/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * 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/>.
 *
 */

// Based on Deniz Oezmen's code: http://oezmen.eu/

#include "lastexpress/data/animation.h"

#include "lastexpress/data/sequence.h"
#include "lastexpress/data/snd.h"

#include "lastexpress/debug.h"
#include "lastexpress/helpers.h"

#include "common/events.h"
#include "common/rational.h"
#include "common/stream.h"
#include "common/system.h"

#include "engines/engine.h"

namespace LastExpress {

Animation::Animation() : _stream(nullptr), _currentChunk(nullptr), _overlay(nullptr), _background1(nullptr), _background2(nullptr), _backgroundCurrent(0), _audio(nullptr), _startTime(0), _changed(false) {
}

Animation::~Animation() {
	reset();
}

void Animation::reset() {
	SAFE_DELETE(_overlay);
	SAFE_DELETE(_background1);
	SAFE_DELETE(_background2);
	SAFE_DELETE(_audio);

	_backgroundCurrent = 0;
	_chunks.clear();

	_currentChunk = nullptr;

	SAFE_DELETE(_stream);
}

bool Animation::load(Common::SeekableReadStream *stream, int flag) {
	if (!stream)
		return false;

	reset();

	// Keep stream for later decoding of animation
	_stream = stream;

	// Read header to get the number of chunks
	uint32 numChunks = _stream->readUint32LE();
	debugC(3, kLastExpressDebugGraphics, "Number of chunks in NIS file: %d", numChunks);

	// Check if there is enough data
	if (_stream->size() - _stream->pos() < (signed)(numChunks * sizeof(Chunk))) {
		debugC(2, kLastExpressDebugGraphics, "NIS file seems to be corrupted");
		return false;
	}

	// Read all the chunks
	for (uint32 i = 0; i < numChunks; ++i) {
		Chunk chunk;
		chunk.type = (ChunkType)_stream->readUint16LE();
		chunk.frame = _stream->readUint16LE();
		chunk.size = _stream->readUint32LE();

		_chunks.push_back(chunk);

		debugC(9, kLastExpressDebugGraphics, "Chunk Entry: type 0x%.4x, frame=%d, size=%d", chunk.type, chunk.frame, chunk.size);
	}
	_currentChunk = _chunks.begin();
	_changed = false;
	_startTime = g_system->getMillis();

	return true;
}

bool Animation::process() {
	if (!_currentChunk)
		error("[Animation::process] Current chunk iterator is invalid");

	if (_stream == nullptr || _chunks.size() == 0)
		error("[Animation::process] Trying to show an animation before loading data");

	// TODO: - subtract the time paused by the GUI
	//       - Re-implement to be closer to the original engine
	//       - Add support for subtitles
	//       - Use engine sound queue instead of our own appendable sound instance
	int32 currentFrame = (g_system->getMillis() - _startTime) * 3 / 100;

	// Process all chunks until the current frame
	while (!_changed && _currentChunk != nullptr && currentFrame > _currentChunk->frame && !hasEnded()) {
		switch(_currentChunk->type) {
		//TODO: some info chunks are probably subtitle/sync related
		case kChunkTypeUnknown1:
		case kChunkTypeUnknown2:
		case kChunkTypeUnknown5:
			debugC(9, kLastExpressDebugGraphics | kLastExpressDebugUnknown, "  info chunk: type 0x%.4x (size %d)", _currentChunk->type, _currentChunk->size);
			assert (_currentChunk->frame == 0);
			//TODO: _currentChunk->size?
			break;

		case kChunkTypeAudioInfo:
			debugC(9, kLastExpressDebugGraphics, "  audio info: %d blocks", _currentChunk->size);
			assert (_currentChunk->frame == 0);
			//TODO: save the size?
			_audio = new AppendableSound();
			break;

		case kChunkTypeUnknown4:
			debugC(9, kLastExpressDebugGraphics | kLastExpressDebugUnknown, "  info block 4");
			assert (_currentChunk->frame == 0 && _currentChunk->size == 0);
			//TODO unknown type of chunk
			break;

		case kChunkTypeBackground1:
			debugC(9, kLastExpressDebugGraphics, "  background frame 1 (%d bytes, frame %d)", _currentChunk->size, _currentChunk->frame);
			delete _background1;
			_background1 = processChunkFrame(_stream, *_currentChunk);
			break;

		case kChunkTypeSelectBackground1:
			debugC(9, kLastExpressDebugGraphics, "  select background 1");
			assert (_currentChunk->frame == 0 && _currentChunk->size == 0);
			_backgroundCurrent = 1;
			break;

		case kChunkTypeBackground2:
			debugC(9, kLastExpressDebugGraphics, "  background frame 2 (%d bytes, frame %d)", _currentChunk->size, _currentChunk->frame);
			delete _background2;
			_background2 = processChunkFrame(_stream, *_currentChunk);
			break;

		case kChunkTypeSelectBackground2:
			debugC(9, kLastExpressDebugGraphics, "  select background 2");
			assert (_currentChunk->frame == 0 && _currentChunk->size == 0);
			_backgroundCurrent = 2;
			break;

		case kChunkTypeOverlay:
			debugC(9, kLastExpressDebugGraphics, "  overlay frame (%d bytes, frame %d)", _currentChunk->size, _currentChunk->frame);
			delete _overlay;
			_overlay = processChunkFrame(_stream, *_currentChunk);
			break;

		case kChunkTypeUpdate:
		case kChunkTypeUpdateTransition:
			debugC(9, kLastExpressDebugGraphics, "  update%s: frame %d", _currentChunk->type == 15 ? "" : " with transition", _currentChunk->frame);
			assert (_currentChunk->size == 0);
			_changed = true;
			break;

		case kChunkTypeAudioData:
			debugC(9, kLastExpressDebugGraphics, "  audio (%d blocks, %d bytes, frame %d)", _currentChunk->size / _soundBlockSize, _currentChunk->size, _currentChunk->frame);
			processChunkAudio(_stream, *_currentChunk);

			// Synchronize the audio by resetting the start time
			if (_currentChunk->frame == 0)
				_startTime = g_system->getMillis();
			break;

		case kChunkTypeAudioEnd:
			debugC(9, kLastExpressDebugGraphics, "  audio end: %d blocks", _currentChunk->frame);
			assert (_currentChunk->size == 0);
			_audio->finish();
			//TODO: we need to start the linked sound (.LNK) after the audio from the animation ends
			break;

		default:
			error("[Animation::process] UNKNOWN chunk type=%x frame=%d size=%d", _currentChunk->type, _currentChunk->frame, _currentChunk->size);
			break;
		}
		_currentChunk++;
	}

	return true;
}

bool Animation::hasEnded() {
	return _currentChunk == _chunks.end();
}

Common::Rect Animation::draw(Graphics::Surface *surface) {
	if (!_overlay)
		error("[Animation::draw] Current overlay animation frame is invalid");

	// Paint the background
	if (_backgroundCurrent == 1 && _background1)
		_background1->draw(surface);
	else if (_backgroundCurrent == 2 && _background2)
		_background2->draw(surface);

	// Paint the overlay
	_overlay->draw(surface);

	//TODO
	return Common::Rect();
}

AnimFrame *Animation::processChunkFrame(Common::SeekableReadStream *in, const Chunk &c) const {
	assert (c.frame == 0);

	// Create a temporary chunk buffer
	Common::SeekableReadStream *str = in->readStream(c.size);

	// Read the frame information
	FrameInfo i;
	i.read(str, false);

	// Decode the frame
	AnimFrame *f = new AnimFrame(str, i, true);

	// Delete the temporary chunk buffer
	delete str;

	return f;
}

void Animation::processChunkAudio(Common::SeekableReadStream *in, const Chunk &c) {
	if (!_audio)
		error("[Animation::processChunkAudio] Audio stream is invalid");

	// Skip the Snd header, to queue just the audio blocks
	uint32 size = c.size;
	if ((c.size % 739) != 0) {
		// Read Snd header
		uint32 header1 = in->readUint32LE();
		uint16 header2 = in->readUint16LE();
		debugC(4, kLastExpressDebugSound, "Start ADPCM: %d, %d", header1, header2);
		size -= 6;
	}

	// Append the current chunk to the Snd
	_audio->queueBuffer(in->readStream(size));
}

// TODO: this method will probably go away and be integrated in the main loop
void Animation::play() {
	Common::EventManager *eventMan = g_system->getEventManager();
	while (!hasEnded() && !Engine::shouldQuit()) {
		process();

		if (_changed) {
			// Create a temporary surface to merge the overlay with the background
			Graphics::Surface *s = new Graphics::Surface;
			s->create(640, 480, Graphics::PixelFormat(2, 5, 5, 5, 0, 10, 5, 0, 0));

			draw(s);

			// XXX: Update the screen
			g_system->copyRectToScreen(s->getPixels(), s->pitch, 0, 0, s->w, s->h);

			// Free the temporary surface
			s->free();
			delete s;

			_changed = false;
		}

		g_system->updateScreen();

		//FIXME: implement subtitles
		g_system->delayMillis(20);

		// Handle right-click to interrupt animations
		Common::Event ev = Common::Event();
		while (eventMan->pollEvent(ev)) {
			if (ev.type == Common::EVENT_RBUTTONUP) {
				// Stop audio
				if (_audio)
					_audio->finish();

				// TODO start LNK file sound?
				return;
			}
		}
	}
}

} // End of namespace LastExpress