/*
   orxonox - the future of 3D-vertical-scrollers

   Copyright (C) 2004 orx

   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, or (at your option)
   any later version.

   ### File Specific:
   main-programmer: Benjamin Grauer
   co-programmer: ...

   code has been taken from http://www.devmaster.net/articles.php?catID=6
   The code has been applied to our needs, and many things have been changed.
*/

#define DEBUG_SPECIAL_MODULE DEBUG_MODULE_SOUND

#include "sound_engine.h"

#include "class_list.h"

#include "p_node.h"
#include "util/loading/resource_manager.h"
#include "debug.h"
#include "util/preferences.h"
#include "globals.h"

using namespace std;


//////////////////
/* SOUND-ENGINE */
//////////////////
/**
 * @brief standard constructor
*/
SoundEngine::SoundEngine ()
{
  this->setClassID(CL_SOUND_ENGINE, "SoundEngine");
  this->setName("SoundEngine");

  this->listener = NULL;
  this->bufferList = NULL;
  this->sourceList = NULL;

  this->device = NULL;
  this->context = NULL;

  this->maxSourceCount = 32;

  this->effectsVolume = .80;
  this->musicVolume = .75;

  this->sourceMutex = SDL_CreateMutex();
}

/**
 * @brief the singleton reference to this class
*/
SoundEngine* SoundEngine::singletonRef = NULL;

/**
 * @brief standard destructor
 */
SoundEngine::~SoundEngine ()
{
  // deleting all the SoundSources
  if(this->sourceList != NULL)
  {
    while (this->sourceList->size() > 0)
      delete static_cast<SoundSource*>(this->sourceList->front());
  }

  while(!this->ALSources.empty())
  {
    if (alIsSource(this->ALSources.top()))
    {
      alDeleteSources(1, &this->ALSources.top());
      SoundEngine::checkError("Deleting Source", __LINE__);
    }
    else
      PRINTF(1)("%d is not a Source\n", this->ALSources.top());

    this->ALSources.pop();
  }

  // deleting all the SoundBuffers
  if (this->bufferList != NULL)
  {
    while(this->bufferList->size() > 0)
      ResourceManager::getInstance()->unload(static_cast<SoundBuffer*>(this->bufferList->front()));
  }

  // removing openAL from AudioResource
  //! @todo this should be terminated through alc
  //alutExit();

  SDL_DestroyMutex(this->sourceMutex);

  SoundEngine::singletonRef = NULL;
}

/**
 * @brief loads the settings of the SoundEngine from an ini-file
 */
void SoundEngine::loadSettings()
{
  MultiType channels = Preferences::getInstance()->getString(CONFIG_SECTION_AUDIO, CONFIG_NAME_AUDIO_CHANNELS, "32");
  this->maxSourceCount = channels.getInt();

  MultiType effectsVolume = Preferences::getInstance()->getString(CONFIG_SECTION_AUDIO, CONFIG_NAME_EFFECTS_VOLUME, "80");
  this->effectsVolume = effectsVolume.getFloat()/100.0;

  MultiType musicVolume = Preferences::getInstance()->getString(CONFIG_SECTION_AUDIO, CONFIG_NAME_MUSIC_VOLUME, "75");
  this->musicVolume = musicVolume.getFloat()/100.0;
}

/**
 * @brief creates a new SoundSource.
 * @param fileName The Name to load the SoundBuffer from
 * @param sourceNode The sourceNode to bind this SoundSource to.
 * @returns The newly created SoundSource

   acctualy this is nothing more than a wrapper around the ResourceManager.
*/
SoundSource* SoundEngine::createSource(const std::string& fileName, PNode* sourceNode)
{
  return new SoundSource(sourceNode, (SoundBuffer*)ResourceManager::getInstance()->load(fileName, WAV, RP_LEVEL));
}

/**
 * @brief Sets the doppler values of openAL
 * @param dopplerFactor the extent of the doppler-effect
 * @param dopplerVelocity the Speed the sound travels
*/
void SoundEngine::setDopplerValues(ALfloat dopplerFactor, ALfloat dopplerVelocity)
{
  alDopplerFactor(dopplerFactor);
  this->checkError("Setting Doppler Factor", __LINE__);

  alDopplerVelocity(dopplerVelocity);
  this->checkError("Setting Doppler Velocity", __LINE__);
}


/**
 * @brief retrieves an OpenAL Source from the availiable Sources.
 * @param source the Source to fill with the Value.
 */
void SoundEngine::popALSource(ALuint& source)
{
  assert (source == 0);

  /// @TODO try to create more sources if needed
  if (!this->ALSources.empty())
  {
    SDL_mutexP(this->sourceMutex);
    source = this->ALSources.top();
    this->ALSources.pop();
    SDL_mutexV(this->sourceMutex);
  }
}


/**
 * @brief Pushes an OpenAL Source back into the Stack of known sources
 * @param source the Source to push onto the top of the SourceStack
 */
void SoundEngine::pushALSource(ALuint& source)
{
  if (source != 0)
  {
    SDL_mutexP(this->sourceMutex);
    this->ALSources.push(source);
    SDL_mutexV(this->sourceMutex);
  }
};


/**
 * @brief updates all The positions, Directions and Velocities of all Sounds
 */
void SoundEngine::update()
{
  // updating the Listeners Position
  if (likely(this->listener != NULL))
  {
    alListener3f(AL_POSITION,
                 this->listener->getAbsCoor().x,
                 this->listener->getAbsCoor().y,
                 this->listener->getAbsCoor().z);
    alListener3f(AL_VELOCITY,
                 this->listener->getVelocity().x,
                 this->listener->getVelocity().y,
                 this->listener->getVelocity().z);
    Vector absDirV = this->listener->getAbsDirV();
    ALfloat orientation [6] = {1,0,0, absDirV.x, absDirV.y, absDirV.z};
    alListenerfv(AL_ORIENTATION, orientation);
    SoundEngine::checkError("SoundEngine::update() - Listener Error", __LINE__);
  }
  else
    PRINTF(2)("no listener defined\n");

  // updating all the Sources positions
  if (likely(this->sourceList != NULL || (this->sourceList = ClassList::getList(CL_SOUND_SOURCE)) != NULL))
  {
    list<BaseObject*>::const_iterator sourceIT;
    SoundSource* source;
    for (sourceIT = this->sourceList->begin(); sourceIT != this->sourceList->end(); sourceIT++)
    {
      source = static_cast<SoundSource*>(*sourceIT);
      if (source->isPlaying())
      {
        int play = 0x000;
        alGetSourcei(source->getID(), AL_SOURCE_STATE, &play);
        if (DEBUG > 2)
          SoundEngine::checkError("SoundEngine::update() Play", __LINE__);
        if(play == AL_PLAYING)
        {
          if (likely(source->getNode() != NULL))
          {
            alSource3f(source->getID(), AL_POSITION,
                       source->getNode()->getAbsCoor().x,
                       source->getNode()->getAbsCoor().y,
                       source->getNode()->getAbsCoor().z);
            if (DEBUG > 2)
              SoundEngine::checkError("SoundEngine::update() Set Source Position", __LINE__);
            alSource3f(source->getID(), AL_VELOCITY,
                       source->getNode()->getVelocity().x,
                       source->getNode()->getVelocity().y,
                       source->getNode()->getVelocity().z);
            if (DEBUG > 2)
              SoundEngine::checkError("SoundEngine::update() Set Source Velocity", __LINE__);
          }
        }
        else
        {
          source->stop();
        }
      }
    }
  }
  SoundEngine::checkError("SoundEngine::update()", __LINE__);
}


/**
 *  initializes Audio in general
*/
bool SoundEngine::initAudio()
{
  //   ALenum result;
  //   PRINTF(3)("Initialisazing openAL sound engine\n");
  //   const char* defaultDevice =(const char*) alcGetString(NULL, ALC_DEFAULT_DEVICE_SPECIFIER);
  //   const char* deviceList = (const char*)alcGetString(NULL,ALC_DEVICE_SPECIFIER);
  //   const char* devWalk = deviceList;
  //   //  if (alcIsExtensionPresent(NULL, (const ALCchar*)"ALC_ENUMERATION_EXT") == AL_TRUE)
  //   { // try out enumeration extension
  //     PRINTF(3)("Enumeration-extension found\n");
  //
  //     PRINTF(3)("Default device: %s\n", defaultDevice);
  //     do
  //     {
  //       PRINTF(3)("%s\n", devWalk);
  //       devWalk += strlen(devWalk)+1;
  //     }
  //     while (devWalk[0] != '\0');
  //  }

  // INITIALIZING THE DEVICE:
  //   char deviceName[] =
  //   #ifdef __WIN32__
  //     "Direct3D";
  //   #else
  //     "'( ( devices '( native null ) ) )";
  //   #endif

  this->device = alcOpenDevice(NULL);
  this->checkALCError("opening Device", __LINE__);

  PRINTF(4)("Audio-Specifier: %s\n", (const char*)alcGetString(this->device, ALC_DEVICE_SPECIFIER));
  PRINTF(4)("Audio-Extensions: %s\n", (const char*)alcGetString(this->device, ALC_EXTENSIONS));


  this->context = alcCreateContext(this->device, NULL);
  this->checkALCError("creating Context", __LINE__);

  alcMakeContextCurrent(this->context);
  this->checkALCError("making Context Current", __LINE__);
  // #endif

  this->setDopplerValues(SOUND_DOPPLER_FACTOR, SOUND_DOPPLER_VELOCITY);
  this->allocateSources(this->maxSourceCount);
  this->checkError("Allocating Sources", __LINE__);
}


/**
 * Allocates openAL sources
 * @param count how many sources to allocate
 * @returns true on success, false if at least one source could not be allocated
 */
bool SoundEngine::allocateSources(unsigned int count)
{
  unsigned int failCount = 0;
  for (unsigned int i = 0; i < count; i++)
  {
    ALuint source = 0;

    alGenSources(1, &source);
    this->checkError("allocate Source", __LINE__);
    if (!alIsSource(source))
    {
      PRINTF(5)("not allocated Source\n");
      failCount++;
      continue;
    }

    alSourcef (source, AL_PITCH,    1.0      );
    alSourcef (source, AL_GAIN,     this->getEffectsVolume() );
    alSourcei (source, AL_LOOPING,  AL_FALSE );
    this->ALSources.push(source);
  }
  if (failCount == 0)
    return true;
  else
  {
    PRINTF(2)("Failed to allocate %d of %d SoundSources\n", failCount, count);
  }
}

/**
 * @brief checks for an OpenAL error
 * @param error the ErrorMessage to display
 * @param line on what line did the error occure.
 */
bool SoundEngine::checkError(const std::string& error, unsigned int line)
{
  ALenum errorCode;
  if ((errorCode = alGetError()) != AL_NO_ERROR)
  {
    PRINTF(1)("Error %s (line:%d): '%s'\n", error.c_str(), line, SoundEngine::getALErrorString(errorCode));
    return false;
  }
  else
    return true;
}

/**
 * @brief check for an ALC error.
 * @brief error the Error-String to display
 * @param line on that line, the error occured (debugging mode).
 */
bool SoundEngine::checkALCError(const std::string& error, unsigned int line)
{
  ALenum errorCode;
  if ((errorCode = alcGetError(this->device)) != ALC_NO_ERROR)
  {
    PRINTF(1)("Error %s (line:%d): '%s'\n", error.c_str(), line, SoundEngine::getALCErrorString(errorCode));
    return false;
  }
  else
    return true;
}



void SoundEngine::listDevices()
{
  printf("%s\n",(const char*)alcGetString(NULL, ALC_DEVICE_SPECIFIER));
}

/**
 *  Transforms AL-errors into something readable
 * @param err The error found
*/
const char* SoundEngine::getALErrorString(ALenum err)
{
  switch(err)
  {
    case AL_NO_ERROR:
      return ("AL_NO_ERROR");
    case AL_INVALID_NAME:
      return ("AL_INVALID_NAME");
    case AL_INVALID_ENUM:
      return ("AL_INVALID_ENUM");
    case AL_INVALID_VALUE:
      return ("AL_INVALID_VALUE");
    case AL_INVALID_OPERATION:
      return ("AL_INVALID_OPERATION");
    case AL_OUT_OF_MEMORY:
      return ("AL_OUT_OF_MEMORY");
  };
}


const char* SoundEngine::getALCErrorString(ALenum err)
{
  switch(err)
  {
    case ALC_NO_ERROR:
      return ("AL_NO_ERROR");
    case ALC_INVALID_DEVICE:
      return ("ALC_INVALID_DEVICE");
    case ALC_INVALID_CONTEXT:
      return("ALC_INVALID_CONTEXT");
    case ALC_INVALID_ENUM:
      return("ALC_INVALID_ENUM");
    case ALC_INVALID_VALUE:
      return ("ALC_INVALID_VALUE");
    case ALC_OUT_OF_MEMORY:
      return("ALC_OUT_OF_MEMORY");
  };
}