/* the Music Player Daemon (MPD)
 * Copyright (C) 2003-2007 by Warren Dukes (warren.dukes@gmail.com)
 * This project's homepage is: http://www.musicpd.org
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include "state_file.h"
#include "audio.h"
#include "playlist.h"
#include "volume.h"

#include <glib.h>
#include <string.h>
#include <errno.h>

#undef G_LOG_DOMAIN
#define G_LOG_DOMAIN "state_file"

static struct _sf_cb {
	void (*reader)(FILE *);
	void (*writer)(FILE *);
} sf_callbacks [] = {
	{ read_sw_volume_state, save_sw_volume_state },
	{ readAudioDevicesState, saveAudioDevicesState },
	{ readPlaylistState, savePlaylistState },
};

static char *state_file_path;

void write_state_file(void)
{
	unsigned int i;
	FILE *fp;

	if (state_file_path == NULL)
		return;

	fp = fopen(state_file_path, "w");
	if (G_UNLIKELY(!fp)) {
		g_warning("failed to create %s: %s",
			  state_file_path, strerror(errno));
		return;
	}

	for (i = 0; i < G_N_ELEMENTS(sf_callbacks); i++)
		sf_callbacks[i].writer(fp);

	while(fclose(fp) && errno == EINTR) /* nothing */;
}

static void
state_file_read(void)
{
	unsigned int i;
	FILE *fp;

	assert(state_file_path != NULL);

	fp = fopen(state_file_path, "r");
	if (G_UNLIKELY(!fp)) {
		g_warning("failed to open %s: %s",
			  state_file_path, strerror(errno));
		return;
	}
	for (i = 0; i < G_N_ELEMENTS(sf_callbacks); i++) {
		sf_callbacks[i].reader(fp);
		rewind(fp);
	}

	while(fclose(fp) && errno == EINTR) /* nothing */;
}

void
state_file_init(const char *path)
{
	assert(state_file_path == NULL);

	if (path == NULL)
		return;

	state_file_path = g_strdup(path);
	state_file_read();
}

void
state_file_finish(void)
{
	if (state_file_path != NULL)
		write_state_file();

	g_free(state_file_path);
}