//-----------------------------------------------------------------------------
// Torque Game Engine
// Copyright (C) GarageGames.com, Inc.
//-----------------------------------------------------------------------------

#include "platform/platformAL.h"
#include "audio/audioBuffer.h"
#include "core/stream.h"
#include "console/console.h"
#include "core/frameAllocator.h"

#ifndef TORQUE_NO_OGGVORBIS
#include "vorbis/codec.h"
#endif

#if defined(TORQUE_BIG_ENDIAN)
   #define ENDIAN 1
#else
   #define ENDIAN 0
#endif

//#define LOG_SOUND_LOADS

/// WAV File-header
struct WAVFileHdr
{
  ALubyte  id[4];
  ALsizei  size;
  ALubyte  type[4];
};

//// WAV Fmt-header
struct WAVFmtHdr
{
  ALushort format;
  ALushort channels;
  ALuint   samplesPerSec;
  ALuint   bytesPerSec;
  ALushort blockAlign;
  ALushort bitsPerSample;
};

/// WAV FmtEx-header
struct WAVFmtExHdr
{
  ALushort size;
  ALushort samplesPerBlock;
};

/// WAV Smpl-header
struct WAVSmplHdr
{
  ALuint   manufacturer;
  ALuint   product;
  ALuint   samplePeriod;
  ALuint   note;
  ALuint   fineTune;
  ALuint   SMPTEFormat;
  ALuint   SMPTEOffest;
  ALuint   loops;
  ALuint   samplerData;
  struct
  {
    ALuint identifier;
    ALuint type;
    ALuint start;
    ALuint end;
    ALuint fraction;
    ALuint count;
  }      loop[1];
};

/// WAV Chunk-header
struct WAVChunkHdr
{
  ALubyte  id[4];
  ALuint   size;
};

#define CHUNKSIZE 4096



//--------------------------------------
AudioBuffer::AudioBuffer(StringTableEntry filename)
{
   AssertFatal(StringTable->lookup(filename), "AudioBuffer:: filename is not a string table entry");

   mFilename = filename;
   mLoading = false;
   malBuffer = 0;
}

AudioBuffer::~AudioBuffer()
{
   if( malBuffer != 0 ) {
      alDeleteBuffers( 1, &malBuffer );
   }
}

//--------------------------------------
Resource<AudioBuffer> AudioBuffer::find(const char *filename)
{
   U32 mark = FrameAllocator::getWaterMark();
   char * f2 = NULL;

   Resource<AudioBuffer> buffer = ResourceManager->load(filename);
   if (bool(buffer) == false)
   {
      // wav file doesn't exist, try ogg file instead
      S32 len = dStrlen(filename);
      if (len>3 && !dStricmp(filename+len-4,".wav"))
      {
         f2 = (char*)FrameAllocator::alloc(len+1);
         dStrcpy(f2,filename);
         f2[len-3] = 'o';
         f2[len-2] = 'g';
         f2[len-1] = 'g';
         buffer = ResourceManager->load(filename);
      }
   }

   // if resource still not there, try to create it if file exists
   if (bool(buffer) == false)
   {
      // see if the file exists -- first try default, then try ogg
      if (ResourceManager->getPathOf(filename))
      {
         AudioBuffer *temp = new AudioBuffer(StringTable->insert(filename));
         ResourceManager->add(filename, temp);
         buffer = ResourceManager->load(filename);
      }
      else if (f2 && ResourceManager->getPathOf(f2))
      {
         AudioBuffer *temp = new AudioBuffer(StringTable->insert(f2));
         ResourceManager->add(f2, temp);
         buffer = ResourceManager->load(f2);
      }
   }

   FrameAllocator::setWaterMark(mark);
   return buffer;
}

ResourceInstance* AudioBuffer::construct(Stream &)
{
   return NULL;
}

//-----------------------------------------------------------------
ALuint AudioBuffer::getALBuffer()
{
   if (!alcGetCurrentContext())
      return 0;

   // clear the error state
   alGetError();

   // Intangir> fix for newest openAL from creative (it returns true, yea right 0 is not a valid buffer)
   // it MIGHT not work at all for all i know.
   if (malBuffer && alIsBuffer(malBuffer))
      return malBuffer;

   alGenBuffers(1, &malBuffer);
   if(alGetError() != AL_NO_ERROR)
      return 0;

   ResourceObject * obj = ResourceManager->find(mFilename);
   if(obj)
   {
      bool readSuccess = false;
      S32 len = dStrlen(mFilename);

      if(len > 3 && !dStricmp(mFilename + len - 4, ".wav"))
      {
#ifdef LOG_SOUND_LOADS
         Con::printf("Reading WAV: %s\n", mFilename);
#endif
         readSuccess = readWAV(obj);
      }
#ifndef TORQUE_NO_OGGVORBIS
      else if(len > 3 && !dStricmp(mFilename + len - 4, ".ogg"))
      {
#  ifdef LOG_SOUND_LOADS
         Con::printf("Reading Ogg: %s\n", mFilename);
#  endif
         readSuccess = readOgg(obj);
      }
#endif
      if(readSuccess)
         return(malBuffer);
   }

   alDeleteBuffers(1, &malBuffer);
   return 0;
}

/*!   The Read a WAV file from the given ResourceObject and initialize
      an alBuffer with it.
*/
bool AudioBuffer::readWAV(ResourceObject *obj)
{
   WAVChunkHdr chunkHdr;
   WAVFmtExHdr fmtExHdr;
   WAVFileHdr  fileHdr;
   WAVSmplHdr  smplHdr;
   WAVFmtHdr   fmtHdr;

   ALenum  format = AL_FORMAT_MONO16;
   char   *data   = NULL;
   ALsizei size   = 0;
   ALsizei freq   = 22050;
   ALboolean loop = AL_FALSE;

   Stream *stream = ResourceManager->openStream(obj);
   if (!stream)
      return false;

   stream->read(4, &fileHdr.id[0]);
   stream->read(&fileHdr.size);
   stream->read(4, &fileHdr.type[0]);

   fileHdr.size=((fileHdr.size+1)&~1)-4;

   stream->read(4, &chunkHdr.id[0]);
   stream->read(&chunkHdr.size);
   // unread chunk data rounded up to nearest WORD
   S32 chunkRemaining = chunkHdr.size + (chunkHdr.size&1);

   while ((fileHdr.size!=0) && (stream->getStatus() != Stream::EOS))
   {
      // WAV Format header
      if (!dStrncmp((const char*)chunkHdr.id,"fmt ",4))
      {
         stream->read(&fmtHdr.format);
         stream->read(&fmtHdr.channels);
         stream->read(&fmtHdr.samplesPerSec);
         stream->read(&fmtHdr.bytesPerSec);
         stream->read(&fmtHdr.blockAlign);
         stream->read(&fmtHdr.bitsPerSample);

         if (fmtHdr.format==0x0001)
         {
            format=(fmtHdr.channels==1?
               (fmtHdr.bitsPerSample==8?AL_FORMAT_MONO8:AL_FORMAT_MONO16):
               (fmtHdr.bitsPerSample==8?AL_FORMAT_STEREO8:AL_FORMAT_STEREO16));
            freq=fmtHdr.samplesPerSec;
            chunkRemaining -= sizeof(WAVFmtHdr);
         }
         else
         {
            stream->read(sizeof(WAVFmtExHdr), &fmtExHdr);
            chunkRemaining -= sizeof(WAVFmtExHdr);
         }
      }
      // WAV Format header
      else if (!dStrncmp((const char*)chunkHdr.id,"data",4))
      {
         if (fmtHdr.format==0x0001)
         {
            size=chunkHdr.size;
            data=new char[chunkHdr.size];
            if (data)
            {
               stream->read(chunkHdr.size, data);
#if defined(TORQUE_BIG_ENDIAN)
               // need to endian-flip the 16-bit data.
               if (fmtHdr.bitsPerSample==16) // !!!TBD we don't handle stereo, so may be RL flipped.
               {
                  U16 *ds = (U16*)data;
                  U16 *de = (U16*)(data+size);
                  while (ds<de)
                  {
                     *ds = convertLEndianToHost(*ds);
                     ds++;
                  }
               }
#endif
               chunkRemaining -= chunkHdr.size;
            }
            else
               break;
         }
         else if (fmtHdr.format==0x0011)
         {
            //IMA ADPCM
         }
         else if (fmtHdr.format==0x0055)
         {
            //MP3 WAVE
         }
      }
      // WAV Loop header
      else if (!dStrncmp((const char*)chunkHdr.id,"smpl",4))
      {
         // this struct read is NOT endian safe but it is ok because
         // we are only testing the loops field against ZERO
         stream->read(sizeof(WAVSmplHdr), &smplHdr);
         loop = (smplHdr.loops ? AL_TRUE : AL_FALSE);
         chunkRemaining -= sizeof(WAVSmplHdr);
      }

      // either we have unread chunk data or we found an unknown chunk type
      // loop and read up to 1K bytes at a time until we have
      // read to the end of this chunk
      char buffer[1024];
      AssertFatal(chunkRemaining >= 0, "AudioBuffer::readWAV: remaining chunk data should never be less than zero.");
      while (chunkRemaining > 0)
      {
         S32 readSize = getMin(1024, chunkRemaining);
         stream->read(readSize, buffer);
         chunkRemaining -= readSize;
      }

      fileHdr.size-=(((chunkHdr.size+1)&~1)+8);

      // read next chunk header...
      stream->read(4, &chunkHdr.id[0]);
      stream->read(&chunkHdr.size);
      // unread chunk data rounded up to nearest WORD
      chunkRemaining = chunkHdr.size + (chunkHdr.size&1);
   }

   ResourceManager->closeStream(stream);
   if (data)
   {
      alBufferData(malBuffer, format, data, size, freq);
      delete [] data;
      return (alGetError() == AL_NO_ERROR);
   }

   return false;
}

#ifndef TORQUE_NO_OGGVORBIS
/*!   The Read an Ogg Vorbis file from the given ResourceObject and initialize
      an alBuffer with it.
*/
bool AudioBuffer::readOgg(ResourceObject *obj)
{
   OggVorbisFile vf;
   vorbis_info *vi;

   ALenum  format = AL_FORMAT_MONO16;
   char   *data   = NULL;
   ALsizei size   = 0;
   ALsizei freq   = 22050;
   ALboolean loop = AL_FALSE;
   int current_section = 0;

#if defined(TORQUE_BIG_ENDIAN)
      int endian = 1;
#else
      int endian = 0;
#endif

   int eof = 0;

   Stream *stream = ResourceManager->openStream(obj);
   if (!stream)
      return false;

   if(vf.ov_open(stream, NULL, 0) < 0) {
      return false;
   }

   //Read Vorbis File Info
   vi = vf.ov_info(-1);
   freq = vi->rate;

   long samples = (long)vf.ov_pcm_total(-1);

   if(vi->channels == 1) {
      format = AL_FORMAT_MONO16;
      size = 2 * samples;
   } else {
      format = AL_FORMAT_STEREO16;
      size = 4 * samples;
   }


    data=new char[size];

    if (data)
    {
      long ret = oggRead(&vf, data, size, endian, &current_section);
   }

  /* cleanup */
  vf.ov_clear();

   ResourceManager->closeStream(stream);
   if (data)
   {
      alBufferData(malBuffer, format, data, size, freq);
      delete [] data;
      return (alGetError() == AL_NO_ERROR);
   }

   return false;
}

// ov_read() only returns a maximum of one page worth of data
// this helper function will repeat the read until buffer is full
long AudioBuffer::oggRead(OggVorbisFile* vf, char *buffer,int length,
          int bigendianp,int *bitstream) 
{
   long bytesRead = 0;
   long totalBytes = 0;
   long offset = 0;
   long bytesToRead = 0;
   //while((offset + CHUNKSIZE) < length) {
   while((offset) < length) 
   {
      if((length - offset) < CHUNKSIZE)
         bytesToRead = length - offset;
      else
         bytesToRead = CHUNKSIZE;

      bytesRead = vf->ov_read(buffer, bytesToRead, bigendianp, bitstream);
      if(bytesRead <= 0)
         break;
      offset += bytesRead;
      buffer += bytesRead;
   }
   return offset;
}
#endif