress);
PG_FUNCTION_INFO_V1(gbt_bit_union);
PG_FUNCTION_INFO_V1(gbt_bit_picksplit);
PG_FUNCTION_INFO_V1(gbt_bit_consistent);
PG_FUNCTION_INFO_V1(gbt_bit_penalty);
PG_FUNCTION_INFO_V1(gbt_bit_same);

Datum    gbt_bit_compress(PG_FUNCTION_ARGS);
Datum    gbt_bit_union(PG_FUNCTION_ARGS);
Datum    gbt_bit_picksplit(PG_FUNCTION_ARGS);
Datum    gbt_bit_consistent(PG_FUNCTION_ARGS);
Datum    gbt_bit_penalty(PG_FUNCTION_ARGS);
Datum    gbt_bit_same(PG_FUNCTION_ARGS);



/* define for comparison */

static bool     gbt_bitgt     (const void *a, const void *b)
{
  return ( DatumGetBool(DirectFunctionCall2( bitgt ,PointerGetDatum( a ),PointerGetDatum( b ) ) ) );
}

static bool     gbt_bitge     (const void *a, const void *b)
{
  return ( DatumGetBool(DirectFunctionCall2( bitge ,PointerGetDatum( a ),PointerGetDatum( b ) ) ) );
}

static bool     gbt_biteq     (const void *a, const void *b)
{
  return ( DatumGetBool(DirectFunctionCall2( biteq ,PointerGetDatum( a ),PointerGetDatum( b ) ) ) );
}

static bool     gbt_bitle     (const void *a, const void *b)
{
  return ( DatumGetBool(DirectFunctionCall2( bitle ,PointerGetDatum( a ),PointerGetDatum( b ) ) ) );
}

static bool     gbt_bitlt     (const void *a, const void *b)
{
  return ( DatumGetBool(DirectFunctionCall2( bitlt ,PointerGetDatum( a ),PointerGetDatum( b ) ) ) );
}

static int32 gbt_bitcmp ( const bytea * a , const bytea * b )
{
  return
    ( DatumGetInt32(DirectFunctionCall2(byteacmp,PointerGetDatum(a),PointerGetDatum(b) ) ) );
}
 

static bytea *
gbt_bit_xfrm ( bytea * leaf )
{
    bytea  * out = leaf;
    int        s = VARBITBYTES(leaf) + VARHDRSZ;

    out  = palloc ( s );
    VARATT_SIZEP(out) = s;
    memcpy ( (void*)VARDATA(out), (void*)VARBITS(leaf), VARBITBYTES(leaf) );
    return out;
}




static GBT_VARKEY * gbt_bit_l2n ( GBT_VARKEY * leaf )
{

  GBT_VARKEY   *out = leaf ;
  GBT_VARKEY_R    r = gbt_var_key_readable ( leaf );
  bytea          *o ;

  o  = gbt_bit_xfrm (r.lower);
  r.upper = r.lower =  o;
  out = gbt_var_key_copy( &r, TRUE );
  pfree(o);

  return out;

}

static const gbtree_vinfo tinfo =
{
  gbt_t_bit,
  FALSE,
  TRUE,
  gbt_bitgt,
  gbt_bitge,
  gbt_biteq,
  gbt_bitle,
  gbt_bitlt,
  gbt_bitcmp,
  gbt_bit_l2n
};


/**************************************************
 * Bit ops
 **************************************************/

Datum
gbt_bit_compress (PG_FUNCTION_ARGS)
{
  GISTENTRY        *entry = (GISTENTRY *) PG_GETARG_POINTER(0);
  PG_RETURN_POINTER ( gbt_var_compress( entry, &tinfo ) );
}

Datum
gbt_bit_consistent(PG_FUNCTION_ARGS)
{
  GISTENTRY        *entry = (GISTENTRY *) PG_GETARG_POINTER(0);
  GBT_VARKEY       *ktst  = (GBT_VARKEY   *) DatumGetPointer ( entry->key ) ;
  GBT_VARKEY        *key  = (GBT_VARKEY   *) DatumGetPointer ( PG_DETOAST_DATUM( entry->key ) );
  void             *qtst  = ( void * ) DatumGetPointer( PG_GETARG_DATUM(1) );
  void            *query  = ( void * ) DatumGetByteaP ( PG_GETARG_DATUM(1) );
  StrategyNumber strategy = (StrategyNumber) PG_GETARG_UINT16(2);
  bool    retval          = FALSE;
  GBT_VARKEY_R          r =  gbt_var_key_readable ( key );

  if ( GIST_LEAF(entry) )
  {
    retval = gbt_var_consistent( &r, query, &strategy, TRUE, &tinfo );
  } else {
    bytea * q = gbt_bit_xfrm ( ( bytea * ) query );
    retval    = gbt_var_consistent( &r, (void*)q, &strategy, FALSE, &tinfo );
    pfree(q);
  }

  if ( ktst != key ){
    pfree ( key );
  }
  if ( qtst != query ){
    pfree ( query );
  }
  PG_RETURN_BOOL(retval);
}



Datum
gbt_bit_union(PG_FUNCTION_ARGS)
{
    GistEntryVector * entryvec = (GistEntryVector *) PG_GETARG_POINTER(0);
    int32           * size     = (int *)   PG_GETARG_POINTER(1);
    PG_RETURN_POINTER( gbt_var_union ( entryvec , size , &tinfo ) );
}
 

Datum
gbt_bit_picksplit(PG_FUNCTION_ARGS)
{
    GistEntryVector *entryvec = (GistEntryVector *) PG_GETARG_POINTER(0);
    GIST_SPLITVEC          *v = (GIST_SPLITVEC *) PG_GETARG_POINTER(1);
    gbt_var_picksplit ( entryvec, v, &tinfo );
    PG_RETURN_POINTER(v);
}

Datum
gbt_bit_same(PG_FUNCTION_ARGS)
{
    Datum d1 = PG_GETARG_DATUM(0);
    Datum d2 = PG_GETARG_DATUM(1);
    bool       *result = (bool *) PG_GETARG_POINTER(2);
    PG_RETURN_POINTER( gbt_var_same ( result, d1 , d2 , &tinfo ));
}


Datum
gbt_bit_penalty(PG_FUNCTION_ARGS)
{
    float      *result   = (float *)     PG_GETARG_POINTER(2);
    GISTENTRY *      o   = (GISTENTRY *) PG_GETARG_POINTER(0);
    GISTENTRY *      n   = (GISTENTRY *) PG_GETARG_POINTER(1);
    PG_RETURN_POINTER( gbt_var_penalty ( result ,o , n, &tinfo ) );
}