/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */


#include <stdlib.h>
#include <errno.h>
#include <euc.h>
#include "japanese.h"
#include "jfp_iconv_unicode.h"

#define JFP_J2U_ICONV_X0213
#include "jfp_jis_to_ucs2.h"

struct _icv_state {
        int     _st_cset;
};

void *
_icv_open(void)
{
        void                    *cd;
        struct _icv_state       *st;

        cd = _icv_open_unicode(sizeof (struct _icv_state));

        if (cd != NULL) {
                st = (struct _icv_state *)(_icv_get_ext(cd));
                st->_st_cset = CS_0;
        }

        return (cd);
}

void
_icv_close(void *cd)
{
        _icv_close_unicode(cd);
        return;
}

size_t
_icv_iconv(void *cd, char **inbuf, size_t *inbytesleft,
                                char **outbuf, size_t *outbytesleft)
{
        unsigned int    u32;            /* UTF-32 */
        unsigned short  e16;            /* 16-bit EUC */
        unsigned char   ic1, ic2;       /* bytes in a char or an esc seq */
        unsigned char   ic3, ic4;       /* bytes in an esc seq */
        size_t          rv = (size_t)0; /* return value of this function */
        struct _icv_state       *st;

        unsigned char   *ip;
        size_t          ileft;
        char            *op;
        size_t          oleft;

        st = (struct _icv_state *)(_icv_get_ext(cd));

        /*
         * If inbuf and/or *inbuf are NULL, reset conversion descriptor
         * and put escape sequence if needed.
         */
        if ((inbuf == NULL) || (*inbuf == NULL)) {
                st->_st_cset = CS_0;
                _icv_reset_unicode(cd);
                return ((size_t)0);
        }

        ip = (unsigned char *)*inbuf;
        ileft = *inbytesleft;
        op = *outbuf;
        oleft = *outbytesleft;

        while (ileft != 0) {
                NGET(ic1, "never fail here"); /* get 1st byte */

                if (ic1 == ESC) { /* Escape */
                        NGET(ic2, "ESC-2");
                        switch (ic2) {
                        case 0x24: /* $ */
                                NGET(ic3, "ESC$-3");
                                switch (ic3) {
                                case 0x28: /* $( */
                                        NGET(ic4, "ESC$(-4");
                                        switch (ic4) {
                                        case 0x4f: /* 24-28-4F ESC$(O */
                                                st->_st_cset = CS_1;
                                                break;
                                        case 0x50: /* 24-28-50 ESC$(P */
                                                st->_st_cset = CS_3;
                                                break;
                                        case 0x51: /* 24-28-51 ESC$(Q */
                                                st->_st_cset = CS_1;
                                                break;
                                        default:
                                                RETERROR(EILSEQ,
                                                        "Unknown ESC$(?");
                                        }
                                        break;
                                case 0x42: /* 24-42 ESC$B */
                                        st->_st_cset = CS_1;
                                        break;
                                default:
                                        RETERROR(EILSEQ, "Unknown ESC$?");
                                }
                                break;
                        case 0x28: /* ( */
                                NGET(ic3, "ESC(-3");
                                switch (ic3) {
                                case 0x42: /* 28-42 ESC(B */
                                        st->_st_cset = CS_0;
                                        break;
                                default:
                                        RETERROR(EILSEQ, "Unknown ESC(?");
                                }
                                break;
                        default:
                                RETERROR(EILSEQ, "Unknown ESC?");
                        }
                } else if (st->_st_cset == CS_0) { /* IRV */
                        if ((ic1 == 0x0e) || (ic1 == 0x0f) || (ic1 > 0x7f)) {
                                RETERROR(EILSEQ, "IRV-1")
                        }
                        u32 = (unsigned int)_jfp_tbl_jisx0201roman_to_ucs2[ic1];
                        PUTU(u32, "IRV");
                } else if (st->_st_cset == CS_1) { /* Plane 1 */
                        if ((ic1 < 0x21) || (ic1 > 0x7e)) {
                                RETERROR(EILSEQ, "PLANE1-1")
                        }
                        NGET(ic2, "PLANE1-2");
                        if ((ic2 < 0x21) || (ic2 > 0x7e)) {
                                RETERROR(EILSEQ, "PLANE1-2")
                        }
                        e16 = ((ic1 << 8) | ic2) | 0x8080;
                        u32 = (unsigned int)_jfp_tbl_jisx0208_to_ucs2[
                                (ic1 - 0x21) * 94 + (ic2 - 0x21)];
                        if (IFHISUR(u32)) {
                                u32 = _jfp_lookup_x0213_nonbmp(e16, u32);
                                PUTU(u32, "PLANE1->NONBMP");
                        } else if (u32 == 0xffff) {
                                /* need to compose */
                                unsigned int    u32_2;
                                u32 = _jfp_lookup_x0213_compose(e16, &u32_2);
                                PUTU(u32, "PLANE1->CP1");
                                PUTU(u32_2, "PLANE1->CP2");
                        } else {
                                PUTU(u32, "PLANE1->BMP");
                        }
                } else if (st->_st_cset == CS_3) { /* Plane 2 */
                        if ((ic1 < 0x21) || (ic1 > 0x7e)) {
                                RETERROR(EILSEQ, "PLANE2-1")
                        }
                        NGET(ic2, "PLANE2-2");
                        if ((ic2 < 0x21) || (ic2 > 0x7e)) {
                                RETERROR(EILSEQ, "PLANE2-2")
                        }
                        e16 = ((ic1 << 8) | ic2) | 0x8000;
                        u32 = (unsigned int)_jfp_tbl_jisx0213p2_to_ucs2[
                                (ic1 - 0x21) * 94 + (ic2 - 0x21)];
                        if (IFHISUR(u32)) {
                                u32 = _jfp_lookup_x0213_nonbmp(e16, u32);
                                PUTU(u32, "PLANE2->NONBMP");
                        } else {
                                PUTU(u32, "PLANE2->BMP");
                        }
                }

                /*
                 * One character successfully converted so update
                 * values outside of this function's stack.
                 */
                *inbuf = (char *)ip;
                *inbytesleft = ileft;
                *outbuf = op;
                *outbytesleft = oleft;
        }

ret:
        DEBUGPRINTERROR

        /*
         * Return value for successful return is not defined by XPG
         * so return same as *inbytesleft as existing codes do.
         */
        return ((rv == (size_t)-1) ? rv : *inbytesleft);
}