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/*
 * libjingle
 * Copyright 2004--2007, Google Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *  1. Redistributions of source code must retain the above copyright notice,
 *     this list of conditions and the following disclaimer.
 *  2. Redistributions in binary form must reproduce the above copyright notice,
 *     this list of conditions and the following disclaimer in the documentation
 *     and/or other materials provided with the distribution.
 *  3. The name of the author may not be used to endorse or promote products
 *     derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef TALK_SESSION_PHONE_MEDIAENGINE_H_
#define TALK_SESSION_PHONE_MEDIAENGINE_H_

#ifdef OSX
#include <CoreAudio/CoreAudio.h>
#endif

#include <string>
#include <vector>

#include "talk/base/sigslotrepeater.h"
#include "talk/session/phone/codec.h"
#include "talk/session/phone/devicemanager.h"
#include "talk/session/phone/mediachannel.h"
#include "talk/session/phone/videocommon.h"

namespace cricket {

// A class for playing out soundclips.
class SoundclipMedia {
 public:
  enum SoundclipFlags {
    SF_LOOP = 1,
  };

  virtual ~SoundclipMedia() {}

  // Plays a sound out to the speakers with the given audio stream. The stream
  // must be 16-bit little-endian 16 kHz PCM. If a stream is already playing
  // on this SoundclipMedia, it is stopped. If clip is NULL, nothing is played.
  // Returns whether it was successful.
  virtual bool PlaySound(const char *clip, int len, int flags) = 0;
};

// MediaEngine is an abstraction of a media engine which can be subclassed
// to support different media componentry backends. It supports voice and
// video operations in the same class to facilitate proper synchronization
// between both media types.
class MediaEngine {
 public:
  // TODO: Move this to a global location (also used in DeviceManager)
  // Capabilities of the media engine.
  enum Capabilities {
    AUDIO_RECV = 1 << 0,
    AUDIO_SEND = 1 << 1,
    VIDEO_RECV = 1 << 2,
    VIDEO_SEND = 1 << 3,
  };

  // Bitmask flags for options that may be supported by the media engine
  // implementation
  enum AudioOptions {
    ECHO_CANCELLATION = 1 << 0,
    AUTO_GAIN_CONTROL = 1 << 1,
    DEFAULT_AUDIO_OPTIONS = ECHO_CANCELLATION | AUTO_GAIN_CONTROL
  };
  enum VideoOptions {
  };

  virtual ~MediaEngine() {}
  static MediaEngine* Create();

  // Initialization
  // Starts the engine.
  virtual bool Init() = 0;
  // Shuts down the engine.
  virtual void Terminate() = 0;
  // Returns what the engine is capable of, as a set of Capabilities, above.
  virtual int GetCapabilities() = 0;

  // MediaChannel creation
  // Creates a voice media channel. Returns NULL on failure.
  virtual VoiceMediaChannel *CreateChannel() = 0;
  // Creates a video media channel, paired with the specified voice channel.
  // Returns NULL on failure.
  virtual VideoMediaChannel *CreateVideoChannel(
      VoiceMediaChannel* voice_media_channel) = 0;

  // Creates a soundclip object for playing sounds on. Returns NULL on failure.
  virtual SoundclipMedia *CreateSoundclip() = 0;

  // Configuration
  // Sets global audio options. "options" are from AudioOptions, above.
  virtual bool SetAudioOptions(int options) = 0;
  // Sets global video options. "options" are from VideoOptions, above.
  virtual bool SetVideoOptions(int options) = 0;
  // Sets the default (maximum) codec/resolution and encoder option to capture
  // and encode video.
  virtual bool SetDefaultVideoEncoderConfig(const VideoEncoderConfig& config)
      = 0;

  // Device selection
  // TODO: Add method for selecting the soundclip device.
  virtual bool SetSoundDevices(const Device* in_device,
                               const Device* out_device) = 0;
  virtual bool SetVideoCaptureDevice(const Device* cam_device) = 0;

  // Device configuration
  // Sets the current speaker volume, as a value between 0 and 255.
  virtual bool SetOutputVolume(int level) = 0;

  // Local monitoring
  // Gets the current microphone level, as a value between 0 and 10.
  virtual int GetInputLevel() = 0;
  // Starts or stops the local microphone. Useful if local mic info is needed
  // prior to a call being connected; the mic will be started automatically
  // when a VoiceMediaChannel starts sending.
  virtual bool SetLocalMonitor(bool enable) = 0;
  // Installs a callback for raw frames from the local camera.
  virtual bool SetLocalRenderer(VideoRenderer* renderer) = 0;
  // Starts/stops local camera.
  virtual CaptureResult SetVideoCapture(bool capture) = 0;

  virtual const std::vector<AudioCodec>& audio_codecs() = 0;
  virtual const std::vector<VideoCodec>& video_codecs() = 0;
  virtual bool FindAudioCodec(const AudioCodec &codec) = 0;
  virtual bool FindVideoCodec(const VideoCodec &codec) = 0;

  // Logging control
  virtual void SetVoiceLogging(int min_sev, const char* filter) = 0;
  virtual void SetVideoLogging(int min_sev, const char* filter) = 0;

  sigslot::repeater1<CaptureResult> SignalVideoCaptureResult;
};

// CompositeMediaEngine constructs a MediaEngine from separate
// voice and video engine classes.
template<class VOICE, class VIDEO>
class CompositeMediaEngine : public MediaEngine {
 public:
  CompositeMediaEngine() {}
  virtual bool Init() {
    if (!voice_.Init())
      return false;
    if (!video_.Init()) {
      voice_.Terminate();
      return false;
    }
    SignalVideoCaptureResult.repeat(video_.SignalCaptureResult);
    return true;
  }
  virtual void Terminate() {
    video_.Terminate();
    voice_.Terminate();
  }

  virtual int GetCapabilities() {
    return (voice_.GetCapabilities() | video_.GetCapabilities());
  }
  virtual VoiceMediaChannel *CreateChannel() {
    return voice_.CreateChannel();
  }
  virtual VideoMediaChannel *CreateVideoChannel(VoiceMediaChannel* channel) {
    return video_.CreateChannel(channel);
  }
  virtual SoundclipMedia *CreateSoundclip() {
    return voice_.CreateSoundclip();
  }

  virtual bool SetAudioOptions(int o) {
    return voice_.SetOptions(o);
  }
  virtual bool SetVideoOptions(int o) {
    return video_.SetOptions(o);
  }
  virtual bool SetDefaultVideoEncoderConfig(const VideoEncoderConfig& config) {
    return video_.SetDefaultEncoderConfig(config);
  }

  virtual bool SetSoundDevices(const Device* in_device,
                               const Device* out_device) {
    return voice_.SetDevices(in_device, out_device);
  }
  virtual bool SetVideoCaptureDevice(const Device* cam_device) {
    return video_.SetCaptureDevice(cam_device);
  }

  virtual bool SetOutputVolume(int level) {
    return voice_.SetOutputVolume(level);
  }

  virtual int GetInputLevel() {
    return voice_.GetInputLevel();
  }
  virtual bool SetLocalMonitor(bool enable) {
    return voice_.SetLocalMonitor(enable);
  }
  virtual bool SetLocalRenderer(VideoRenderer* renderer) {
    return video_.SetLocalRenderer(renderer);
  }
  virtual CaptureResult SetVideoCapture(bool capture) {
    return video_.SetCapture(capture);
  }

  virtual const std::vector<AudioCodec>& audio_codecs() {
    return voice_.codecs();
  }
  virtual const std::vector<VideoCodec>& video_codecs() {
    return video_.codecs();
  }

  virtual bool FindAudioCodec(const AudioCodec &codec) {
    return voice_.FindCodec(codec);
  }
  virtual bool FindVideoCodec(const VideoCodec &codec) {
    return video_.FindCodec(codec);
  }

  virtual void SetVoiceLogging(int min_sev, const char* filter) {
    return voice_.SetLogging(min_sev, filter);
  }
  virtual void SetVideoLogging(int min_sev, const char* filter) {
    return video_.SetLogging(min_sev, filter);
  }

 private:
  VOICE voice_;
  VIDEO video_;
};

class NullVoiceMediaChannel : public VoiceMediaChannel {
 public:
  explicit NullVoiceMediaChannel() {}
  ~NullVoiceMediaChannel() {}
  // MediaChannel implementations
  virtual void OnPacketReceived(talk_base::Buffer* packet) {}
  virtual void OnRtcpReceived(talk_base::Buffer* packet) {}
  virtual void SetSendSsrc(uint32 id) {}
  virtual bool SetRtcpCName(const std::string& cname) { return true; }
  virtual bool Mute(bool on) { return true; }
  virtual bool SetSendBandwidth(bool autobw, int bps) { return true; }
  virtual bool SetOptions(int options) { return true; }
  // VoiceMediaChannel implementations
  virtual bool SetRecvCodecs(const std::vector<AudioCodec> &codecs) {
    return true;
  }
  virtual bool SetSendCodecs(const std::vector<AudioCodec> &codecs) {
    return true;
  }
  virtual bool SetPlayout(bool playout) { return true; }
  virtual bool SetSend(SendFlags flag) { return true; }
  virtual bool AddStream(uint32 ssrc) { return true; }
  virtual bool RemoveStream(uint32 ssrc) { return true; }
  virtual bool GetActiveStreams(AudioInfo::StreamList* streams) { return true; }
  virtual int GetOutputLevel() { return 0; }
  virtual void SetRingbackTone(const char *buf, int len) {}
  virtual bool PlayRingbackTone(bool play, bool loop) { return true; }
  virtual bool PressDTMF(int event, bool playout) { return true; }
  virtual bool GetStats(VoiceMediaInfo* info) { return false; }
};

// NullVoiceEngine can be used with CompositeMediaEngine in the case where only
// a video engine is desired.
class NullVoiceEngine {
 public:
  bool Init() { return true; }
  void Terminate() {}
  int GetCapabilities() { return 0; }
  VoiceMediaChannel* CreateChannel() {
    // TODO: See if we can make things work without requiring
    // allocation of a channel.
    return new NullVoiceMediaChannel();
  }
  SoundclipMedia* CreateSoundclip() {
    return NULL;
  }
  bool SetOptions(int opts) { return true; }
  bool SetDevices(const Device* in_device, const Device* out_device) {
    return true;
  }
  bool SetOutputVolume(int level) { return true; }
  int GetInputLevel() { return 0; }
  bool SetLocalMonitor(bool enable) { return true; }
  const std::vector<AudioCodec>& codecs() { return codecs_; }
  bool FindCodec(const AudioCodec&) { return false; }
  void SetLogging(int min_sev, const char* filter) {}
 private:
  std::vector<AudioCodec> codecs_;
};

// NullVideoEngine can be used with CompositeMediaEngine in the case where only
// a voice engine is desired.
class NullVideoEngine {
 public:
  bool Init() { return true; }
  void Terminate() {}
  int GetCapabilities() { return 0; }
  VideoMediaChannel* CreateChannel(VoiceMediaChannel* voice_media_channel) {
    return NULL;
  }
  bool SetOptions(int opts) { return true; }
  bool SetDefaultEncoderConfig(const VideoEncoderConfig& config) {
    return true;
  }
  bool SetCaptureDevice(const Device* cam_device) { return true; }
  bool SetLocalRenderer(VideoRenderer* renderer) { return true; }
  CaptureResult SetCapture(bool capture) { return CR_SUCCESS;  }
  const std::vector<VideoCodec>& codecs() { return codecs_; }
  bool FindCodec(const VideoCodec&) { return false; }
  void SetLogging(int min_sev, const char* filter) {}
  sigslot::signal1<CaptureResult> SignalCaptureResult;
 private:
  std::vector<VideoCodec> codecs_;
};

typedef CompositeMediaEngine<NullVoiceEngine, NullVideoEngine> NullMediaEngine;

}  // namespace cricket

#endif  // TALK_SESSION_PHONE_MEDIAENGINE_H_