// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// ChromotingClient is the controller for the Client implementation.

#ifndef REMOTING_CLIENT_CHROMOTING_CLIENT_H_
#define REMOTING_CLIENT_CHROMOTING_CLIENT_H_

#include <memory>
#include <string>

#include "base/callback.h"
#include "base/memory/raw_ptr.h"
#include "base/memory/weak_ptr.h"
#include "base/threading/thread_checker.h"
#include "remoting/client/host_experiment_sender.h"
#include "remoting/protocol/client_authentication_config.h"
#include "remoting/protocol/client_stub.h"
#include "remoting/protocol/clipboard_stub.h"
#include "remoting/protocol/connection_to_host.h"
#include "remoting/protocol/input_stub.h"
#include "remoting/protocol/mouse_input_filter.h"
#include "remoting/protocol/session_config.h"
#include "remoting/protocol/video_stub.h"
#include "remoting/signaling/signal_strategy.h"

namespace base {
class SingleThreadTaskRunner;
}  // namespace base

namespace remoting {

namespace protocol {
class CandidateSessionConfig;
class SessionManager;
class TransportContext;
class VideoRenderer;
}  // namespace protocol

class ClientContext;
class ClientUserInterface;

class ChromotingClient : public SignalStrategy::Listener,
                         public protocol::ConnectionToHost::HostEventCallback,
                         public protocol::ClientStub {
 public:
  // |client_context|, |user_interface| and |video_renderer| must outlive the
  // client. |audio_stream_consumer| may be null, in which case audio will not
  // be requested.
  ChromotingClient(ClientContext* client_context,
                   ClientUserInterface* user_interface,
                   protocol::VideoRenderer* video_renderer,
                   base::WeakPtr<protocol::AudioStub> audio_stream_consumer);

  ChromotingClient(const ChromotingClient&) = delete;
  ChromotingClient& operator=(const ChromotingClient&) = delete;

  ~ChromotingClient() override;

  void set_protocol_config(
      std::unique_ptr<protocol::CandidateSessionConfig> config);

  void set_host_experiment_config(const std::string& experiment_config);

  // Used to set fake/mock objects for tests which use the ChromotingClient.
  void SetConnectionToHostForTests(
      std::unique_ptr<protocol::ConnectionToHost> connection_to_host);

  // Start the client. Must be called on the main thread. |signal_strategy|
  // must outlive the client.
  void Start(SignalStrategy* signal_strategy,
             const protocol::ClientAuthenticationConfig& client_auth_config,
             scoped_refptr<protocol::TransportContext> transport_context,
             const std::string& host_jid,
             const std::string& capabilities);

  // Closes the client and notifies the host of the closure.
  void Close();

  protocol::ConnectionToHost::State connection_state() const {
    return connection_->state();
  }

  protocol::ClipboardStub* clipboard_forwarder() {
    return connection_->clipboard_forwarder();
  }
  protocol::HostStub* host_stub() { return connection_->host_stub(); }
  protocol::InputStub* input_stub() { return &mouse_input_scaler_; }

  // ClientStub implementation.
  void SetCapabilities(const protocol::Capabilities& capabilities) override;
  void SetPairingResponse(
      const protocol::PairingResponse& pairing_response) override;
  void DeliverHostMessage(const protocol::ExtensionMessage& message) override;
  void SetVideoLayout(const protocol::VideoLayout& layout) override;
  void SetTransportInfo(const protocol::TransportInfo& transport_info) override;

  // ClipboardStub implementation for receiving clipboard data from host.
  void InjectClipboardEvent(const protocol::ClipboardEvent& event) override;

  // CursorShapeStub implementation for receiving cursor shape updates.
  void SetCursorShape(const protocol::CursorShapeInfo& cursor_shape) override;

  // KeyboardLayoutStub implementation for sending keyboard layout to client.
  void SetKeyboardLayout(const protocol::KeyboardLayout& layout) override;

  // ConnectionToHost::HostEventCallback implementation.
  void OnConnectionState(protocol::ConnectionToHost::State state,
                         protocol::ErrorCode error) override;
  void OnConnectionReady(bool ready) override;
  void OnRouteChanged(const std::string& channel_name,
                      const protocol::TransportRoute& route) override;

 private:
  // SignalStrategy::StatusObserver interface.
  void OnSignalStrategyStateChange(SignalStrategy::State state) override;
  bool OnSignalStrategyIncomingStanza(const jingle_xmpp::XmlElement* stanza) override;

  // Starts connection once |signal_strategy_| is connected.
  void StartConnection();

  // Called when all channels are connected.
  void OnChannelsConnected();

  base::ThreadChecker thread_checker_;

  scoped_refptr<base::SingleThreadTaskRunner> audio_decode_task_runner_;

  std::unique_ptr<protocol::CandidateSessionConfig> protocol_config_;

  // The following are not owned by this class.
  raw_ptr<ClientUserInterface> user_interface_ = nullptr;
  raw_ptr<protocol::VideoRenderer> video_renderer_ = nullptr;
  base::WeakPtr<protocol::AudioStub> audio_stream_consumer_;
  raw_ptr<SignalStrategy> signal_strategy_ = nullptr;

  std::string host_jid_;
  protocol::ClientAuthenticationConfig client_auth_config_;
  scoped_refptr<protocol::TransportContext> transport_context_;

  std::unique_ptr<protocol::SessionManager> session_manager_;
  std::unique_ptr<protocol::ConnectionToHost> connection_;

  protocol::MouseInputFilter mouse_input_scaler_;

  std::string local_capabilities_;

  // The set of all capabilities supported by the host.
  std::string host_capabilities_;

  // True if |protocol::Capabilities| message has been received.
  bool host_capabilities_received_ = false;

  std::unique_ptr<HostExperimentSender> host_experiment_sender_;
};

}  // namespace remoting

#endif  // REMOTING_CLIENT_CHROMOTING_CLIENT_H_