scrypted/docs/plugins/google-home/cast-receiver/cast.js

async function sleep(ms) {
  await new Promise((resolve) => setTimeout(resolve, ms));
}

document.addEventListener("DOMContentLoaded", function (event) {
  const options = new cast.framework.CastReceiverOptions();
  options.disableIdleTimeout = true;

  cast.framework.CastReceiverContext.getInstance().start(options);

  const context = cast.framework.CastReceiverContext.getInstance();
  const playerManager = context.getPlayerManager();

  // intercept the LOAD request to be able to read in a contentId and get data
  playerManager.setMessageInterceptor(cast.framework.messages.MessageType.LOAD, loadRequestData => {
    console.log(loadRequestData);

    const eioUrl = loadRequestData.media.entity || loadRequestData.media.contentId;
    const token = loadRequestData.credentials ?? loadRequestData.media.customData.token;
    const url = new URL(eioUrl)
    const endpointPath = url.pathname;
    const query = {}
    for (const [k, v] of new URLSearchParams(url.search)) {
      query[k] = v;
    }

    const options = {
      path: endpointPath,
      query,
    };

    const socket = eio(`wss://${url.host}`, options);
    socket.on('open', () => {
      socket.send(token);

      const video = document.getElementById('media');

      let pc;

      socket.on('message', async (data) => {
        const json = JSON.parse(data);

        if (pc) {
          for (const candidate of json.candidates) {
            pc.addIceCandidate(candidate);
          }
          return;
        }

        const answerObject = {
          id: json.id,
          candidates: [],
        };

        pc = new RTCPeerConnection(json.configuration);
        const checkConn = () => {
          console.log(pc.connectionState, pc.iceConnectionState);
          if (pc.iceConnectionState === 'failed' || pc.connectionState === 'failed') {
            window.close();
          }
        }

        pc.onconnectionstatechange = checkConn;
        pc.onsignalingstatechange = checkConn;
        pc.ontrack = () => {
          const mediaStream = new MediaStream(
            pc.getReceivers().map((receiver) => receiver.track)
          );
          video.srcObject = mediaStream;
          const remoteAudio = document.createElement("audio");
          remoteAudio.srcObject = mediaStream;
          remoteAudio.play();
        };
        pc.onicecandidate = async (evt) => {
          if (!evt.candidate) {
            return;
          }

          const candidatesObject = {
            id: json.id,
            candidates: [evt.candidate],
          };

          socket.send(JSON.stringify(candidatesObject));
        };
        await pc.setRemoteDescription(json.description);
        const answer = await pc.createAnswer();
        await pc.setLocalDescription(answer);
        answerObject.description = answer;
        socket.send(JSON.stringify(answerObject));
      })

    });

    return null;
  });
});