/* ScummVM - Scumm Interpreter
 * Copyright (C) 2006 The ScummVM project
 *
 * cinE Engine is (C) 2004-2005 by CinE Team
 *
 * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * $URL$
 * $Id$
 *
 */

#include "common/stdafx.h"
#include "common/endian.h"
#include "common/system.h"

#include "cine/cine.h"
#include "cine/sfx_player.h"
#include "cine/sound_driver.h"
#include "cine/unpack.h"
#include "cine/various.h"

namespace Cine {

SfxPlayer::SfxPlayer(SoundDriver *driver)
	: _playing(false), _driver(driver) {
	memset(_instrumentsData, 0, sizeof(_instrumentsData));
	_sfxData = NULL;
	_fadeOutCounter = 0;
	_driver->setUpdateCallback(updateCallback, this);
}

SfxPlayer::~SfxPlayer() {
	_driver->setUpdateCallback(NULL, NULL);
	if (_playing) {
		stop();
	}
}

bool SfxPlayer::load(const char *song) {
	debug(9, "SfxPlayer::load('%s')", song);
	
	/* stop (w/ fade out) the previous song */
	while (_fadeOutCounter != 0 && _fadeOutCounter < 100) {
		g_system->delayMillis(50);
	}
	_fadeOutCounter = 0;

	if (_playing) {
		stop();
	}

	/* like the original PC version, skip introduction song (file doesn't exist) */
	if (gameType == Cine::GID_OS && strncmp(song, "INTRO", 5) == 0) {
		return 0;
	}
		
	_sfxData = snd_loadBasesonEntry(song);
	if (!_sfxData) {
		warning("Unable to load soundfx module '%s'", song);
		return 0;
	}

	for (int i = 0; i < NUM_INSTRUMENTS; ++i) {
		_instrumentsData[i] = NULL;
		
		char instrument[13];
		memcpy(instrument, _sfxData + 20 + i * 30, 12);
		instrument[12] = '\0';
		
		if (strlen(instrument) != 0) {
			char *dot = strrchr(instrument, '.');
			if (dot) {
				*dot = '\0';
			}
			strcat(instrument, _driver->getInstrumentExtension());
			_instrumentsData[i] = snd_loadBasesonEntry(instrument);
			if (!_instrumentsData[i]) {
				warning("Unable to load soundfx instrument '%s'", instrument);
			}
		}
	}
	return 1;
}

void SfxPlayer::play() {
	debug(9, "SfxPlayer::play()");
	if (_sfxData) {
		for (int i = 0; i < NUM_CHANNELS; ++i) {
			_instrumentsChannelTable[i] = -1;
		}
		_currentPos = 0;
		_currentOrder = 0;
		_numOrders = _sfxData[470];
		_eventsDelay = (252 - _sfxData[471]) * 50 / 1060;
		_updateTicksCounter = 0;
		_playing = true;
	}
}

void SfxPlayer::stop() {
	_fadeOutCounter = 0;
	_playing = false;
	for (int i = 0; i < NUM_CHANNELS; ++i) {
		_driver->stopChannel(i);
	}
	_driver->stopSound();
	unload();
}

void SfxPlayer::fadeOut() {
	if (_playing) {
		_fadeOutCounter = 1;
		_playing = false;
	}
}

void SfxPlayer::updateCallback(void *ref) {
	((SfxPlayer *)ref)->update();
}

void SfxPlayer::update() {
	if (_playing || (_fadeOutCounter != 0 && _fadeOutCounter < 100)) {
		++_updateTicksCounter;
		if (_updateTicksCounter > _eventsDelay) {
			handleEvents();
			_updateTicksCounter = 0;
		}
	}
}

void SfxPlayer::handleEvents() {
	const byte *patternData = _sfxData + 600;
	const byte *orderTable = _sfxData + 472;
	uint16 patternNum = orderTable[_currentOrder] * 1024;

	for (int i = 0; i < 4; ++i) {
		handlePattern(i, patternData + patternNum + _currentPos);
		patternData += 4;
	}

	if (_fadeOutCounter != 0 && _fadeOutCounter < 100) {
		_fadeOutCounter += 2;
	}
	_currentPos += 16;
	if (_currentPos >= 1024) {
		_currentPos = 0;
		++_currentOrder;
		if (_currentOrder == _numOrders) {
			_currentOrder = 0;
		}
	}
	debug(7, "_currentOrder=%d/%d _currentPos=%d", _currentOrder, _numOrders, _currentPos);
}

void SfxPlayer::handlePattern(int channel, const byte *patternData) {
	int instrument = patternData[2] >> 4;
	if (instrument != 0) {
		--instrument;
		if (_instrumentsChannelTable[channel] != instrument || _fadeOutCounter != 0) {
			_instrumentsChannelTable[channel] = instrument;
			const int volume = _sfxData[instrument] - _fadeOutCounter;
			_driver->setupChannel(channel, _instrumentsData[instrument], instrument, volume);
		}
	}
	int16 freq = (int16)READ_BE_UINT16(patternData);
	if (freq > 0) {
		_driver->stopChannel(channel);
		_driver->setChannelFrequency(channel, freq);
	}
}

void SfxPlayer::unload() {
	for (int i = 0; i < NUM_INSTRUMENTS; ++i) {
		free(_instrumentsData[i]);
		_instrumentsData[i] = NULL;
	}
	free(_sfxData);
	_sfxData = NULL;
}

} // End of namespace Cine