app.js

const { SettingsManager } = require("./SettingsManager");
const { TokenManager } = require("./TokenManager");

let settingsManager = new SettingsManager();
let tokenManager = new TokenManager();

if (typeof browser == "undefined") {
  var browser = chrome;
}


/**
 * Handle messages between content scripts and background script:
 * 1. Handles events where the user changed search settings so they
 *    can be synchronized with the extension storage.
 * 2. Handle attaching anonymous tokens to the search request of the user
 *    so the request can be properly authorized.
 */
browser.runtime.onMessage.addListener((request, sender, sendResponse) => {
  if (!request.hasOwnProperty("type")) return;
  if (request.type == "settings_set" && request.hasOwnProperty("settings")) {
    settingsManager.set(request.settings).then(() => {
      sendResponse({ status: "ok" });
    }).catch(error => {
      console.trace(error);
      sendResponse({ status: "error" });
    });
    return true;
  }
  if (request.type == "settings_remove" && request.hasOwnProperty("setting_key")) {
    if (request.setting_key == "key") {
      tokenManager.store_key(null).then(() => {
        sendResponse({ status: "ok" });
      }).catch(error => {
        console.trace(error);
        sendResponse({ status: "error" });
      });
    } else {
      settingsManager.remove(request.setting_key).then(() => {
        sendResponse({ status: "ok" });
      }).catch(error => {
        console.trace(error);
        sendResponse({ status: "error" });
      });
    }
    return true;
  }
  if (request.type == "tokenauthorization") {
    tokenManager.prepare_token_auth(request.cost).then(() => {
      sendResponse({ status: "ok" });
    }).catch(error => {
      console.trace(error);
      sendResponse({ status: "error" });
    });
    return true;
  }
});

/**
 * When the user enables/disables storage of settings within this
 * web-extension we'll grab all existing settings and put it into
 * the web-extension or vise versa.
 * Those settings will also be disabled if the user removes the necessary
 * host permissions from the extension or enabled if they get externally granted
 * and the user already enabled storage of the settings
 */
browser.storage.onChanged.addListener(async (changes, areaName) => {
  settingsManager.handleStorageChange(changes);
  tokenManager.handleStorageChange(changes);
});
browser.permissions.onAdded.addListener(async (permissions) => {
  await settingsManager.handlePermissionsChange(permissions);
  await tokenManager.handlePermissionsChange(permissions);
});
browser.permissions.onRemoved.addListener(async (permissions) => {
  await settingsManager.handlePermissionsChange(permissions);
  await tokenManager.handlePermissionsChange(permissions);
});

/**
 * Make sure we also catch changes in search settings when they
 * are added i.e. using the dev tools or the setting cookies
 * are getting restored in other ways.
 */
browser.cookies.onChanged.addListener(async changeInfo => {
  await settingsManager.handleCookieChange(changeInfo);
  await tokenManager.handleCookieChange(changeInfo);
})

/**
 * Alternatively catch changes in search settings by parsing the
 * cookies in response headers to make sure the webextensions
 * stores all search settings consistently.
 * 
 * Headers will not be modified in those listeners.
 */
// Handle Request Headers
let extraInfoSpecRequest = ["requestHeaders"];
if (BROWSER == "CHROME") {
  extraInfoSpecRequest.push("extraHeaders");
}
browser.webRequest.onBeforeSendHeaders.addListener(
  async (details) => {
    let headers = await tokenManager.handleRequestHeaders(details);
    return { requestHeaders: headers };
  },
  {
    urls: ["https://metager.org/*", "https://metager.de/*"],
  },
  extraInfoSpecRequest
);
// Handle Response Headers
let extraInfoSpecResponse = ["responseHeaders"];
if (BROWSER == "CHROME") {
  extraInfoSpecResponse.push("extraHeaders");
}
browser.webRequest.onHeadersReceived.addListener(
  (details) => {

    settingsManager.handleResponseHeaders(details);
    tokenManager.handleResponseHeaders(details);
  },
  {
    urls: ["https://metager.org/*", "https://metager.de/*"],
  },
  extraInfoSpecResponse
);

/**
 * Open settings page when user installs the addon
 * as additional permissions might be required to use
 * all features of this extension.
 * Opening the page on update is not required if the user comes from
 * a version that already has a settings page included
 */
browser.runtime.onInstalled.addListener(details => {
  let open_settings_page = false;

  if (details.reason == "update" && details.previousVersion == "0.0.1.3") {
    open_settings_page = true;
  }

  if (details.reason == "install") {
    open_settings_page = true;
  }

  if (details.temporary == true) {
    open_settings_page = false;
  }

  if (open_settings_page) {
    browser.runtime.openOptionsPage();
  }
})