Delphi WebRTC 库——P2P、ICE、STUN、TURN、DataChannel

uses
  sgcP2P, sgcP2P_DataChannel;

// TFormPeer 持有 FPeer、FChannel 和 FIncoming: TStringList

procedure TFormPeer.CreatePeer;
begin
  FPeer := TsgcRTCPeerConnection.Create(nil);
  FPeer.RTCOptions.ICEServers.AddURL('stun:stun.l.google.com:19302');
  FPeer.RTCOptions.ICEServers.AddURL('turn:turn.example.com:3478',
    'alice', 's3cret');

  FPeer.OnLocalDescription := OnLocalDescription;
  FPeer.OnIceCandidate     := OnIceCandidate;
  FPeer.OnDataChannel      := OnDataChannel;

  // 出站一方。CreateDataChannel 会开启 RTCOptions.DTLS
  FChannel := FPeer.CreateDataChannel('chat');
  FChannel.OnMessage := OnChannelMessage;
  FPeer.CreateOffer;
end;

procedure TFormPeer.OnLocalDescription(Sender: TObject;
  const aType, aSDP: string);
begin
  // aType 为 'offer' 或 'answer'
  SignalToPeer(aType, aSDP);
end;

procedure TFormPeer.OnIceCandidate(Sender: TObject;
  const aCandidate, aSdpMid: string; aSdpMLineIndex: Integer);
begin
  SignalCandidate(aCandidate, aSdpMid, aSdpMLineIndex);
end;

procedure TFormPeer.OnDataChannel(Sender: TObject;
  aChannel: TsgcRTCDataChannel);
begin
  FChannel := aChannel;
  FChannel.OnMessage := OnChannelMessage;
end;

procedure TFormPeer.OnChannelMessage(Sender: TObject;
  const aText: string);
begin
  // 在工作线程上触发，操作控件前请先编组
  FIncoming.Add(aText);
end;

// 点对点发送消息
FChannel.Send('Hello from Delphi');