/*
 *  upkg: tool for manipulating Unreal Tournament packages.
 *  Copyright © 2009-2011, 2019 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 3 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, see <http://www.gnu.org/licenses/>.
 */

#include <stdio.h>
#include <stdlib.h>
#include <libmodplug/modplug.h>
#include "modplug-types.h"

#include "music-module.h"
#include "upkg.h"

struct music_mod {
	ModPlugFile *f;
	size_t len, alloc;
	unsigned char buf[];
};

#define BUF_INIT_SIZE 65536

int music_mod_init(void)
{
	ModPlug_Settings settings = {
		.mFlags          = MODPLUG_ENABLE_OVERSAMPLING,
		.mChannels       = 2,
		.mFrequency      = 44100,
		.mResamplingMode = MODPLUG_RESAMPLE_SPLINE,
		.mLoopCount      = -1,
	};

	ModPlug_SetSettings(&settings);
	return 0;
}

void music_mod_exit(void)
{
}

static struct music_mod *readfile(struct upkg_file *f)
{
	struct music_mod *m = malloc(sizeof *m + BUF_INIT_SIZE);
	if (!m) return NULL;
	*m = (struct music_mod) {
		.alloc = BUF_INIT_SIZE
	};

	while (1) {
		struct music_mod *tmp;
		size_t sz = m->alloc - m->len;
		
		m->len += upkg_export_read(f, m->buf + m->len, sz);
		if (m->alloc != m->len) {
			if (f->eof) {
				tmp = realloc(m, sizeof *m + m->len);
				return tmp ? tmp : m;
			}

			break;
		}

		tmp = realloc(m, sizeof *m + 2*m->alloc);
		if (!tmp)
			break;
		m = tmp;
		m->alloc *= 2;
	}

	free(m);
	return NULL;
}

struct music_mod *music_mod_open(struct upkg_file *f)
{
	struct music_mod *m = readfile(f);
	if (!m) return NULL;

	m->f = ModPlug_Load(m->buf, m->len);
	if (!m->f) {
		free(m);
		return NULL;
	}

	return m;
}

int music_mod_dump(struct music_mod *m, FILE *of)
{
	if (fwrite(m->buf, m->len, 1, of) != 1)
		return -1;
	return 0;
}

void music_mod_close(struct music_mod *m)
{
	ModPlug_Unload(m->f);
	free(m);
}

const char *music_mod_type(struct music_mod *m)
{
	int type = ModPlug_GetModuleType(m->f);

	if (type & MOD_TYPE_MOD)
		return "mod";
	if (type & MOD_TYPE_S3M)
		return "s3m";
	if (type & MOD_TYPE_XM)
		return "xm";
	if (type & MOD_TYPE_IT)
		return "it";
	return "unknown";
}