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

#include "ppport.h"

#include "hook_op_check_smartmatch.h"

STATIC OP*
smartmatch_cb(pTHX_ OP *o, void *user_data)
{
    OP *left, *right, *cb_op, *list, *new;
    SV **cb;

    cb = hv_fetchs(GvHV(PL_hintgv), "smartmatch_cb", 0);
    if (!cb) {
        return o;
    }

    left = cBINOPo->op_first;
    right = left->op_sibling;

    o->op_flags &= ~OPf_KIDS;
    op_free(o);

    cb_op = newCVREF(0, newSVOP(OP_CONST, 0, newSVsv(*cb)));
    list = newLISTOP(OP_LIST, 0, left, right);
    new = newUNOP(OP_ENTERSUB, OPf_STACKED,
                  op_append_elem(OP_LIST, list, cb_op));

    return new;
}

UV
hook_op_check_smartmatch()
{
    return hook_op_check(OP_SMARTMATCH, smartmatch_cb, NULL);
}

MODULE = smartmatch  PACKAGE = smartmatch

PROTOTYPES: DISABLE

BOOT:
    hook_op_check_smartmatch();

void
register (cb)
    SV *cb;
    CODE:
        if (!SvROK(cb) || SvTYPE(SvRV(cb)) != SVt_PVCV) {
            croak("not a coderef");
        }

        PL_hints |= HINT_LOCALIZE_HH;
        gv_HVadd(PL_hintgv);

        SvREFCNT_inc(cb);
        if (!hv_stores(GvHV(PL_hintgv), "smartmatch_cb", cb)) {
            SvREFCNT_dec(cb);
            croak("couldn't store the callback");
        }

void
unregister ()
    CODE:
        PL_hints |= HINT_LOCALIZE_HH;
        gv_HVadd(PL_hintgv);

        hv_delete(GvHV(PL_hintgv), "smartmatch_cb", 13, G_DISCARD);