/* 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/>.
 *
 */

/*
 * Copyright (C) 2006-2010 - Frictional Games
 *
 * This file is part of HPL1 Engine.
 */

#include "hpl1/engine/sound/MusicHandler.h"
#include "hpl1/debug.h"
#include "hpl1/engine/math/Math.h"
#include "hpl1/engine/resources/Resources.h"
#include "hpl1/engine/resources/SoundManager.h"
#include "hpl1/engine/sound/LowLevelSound.h"
#include "hpl1/engine/sound/SoundChannel.h"
#include "hpl1/engine/sound/SoundData.h"
#include "hpl1/engine/system/String.h"
#include "hpl1/engine/system/low_level_system.h"

namespace hpl {

//////////////////////////////////////////////////////////////////////////
// CONSTRUCTORS
//////////////////////////////////////////////////////////////////////////

//-----------------------------------------------------------------------

cMusicHandler::cMusicHandler(iLowLevelSound *apLowLevelSound, cResources *apResources) {
	mpLowLevelSound = apLowLevelSound;
	mpResources = apResources;

	mpMainSong = NULL;
	mpLock = NULL;
	mbIsPaused = false;
}

//-----------------------------------------------------------------------

cMusicHandler::~cMusicHandler() {
	if (mpMainSong) {
		hplDelete(mpMainSong->mpStream);
		hplDelete(mpMainSong);
	}

	tMusicEntryListIt it = mlstFadingSongs.begin();
	while (it != mlstFadingSongs.end()) {
		cMusicEntry *pSong = *it;
		hplDelete(pSong->mpStream);
		hplDelete(pSong);

		it = mlstFadingSongs.erase(it);
		// it++;
	}
}

//-----------------------------------------------------------------------

//////////////////////////////////////////////////////////////////////////
// PUBLIC METHODS
//////////////////////////////////////////////////////////////////////////

//-----------------------------------------------------------------------

bool cMusicHandler::Play(const tString &asFileName, float afVolume, float afFadeStepSize, bool abLoop) {
	bool bSongIsPlaying = false;

	if (mpLock != NULL) {
		mpLock->msFileName = asFileName;
		mpLock->mfVolume = afVolume;
		mpLock->mbLoop = abLoop;
		return true;
	}

	if (mpMainSong != NULL)
		if (asFileName == mpMainSong->msFileName)
			bSongIsPlaying = true;

	if (!bSongIsPlaying) {
		// Put the previous song in the fading queue
		if (mpMainSong != NULL) {
			mpMainSong->mfVolumeAdd = afFadeStepSize;
			mlstFadingSongs.push_back(mpMainSong);
		}

		// If there the song to be played is in the fade que, stop it.
		tMusicEntryListIt it = mlstFadingSongs.begin();
		while (it != mlstFadingSongs.end()) {
			cMusicEntry *pSong = *it;
			if (pSong->msFileName == asFileName) {
				pSong->mfVolume = 0;
				pSong->mpStream->Stop();
				hplDelete(pSong->mpStream);
				hplDelete(pSong);

				it = mlstFadingSongs.erase(it);
			} else {
				it++;
			}
		}

		// add it and set its properties
		mpMainSong = hplNew(cMusicEntry, ());

		if (LoadAndStart(asFileName, mpMainSong, 0, abLoop) == false) {
			hplDelete(mpMainSong);
			mpMainSong = NULL;
			return false;
		}
	} else {
		if (mpMainSong->mfMaxVolume == afVolume)
			return true;
	}

	// Set Properties
	mpMainSong->mfMaxVolume = afVolume;
	mpMainSong->mbLoop = abLoop;

	if (mpMainSong->mfMaxVolume > mpMainSong->mfVolume)
		mpMainSong->mfVolumeAdd = afFadeStepSize;
	else
		mpMainSong->mfVolumeAdd = -afFadeStepSize;

	return true;
}

//-----------------------------------------------------------------------

void cMusicHandler::Stop(float afFadeStepSize) {
	if (mpMainSong == NULL)
		return;

	if (afFadeStepSize < 0)
		afFadeStepSize = -afFadeStepSize;

	mpMainSong->mfVolumeAdd = afFadeStepSize;
	if (afFadeStepSize == 0) {
		mpMainSong->mpStream->SetVolume(0);
		mpMainSong->mpStream->Stop();
		mpMainSong->mfVolume = 0;
	}

	mlstFadingSongs.push_back(mpMainSong);
	mpMainSong = NULL;
}

//-----------------------------------------------------------------------

void cMusicHandler::Pause() {
	if (mpMainSong != NULL)
		mpMainSong->mpStream->SetPaused(true);

	tMusicEntryListIt it = mlstFadingSongs.begin();
	while (it != mlstFadingSongs.end()) {
		(*it)->mpStream->SetPaused(true);
		it++;
	}

	mbIsPaused = true;
}

//-----------------------------------------------------------------------

void cMusicHandler::Resume() {
	if (mpMainSong != NULL)
		mpMainSong->mpStream->SetPaused(false);

	tMusicEntryListIt it = mlstFadingSongs.begin();
	while (it != mlstFadingSongs.end()) {
		(*it)->mpStream->SetPaused(false);
		it++;
	}

	mbIsPaused = false;
}

//-----------------------------------------------------------------------

void cMusicHandler::Lock(cMusicLock *apLock) {
	mpLock = apLock;
}

//-----------------------------------------------------------------------

void cMusicHandler::UnLock() {
	mpLock = NULL;
}

//-----------------------------------------------------------------------

tString cMusicHandler::GetCurrentSongName() {
	if (mpMainSong != NULL)
		return mpMainSong->msFileName;
	else
		return "";
}

//-----------------------------------------------------------------------

float cMusicHandler::GetCurrentSongVolume() {
	if (mpMainSong != NULL)
		return mpMainSong->mfVolume;
	else
		return 0;
}

//-----------------------------------------------------------------------

cMusicEntry *cMusicHandler::GetCurrentSong() {
	return mpMainSong;
}

//-----------------------------------------------------------------------

void cMusicHandler::Update(float afTimeStep) {
	if (mbIsPaused)
		return;

	if (mpMainSong != NULL) {
		if (mpMainSong->mpStream->IsPlaying() == false) {
			hplDelete(mpMainSong->mpStream);
			hplDelete(mpMainSong);
			mpMainSong = NULL;
		} else {
			// Update the main song
			mpMainSong->mfVolume += mpMainSong->mfVolumeAdd * afTimeStep;

			if (mpMainSong->mfVolumeAdd > 0) {
				if (mpMainSong->mfVolume >= mpMainSong->mfMaxVolume)
					mpMainSong->mfVolume = mpMainSong->mfMaxVolume;
			} else {
				if (mpMainSong->mfVolume <= mpMainSong->mfMaxVolume)
					mpMainSong->mfVolume = mpMainSong->mfMaxVolume;
			}

			if (mpMainSong->mpStream->GetVolume() != mpMainSong->mfVolume) {
				mpMainSong->mpStream->SetVolume(mpMainSong->mfVolume);
			}
		}
	}

	// Update the fading songs
	tMusicEntryListIt it = mlstFadingSongs.begin();
	while (it != mlstFadingSongs.end()) {
		cMusicEntry *pSong = *it;
		pSong->mfVolume -= pSong->mfVolumeAdd * afTimeStep;

		if (pSong->mfVolume <= 0) {
			pSong->mfVolume = 0;
			pSong->mpStream->Stop();
			hplDelete(pSong->mpStream);
			hplDelete(pSong);

			it = mlstFadingSongs.erase(it);
		} else {
			pSong->mpStream->SetVolume(pSong->mfVolume);
			it++;
		}
	}
}

//-----------------------------------------------------------------------

//////////////////////////////////////////////////////////////////////////
// PRIVATE METHODS
//////////////////////////////////////////////////////////////////////////

//-----------------------------------------------------------------------

bool cMusicHandler::LoadAndStart(const tString &asFileName, cMusicEntry *apSong, float afVolume, bool abLoop) {
	iSoundData *pData = mpResources->GetSoundManager()->CreateSoundData(asFileName, true, abLoop);
	if (pData == NULL) {
		Hpl1::logError(Hpl1::kDebugAudio | Hpl1::kDebugResourceLoading, "Couldn't load music '%s'\n", asFileName.c_str());
		return false;
	}

	iSoundChannel *pStream = pData->CreateChannel(256);
	if (pStream == NULL) {
		Hpl1::logError(Hpl1::kDebugAudio, "Couldn't stream music '%s'!\n", asFileName.c_str());
		return false;
	}

	apSong->msFileName = asFileName;
	apSong->mpStream = pStream;
	apSong->mpStream->SetVolume(afVolume);

	apSong->mpStream->Play();
	apSong->mpStream->SetLooping(abLoop);

	return true;
}
//-----------------------------------------------------------------------

} // namespace hpl