/*
 * Copyright (C) 2012 Google Inc. All rights reserved.
 *
 * 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. Neither the name of Google Inc. nor the names of its contributors
 *    may be used to endorse or promote products derived from this
 *    software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "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 COPYRIGHT
 * OWNER OR CONTRIBUTORS 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 RTCPeerConnection_h
#define RTCPeerConnection_h

#include "bindings/core/v8/ActiveScriptWrappable.h"
#include "bindings/core/v8/ScriptPromise.h"
#include "core/dom/SuspendableObject.h"
#include "modules/EventTargetModules.h"
#include "modules/crypto/NormalizeAlgorithm.h"
#include "modules/mediastream/MediaStream.h"
#include "modules/peerconnection/RTCIceCandidate.h"
#include "platform/AsyncMethodRunner.h"
#include "public/platform/WebMediaConstraints.h"
#include "public/platform/WebRTCPeerConnectionHandler.h"
#include "public/platform/WebRTCPeerConnectionHandlerClient.h"
#include <memory>

namespace blink {
class ExceptionState;
class MediaStreamTrack;
class RTCAnswerOptions;
class RTCConfiguration;
class RTCDTMFSender;
class RTCDataChannel;
class RTCIceCandidateInitOrRTCIceCandidate;
class RTCOfferOptions;
class RTCPeerConnectionErrorCallback;
class RTCSessionDescription;
class RTCSessionDescriptionCallback;
class RTCSessionDescriptionInit;
class RTCStatsCallback;
class ScriptState;
class VoidCallback;
struct WebRTCConfiguration;

class RTCPeerConnection final : public EventTargetWithInlineData,
                                public WebRTCPeerConnectionHandlerClient,
                                public ActiveScriptWrappable,
                                public SuspendableObject {
  DEFINE_WRAPPERTYPEINFO();
  USING_GARBAGE_COLLECTED_MIXIN(RTCPeerConnection);
  USING_PRE_FINALIZER(RTCPeerConnection, dispose);

 public:
  static RTCPeerConnection* create(ExecutionContext*,
                                   const RTCConfiguration&,
                                   const Dictionary&,
                                   ExceptionState&);
  ~RTCPeerConnection() override;

  ScriptPromise createOffer(ScriptState*, const RTCOfferOptions&);
  ScriptPromise createOffer(ScriptState*,
                            RTCSessionDescriptionCallback*,
                            RTCPeerConnectionErrorCallback*,
                            const Dictionary&,
                            ExceptionState&);

  ScriptPromise createAnswer(ScriptState*, const RTCAnswerOptions&);
  ScriptPromise createAnswer(ScriptState*,
                             RTCSessionDescriptionCallback*,
                             RTCPeerConnectionErrorCallback*,
                             const Dictionary&);

  ScriptPromise setLocalDescription(ScriptState*,
                                    const RTCSessionDescriptionInit&);
  ScriptPromise setLocalDescription(ScriptState*,
                                    const RTCSessionDescriptionInit&,
                                    VoidCallback*,
                                    RTCPeerConnectionErrorCallback*);
  RTCSessionDescription* localDescription();

  ScriptPromise setRemoteDescription(ScriptState*,
                                     const RTCSessionDescriptionInit&);
  ScriptPromise setRemoteDescription(ScriptState*,
                                     const RTCSessionDescriptionInit&,
                                     VoidCallback*,
                                     RTCPeerConnectionErrorCallback*);
  RTCSessionDescription* remoteDescription();

  String signalingState() const;

  void updateIce(ExecutionContext*,
                 const RTCConfiguration&,
                 const Dictionary&,
                 ExceptionState&);

  // Certificate management
  // http://w3c.github.io/webrtc-pc/#sec.cert-mgmt
  static ScriptPromise generateCertificate(
      ScriptState*,
      const AlgorithmIdentifier& keygenAlgorithm,
      ExceptionState&);

  ScriptPromise addIceCandidate(ScriptState*,
                                const RTCIceCandidateInitOrRTCIceCandidate&);
  ScriptPromise addIceCandidate(ScriptState*,
                                const RTCIceCandidateInitOrRTCIceCandidate&,
                                VoidCallback*,
                                RTCPeerConnectionErrorCallback*);

  String iceGatheringState() const;

  String iceConnectionState() const;

  MediaStreamVector getLocalStreams() const;

  MediaStreamVector getRemoteStreams() const;

  MediaStream* getStreamById(const String& streamId);

  void addStream(ExecutionContext*,
                 MediaStream*,
                 const Dictionary& mediaConstraints,
                 ExceptionState&);

  void removeStream(MediaStream*, ExceptionState&);

  ScriptPromise getStats(ScriptState*,
                         RTCStatsCallback* successCallback,
                         MediaStreamTrack* selector = nullptr);
  ScriptPromise getStats(ScriptState*, MediaStreamTrack* selector = nullptr);

  RTCDataChannel* createDataChannel(ExecutionContext*,
                                    String label,
                                    const Dictionary& dataChannelDict,
                                    ExceptionState&);

  RTCDTMFSender* createDTMFSender(MediaStreamTrack*, ExceptionState&);

  void close(ExceptionState&);

  // We allow getStats after close, but not other calls or callbacks.
  bool shouldFireDefaultCallbacks() { return !m_closed && !m_stopped; }
  bool shouldFireGetStatsCallback() { return !m_stopped; }

  DEFINE_ATTRIBUTE_EVENT_LISTENER(negotiationneeded);
  DEFINE_ATTRIBUTE_EVENT_LISTENER(icecandidate);
  DEFINE_ATTRIBUTE_EVENT_LISTENER(signalingstatechange);
  DEFINE_ATTRIBUTE_EVENT_LISTENER(addstream);
  DEFINE_ATTRIBUTE_EVENT_LISTENER(removestream);
  DEFINE_ATTRIBUTE_EVENT_LISTENER(iceconnectionstatechange);
  DEFINE_ATTRIBUTE_EVENT_LISTENER(datachannel);

  // WebRTCPeerConnectionHandlerClient
  void negotiationNeeded() override;
  void didGenerateICECandidate(const WebRTCICECandidate&) override;
  void didChangeSignalingState(SignalingState) override;
  void didChangeICEGatheringState(ICEGatheringState) override;
  void didChangeICEConnectionState(ICEConnectionState) override;
  void didAddRemoteStream(const WebMediaStream&) override;
  void didRemoveRemoteStream(const WebMediaStream&) override;
  void didAddRemoteDataChannel(WebRTCDataChannelHandler*) override;
  void releasePeerConnectionHandler() override;
  void closePeerConnection() override;

  // EventTarget
  const AtomicString& interfaceName() const override;
  ExecutionContext* getExecutionContext() const override;

  // SuspendableObject
  void suspend() override;
  void resume() override;
  void contextDestroyed() override;

  // ScriptWrappable
  // We keep the this object alive until either stopped or closed.
  bool hasPendingActivity() const final { return !m_closed && !m_stopped; }

  DECLARE_VIRTUAL_TRACE();

 private:
  typedef Function<bool()> BoolFunction;
  class EventWrapper : public GarbageCollectedFinalized<EventWrapper> {
   public:
    EventWrapper(Event*, std::unique_ptr<BoolFunction>);
    // Returns true if |m_setupFunction| returns true or it is null.
    // |m_event| will only be fired if setup() returns true;
    bool setup();

    DECLARE_TRACE();

    Member<Event> m_event;

   private:
    std::unique_ptr<BoolFunction> m_setupFunction;
  };

  RTCPeerConnection(ExecutionContext*,
                    const WebRTCConfiguration&,
                    WebMediaConstraints,
                    ExceptionState&);
  void dispose();

  void scheduleDispatchEvent(Event*);
  void scheduleDispatchEvent(Event*, std::unique_ptr<BoolFunction>);
  void dispatchScheduledEvent();
  bool hasLocalStreamWithTrackId(const String& trackId);

  void changeSignalingState(WebRTCPeerConnectionHandlerClient::SignalingState);
  void changeIceGatheringState(
      WebRTCPeerConnectionHandlerClient::ICEGatheringState);
  // Changes the state immediately; does not fire an event.
  // Returns true if the state was changed.
  bool setIceConnectionState(
      WebRTCPeerConnectionHandlerClient::ICEConnectionState);
  // Changes the state asynchronously and fires an event immediately after
  // changing the state.
  void changeIceConnectionState(
      WebRTCPeerConnectionHandlerClient::ICEConnectionState);

  void closeInternal();

  void recordRapporMetrics();

  SignalingState m_signalingState;
  ICEGatheringState m_iceGatheringState;
  ICEConnectionState m_iceConnectionState;

  MediaStreamVector m_localStreams;
  MediaStreamVector m_remoteStreams;

  std::unique_ptr<WebRTCPeerConnectionHandler> m_peerHandler;

  Member<AsyncMethodRunner<RTCPeerConnection>> m_dispatchScheduledEventRunner;
  HeapVector<Member<EventWrapper>> m_scheduledEvents;

  bool m_stopped;
  bool m_closed;

  bool m_hasDataChannels;  // For RAPPOR metrics
};

}  // namespace blink

#endif  // RTCPeerConnection_h