#include "wc.h"
#include "big5.h"
#include "search.h"
#include "wtf.h"
#ifdef USE_UNICODE
#include "ucs.h"
#endif

#define C0 WC_BIG5_MAP_C0
#define GL WC_BIG5_MAP_GL
#define C1 WC_BIG5_MAP_C1
#define LB WC_BIG5_MAP_LB
#define UB WC_BIG5_MAP_UB

wc_uint8 WC_BIG5_MAP[ 0x100 ] = {
    C0, C0, C0, C0, C0, C0, C0, C0, C0, C0, C0, C0, C0, C0, C0, C0,
    C0, C0, C0, C0, C0, C0, C0, C0, C0, C0, C0, C0, C0, C0, C0, C0,
    GL, GL, GL, GL, GL, GL, GL, GL, GL, GL, GL, GL, GL, GL, GL, GL,
    GL, GL, GL, GL, GL, GL, GL, GL, GL, GL, GL, GL, GL, GL, GL, GL,
    LB, LB, LB, LB, LB, LB, LB, LB, LB, LB, LB, LB, LB, LB, LB, LB,
    LB, LB, LB, LB, LB, LB, LB, LB, LB, LB, LB, LB, LB, LB, LB, LB,
    LB, LB, LB, LB, LB, LB, LB, LB, LB, LB, LB, LB, LB, LB, LB, LB,
    LB, LB, LB, LB, LB, LB, LB, LB, LB, LB, LB, LB, LB, LB, LB, C0,

    C1, C1, C1, C1, C1, C1, C1, C1, C1, C1, C1, C1, C1, C1, C1, C1,
    C1, C1, C1, C1, C1, C1, C1, C1, C1, C1, C1, C1, C1, C1, C1, C1,
    C1, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB,
    UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB,
    UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB,
    UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB,
    UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB,
    UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, UB, C1,
};

wc_wchar_t
wc_big5_to_cs94w(wc_wchar_t cc)
{
    cc.code = WC_BIG5_N(cc.code);
    if (cc.code < WC_C_BIG5_2_BASE)
	cc.ccs = WC_CCS_BIG5_1;
    else {
	cc.ccs = WC_CCS_BIG5_2;
	cc.code -= WC_C_BIG5_2_BASE;
    }
    cc.code = WC_N_CS94W(cc.code);
    return cc;
}

wc_wchar_t
wc_cs94w_to_big5(wc_wchar_t cc)
{
    cc.code = WC_CS94W_N(cc.code);
    if (cc.ccs == WC_CCS_BIG5_2)
	cc.code += WC_C_BIG5_2_BASE;
    cc.code = WC_N_BIG5(cc.code);
    cc.ccs = WC_CCS_BIG5;
    return cc;
}

Str
wc_conv_from_big5(Str is, wc_ces ces)
{
    Str os;
    wc_uchar *sp = (wc_uchar *)is->ptr;
    wc_uchar *ep = sp + is->length;
    wc_uchar *p;
    int state = WC_BIG5_NOSTATE;

    for (p = sp; p < ep && *p < 0x80; p++) 
	;
    if (p == ep)
	return is;
    os = Strnew_size(is->length);
    if (p > sp)
	Strcat_charp_n(os, (char *)is->ptr, (int)(p - sp));

    for (; p < ep; p++) {
	switch (state) {
	case WC_BIG5_NOSTATE:
	    switch (WC_BIG5_MAP[*p]) {
	    case UB:
		state = WC_BIG5_MBYTE1;
		break;
	    case C1:
		wtf_push_unknown(os, p, 1);
		break;
	    default:
		Strcat_char(os, (char)*p);
		break;
	    }
	    break;
	case WC_BIG5_MBYTE1:
	    if (WC_BIG5_MAP[*p] & LB)
		wtf_push(os, WC_CCS_BIG5, ((wc_uint32)*(p-1) << 8) | *p);
	    else
		wtf_push_unknown(os, p-1, 2);
	    state = WC_BIG5_NOSTATE;
	    break;
	}
    }
    switch (state) {
    case WC_BIG5_MBYTE1:
	wtf_push_unknown(os, p-1, 1);
	break;
    }
    return os;
}

void
wc_push_to_big5(Str os, wc_wchar_t cc, wc_status *st)
{
  while (1) {
    switch (cc.ccs) {
    case WC_CCS_US_ASCII:
	Strcat_char(os, (char)cc.code);
	return;
    case WC_CCS_BIG5_1:
    case WC_CCS_BIG5_2:
	cc = wc_cs94w_to_big5(cc);
    case WC_CCS_BIG5:
	Strcat_char(os, (char)(cc.code >> 8));
	Strcat_char(os, (char)(cc.code & 0xff));
	return;
    case WC_CCS_UNKNOWN_W:
	if (!WcOption.no_replace)
	    Strcat_charp(os, WC_REPLACE_W);
	return;
    case WC_CCS_UNKNOWN:
	if (!WcOption.no_replace)
	    Strcat_charp(os, WC_REPLACE);
	return;
    default:
#ifdef USE_UNICODE
	if (WcOption.ucs_conv)
	    cc = wc_any_to_any_ces(cc, st);
	else
#endif
	    cc.ccs = WC_CCS_IS_WIDE(cc.ccs) ? WC_CCS_UNKNOWN_W : WC_CCS_UNKNOWN;
	continue;
    }
  }
}

Str
wc_char_conv_from_big5(wc_uchar c, wc_status *st)
{
    static Str os;
    static wc_uchar big5u;

    if (st->state == -1) {
	st->state = WC_BIG5_NOSTATE;
	os = Strnew_size(8);
    }

    switch (st->state) {
    case WC_BIG5_NOSTATE:
	switch (WC_BIG5_MAP[c]) {
	case UB:
	    big5u = c;
	    st->state = WC_BIG5_MBYTE1;
	    return NULL;
	case C1:
	    break;
	default:
	    Strcat_char(os, (char)c);
	    break;
	}
	break;
    case WC_BIG5_MBYTE1:
	if (WC_BIG5_MAP[c] & LB)
	    wtf_push(os, WC_CCS_BIG5, ((wc_uint32)big5u << 8) | c);
	break;
    }
    st->state = -1;
    return os;
}