text: /*
   * Copyright 2017-2018 Amazon.com, Inc. or its affiliates. All Rights Reserved.
   *
   * Licensed under the Apache License, Version 2.0 (the "License").
   * You may not use this file except in compliance with the License.
   * A copy of the License is located at
   *
   *     http://aws.amazon.com/apache2.0/
   *
   * or in the "license" file accompanying this file. This file is distributed
   * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
   * express or implied. See the License for the specific language governing
   * permissions and limitations under the License.
   */
  
  #ifndef ALEXA_CLIENT_SDK_MEDIAPLAYER_GSTREAMERMEDIAPLAYER_INCLUDE_MEDIAPLAYER_SOURCEINTERFACE_H_
  #define ALEXA_CLIENT_SDK_MEDIAPLAYER_GSTREAMERMEDIAPLAYER_INCLUDE_MEDIAPLAYER_SOURCEINTERFACE_H_
  
  #include "MediaPlayer/PipelineInterface.h"
  
  #include <AVSCommon/Utils/RequiresShutdown.h>
  
  namespace alexaClientSDK {
  namespace mediaPlayer {
  
  /**
   * Interface to request operations on an audio source.
   */
  class SourceInterface : public avsCommon::utils::RequiresShutdown {
  public:
      /**
       * Constructor, which also constructs RequiresShutdown.
       *
       * @param className The name of the class to be passed to @c RequiresShutdown.
       */
      SourceInterface(const std::string& className) : RequiresShutdown(className) {
      }
  
      /**
       * Destructor.
       */
      virtual ~SourceInterface() = default;
  
      /**
       * Internally, a source may need additional processing after EOS is reached.
       * This function will process that data.
       *
       * @return A boolean indicating whether the process operation was successful.
       */
      virtual bool handleEndOfStream() = 0;
  
      /**
       * Internally, a source may have additional data after processing an EOS.
       * This function indicates whether there is additional data, and should be called
       * after @c handleEndOfStream().
       *
       * @return A boolean indicating whether the source has additional data to be played.
       */
      virtual bool hasAdditionalData() = 0;
  
      /**
       * Perform preprocessing  of the source. Must be called before reading from the source.
       */
      virtual void preprocess() = 0;
  
      /**
       * Indicates whether a source is local or remote from the perspective of the MediaPlayer (e.g. playing out of the
       * SDS is local, playing a URL is remote).
       *
       * @return A boolean indicating whether the source is from a remote or local source
       */
      virtual bool isPlaybackRemote() const = 0;
  };
  
  }  // namespace mediaPlayer
  }  // namespace alexaClientSDK
  
  #endif  // ALEXA_CLIENT_SDK_MEDIAPLAYER_GSTREAMERMEDIAPLAYER_INCLUDE_MEDIAPLAYER_SOURCEINTERFACE_H_
  