/*******************************************************************************

 Copyright (c) 2009, Charles McGarvey
 All rights reserved.
 
 Redistribution   and   use  in  source  and  binary  forms,  with  or  without
 modification, are permitted provided that the following conditions are met:
 
   * Redistributions  of  source  code  must retain the above copyright notice,
     this list of conditions and the following disclaimer.
   * Redistributions  in binary form must reproduce the above copyright notice,
     this  list of conditions and the following disclaimer in the documentation
     and/or other materials provided with the distribution.
 
 THIS  SOFTWARE  IS  PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 AND  ANY  EXPRESS  OR  IMPLIED  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 DISCLAIMED.  IN  NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
 FOR  ANY  DIRECT,  INDIRECT,  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 DAMAGES  (INCLUDING,  BUT  NOT  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 SERVICES;  LOSS  OF  USE,  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 CAUSED  AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 OR  TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

*******************************************************************************/

#include <cstdio>
#include <deque>
#include <list>
#include <string>

#include <AL/al.h>
#include <vorbis/codec.h>
#include <vorbis/vorbisfile.h>

#include "Engine.hh"
#include "Exception.hh"
#include "Library.hh"
#include "Log.hh"
#include "Sound.hh"
#include "Timer.hh"

#define BUFFER_SIZE (64 * 1024)
//#define BUFFER_SIZE (5*2048)

namespace Mf {


class Sound::Impl
{
public:

	static ALenum getAudioFormat(const vorbis_info* audioInfo)
	{
		if (audioInfo->channels == 1) return AL_FORMAT_MONO16;
		else						  return AL_FORMAT_STEREO16;
	}
	

	class Buffer;
	typedef boost::shared_ptr<Buffer> BufferP;
	
	class Buffer : public Library<Buffer>
	{
	public:

		Buffer(const std::string& name) :
			Library<Buffer>(name),
			mBuffer(-1)
		{
			mOggStream.datasource = 0;
			openFile();
		}

		~Buffer()
		{
			if (mOggStream.datasource)
			{
				ov_clear(&mOggStream);
			}
			if (int(mBuffer) != -1) alDeleteBuffers(1, &mBuffer);
		}


		void openFile()
		{
			if (mOggStream.datasource)
			{
				ov_clear(&mOggStream);
				mOggStream.datasource = 0;
			}

			std::string filePath = Sound::getPath(getName());
			int result = ov_fopen((char*)filePath.c_str(), &mOggStream);

			if (result < 0)
			{
				logWarning("error while loading sound %s",
						getName().c_str());
				throw Exception(ErrorCode::UNKNOWN_AUDIO_FORMAT, getName());
			}

			vorbis_info* vorbisInfo = ov_info(&mOggStream, -1);
			mFormat = getAudioFormat(vorbisInfo);
			mFreq = vorbisInfo->rate;
		}


		void loadAll(ALuint source)
		{
			if (!mOggStream.datasource) openFile();
			if (!mOggStream.datasource) return;

			char data[BUFFER_SIZE];
			int size = 0;

			for (;;)
			{
				int section;
				int result = ov_read(&mOggStream, data + size,
						BUFFER_SIZE - size, 0, 2, 1, &section);

				if (result > 0)
				{
					size += result;
				}
				else
				{
					if (result < 0) logWarning("vorbis playback error");
					break;
				}
			}
			if (size == 0)
			{
				logWarning("decoded no bytes from %s", getName().c_str());
				return;
			}

			alGenBuffers(1, &mBuffer);

			alBufferData(mBuffer, mFormat, data, size, mFreq);
			alSourcei(source, AL_BUFFER, mBuffer);

			// don't need to keep this loaded
			ov_clear(&mOggStream);
			mOggStream.datasource = 0;
		}

		bool stream(ALuint buffer)
		{
			char data[BUFFER_SIZE];
			int size = 0;

			while (size < BUFFER_SIZE)
			{
				int section;
				int result = ov_read(&mOggStream, data + size,
						BUFFER_SIZE - size, 0, 2, 1, &section);

				if (result > 0)
				{
					size += result;
				}
				else
				{
					if (result < 0) logWarning("vorbis playback error");
					break;
				}
			}

			if (size == 0) return false;

			alBufferData(buffer, mFormat, data, size, mFreq);

			return true;
		}

		void rewind()
		{
			if (!mOggStream.datasource) openFile();
			else ov_raw_seek(&mOggStream, 0);
		}


	private:

		OggVorbis_File	mOggStream;
		ALenum			mFormat;
		ALsizei			mFreq;
		ALuint			mBuffer;
	};


	Impl()
	{
		init();
	}

	Impl(const std::string& name)
	{
		init();
		enqueue(name);
	}

	void init()
	{
		// make sure the engine is initialized
		Engine::getInstance();

		mIsLoaded = false;
		mIsPlaying = false;
		mIsLooping = false;

		alGenSources(1, &mSource);

		ALfloat zero[] = {0.0f, 0.0f, 0.0f};
		alSourcef(mSource,  AL_PITCH, 1.0f);
		alSourcef(mSource,  AL_GAIN, 1.0f);
		alSourcefv(mSource, AL_POSITION, zero);
		alSourcefv(mSource, AL_VELOCITY, zero);

		alSourcei(mSource, AL_LOOPING, mIsLooping);
	}

	~Impl()
	{
		stop();

		alDeleteSources(1, &mSource);

		while (!mBuffers.empty())
		{
			alDeleteBuffers(1, &mBuffers.back());
			mBuffers.pop_back();
		}
	}


	void play()
	{
		if (mQueue.empty()) return;

		if (!mIsLoaded) mQueue.front()->loadAll(mSource);

		alSourcePlay(mSource);
		mIsLoaded = true;
	}


	void playStream()
	{
		if (mQueue.empty()) return;

		if (!mIsPlaying)
		{
			alSourcei(mSource, AL_LOOPING, false);
			bufferStream();
		}

		if (!mStreamTimer.isValid())
		{
			mStreamTimer.init(boost::bind(&Impl::streamUpdate, this, _1, _2),
					1.0, Timer::REPEAT);
		}

		alSourcePlay(mSource);
		mIsPlaying = true;
	}

	void bufferStream()
	{
		ALuint buffer;
		for (int i = mBuffers.size(); i <= 8; ++i)
		{
			alGenBuffers(1, &buffer);

			if (mQueue.front()->stream(buffer))
			{
				alSourceQueueBuffers(mSource, 1, &buffer);
				mBuffers.push_back(buffer);
			}
			else
			{
				alDeleteBuffers(1, &buffer);
				break;
			}
		}
	}


	void update()
	{
		ALint finished = 0;

		alGetSourcei(mSource, AL_BUFFERS_PROCESSED, &finished);

		while (finished-- > 0)
		{
			ALuint bufferObj;
			alSourceUnqueueBuffers(mSource, 1, &bufferObj);

			BufferP buffer = mQueue.front();
			bool streamed = buffer->stream(bufferObj);

			if (streamed)
			{
				alSourceQueueBuffers(mSource, 1, &bufferObj);
			}
			else
			{
				// the buffer couldn't be streamed, so get rid of it
				mQueue.pop_front();

				if (!mQueue.empty())
				{
					// begin the next buffer in the queue
					mQueue.front()->rewind();
					mQueue.front()->stream(bufferObj);
					alSourceQueueBuffers(mSource, 1, &bufferObj);
					logInfo("loading new buffer");

					// queue up any unused buffers
					bufferStream();
				}
				else if (mIsLooping)
				{
					// reload the same buffer
					mQueue.push_back(buffer);
					buffer->rewind();
					buffer->stream(bufferObj);
					alSourceQueueBuffers(mSource, 1, &bufferObj);
					logInfo("looping same buffer");
				}
				else
				{
					// nothing more to play, stopping...
					mIsPlaying = false;
					std::remove(mBuffers.begin(), mBuffers.end(), bufferObj);
				}
			}
		}

		ALenum state;
		alGetSourcei(mSource, AL_SOURCE_STATE, &state);

		// restart playing if we're stopped but supposed to be playing... this
		// means we didn't queue enough and the audio skipped :-(
		if (mIsPlaying && state != AL_PLAYING)
		{
			alSourcePlay(mSource);
		}
	}


	void stop()
	{
		alSourceStop(mSource);
		mIsPlaying = false;

		mStreamTimer.invalidate();
	}

	void pause()
	{
		alSourcePause(mSource);
		mIsPlaying = false;

		mStreamTimer.invalidate();
	}


	void setSample(const std::string& name)
	{
		stop();
		alSourcei(mSource, AL_BUFFER, AL_NONE);

		mQueue.clear();
		mIsLoaded = false;

		enqueue(name);

		while (!mBuffers.empty())
		{
			alDeleteBuffers(1, &mBuffers.back());
			mBuffers.pop_back();
		}
	}

	void enqueue(const std::string& name)
	{
		BufferP buffer = Buffer::getInstance(name);
		mQueue.push_back(buffer);
	}


	bool isPlaying() const
	{
		if (mIsPlaying) return true;

		ALenum state;
		alGetSourcei(mSource, AL_SOURCE_STATE, &state);

		return state == AL_PLAYING;
	}


	void setLooping(bool looping)
	{
		mIsLooping = looping;

		ALenum type;
		alGetSourcei(mSource, AL_SOURCE_TYPE, &type);

		if (type != AL_STREAMING)
		{
			alSourcei(mSource, AL_LOOPING, mIsLooping);
		}
	}


	void streamUpdate(Timer& timer, Scalar t)
	{
		// don't let the music die!
		update();
		// TODO - might be nice to also allow using threads for streaming rather
		// than a timer, probably as a compile-time option
	}


	ALuint					mSource;
	std::list<ALuint>		mBuffers;

	bool					mIsLoaded;
	bool					mIsPlaying;
	bool					mIsLooping;

	std::deque<BufferP>		mQueue;

	Timer					mStreamTimer;
};


Sound::Sound() :
	// pass through
	mImpl(new Sound::Impl) {}

Sound::Sound(const std::string& name) :
	// pass through
	mImpl(new Sound::Impl(name)) {}


void Sound::setSample(const std::string& name)
{
	// pass through
	mImpl->setSample(name);
}


void Sound::play()
{
	// pass through
	mImpl->play();
}

void Sound::stop()
{
	// pass through
	mImpl->stop();
}

void Sound::pause()
{
	// pass through
	mImpl->pause();
}


void Sound::toggle()
{
	if (isPlaying()) pause();
	else play();
}

bool Sound::isPlaying() const
{
	// pass through
	return mImpl->isPlaying();
}


void Sound::setPosition(const Vector3& position)
{
	float vec[3] = {position[0], position[1], position[2]};
	alSourcefv(mImpl->mSource, AL_POSITION, vec);
}

void Sound::setVelocity(const Vector3& velocity)
{
	float vec[3] = {velocity[0], velocity[1], velocity[2]};
	alSourcefv(mImpl->mSource, AL_VELOCITY, vec);
}

void Sound::setGain(Scalar gain)
{
	alSourcef(mImpl->mSource, AL_GAIN, float(gain));
}

void Sound::setPitch(Scalar pitch)
{
	alSourcef(mImpl->mSource, AL_PITCH, float(pitch));
}

void Sound::setLooping(bool looping)
{
	// pass through
	mImpl->setLooping(looping);
}


void Sound::setListenerPosition(const Vector3& position)
{
	//alListener3f(AL_POSITION, float(position[0]), float(position[1]),
			//float(position[2]));
	float vec[] = {position[0], position[1], position[2]};
	alListenerfv(AL_POSITION, vec);
}

void Sound::setListenerVelocity(const Vector3& velocity)
{
	//alListener3f(AL_VELOCITY, float(velocity[0]), float(velocity[1]),
			//float(velocity[2]));
	float vec[] = {velocity[0], velocity[1], velocity[2]};
	alListenerfv(AL_VELOCITY, vec);
}

void Sound::setListenerOrientation(const Vector3& forward, const Vector3& up)
{
	float vec[6];
	vec[0] = float(forward[0]);
	vec[1] = float(forward[1]);
	vec[2] = float(forward[2]);
	vec[3] = float(up[0]);
	vec[4] = float(up[1]);
	vec[5] = float(up[2]);
	alListenerfv(AL_ORIENTATION, vec);
}


std::string Sound::getPath(const std::string& name)
{
	std::string path = Resource::getPath("sounds/" + name + ".ogg");
	return path;
}


//~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


void SoundStream::enqueue(const std::string& name)
{
	// pass through
	mImpl->enqueue(name);
}


void SoundStream::play()
{
	// pass through
	mImpl->playStream();
}


} // namespace Mf

/** vim: set ts=4 sw=4 tw=80: *************************************************/