/**
 * Copyright 2017 Google Inc. All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
const os = require('os');
const path = require('path');
const removeFolder = require('rimraf');
const childProcess = require('child_process');
const BrowserFetcher = require('./BrowserFetcher');
const {Connection} = require('./Connection');
const {Browser} = require('./Browser');
const readline = require('readline');
const fs = require('fs');
const {helper, debugError} = require('./helper');
const {TimeoutError} = require('./Errors');
const WebSocketTransport = require('./WebSocketTransport');
const PipeTransport = require('./PipeTransport');

const mkdtempAsync = helper.promisify(fs.mkdtemp);
const removeFolderAsync = helper.promisify(removeFolder);

const CHROME_PROFILE_PATH = path.join(os.tmpdir(), 'puppeteer_dev_profile-');

const DEFAULT_ARGS = [
  '--disable-background-networking',
  '--disable-background-timer-throttling',
  '--disable-breakpad',
  '--disable-client-side-phishing-detection',
  '--disable-default-apps',
  '--disable-dev-shm-usage',
  '--disable-extensions',
  // TODO: Support OOOPIF. @see https://github.com/GoogleChrome/puppeteer/issues/2548
  '--disable-features=site-per-process',
  '--disable-hang-monitor',
  '--disable-popup-blocking',
  '--disable-prompt-on-repost',
  '--disable-sync',
  '--disable-translate',
  '--metrics-recording-only',
  '--no-first-run',
  '--safebrowsing-disable-auto-update',
  '--enable-automation',
  '--password-store=basic',
  '--use-mock-keychain',
];

class Launcher {
  /**
   * @param {string} projectRoot
   * @param {string} preferredRevision
   * @param {boolean} isPuppeteerCore
   */
  constructor(projectRoot, preferredRevision, isPuppeteerCore) {
    this._projectRoot = projectRoot;
    this._preferredRevision = preferredRevision;
    this._isPuppeteerCore = isPuppeteerCore;
  }

  /**
   * @param {!(LaunchOptions & ChromeArgOptions & BrowserOptions)=} options
   * @return {!Promise<!Browser>}
   */
  async launch(options = {}) {
    const {
      ignoreDefaultArgs = false,
      args = [],
      dumpio = false,
      executablePath = null,
      pipe = false,
      env = process.env,
      handleSIGINT = true,
      handleSIGTERM = true,
      handleSIGHUP = true,
      ignoreHTTPSErrors = false,
      defaultViewport = {width: 800, height: 600},
      slowMo = 0,
      timeout = 30000
    } = options;

    const chromeArguments = [];
    if (!ignoreDefaultArgs)
      chromeArguments.push(...this.defaultArgs(options));
    else if (Array.isArray(ignoreDefaultArgs))
      chromeArguments.push(...this.defaultArgs(options).filter(arg => ignoreDefaultArgs.indexOf(arg) === -1));
    else
      chromeArguments.push(...args);

    let temporaryUserDataDir = null;

    if (!chromeArguments.some(argument => argument.startsWith('--remote-debugging-')))
      chromeArguments.push(pipe ? '--remote-debugging-pipe' : '--remote-debugging-port=0');
    if (!chromeArguments.some(arg => arg.startsWith('--user-data-dir'))) {
      temporaryUserDataDir = await mkdtempAsync(CHROME_PROFILE_PATH);
      chromeArguments.push(`--user-data-dir=${temporaryUserDataDir}`);
    }

    let chromeExecutable = executablePath;
    if (!executablePath) {
      const {missingText, executablePath} = this._resolveExecutablePath();
      if (missingText)
        throw new Error(missingText);
      chromeExecutable = executablePath;
    }

    const usePipe = chromeArguments.includes('--remote-debugging-pipe');
    const stdio = usePipe ? ['ignore', 'ignore', 'ignore', 'pipe', 'pipe'] : ['pipe', 'pipe', 'pipe'];
    const chromeProcess = childProcess.spawn(
        chromeExecutable,
        chromeArguments,
        {
          // On non-windows platforms, `detached: false` makes child process a leader of a new
          // process group, making it possible to kill child process tree with `.kill(-pid)` command.
          // @see https://nodejs.org/api/child_process.html#child_process_options_detached
          detached: process.platform !== 'win32',
          env,
          stdio
        }
    );

    if (dumpio) {
      chromeProcess.stderr.pipe(process.stderr);
      chromeProcess.stdout.pipe(process.stdout);
    }

    let chromeClosed = false;
    const waitForChromeToClose = new Promise((fulfill, reject) => {
      chromeProcess.once('exit', () => {
        chromeClosed = true;
        // Cleanup as processes exit.
        if (temporaryUserDataDir) {
          removeFolderAsync(temporaryUserDataDir)
              .then(() => fulfill())
              .catch(err => console.error(err));
        } else {
          fulfill();
        }
      });
    });

    const listeners = [ helper.addEventListener(process, 'exit', killChrome) ];
    if (handleSIGINT)
      listeners.push(helper.addEventListener(process, 'SIGINT', () => { killChrome(); process.exit(130); }));
    if (handleSIGTERM)
      listeners.push(helper.addEventListener(process, 'SIGTERM', gracefullyCloseChrome));
    if (handleSIGHUP)
      listeners.push(helper.addEventListener(process, 'SIGHUP', gracefullyCloseChrome));
    /** @type {?Connection} */
    let connection = null;
    try {
      if (!usePipe) {
        const browserWSEndpoint = await waitForWSEndpoint(chromeProcess, timeout, this._preferredRevision);
        const transport = await WebSocketTransport.create(browserWSEndpoint);
        connection = new Connection(browserWSEndpoint, transport, slowMo);
      } else {
        const transport = new PipeTransport(/** @type {!NodeJS.WritableStream} */(chromeProcess.stdio[3]), /** @type {!NodeJS.ReadableStream} */ (chromeProcess.stdio[4]));
        connection = new Connection('', transport, slowMo);
      }
      const browser = await Browser.create(connection, [], ignoreHTTPSErrors, defaultViewport, chromeProcess, gracefullyCloseChrome);
      await ensureInitialPage(browser);
      return browser;
    } catch (e) {
      killChrome();
      throw e;
    }

    /**
     * @param {!Browser} browser
     */
    async function ensureInitialPage(browser) {
      // Wait for initial page target to be created.
      if (browser.targets().find(target => target.type() === 'page'))
        return;

      let initialPageCallback;
      const initialPagePromise = new Promise(resolve => initialPageCallback = resolve);
      const listeners = [helper.addEventListener(browser, 'targetcreated', target => {
        if (target.type() === 'page')
          initialPageCallback();
      })];

      await initialPagePromise;
      helper.removeEventListeners(listeners);
    }

    /**
     * @return {Promise}
     */
    function gracefullyCloseChrome() {
      helper.removeEventListeners(listeners);
      if (temporaryUserDataDir) {
        killChrome();
      } else if (connection) {
        // Attempt to close chrome gracefully
        connection.send('Browser.close').catch(error => {
          debugError(error);
          killChrome();
        });
      }
      return waitForChromeToClose;
    }

    // This method has to be sync to be used as 'exit' event handler.
    function killChrome() {
      helper.removeEventListeners(listeners);
      if (chromeProcess.pid && !chromeProcess.killed && !chromeClosed) {
        // Force kill chrome.
        try {
          if (process.platform === 'win32')
            childProcess.execSync(`taskkill /pid ${chromeProcess.pid} /T /F`);
          else
            process.kill(-chromeProcess.pid, 'SIGKILL');
        } catch (e) {
          // the process might have already stopped
        }
      }
      // Attempt to remove temporary profile directory to avoid littering.
      try {
        removeFolder.sync(temporaryUserDataDir);
      } catch (e) { }
    }
  }

  /**
   * @param {!ChromeArgOptions=} options
   * @return {!Array<string>}
   */
  defaultArgs(options = {}) {
    const {
      devtools = false,
      headless = !devtools,
      args = [],
      userDataDir = null
    } = options;
    const chromeArguments = [...DEFAULT_ARGS];
    if (userDataDir)
      chromeArguments.push(`--user-data-dir=${userDataDir}`);
    if (devtools)
      chromeArguments.push('--auto-open-devtools-for-tabs');
    if (headless) {
      chromeArguments.push(
          '--headless',
          '--hide-scrollbars',
          '--mute-audio'
      );
      if (os.platform() === 'win32')
        chromeArguments.push('--disable-gpu');
    }
    if (args.every(arg => arg.startsWith('-')))
      chromeArguments.push('about:blank');
    chromeArguments.push(...args);
    return chromeArguments;
  }

  /**
   * @return {string}
   */
  executablePath() {
    return this._resolveExecutablePath().executablePath;
  }

  /**
   * @param {!(BrowserOptions & {browserWSEndpoint: string})} options
   * @return {!Promise<!Browser>}
   */
  async connect(options) {
    const {
      browserWSEndpoint,
      ignoreHTTPSErrors = false,
      defaultViewport = {width: 800, height: 600},
      slowMo = 0,
    } = options;
    const transport = await WebSocketTransport.create(browserWSEndpoint);
    const connection = new Connection(browserWSEndpoint, transport, slowMo);
    const {browserContextIds} = await connection.send('Target.getBrowserContexts');
    return Browser.create(connection, browserContextIds, ignoreHTTPSErrors, defaultViewport, null, () => connection.send('Browser.close').catch(debugError));
  }

  /**
   * @return {{executablePath: string, missingText: ?string}}
   */
  _resolveExecutablePath() {
    const browserFetcher = new BrowserFetcher(this._projectRoot);
    // puppeteer-core doesn't take into account PUPPETEER_* env variables.
    if (!this._isPuppeteerCore) {
      const executablePath = process.env['PUPPETEER_EXECUTABLE_PATH'];
      if (executablePath) {
        const missingText = !fs.existsSync(executablePath) ? 'Tried to use PUPPETEER_EXECUTABLE_PATH env variable to launch browser but did not find any executable at: ' + executablePath : null;
        return { executablePath, missingText };
      }
      const revision = process.env['PUPPETEER_CHROMIUM_REVISION'];
      if (revision) {
        const revisionInfo = browserFetcher.revisionInfo(revision);
        const missingText = !revisionInfo.local ? 'Tried to use PUPPETEER_CHROMIUM_REVISION env variable to launch browser but did not find executable at: ' + revisionInfo.executablePath : null;
        return {executablePath: revisionInfo.executablePath, missingText};
      }
    }
    const revisionInfo = browserFetcher.revisionInfo(this._preferredRevision);
    const missingText = !revisionInfo.local ? `Chromium revision is not downloaded. Run "npm install" or "yarn install"` : null;
    return {executablePath: revisionInfo.executablePath, missingText};
  }

}

/**
 * @param {!Puppeteer.ChildProcess} chromeProcess
 * @param {number} timeout
 * @param {string} preferredRevision
 * @return {!Promise<string>}
 */
function waitForWSEndpoint(chromeProcess, timeout, preferredRevision) {
  return new Promise((resolve, reject) => {
    const rl = readline.createInterface({ input: chromeProcess.stderr });
    let stderr = '';
    const listeners = [
      helper.addEventListener(rl, 'line', onLine),
      helper.addEventListener(rl, 'close', () => onClose()),
      helper.addEventListener(chromeProcess, 'exit', () => onClose()),
      helper.addEventListener(chromeProcess, 'error', error => onClose(error))
    ];
    const timeoutId = timeout ? setTimeout(onTimeout, timeout) : 0;

    /**
     * @param {!Error=} error
     */
    function onClose(error) {
      cleanup();
      reject(new Error([
        'Failed to launch chrome!' + (error ? ' ' + error.message : ''),
        stderr,
        '',
        'TROUBLESHOOTING: https://github.com/GoogleChrome/puppeteer/blob/master/docs/troubleshooting.md',
        '',
      ].join('\n')));
    }

    function onTimeout() {
      cleanup();
      reject(new TimeoutError(`Timed out after ${timeout} ms while trying to connect to Chrome! The only Chrome revision guaranteed to work is r${preferredRevision}`));
    }

    /**
     * @param {string} line
     */
    function onLine(line) {
      stderr += line + '\n';
      const match = line.match(/^DevTools listening on (ws:\/\/.*)$/);
      if (!match)
        return;
      cleanup();
      resolve(match[1]);
    }

    function cleanup() {
      if (timeoutId)
        clearTimeout(timeoutId);
      helper.removeEventListeners(listeners);
    }
  });
}

/**
 * @typedef {Object} ChromeArgOptions
 * @property {boolean=} headless
 * @property {Array<string>=} args
 * @property {string=} userDataDir
 * @property {boolean=} devtools
 */

/**
 * @typedef {Object} LaunchOptions
 * @property {string=} executablePath
 * @property {boolean=} ignoreDefaultArgs
 * @property {boolean=} handleSIGINT
 * @property {boolean=} handleSIGTERM
 * @property {boolean=} handleSIGHUP
 * @property {number=} timeout
 * @property {boolean=} dumpio
 * @property {!Object<string, string | undefined>=} env
 * @property {boolean=} pipe
 */

/**
 * @typedef {Object} BrowserOptions
 * @property {boolean=} ignoreHTTPSErrors
 * @property {(?Puppeteer.Viewport)=} defaultViewport
 * @property {number=} slowMo
 */


module.exports = Launcher;