#include "btree_gist.h"
#include "btree_utils_num.h"

typedef struct float4key
{
   float4    lower;
   float4    upper;
}  float4KEY;

/*
** float4 ops
*/
PG_FUNCTION_INFO_V1(gbt_float4_compress);
PG_FUNCTION_INFO_V1(gbt_float4_union);
PG_FUNCTION_INFO_V1(gbt_float4_picksplit);
PG_FUNCTION_INFO_V1(gbt_float4_consistent);
PG_FUNCTION_INFO_V1(gbt_float4_penalty);
PG_FUNCTION_INFO_V1(gbt_float4_same);

Datum    gbt_float4_compress(PG_FUNCTION_ARGS);
Datum    gbt_float4_union(PG_FUNCTION_ARGS);
Datum    gbt_float4_picksplit(PG_FUNCTION_ARGS);
Datum    gbt_float4_consistent(PG_FUNCTION_ARGS);
Datum    gbt_float4_penalty(PG_FUNCTION_ARGS);
Datum    gbt_float4_same(PG_FUNCTION_ARGS);

static bool     gbt_float4gt     (const void *a, const void *b)
{
  return ( *((float4*)a) >  *((float4*)b) ); 
}
static bool     gbt_float4ge     (const void *a, const void *b)
{
  return ( *((float4*)a) >= *((float4*)b) ); 
}
static bool     gbt_float4eq     (const void *a, const void *b)
{
  return ( *((float4*)a) == *((float4*)b) ); 
}
static bool     gbt_float4le     (const void *a, const void *b)
{
  return ( *((float4*)a) <= *((float4*)b) ); 
}
static bool     gbt_float4lt     (const void *a, const void *b)
{
  return ( *((float4*)a) <  *((float4*)b) ); 
}

static int
gbt_float4key_cmp(const void *a, const void *b)
{

  if ( *(float4*)&(((Nsrt *) a)->t[0]) >  *(float4*)&(((Nsrt *) b)->t[0]) ){
    return 1;
  } else
  if ( *(float4*)&(((Nsrt *) a)->t[0]) <  *(float4*)&(((Nsrt *) b)->t[0]) ){
    return -1;
  }
  return  0;

}


static const gbtree_ninfo tinfo = 
{ 
  gbt_t_float4,
  sizeof(float4),
  gbt_float4gt,
  gbt_float4ge,
  gbt_float4eq,
  gbt_float4le,
  gbt_float4lt,
  gbt_float4key_cmp
};


/**************************************************
 * float4 ops
 **************************************************/


Datum
gbt_float4_compress(PG_FUNCTION_ARGS)
{
    GISTENTRY  *entry  = (GISTENTRY *) PG_GETARG_POINTER(0);
    GISTENTRY  *retval = NULL;
    PG_RETURN_POINTER( gbt_num_compress( retval , entry , &tinfo ));
}


Datum
gbt_float4_consistent(PG_FUNCTION_ARGS)
{
    GISTENTRY        *entry = (GISTENTRY *) PG_GETARG_POINTER(0);
    float4             query = PG_GETARG_FLOAT4(1);
    float4KEY           *kkk = (float4KEY *) DatumGetPointer(entry->key);
    GBT_NUMKEY_R        key ;
    StrategyNumber strategy = (StrategyNumber) PG_GETARG_UINT16(2);
    key.lower = (GBT_NUMKEY*) &kkk->lower ;
    key.upper = (GBT_NUMKEY*) &kkk->upper ;

    PG_RETURN_BOOL( 
      gbt_num_consistent( &key, (void*)&query,&strategy,GIST_LEAF(entry),&tinfo)
    );
}


Datum
gbt_float4_union(PG_FUNCTION_ARGS)
{
    GistEntryVector     *entryvec = (GistEntryVector *) PG_GETARG_POINTER(0);
    void                     *out = palloc(sizeof(float4KEY));
    *(int *) PG_GETARG_POINTER(1) = sizeof(float4KEY);
    PG_RETURN_POINTER( gbt_num_union ( (void*)out, entryvec, &tinfo ) );
}


Datum
gbt_float4_penalty(PG_FUNCTION_ARGS)
{
  float4KEY    *origentry = (float4KEY *) DatumGetPointer(((GISTENTRY *) PG_GETARG_POINTER(0))->key);
  float4KEY    *newentry  = (float4KEY *) DatumGetPointer(((GISTENTRY *) PG_GETARG_POINTER(1))->key);
  float           *result = (float *) PG_GETARG_POINTER(2);

  float4              res ;

  *result = 0.0;
 
  res     = Max(newentry->upper - origentry->upper, 0) +
            Max(origentry->lower - newentry->lower, 0);

  if ( res > 0 ){
    *result += FLT_MIN ;
    *result += (float) ( res / ( (double) ( res + origentry->upper - origentry->lower ) ) );
    *result *= ( FLT_MAX / ( ( (GISTENTRY *) PG_GETARG_POINTER(0))->rel->rd_att->natts + 1 ) );
  }

  PG_RETURN_POINTER(result);

}

Datum
gbt_float4_picksplit(PG_FUNCTION_ARGS)
{
  PG_RETURN_POINTER(gbt_num_picksplit(
      (GistEntryVector *) PG_GETARG_POINTER(0),
      (GIST_SPLITVEC *) PG_GETARG_POINTER(1),
      &tinfo
  ));
}

Datum
gbt_float4_same(PG_FUNCTION_ARGS)
{
  float4KEY    *b1 = (float4KEY *) PG_GETARG_POINTER(0);
  float4KEY    *b2 = (float4KEY *) PG_GETARG_POINTER(1);
  bool     *result = (bool *) PG_GETARG_POINTER(2);

  *result  = gbt_num_same ( (void*)b1, (void*)b2, &tinfo );
  PG_RETURN_POINTER(result);
}