/*
 * 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_U2E_ICONV_X0213
#include "jfp_ucs2_to_euc16.h"

#define DEF_SINGLE      '?'

#define CS0_SEQ2        0x28    /* ( */
#define CS0_SEQ3        0x42    /* B */

#define CS1_SEQ2        0x24    /* $ */
#define CS1_SEQ3        0x28    /* ( */
#define CS1_SEQ4        0x51    /* Q */

#define CS3_SEQ2        0x24    /* $ */
#define CS3_SEQ3        0x28    /* ( */
#define CS3_SEQ4        0x50    /* P */

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   ic;
        size_t          rv = (size_t)0;

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

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

        /*
         * If inbuf and/or *inbuf are NULL, reset conversion descriptor
         * and put escape sequence if needed.
         */
        if ((inbuf == NULL) || (*inbuf == NULL)) {
                if (st->_st_cset != CS_0) {
                        if ((outbuf != NULL) && (*outbuf != NULL)
                                        && (outbytesleft != NULL)) {
                                op = (char *)*outbuf;
                                oleft = *outbytesleft;
                                NPUT(ESC, "RESET-SEQ-ESC");
                                NPUT(CS0_SEQ2, "RESET-SEQ2");
                                NPUT(CS0_SEQ3, "RESET-SEQ3");
                                *outbuf = (char *)op;
                                *outbytesleft = oleft;
                        }
                        st->_st_cset = CS_0;
                        _icv_reset_unicode(cd);
                }
                return ((size_t)0);
        }

        cset = st->_st_cset;

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

        while (ileft != 0) {
                GETU(&u32)

                e16 = _jfp_u32_to_euc16(u32);

                switch (e16 & 0x8080) {
                case 0x0000:    /* CS0 */
                        if (cset != CS_0) {
                                NPUT(ESC, "CS0-SEQ-ESC");
                                NPUT(CS0_SEQ2, "CS0-SEQ2");
                                NPUT(CS0_SEQ3, "CS0-SEQ3");
                                cset = CS_0;
                        }
                        ic = (unsigned char)e16;
                        NPUT(ic, "CS0");
                        break;
                case 0x8080:    /* CS1 */
                        if (cset != CS_1) {
                                NPUT(ESC, "CS1-SEQ-ESC");
                                NPUT(CS1_SEQ2, "CS1-SEQ2");
                                NPUT(CS1_SEQ3, "CS1-SEQ3");
                                NPUT(CS1_SEQ4, "CS1-SEQ4");
                                cset = CS_1;
                        }
                        ic = (unsigned char)((e16 >> 8) & 0x7f);
                        NPUT(ic, "CS1-1");
                        ic = (unsigned char)(e16 & 0x7f);
                        NPUT(ic, "CS1-2");
                        break;
                case 0x0080:    /* CS2 */
                        if (cset != CS_0) {
                                NPUT(ESC, "CS2-REPL-SEQ-ESC");
                                NPUT(CS0_SEQ2, "CS2-REPL-SEQ2");
                                NPUT(CS0_SEQ3, "CS2-REPL-SEQ3");
                                cset = CS_0;
                        }
                        ic = DEF_SINGLE;
                        NPUT(ic, "CS2-REPL");
                        break;
                case 0x8000:    /* CS3 */
                        if (cset != CS_3) {
                                NPUT(ESC, "CS3-SEQ-ESC");
                                NPUT(CS3_SEQ2, "CS3-SEQ2");
                                NPUT(CS3_SEQ3, "CS3-SEQ3");
                                NPUT(CS3_SEQ4, "CS3-SEQ4");
                                cset = CS_3;
                        }
                        ic = (unsigned char)((e16 >> 8) & 0x7f);
                        NPUT(ic, "CS3-1");
                        ic = (unsigned char)(e16 & 0x7f);
                        NPUT(ic, "CS3-2");
                        break;
                }

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

                st->_st_cset = cset;
        }

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);
}