/*
 *  upkg: tool for manipulating Unreal Tournament packages.
 *  Copyright (C) 2009 Nick Bowler
 *
 *  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 <stdio.h>
#include <string.h>
#include <glib-object.h>

#include "exportable.h"
#include "loadable.h"
#include "uobject.h"
#include "music-module.h"
#include "music.h"
#include "upkg.h"

#define MUSIC_GET_PRIV(o) \
	G_TYPE_INSTANCE_GET_PRIVATE(o, ENGINE_MUSIC_TYPE, struct music_priv)

struct music_priv {
	struct upkg_file *f;
	struct music_mod *mod;
	unsigned loaded;
};

static void exportable_init(UObjectExportable *);
static void loadable_init(UObjectLoadable *);

G_DEFINE_DYNAMIC_TYPE_EXTENDED(EngineMusic, engine_music, U_OBJECT_TYPE, 0,
	G_IMPLEMENT_INTERFACE(U_OBJECT_TYPE_EXPORTABLE, exportable_init)
	G_IMPLEMENT_INTERFACE(U_OBJECT_TYPE_LOADABLE, loadable_init)
);

static int load(GObject *o)
{
	struct music_priv *priv = MUSIC_GET_PRIV(o);

	if (!priv->loaded) {
		g_return_val_if_fail(priv->f != NULL, -1);

		if (upkg_export_seek(priv->f, 0, SEEK_SET) != 0) {
			return -1;
		}

		priv->mod = music_mod_open(priv->f);
		if (!priv->mod) {
			return -1;
		}
	}

	priv->loaded++;
	return 0;
}

static void unload(GObject *o)
{
	struct music_priv *priv = MUSIC_GET_PRIV(o);
	g_return_if_fail(priv->loaded > 0);

	if (--priv->loaded == 0) {
		music_mod_close(priv->mod);
	}
}

static int export(GObject *o, FILE *f)
{
	struct music_priv *priv = MUSIC_GET_PRIV(o);
	int rc;

	if (load(o) != 0)
		return -1;

	rc = music_mod_dump(priv->mod, f);

	unload(o);

	return rc;
}

static int export_name(GObject *o, char *buf, size_t n)
{
	struct music_priv *priv = MUSIC_GET_PRIV(o);
	const char *type;
	int rc;

	if (load(o) != 0) {
		if (n > 0) *buf = 0;
		return 0;
	}

	type = music_mod_type(priv->mod);
	rc = snprintf(buf, n, "%s.%s", priv->f->name, type);

	unload(o);

	return rc;
}

static void exportable_init(UObjectExportable *e)
{
	e->export      = export;
	e->export_name = export_name;
}

static void loadable_init(UObjectLoadable *l)
{
	l->load   = load;
	l->unload = unload;
}

static int deserialize(UObject *o, struct upkg_file *f)
{
	struct music_priv *priv = MUSIC_GET_PRIV(o);
	size_t rc, pos = 0, buflen;
	unsigned char buf[32];
	long size;

	U_OBJECT_CLASS(engine_music_parent_class)->deserialize(o, f);

	buflen = upkg_export_read(f, buf, sizeof buf);

	/* Random field #1 */
	if (buflen - pos < 1)
		return -1;
	pos += 1;

	if (f->pkg->version > 61) {
		/* Random field #2 */
		if (buflen - pos < 4)
			return -1;
		pos += 4;
	}

	rc = upkg_decode_index(&size, buf+pos, buflen-pos);
	if (rc == 0 || size < 0)
		return -1;
	pos += rc;

	f->base += pos;
	f->len   = size;
	upkg_export_seek(f, 0, SEEK_SET);
	priv->f = f;

	return 0;
}

void music_register(GTypeModule *m)
{
	engine_music_register_type(m);
}

static void engine_music_init(EngineMusic *m)
{
	struct music_priv *priv = MUSIC_GET_PRIV(m);
	*priv = (struct music_priv){0};
}

static void engine_music_finalize(GObject *o)
{
	struct music_priv *priv = MUSIC_GET_PRIV(o);

	if (priv->loaded >= 1) {
		priv->loaded = 1;
		unload(o);
	}

	G_OBJECT_CLASS(engine_music_parent_class)->finalize(o);
}

static void engine_music_class_init(EngineMusicClass *class)
{
	UObjectClass *uo = U_OBJECT_CLASS(class);
	GObjectClass *go = G_OBJECT_CLASS(class);
	g_type_class_add_private(class, sizeof (struct music_priv));

	uo->deserialize = deserialize;
	go->finalize    = engine_music_finalize;

	music_mod_init();
}

static void engine_music_class_finalize(EngineMusicClass *class)
{
	music_mod_exit();
}