PCSoundManager::PCSoundManager()
{
	fileFactory = new IrrklangFileFactory();

	irrklang::E_SOUND_OUTPUT_DRIVER driver = irrklang::ESOD_WIN_MM;
	ifdef _MAC
		driver = irrklang::ESOD_CORE_AUDIO;
	endif
	
	// Create single-threaded audio engine
	irrKlangEngine = irrklang::createIrrKlangDevice(driver, irrklang::ESEO_LOAD_PLUGINS | irrklang::ESEO_USE_3D_BUFFERS | irrklang::ESEO_PRINT_DEBUG_INFO_TO_DEBUGGER | irrklang::ESEO_PRINT_DEBUG_INFO_TO_STDOUT);
	if (irrKlangEngine == NULL)
	{
		irrKlangEngine = createAnySoundDevice();
	}

	if (irrKlangEngine != NULL)
	{
		irrKlangEngine->addFileFactory(fileFactory);
		irrklangUpdateThread = new Thread("irrUpdThr", &irrklangThreadUpdateFunction, this);
	}
}

	
irrklang::ISoundEngine* PCSoundManager::createAnySoundDevice()
{
	irrklang::ISoundEngine* device = NULL;

	for (unsigned int driver = irrklang::ESOD_AUTO_DETECT; driver < irrklang::ESOD_COUNT && device == NULL; driver++)
	{
		device = createAnySoundDeviceWithDriver(static_cast<irrklang::E_SOUND_OUTPUT_DRIVER>(driver));
	}

	return device;
}


irrklang::ISoundEngine* PCSoundManager::createAnySoundDeviceWithDriver(irrklang::E_SOUND_OUTPUT_DRIVER driver)
{
	irrklang::ISoundDeviceList* deviceList = irrklang::createSoundDeviceList();
	irrklang::ISoundEngine* device = NULL;

	for (int deviceNumber = 0; deviceNumber < deviceList->getDeviceCount() && device == NULL; deviceNumber++)
	{
		const char* deviceID = deviceList->getDeviceID(deviceNumber);

		device = irrklang::createIrrKlangDevice(driver, irrklang::ESEO_DEFAULT_OPTIONS, deviceID);
	}

	return device;
}


void PCSoundManager::irrklangThreadUpdateFunction(void* args)
{
	PCSoundManager* sm = reinterpret_cast<PCSoundManager*>(args);
	FrameTimer* timer = FrameTimer::create();
	float timeElapsed = 0;

	//Irrklang documentation says Irrklang prefers to be updated several times per frame
	const float minTimeToWait = 1.0f / 180.0f;
	
	while (updateThreadShouldKeepRunning)
	{
		if (timeElapsed >= minTimeToWait)
		{
			timeElapsed = 0;
			sm->irrKlangEngine->update();
		}

		timeElapsed += timer->getTimeSincePreviousCall();

		//Check whether we need to wait before another update can be done
		if (timeElapsed < minTimeToWait)
		{
			//Sleep until minTimeToWait has passed
			Thread::sleepInMicroseconds((unsigned int)((minTimeToWait - timeElapsed) * 1000000));
		}
		else
		{
			//We'd like to do another update right away, since updating apparently took a bit of time and we
			//want to update often, but let's first yield to allow others to take the CPU is they need to.
			Thread::yieldCallingThread();
		}
	}

	delete timer;
}