main.js

window.addEventListener("load", () => {
  let rpcExtensionId = config.rpcExtension.id.chrome;
  if (typeof browser !== "undefined" && typeof chrome !== "undefined") {
    rpcExtensionId = config.rpcExtension.id.firefox;
  }

  // Register Presence
  chrome.runtime.sendMessage(rpcExtensionId, { mode: "active" }, function(response) {
    console.log("Presence registered", response);
  });

  // Wait for presence Requests
  chrome.runtime.onMessage.addListener(function(info, sender, sendResponse) {
    if (info.action == messageType.RPC) {
      console.info("Presence requested", info);
      let buttons = [];

      let isPaused = getIsPaused();

      let endTimestamp = undefined;
      if (!(isPaused ?? true)) {
        let remainingTime = getRemainingTime();
        if (remainingTime !== undefined) endTimestamp = Math.round(Date.now() + remainingTime);
      }

      let stateImageKey = undefined, stateImageText = undefined;
      if (endTimestamp !== undefined) {
        stateImageKey = config.echo360_app.imageKeys.state.playing;
        stateImageText = "playing";
      } else if (isPaused) {
        stateImageKey = config.echo360_app.imageKeys.state.paused;
        stateImageText = "paused";
      }

      let viewURL = getLectureLink();
      if (viewURL !== undefined) buttons.push({
        label: "View Lecture",
        url: viewURL,
      });

      sendResponse({
        clientId: config.echo360_app.id,
        presence: {
          details: getCourseName(),
          state: getLectureName(),

          largeImageKey: "echo360",
          largeImageText: "echo360",

          smallImageKey: stateImageKey,
          smallImageText: stateImageText,

          endTimestamp: endTimestamp,

          buttons: buttons.length > 0 ? buttons : undefined,
        },
      });
    }
  });
});