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

/* After 5.10, the CxLVAL macro was added. */
#ifndef CxLVAL
#  define CxLVAL(cx) cx->blk_sub.lval
#endif

#define MY_CXT_KEY "B::Utils::_guts" XS_VERSION

typedef struct {
    int		x_walkoptree_debug;	/* Flag for walkoptree debug hook */
    SV *	x_specialsv_list[7];
} my_cxt_t;

START_MY_CXT

/* Stolen from B.xs */

/* XXX: this really need to properly exported by the B module,
  possibly with custom .h retrieved by some extutil module for
  building, and we shall be able to simply reuse the public symbol
  from loaded module in run time. */

#ifdef PERL_OBJECT
#undef PL_op_name
#undef PL_opargs 
#undef PL_op_desc
#define PL_op_name (get_op_names())
#define PL_opargs (get_opargs())
#define PL_op_desc (get_op_descs())
#endif

/* duplicated from B.xs */
static char *svclassnames[] = {
    "B::NULL",
    "B::IV",
    "B::NV",
    "B::RV",
    "B::PV",
    "B::PVIV",
    "B::PVNV",
    "B::PVMG",
    "B::BM",
#if PERL_VERSION >= 9
    "B::GV",
#endif
    "B::PVLV",
    "B::AV",
    "B::HV",
    "B::CV",
#if PERL_VERSION <= 8
    "B::GV",
#endif
    "B::FM",
    "B::IO",
};

typedef enum {
    OPc_NULL,	/* 0 */
    OPc_BASEOP,	/* 1 */
    OPc_UNOP,	/* 2 */
    OPc_BINOP,	/* 3 */
    OPc_LOGOP,	/* 4 */
    OPc_LISTOP,	/* 5 */
    OPc_PMOP,	/* 6 */
    OPc_SVOP,	/* 7 */
    OPc_PADOP,	/* 8 */
    OPc_PVOP,	/* 9 */
    OPc_LOOP,	/* 10 */
    OPc_COP	/* 11 */
} opclass;

static char *opclassnames[] = {
    "B::NULL",
    "B::OP",
    "B::UNOP",
    "B::BINOP",
    "B::LOGOP",
    "B::LISTOP",
    "B::PMOP",
    "B::SVOP",
    "B::PADOP",
    "B::PVOP",
    "B::LOOP",
    "B::COP"	
};

static opclass
cc_opclass(pTHX_ const OP *o)
{
    if (!o)
	return OPc_NULL;

    if (o->op_type == 0)
	return (o->op_flags & OPf_KIDS) ? OPc_UNOP : OPc_BASEOP;

    if (o->op_type == OP_SASSIGN)
	return ((o->op_private & OPpASSIGN_BACKWARDS) ? OPc_UNOP : OPc_BINOP);

#ifdef USE_ITHREADS
    if (o->op_type == OP_GV || o->op_type == OP_GVSV ||
	o->op_type == OP_AELEMFAST || o->op_type == OP_RCATLINE)
	return OPc_PADOP;
#endif

    switch (PL_opargs[o->op_type] & OA_CLASS_MASK) {
    case OA_BASEOP:
	return OPc_BASEOP;

    case OA_UNOP:
	return OPc_UNOP;

    case OA_BINOP:
	return OPc_BINOP;

    case OA_LOGOP:
	return OPc_LOGOP;

    case OA_LISTOP:
	return OPc_LISTOP;

    case OA_PMOP:
	return OPc_PMOP;

    case OA_SVOP:
	return OPc_SVOP;

    case OA_PADOP:
	return OPc_PADOP;

    case OA_PVOP_OR_SVOP:
        /*
         * Character translations (tr///) are usually a PVOP, keeping a 
         * pointer to a table of shorts used to look up translations.
         * Under utf8, however, a simple table isn't practical; instead,
         * the OP is an SVOP, and the SV is a reference to a swash
         * (i.e., an RV pointing to an HV).
         */
	return (o->op_private & (OPpTRANS_TO_UTF|OPpTRANS_FROM_UTF))
		? OPc_SVOP : OPc_PVOP;

    case OA_LOOP:
	return OPc_LOOP;

    case OA_COP:
	return OPc_COP;

    case OA_BASEOP_OR_UNOP:
	/*
	 * UNI(OP_foo) in toke.c returns token UNI or FUNC1 depending on
	 * whether parens were seen. perly.y uses OPf_SPECIAL to
	 * signal whether a BASEOP had empty parens or none.
	 * Some other UNOPs are created later, though, so the best
	 * test is OPf_KIDS, which is set in newUNOP.
	 */
	return (o->op_flags & OPf_KIDS) ? OPc_UNOP : OPc_BASEOP;

    case OA_FILESTATOP:
	/*
	 * The file stat OPs are created via UNI(OP_foo) in toke.c but use
	 * the OPf_REF flag to distinguish between OP types instead of the
	 * usual OPf_SPECIAL flag. As usual, if OPf_KIDS is set, then we
	 * return OPc_UNOP so that walkoptree can find our children. If
	 * OPf_KIDS is not set then we check OPf_REF. Without OPf_REF set
	 * (no argument to the operator) it's an OP; with OPf_REF set it's
	 * an SVOP (and op_sv is the GV for the filehandle argument).
	 */
	return ((o->op_flags & OPf_KIDS) ? OPc_UNOP :
#ifdef USE_ITHREADS
		(o->op_flags & OPf_REF) ? OPc_PADOP : OPc_BASEOP);
#else
		(o->op_flags & OPf_REF) ? OPc_SVOP : OPc_BASEOP);
#endif
    case OA_LOOPEXOP:
	/*
	 * next, last, redo, dump and goto use OPf_SPECIAL to indicate that a
	 * label was omitted (in which case it's a BASEOP) or else a term was
	 * seen. In this last case, all except goto are definitely PVOP but
	 * goto is either a PVOP (with an ordinary constant label), an UNOP
	 * with OPf_STACKED (with a non-constant non-sub) or an UNOP for
	 * OP_REFGEN (with goto &sub) in which case OPf_STACKED also seems to
	 * get set.
	 */
	if (o->op_flags & OPf_STACKED)
	    return OPc_UNOP;
	else if (o->op_flags & OPf_SPECIAL)
	    return OPc_BASEOP;
	else
	    return OPc_PVOP;
    }
    warn("can't determine class of operator %s, assuming BASEOP\n",
	 PL_op_name[o->op_type]);
    return OPc_BASEOP;
}

char *
BUtils_cc_opclassname(pTHX_ const OP *o)
{
    return opclassnames[cc_opclass(aTHX_ o)];
}

I32
BUtils_op_name_to_num(SV *name)
{
    dTHX;
    char const *s;
    char *wanted = SvPV_nolen(name);
    int i =0;
    int topop = OP_max;

#ifdef PERL_CUSTOM_OPS
    topop--;
#endif

    if (SvIOK(name) && SvIV(name) >= 0 && SvIV(name) < topop)
        return SvIV(name);

    for (s = PL_op_name[i]; s; s = PL_op_name[++i]) {
        if (strEQ(s, wanted))
            return i;
    }
#ifdef PERL_CUSTOM_OPS
    if (PL_custom_op_names) {
        HE* ent;
        SV* value;
        /* This is sort of a hv_exists, backwards */
        (void)hv_iterinit(PL_custom_op_names);
        while ((ent = hv_iternext(PL_custom_op_names))) {
            if (strEQ(SvPV_nolen(hv_iterval(PL_custom_op_names,ent)),wanted))
                return OP_CUSTOM;
        }
    }
#endif

    croak("No such op \"%s\"", SvPV_nolen(name));

    return -1;
}

SV *
BUtils_make_sv_object(pTHX_ SV *arg, SV *sv)
{
    char *type = 0;
    IV iv;
    dMY_CXT;

    if (!type) {
	type = svclassnames[SvTYPE(sv)];
	iv = PTR2IV(sv);
    }
    sv_setiv(newSVrv(arg, type), iv);
    return arg;
}

MODULE = B::Utils           PACKAGE = B::Utils