/* Unified diffs backend */
/* $Id: unidiff.c,v 1.1 2003/09/10 19:32:27 pasky Exp $ */

/*
 * Copyright (c) 2003  Petr Baudis.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   * Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *   * 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.
 *   * Neither the name of the author nor the names of the product's
 *     contributors may be used to endorse or promote products
 *     derived from this software without specific prior written
 *     permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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.
 */

#define _GNU_SOURCE /* for the asprintf() hack */

#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <librev/data_text.h>
#include <librev/delta.h>
#include <librev/librev.h>
#include <librev/list.h>


char *
rev_delta_text_export_unidiff (struct rev_delta_text *delta_text)
{
	/* FIXME */
	char str[65536];
	struct rev_delta_text_fragment *fragment;
	int drift = 0;

	assert (delta_text);

	/* FIXME: Output of this is *really* ugly. --pasky */

	/* This is just a quick hack to make it do something. It is not nice,
	 * even remotely. */

	rev_list_foreach (delta_text->fragments, fragment) {
		int line = rev_delta_text_fragment_get_lineno (fragment);
		enum rev_delta_text_fragment_type type =
			rev_delta_text_fragment_get_type (fragment);

		if (type == DFT_ADD) drift++; else drift--;

		snprintf(str, 65536, "%s@@ -%d,1 +%d, 1 @@\n%c%s\n", str,
				line, line - drift,
				(type == DFT_ADD ? '+' : '-'),
				*rev_delta_text_fragment_get_line (fragment));
	} rev_list_foreach_end;

	return strdup (str);
}