#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"
#include "perlapi.h"
#include "ppport.h"

HE * get_entry(HE * he, U32 hash) {
    HE *entry = he;
    for(; entry; entry = HeNEXT(entry)) {
        if (HeHASH(entry) != hash){
            continue;
        }
    }
    if (!entry) entry = he;
    return entry;
}

MODULE = Hash::Bidirectional            PACKAGE = Hash::Bidirectional

char * pair(HV *hv, char *key, SV *value)
CODE:
    SV **key_ptr;
    SV **value_ptr;
    char *v = SvPVbyte_nolen(value);
    U32 hash = 0;
    HE *ventry;
    HE *kentry;
    SV *ksv;
    SV *vsv;
    
    /* store key as key */
    PERL_HASH(hash, key, strlen(key));
    ksv = newSViv((IV) &key);
    key_ptr = hv_store(hv, key, strlen(key), ksv, hash);
    kentry = get_entry((HvARRAY(hv))[hash & (I32) HvMAX(hv)],hash);

    /* store value as key */
    hash = 0;
    PERL_HASH(hash, v, strlen(v));
    vsv = newSViv((IV) &v);
    value_ptr = hv_store(hv, v, strlen(v), vsv, hash);
    ventry = get_entry((HvARRAY(hv))[hash & (I32) HvMAX(hv)],hash);

    /* set pointers of each */
    sv_setiv(ksv,(IV)HeKEY(ventry));
    sv_setiv(vsv,(IV)HeKEY(kentry));
    RETVAL = v;
OUTPUT:
    RETVAL

char * get(HV *hv, char *key)
CODE:
    HE *entry;
    U32 hash;

    PERL_HASH(hash, key, strlen(key));
    entry = get_entry((HvARRAY(hv))[hash & (I32) HvMAX(hv)],hash);
    RETVAL= (char*) SvIVX(HeVAL(entry));
OUTPUT:
    RETVAL