/**
 * 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.
 */

import { assert } from './assert.js';
import { helper } from './helper.js';
import { Target } from './Target.js';
import { EventEmitter } from './EventEmitter.js';
import { Connection, ConnectionEmittedEvents } from './Connection.js';
import { Protocol } from 'devtools-protocol';
import { Page } from './Page.js';
import { ChildProcess } from 'child_process';
import { Viewport } from './PuppeteerViewport.js';

type BrowserCloseCallback = () => Promise<void> | void;

/**
 * @public
 */
export interface WaitForTargetOptions {
  /**
   * Maximum wait time in milliseconds. Pass `0` to disable the timeout.
   * @defaultValue 30 seconds.
   */
  timeout?: number;
}

/**
 * All the events a {@link Browser | browser instance} may emit.
 *
 * @public
 */
export const enum BrowserEmittedEvents {
  /**
   * Emitted when Puppeteer gets disconnected from the Chromium instance. This
   * might happen because of one of the following:
   *
   * - Chromium is closed or crashed
   *
   * - The {@link Browser.disconnect | browser.disconnect } method was called.
   */
  Disconnected = 'disconnected',

  /**
   * Emitted when the url of a target changes. Contains a {@link Target} instance.
   *
   * @remarks
   *
   * Note that this includes target changes in incognito browser contexts.
   */
  TargetChanged = 'targetchanged',

  /**
   * Emitted when a target is created, for example when a new page is opened by
   * {@link https://developer.mozilla.org/en-US/docs/Web/API/Window/open | window.open}
   * or by {@link Browser.newPage | browser.newPage}
   *
   * Contains a {@link Target} instance.
   *
   * @remarks
   *
   * Note that this includes target creations in incognito browser contexts.
   */
  TargetCreated = 'targetcreated',
  /**
   * Emitted when a target is destroyed, for example when a page is closed.
   * Contains a {@link Target} instance.
   *
   * @remarks
   *
   * Note that this includes target destructions in incognito browser contexts.
   */
  TargetDestroyed = 'targetdestroyed',
}

/**
 * A Browser is created when Puppeteer connects to a Chromium instance, either through
 * {@link Puppeteer.launch} or {@link Puppeteer.connect}.
 *
 * @remarks
 *
 * The Browser class extends from Puppeteer's {@link EventEmitter} class and will
 * emit various events which are documented in the {@link BrowserEmittedEvents} enum.
 *
 * @example
 *
 * An example of using a {@link Browser} to create a {@link Page}:
 * ```js
 * const puppeteer = require('puppeteer');
 *
 * (async () => {
 *   const browser = await puppeteer.launch();
 *   const page = await browser.newPage();
 *   await page.goto('https://example.com');
 *   await browser.close();
 * })();
 * ```
 *
 * @example
 *
 * An example of disconnecting from and reconnecting to a {@link Browser}:
 * ```js
 * const puppeteer = require('puppeteer');
 *
 * (async () => {
 *   const browser = await puppeteer.launch();
 *   // Store the endpoint to be able to reconnect to Chromium
 *   const browserWSEndpoint = browser.wsEndpoint();
 *   // Disconnect puppeteer from Chromium
 *   browser.disconnect();
 *
 *   // Use the endpoint to reestablish a connection
 *   const browser2 = await puppeteer.connect({browserWSEndpoint});
 *   // Close Chromium
 *   await browser2.close();
 * })();
 * ```
 *
 * @public
 */
export class Browser extends EventEmitter {
  /**
   * @internal
   */
  static async create(
    connection: Connection,
    contextIds: string[],
    ignoreHTTPSErrors: boolean,
    defaultViewport?: Viewport,
    process?: ChildProcess,
    closeCallback?: BrowserCloseCallback
  ): Promise<Browser> {
    const browser = new Browser(
      connection,
      contextIds,
      ignoreHTTPSErrors,
      defaultViewport,
      process,
      closeCallback
    );
    await connection.send('Target.setDiscoverTargets', { discover: true });
    return browser;
  }
  private _ignoreHTTPSErrors: boolean;
  private _defaultViewport?: Viewport;
  private _process?: ChildProcess;
  private _connection: Connection;
  private _closeCallback: BrowserCloseCallback;
  private _defaultContext: BrowserContext;
  private _contexts: Map<string, BrowserContext>;
  /**
   * @internal
   * Used in Target.ts directly so cannot be marked private.
   */
  _targets: Map<string, Target>;

  /**
   * @internal
   */
  constructor(
    connection: Connection,
    contextIds: string[],
    ignoreHTTPSErrors: boolean,
    defaultViewport?: Viewport,
    process?: ChildProcess,
    closeCallback?: BrowserCloseCallback
  ) {
    super();
    this._ignoreHTTPSErrors = ignoreHTTPSErrors;
    this._defaultViewport = defaultViewport;
    this._process = process;
    this._connection = connection;
    this._closeCallback = closeCallback || function (): void {};

    this._defaultContext = new BrowserContext(this._connection, this, null);
    this._contexts = new Map();
    for (const contextId of contextIds)
      this._contexts.set(
        contextId,
        new BrowserContext(this._connection, this, contextId)
      );

    this._targets = new Map();
    this._connection.on(ConnectionEmittedEvents.Disconnected, () =>
      this.emit(BrowserEmittedEvents.Disconnected)
    );
    this._connection.on('Target.targetCreated', this._targetCreated.bind(this));
    this._connection.on(
      'Target.targetDestroyed',
      this._targetDestroyed.bind(this)
    );
    this._connection.on(
      'Target.targetInfoChanged',
      this._targetInfoChanged.bind(this)
    );
  }

  /**
   * The spawned browser process. Returns `null` if the browser instance was created with
   * {@link Puppeteer.connect}.
   */
  process(): ChildProcess | null {
    return this._process;
  }

  /**
   * Creates a new incognito browser context. This won't share cookies/cache with other
   * browser contexts.
   *
   * @example
   * ```js
   * (async () => {
   *  const browser = await puppeteer.launch();
   *   // Create a new incognito browser context.
   *   const context = await browser.createIncognitoBrowserContext();
   *   // Create a new page in a pristine context.
   *   const page = await context.newPage();
   *   // Do stuff
   *   await page.goto('https://example.com');
   * })();
   * ```
   */
  async createIncognitoBrowserContext(): Promise<BrowserContext> {
    const { browserContextId } = await this._connection.send(
      'Target.createBrowserContext'
    );
    const context = new BrowserContext(
      this._connection,
      this,
      browserContextId
    );
    this._contexts.set(browserContextId, context);
    return context;
  }

  /**
   * Returns an array of all open browser contexts. In a newly created browser, this will
   * return a single instance of {@link BrowserContext}.
   */
  browserContexts(): BrowserContext[] {
    return [this._defaultContext, ...Array.from(this._contexts.values())];
  }

  /**
   * Returns the default browser context. The default browser context cannot be closed.
   */
  defaultBrowserContext(): BrowserContext {
    return this._defaultContext;
  }

  /**
   * @internal
   * Used by BrowserContext directly so cannot be marked private.
   */
  async _disposeContext(contextId?: string): Promise<void> {
    await this._connection.send('Target.disposeBrowserContext', {
      browserContextId: contextId || undefined,
    });
    this._contexts.delete(contextId);
  }

  private async _targetCreated(
    event: Protocol.Target.TargetCreatedEvent
  ): Promise<void> {
    const targetInfo = event.targetInfo;
    const { browserContextId } = targetInfo;
    const context =
      browserContextId && this._contexts.has(browserContextId)
        ? this._contexts.get(browserContextId)
        : this._defaultContext;

    const target = new Target(
      targetInfo,
      context,
      () => this._connection.createSession(targetInfo),
      this._ignoreHTTPSErrors,
      this._defaultViewport
    );
    assert(
      !this._targets.has(event.targetInfo.targetId),
      'Target should not exist before targetCreated'
    );
    this._targets.set(event.targetInfo.targetId, target);

    if (await target._initializedPromise) {
      this.emit(BrowserEmittedEvents.TargetCreated, target);
      context.emit(BrowserContextEmittedEvents.TargetCreated, target);
    }
  }

  private async _targetDestroyed(event: { targetId: string }): Promise<void> {
    const target = this._targets.get(event.targetId);
    target._initializedCallback(false);
    this._targets.delete(event.targetId);
    target._closedCallback();
    if (await target._initializedPromise) {
      this.emit(BrowserEmittedEvents.TargetDestroyed, target);
      target
        .browserContext()
        .emit(BrowserContextEmittedEvents.TargetDestroyed, target);
    }
  }

  private _targetInfoChanged(
    event: Protocol.Target.TargetInfoChangedEvent
  ): void {
    const target = this._targets.get(event.targetInfo.targetId);
    assert(target, 'target should exist before targetInfoChanged');
    const previousURL = target.url();
    const wasInitialized = target._isInitialized;
    target._targetInfoChanged(event.targetInfo);
    if (wasInitialized && previousURL !== target.url()) {
      this.emit(BrowserEmittedEvents.TargetChanged, target);
      target
        .browserContext()
        .emit(BrowserContextEmittedEvents.TargetChanged, target);
    }
  }

  /**
   * The browser websocket endpoint which can be used as an argument to
   * {@link Puppeteer.connect}.
   *
   * @returns The Browser websocket url.
   *
   * @remarks
   *
   * The format is `ws://${host}:${port}/devtools/browser/<id>`.
   *
   * You can find the `webSocketDebuggerUrl` from `http://${host}:${port}/json/version`.
   * Learn more about the
   * {@link https://chromedevtools.github.io/devtools-protocol | devtools protocol} and
   * the {@link
   * https://chromedevtools.github.io/devtools-protocol/#how-do-i-access-the-browser-target
   * | browser endpoint}.
   */
  wsEndpoint(): string {
    return this._connection.url();
  }

  /**
   * Creates a {@link Page} in the default browser context.
   */
  async newPage(): Promise<Page> {
    return this._defaultContext.newPage();
  }

  /**
   * @internal
   * Used by BrowserContext directly so cannot be marked private.
   */
  async _createPageInContext(contextId?: string): Promise<Page> {
    const { targetId } = await this._connection.send('Target.createTarget', {
      url: 'about:blank',
      browserContextId: contextId || undefined,
    });
    const target = await this._targets.get(targetId);
    assert(
      await target._initializedPromise,
      'Failed to create target for page'
    );
    const page = await target.page();
    return page;
  }

  /**
   * All active targets inside the Browser. In case of multiple browser contexts, returns
   * an array with all the targets in all browser contexts.
   */
  targets(): Target[] {
    return Array.from(this._targets.values()).filter(
      (target) => target._isInitialized
    );
  }

  /**
   * The target associated with the browser.
   */
  target(): Target {
    return this.targets().find((target) => target.type() === 'browser');
  }

  /**
   * Searches for a target in all browser contexts.
   *
   * @param predicate - A function to be run for every target.
   * @returns The first target found that matches the `predicate` function.
   *
   * @example
   *
   * An example of finding a target for a page opened via `window.open`:
   * ```js
   * await page.evaluate(() => window.open('https://www.example.com/'));
   * const newWindowTarget = await browser.waitForTarget(target => target.url() === 'https://www.example.com/');
   * ```
   */
  async waitForTarget(
    predicate: (x: Target) => boolean,
    options: WaitForTargetOptions = {}
  ): Promise<Target> {
    const { timeout = 30000 } = options;
    const existingTarget = this.targets().find(predicate);
    if (existingTarget) return existingTarget;
    let resolve;
    const targetPromise = new Promise<Target>((x) => (resolve = x));
    this.on(BrowserEmittedEvents.TargetCreated, check);
    this.on(BrowserEmittedEvents.TargetChanged, check);
    try {
      if (!timeout) return await targetPromise;
      return await helper.waitWithTimeout<Target>(
        targetPromise,
        'target',
        timeout
      );
    } finally {
      this.removeListener(BrowserEmittedEvents.TargetCreated, check);
      this.removeListener(BrowserEmittedEvents.TargetChanged, check);
    }

    function check(target: Target): void {
      if (predicate(target)) resolve(target);
    }
  }

  /**
   * An array of all open pages inside the Browser.
   *
   * @remarks
   *
   * In case of multiple browser contexts, returns an array with all the pages in all
   * browser contexts. Non-visible pages, such as `"background_page"`, will not be listed
   * here. You can find them using {@link Target.page}.
   */
  async pages(): Promise<Page[]> {
    const contextPages = await Promise.all(
      this.browserContexts().map((context) => context.pages())
    );
    // Flatten array.
    return contextPages.reduce((acc, x) => acc.concat(x), []);
  }

  /**
   * A string representing the browser name and version.
   *
   * @remarks
   *
   * For headless Chromium, this is similar to `HeadlessChrome/61.0.3153.0`. For
   * non-headless, this is similar to `Chrome/61.0.3153.0`.
   *
   * The format of browser.version() might change with future releases of Chromium.
   */
  async version(): Promise<string> {
    const version = await this._getVersion();
    return version.product;
  }

  /**
   * The browser's original user agent. Pages can override the browser user agent with
   * {@link Page.setUserAgent}.
   */
  async userAgent(): Promise<string> {
    const version = await this._getVersion();
    return version.userAgent;
  }

  /**
   * Closes Chromium and all of its pages (if any were opened). The {@link Browser} object
   * itself is considered to be disposed and cannot be used anymore.
   */
  async close(): Promise<void> {
    await this._closeCallback.call(null);
    this.disconnect();
  }

  /**
   * Disconnects Puppeteer from the browser, but leaves the Chromium process running.
   * After calling `disconnect`, the {@link Browser} object is considered disposed and
   * cannot be used anymore.
   */
  disconnect(): void {
    this._connection.dispose();
  }

  /**
   * Indicates that the browser is connected.
   */
  isConnected(): boolean {
    return !this._connection._closed;
  }

  private _getVersion(): Promise<Protocol.Browser.GetVersionResponse> {
    return this._connection.send('Browser.getVersion');
  }
}

export const enum BrowserContextEmittedEvents {
  /**
   * Emitted when the url of a target inside the browser context changes.
   * Contains a {@link Target} instance.
   */
  TargetChanged = 'targetchanged',

  /**
   * Emitted when a target is created within the browser context, for example
   * when a new page is opened by
   * {@link https://developer.mozilla.org/en-US/docs/Web/API/Window/open | window.open}
   * or by {@link BrowserContext.newPage | browserContext.newPage}
   *
   * Contains a {@link Target} instance.
   */
  TargetCreated = 'targetcreated',
  /**
   * Emitted when a target is destroyed within the browser context, for example
   * when a page is closed. Contains a {@link Target} instance.
   */
  TargetDestroyed = 'targetdestroyed',
}

/**
 * BrowserContexts provide a way to operate multiple independent browser
 * sessions. When a browser is launched, it has a single BrowserContext used by
 * default. The method {@link Browser.newPage | Browser.newPage} creates a page
 * in the default browser context.
 *
 * @remarks
 *
 * The Browser class extends from Puppeteer's {@link EventEmitter} class and
 * will emit various events which are documented in the
 * {@link BrowserContextEmittedEvents} enum.
 *
 * If a page opens another page, e.g. with a `window.open` call, the popup will
 * belong to the parent page's browser context.
 *
 * Puppeteer allows creation of "incognito" browser contexts with
 * {@link Browser.createIncognitoBrowserContext | Browser.createIncognitoBrowserContext}
 * method. "Incognito" browser contexts don't write any browsing data to disk.
 *
 * @example
 * ```js
 * // Create a new incognito browser context
 * const context = await browser.createIncognitoBrowserContext();
 * // Create a new page inside context.
 * const page = await context.newPage();
 * // ... do stuff with page ...
 * await page.goto('https://example.com');
 * // Dispose context once it's no longer needed.
 * await context.close();
 * ```
 */
export class BrowserContext extends EventEmitter {
  private _connection: Connection;
  private _browser: Browser;
  private _id?: string;

  /**
   * @internal
   */
  constructor(connection: Connection, browser: Browser, contextId?: string) {
    super();
    this._connection = connection;
    this._browser = browser;
    this._id = contextId;
  }

  /**
   * An array of all active targets inside the browser context.
   */
  targets(): Target[] {
    return this._browser
      .targets()
      .filter((target) => target.browserContext() === this);
  }

  /**
   * This searches for a target in this specific browser context.
   *
   * @example
   * An example of finding a target for a page opened via `window.open`:
   * ```js
   * await page.evaluate(() => window.open('https://www.example.com/'));
   * const newWindowTarget = await browserContext.waitForTarget(target => target.url() === 'https://www.example.com/');
   * ```
   *
   * @param predicate - A function to be run for every target
   * @param options - An object of options. Accepts a timout,
   * which is the maximum wait time in milliseconds.
   * Pass `0` to disable the timeout. Defaults to 30 seconds.
   * @returns Promise which resolves to the first target found
   * that matches the `predicate` function.
   */
  waitForTarget(
    predicate: (x: Target) => boolean,
    options: { timeout?: number } = {}
  ): Promise<Target> {
    return this._browser.waitForTarget(
      (target) => target.browserContext() === this && predicate(target),
      options
    );
  }

  /**
   * An array of all pages inside the browser context.
   *
   * @returns Promise which resolves to an array of all open pages.
   * Non visible pages, such as `"background_page"`, will not be listed here.
   * You can find them using {@link Target.page | the target page}.
   */
  async pages(): Promise<Page[]> {
    const pages = await Promise.all(
      this.targets()
        .filter((target) => target.type() === 'page')
        .map((target) => target.page())
    );
    return pages.filter((page) => !!page);
  }

  /**
   * Returns whether BrowserContext is incognito.
   * The default browser context is the only non-incognito browser context.
   *
   * @remarks
   * The default browser context cannot be closed.
   */
  isIncognito(): boolean {
    return !!this._id;
  }

  /**
   * @example
   * ```js
   * const context = browser.defaultBrowserContext();
   * await context.overridePermissions('https://html5demos.com', ['geolocation']);
   * ```
   *
   * @param origin - The origin to grant permissions to, e.g. "https://example.com".
   * @param permissions - An array of permissions to grant.
   * All permissions that are not listed here will be automatically denied.
   */
  async overridePermissions(
    origin: string,
    permissions: Protocol.Browser.PermissionType[]
  ): Promise<void> {
    const webPermissionToProtocol = new Map<
      string,
      Protocol.Browser.PermissionType
    >([
      ['geolocation', 'geolocation'],
      ['midi', 'midi'],
      ['notifications', 'notifications'],
      // TODO: push isn't a valid type?
      // ['push', 'push'],
      ['camera', 'videoCapture'],
      ['microphone', 'audioCapture'],
      ['background-sync', 'backgroundSync'],
      ['ambient-light-sensor', 'sensors'],
      ['accelerometer', 'sensors'],
      ['gyroscope', 'sensors'],
      ['magnetometer', 'sensors'],
      ['accessibility-events', 'accessibilityEvents'],
      ['clipboard-read', 'clipboardReadWrite'],
      ['clipboard-write', 'clipboardReadWrite'],
      ['payment-handler', 'paymentHandler'],
      // chrome-specific permissions we have.
      ['midi-sysex', 'midiSysex'],
    ]);
    permissions = permissions.map((permission) => {
      const protocolPermission = webPermissionToProtocol.get(permission);
      if (!protocolPermission)
        throw new Error('Unknown permission: ' + permission);
      return protocolPermission;
    });
    await this._connection.send('Browser.grantPermissions', {
      origin,
      browserContextId: this._id || undefined,
      permissions,
    });
  }

  /**
   * Clears all permission overrides for the browser context.
   *
   * @example
   * ```js
   * const context = browser.defaultBrowserContext();
   * context.overridePermissions('https://example.com', ['clipboard-read']);
   * // do stuff ..
   * context.clearPermissionOverrides();
   * ```
   */
  async clearPermissionOverrides(): Promise<void> {
    await this._connection.send('Browser.resetPermissions', {
      browserContextId: this._id || undefined,
    });
  }

  /**
   * Creates a new page in the browser context.
   */
  newPage(): Promise<Page> {
    return this._browser._createPageInContext(this._id);
  }

  /**
   * The browser this browser context belongs to.
   */
  browser(): Browser {
    return this._browser;
  }

  /**
   * Closes the browser context. All the targets that belong to the browser context
   * will be closed.
   *
   * @remarks
   * Only incognito browser contexts can be closed.
   */
  async close(): Promise<void> {
    assert(this._id, 'Non-incognito profiles cannot be closed!');
    await this._browser._disposeContext(this._id);
  }
}