/*
 * contrib/btree_gist/btree_oid.c
 */
#include "postgres.h"
#include "knl/knl_variable.h"

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

typedef struct {
    Oid lower;
    Oid upper;
} oidKEY;

/*
** OID ops
*/
PG_FUNCTION_INFO_V1(gbt_oid_compress);
PG_FUNCTION_INFO_V1(gbt_oid_union);
PG_FUNCTION_INFO_V1(gbt_oid_picksplit);
PG_FUNCTION_INFO_V1(gbt_oid_consistent);
PG_FUNCTION_INFO_V1(gbt_oid_distance);
PG_FUNCTION_INFO_V1(gbt_oid_penalty);
PG_FUNCTION_INFO_V1(gbt_oid_same);

extern "C" Datum gbt_oid_compress(PG_FUNCTION_ARGS);
extern "C" Datum gbt_oid_union(PG_FUNCTION_ARGS);
extern "C" Datum gbt_oid_picksplit(PG_FUNCTION_ARGS);
extern "C" Datum gbt_oid_consistent(PG_FUNCTION_ARGS);
extern "C" Datum gbt_oid_distance(PG_FUNCTION_ARGS);
extern "C" Datum gbt_oid_penalty(PG_FUNCTION_ARGS);
extern "C" Datum gbt_oid_same(PG_FUNCTION_ARGS);

static bool gbt_oidgt(const void* a, const void* b)
{
    return (*((const Oid*)a) > *((const Oid*)b));
}
static bool gbt_oidge(const void* a, const void* b)
{
    return (*((const Oid*)a) >= *((const Oid*)b));
}
static bool gbt_oideq(const void* a, const void* b)
{
    return (*((const Oid*)a) == *((const Oid*)b));
}
static bool gbt_oidle(const void* a, const void* b)
{
    return (*((const Oid*)a) <= *((const Oid*)b));
}
static bool gbt_oidlt(const void* a, const void* b)
{
    return (*((const Oid*)a) < *((const Oid*)b));
}

static int gbt_oidkey_cmp(const void* a, const void* b)
{
    oidKEY* ia = (oidKEY*)(((const Nsrt*)a)->t);
    oidKEY* ib = (oidKEY*)(((const Nsrt*)b)->t);

    if (ia->lower == ib->lower) {
        if (ia->upper == ib->upper)
            return 0;

        return (ia->upper > ib->upper) ? 1 : -1;
    }

    return (ia->lower > ib->lower) ? 1 : -1;
}

static float8 gbt_oid_dist(const void* a, const void* b)
{
    Oid aa = *(const Oid*)a;
    Oid bb = *(const Oid*)b;

    if (aa < bb)
        return (float8)(bb - aa);
    else
        return (float8)(aa - bb);
}

static const gbtree_ninfo tinfo = {
    gbt_t_oid, sizeof(Oid), gbt_oidgt, gbt_oidge, gbt_oideq, gbt_oidle, gbt_oidlt, gbt_oidkey_cmp, gbt_oid_dist};

PG_FUNCTION_INFO_V1(oid_dist);
extern "C" Datum oid_dist(PG_FUNCTION_ARGS);
Datum oid_dist(PG_FUNCTION_ARGS)
{
    Oid a = PG_GETARG_OID(0);
    Oid b = PG_GETARG_OID(1);
    Oid res;

    if (a < b)
        res = b - a;
    else
        res = a - b;
    PG_RETURN_OID(res);
}

/**************************************************
 * Oid ops
 **************************************************/

Datum gbt_oid_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_oid_consistent(PG_FUNCTION_ARGS)
{
    GISTENTRY* entry = (GISTENTRY*)PG_GETARG_POINTER(0);
    Oid query = PG_GETARG_OID(1);
    StrategyNumber strategy = (StrategyNumber)PG_GETARG_UINT16(2);

    bool* recheck = (bool*)PG_GETARG_POINTER(4);
    oidKEY* kkk = (oidKEY*)DatumGetPointer(entry->key);
    GBT_NUMKEY_R key;

    /* All cases served by this function are exact */
    *recheck = false;

    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_oid_distance(PG_FUNCTION_ARGS)
{
    GISTENTRY* entry = (GISTENTRY*)PG_GETARG_POINTER(0);
    Oid query = PG_GETARG_OID(1);

    oidKEY* kkk = (oidKEY*)DatumGetPointer(entry->key);
    GBT_NUMKEY_R key;

    key.lower = (GBT_NUMKEY*)&kkk->lower;
    key.upper = (GBT_NUMKEY*)&kkk->upper;

    PG_RETURN_FLOAT8(gbt_num_distance(&key, (void*)&query, GIST_LEAF(entry), &tinfo));
}

Datum gbt_oid_union(PG_FUNCTION_ARGS)
{
    GistEntryVector* entryvec = (GistEntryVector*)PG_GETARG_POINTER(0);
    void* out = palloc(sizeof(oidKEY));

    *(int*)PG_GETARG_POINTER(1) = sizeof(oidKEY);
    PG_RETURN_POINTER(gbt_num_union((GBT_NUMKEY*)out, entryvec, &tinfo));
}

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

    penalty_num(result, origentry->lower, origentry->upper, newentry->lower, newentry->upper);

    PG_RETURN_POINTER(result);
}

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

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

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