WhisperLive/Audio-Transcription-Chrome/background.js

/**
 * Removes a tab with the specified tab ID in Google Chrome.
 * @param {number} tabId - The ID of the tab to be removed.
 * @returns {Promise<void>} A promise that resolves when the tab is successfully removed or fails to remove.
 */
function removeChromeTab(tabId) {
  return new Promise((resolve) => {
    chrome.tabs.remove(tabId)
      .then(resolve)
      .catch(resolve);
  });
}


/**
 * Executes a script file in a specific tab in Google Chrome.
 * @param {number} tabId - The ID of the tab where the script should be executed.
 * @param {string} file - The file path or URL of the script to be executed.
 * @returns {Promise<void>} A promise that resolves when the script is successfully executed or fails to execute.
 */
function executeScriptInTab(tabId, file) {
  return new Promise((resolve) => {
    chrome.scripting.executeScript(
      {
        target: { tabId },
        files: [file],
      }, () => {
        resolve();
      }
    );
  });
}


/**
 * Opens the options page of the Chrome extension in a new pinned tab.
 * @returns {Promise<chrome.tabs.Tab>} A promise that resolves with the created tab object.
 */
function openExtensionOptions() {
  return new Promise((resolve) => {
    chrome.tabs.create(
      {
        pinned: true,
        active: false,
        url: `chrome-extension://${chrome.runtime.id}/options.html`,
      },
      (tab) => {
        resolve(tab);
      }
    );
  });
}


/**
 * Retrieves the value associated with the specified key from the local storage in Google Chrome.
 * @param {string} key - The key of the value to retrieve from the local storage.
 * @returns {Promise<any>} A promise that resolves with the retrieved value from the local storage.
 */
function getLocalStorageValue(key) {
  return new Promise((resolve) => {
    chrome.storage.local.get([key], (result) => {
      resolve(result[key]);
    });
  });
}


/**
 * Sends a message to a specific tab in Google Chrome.
 * @param {number} tabId - The ID of the tab to send the message to.
 * @param {any} data - The data to be sent as the message.
 * @returns {Promise<any>} A promise that resolves with the response from the tab.
 */
function sendMessageToTab(tabId, data) {
  return new Promise((resolve) => {
    chrome.tabs.sendMessage(tabId, data, (response) => {
      resolve(response);
    });
  });
}


/**
 * Delays the execution for a specified duration.
 * @param {number} ms - The duration to sleep in milliseconds (default: 0).
 * @returns {Promise<void>} A promise that resolves after the specified duration.
 */
function delayExecution(ms = 0) {
  return new Promise((resolve) => setTimeout(resolve, ms));
}


/**
 * Sets a value associated with the specified key in the local storage of Google Chrome.
 * @param {string} key - The key to set in the local storage.
 * @param {any} value - The value to associate with the key in the local storage.
 * @returns {Promise<any>} A promise that resolves with the value that was set in the local storage.
 */
function setLocalStorageValue(key, value) {
  return new Promise((resolve) => {
    chrome.storage.local.set(
      {
        [key]: value,
      }, () => {
        resolve(value);
      }
    );
  });
}


/**
 * Retrieves the tab object with the specified tabId.
 * @param {number} tabId - The ID of the tab to retrieve.
 * @returns {Promise<object>} - A Promise that resolves to the tab object.
 */
async function getTab(tabId) {
  return new Promise((resolve) => {
    chrome.tabs.get(tabId, (tab) => {
      resolve(tab);
    });
  });
}


/**
 * Starts the capture process for the specified tab.
 * @param {number} tabId - The ID of the tab to start capturing.
 * @returns {Promise<void>} - A Promise that resolves when the capture process is started successfully.
 */
async function startCapture(options) {
  const { tabId } = options;
  const optionTabId = await getLocalStorageValue("optionTabId");
  if (optionTabId) {
    await removeChromeTab(optionTabId);
  }

  try {
    const currentTab = await getTab(tabId);
    if (currentTab.audible) {
      await setLocalStorageValue("currentTabId", currentTab.id);
      await executeScriptInTab(currentTab.id, "content.js");
      await delayExecution(500);

      const optionTab = await openExtensionOptions();

      await setLocalStorageValue("optionTabId", optionTab.id);
      await delayExecution(500);

      await sendMessageToTab(optionTab.id, {
        type: "start_capture",
        data: { 
          currentTabId: currentTab.id, 
          host: options.host, 
          port: options.port, 
          multilingual: options.useMultilingual,
          language: options.language,
          task: options.task,
          modelSize: options.modelSize,
          useVad: options.useVad,
          saveCaptions: options.saveCaptions,
        },
      });
    } else {
      console.log("No Audio");
    }
  } catch (error) {
    console.error("Error occurred while starting capture:", error);
  }
}


/**
 * Stops the capture process and performs cleanup.
 * @returns {Promise<void>} - A Promise that resolves when the capture process is stopped successfully.
 */
async function stopCapture(options) {
  const optionTabId = await getLocalStorageValue("optionTabId");
  const currentTabId = await getLocalStorageValue("currentTabId");

  if (optionTabId) {
    res = await sendMessageToTab(currentTabId, {
      type: "STOP",
      data: { currentTabId: currentTabId, saveCaptions: options.saveCaptions },
    });
    await removeChromeTab(optionTabId);
  }
}


/**
 * Listens for messages from the runtime and performs corresponding actions.
 * @param {Object} message - The message received from the runtime.
 */
chrome.runtime.onMessage.addListener(async (message) => {
  if (message.action === "startCapture") {
    startCapture(message);
  } else if (message.action === "stopCapture") {
    stopCapture(message);
  } else if (message.action === "updateSelectedLanguage") {
    const detectedLanguage = message.detectedLanguage;
    chrome.runtime.sendMessage({ action: "updateSelectedLanguage", detectedLanguage });
    chrome.storage.local.set({ selectedLanguage: detectedLanguage });
  } else if (message.action === "toggleCaptureButtons") {
    chrome.runtime.sendMessage({ action: "toggleCaptureButtons", data: false });
    chrome.storage.local.set({ capturingState: { isCapturing: false } })
    stopCapture({saveCaptions: message.saveCaptions});
  }
});