/*-
 * Copyright (c) 1999, 2000, 2001, 2002, 2003 Lev Walkin <vlm@lionet.info>.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * $Id: mimeword.c,v 1.7 2006/05/26 19:12:01 vlm Exp $
 */

#include <stdio.h>
#include <errno.h>

#ifdef	HAVE_CONFIG_H
#include "config.h"
#endif

#include <sf_mem.h>
#include <sf_core.h>
#include <sf_sed.h>
#include <sf_mime.h>

extern int _sf_in_mime_words;
char *(*_sf_convert_to_utf8)(const char *charset, char *body);

static char *
_sf_handler(svect *sl) {
	char *p;

	if(sl->count < 4) {
		sclear(sl);
		return NULL;
	}

	p = sl->list[3];
	if(ecq(sl->list[2], "Q")) {
		_sf_in_mime_words++;
		p = quoted_printable_decode(p, NULL);
		_sf_in_mime_words--;
	} else if(ecq(sl->list[2], "B")) {
		p = (char *)base64_decode(p, NULL);
	}

	if(_sf_convert_to_utf8) {
		static char *_np;
		char *np = _sf_convert_to_utf8(sl->list[1], p);
		if(np != p) {
			if(_np) free(_np);
			_np = np;
			p = np;
		}
	}

	sclear(sl);

	return p;
}

char *
mime_word_decode(const char *str, size_t *size) {
#ifndef	HAVE_REGCOMP
#warning	"mime_word_decode() will not function without regex."
	errno = EINVAL;
	return NULL;
#else
	static sed_t *se;
	static sbuf *sbs;
	sbuf *sb;

	if(se == NULL) {
		se = sed_compile(
			"s/=\\?([a-z0-9._-]+)\\?(.)\\?"
			"([^[:space:]\n\r\t?]+)"
			"\\?=[ \n\r\t]*/\\@/gei");
		if(se == NULL) {
			errno = EINVAL;
			return NULL;
		}
		sed_handler(se, _sf_handler);
	}

	if(sbs == NULL) {
		sbs = sbuf_init();
		if(sbs == NULL)
			/* ENOMEM? */
			return NULL;
	}

	/* Dynamic allocation */

	sb = sbuf_init();
	if(sb == NULL)
		/* ENOMEM? */
		return NULL;

	if(str == NULL) {
		if(sbuf_add(sb, "") == -1) {
			sbuf_free(sb);
			/* ENOMEM? */
			return NULL;
		}
		goto mwde;
	}

	if(countchar2(str, "=?") < 4) {
		sbuf_add(sb, str);
		goto mwde;
	}


	if(sbuf_add(sb, sed_exec(se, str)) == -1) {
		sbuf_free(sb);
		/* ENOMEM? */
		return NULL;
	}

mwde:
	if(sbs)
		sbuf_free(sbs);
	sbs = sb;
	if(size)
		*size = sbs->len;
	return sbs->buf;

#endif	/* HAVE_REGCOMP */
}