text: /*
    ==============================================================================
  
     This file is part of the JUCE library.
     Copyright (c) 2013 - Raw Material Software Ltd.
  
     Permission is granted to use this software under the terms of either:
     a) the GPL v2 (or any later version)
     b) the Affero GPL v3
  
     Details of these licenses can be found at: www.gnu.org/licenses
  
     JUCE 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.
  
     ------------------------------------------------------------------------------
  
     To release a closed-source product which uses JUCE, commercial licenses are
     available: visit www.juce.com for more information.
  
    ==============================================================================
  */
  
  #ifndef JUCE_BUFFERINGAUDIOSOURCE_H_INCLUDED
  #define JUCE_BUFFERINGAUDIOSOURCE_H_INCLUDED
  
  
  //==============================================================================
  /**
      An AudioSource which takes another source as input, and buffers it using a thread.
  
      Create this as a wrapper around another thread, and it will read-ahead with
      a background thread to smooth out playback. You can either create one of these
      directly, or use it indirectly using an AudioTransportSource.
  
      @see PositionableAudioSource, AudioTransportSource
  */
  class JUCE_API  BufferingAudioSource  : public PositionableAudioSource,
                                          private TimeSliceClient
  {
  public:
      //==============================================================================
      /** Creates a BufferingAudioSource.
  
          @param source                   the input source to read from
          @param backgroundThread         a background thread that will be used for the
                                          background read-ahead. This object must not be deleted
                                          until after any BufferedAudioSources that are using it
                                          have been deleted!
          @param deleteSourceWhenDeleted  if true, then the input source object will
                                          be deleted when this object is deleted
          @param numberOfSamplesToBuffer  the size of buffer to use for reading ahead
          @param numberOfChannels         the number of channels that will be played
      */
      BufferingAudioSource (PositionableAudioSource* source,
                            TimeSliceThread& backgroundThread,
                            bool deleteSourceWhenDeleted,
                            int numberOfSamplesToBuffer,
                            int numberOfChannels = 2);
  
      /** Destructor.
  
          The input source may be deleted depending on whether the deleteSourceWhenDeleted
          flag was set in the constructor.
      */
      ~BufferingAudioSource();
  
      //==============================================================================
      /** Implementation of the AudioSource method. */
      void prepareToPlay (int samplesPerBlockExpected, double sampleRate) override;
  
      /** Implementation of the AudioSource method. */
      void releaseResources() override;
  
      /** Implementation of the AudioSource method. */
      void getNextAudioBlock (const AudioSourceChannelInfo&) override;
  
      //==============================================================================
      /** Implements the PositionableAudioSource method. */
      void setNextReadPosition (int64 newPosition) override;
  
      /** Implements the PositionableAudioSource method. */
      int64 getNextReadPosition() const override;
  
      /** Implements the PositionableAudioSource method. */
      int64 getTotalLength() const override       { return source->getTotalLength(); }
  
      /** Implements the PositionableAudioSource method. */
      bool isLooping() const override             { return source->isLooping(); }
  
  private:
      //==============================================================================
      OptionalScopedPointer<PositionableAudioSource> source;
      TimeSliceThread& backgroundThread;
      int numberOfSamplesToBuffer, numberOfChannels;
      AudioSampleBuffer buffer;
      CriticalSection bufferStartPosLock;
      int64 volatile bufferValidStart, bufferValidEnd, nextPlayPos;
      double volatile sampleRate;
      bool wasSourceLooping, isPrepared;
  
      bool readNextBufferChunk();
      void readBufferSection (int64 start, int length, int bufferOffset);
      int useTimeSlice() override;
  
      JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (BufferingAudioSource)
  };
  
  
  #endif   // JUCE_BUFFERINGAUDIOSOURCE_H_INCLUDED
  