text: // Licensed to the Software Freedom Conservancy (SFC) under one
  // or more contributor license agreements.  See the NOTICE file
  // distributed with this work for additional information
  // regarding copyright ownership.  The SFC licenses this file
  // to you 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.
  
  /**
   * @fileoverview The heart of the WebDriver JavaScript API.
   */
  
  'use strict'
  
  const by = require('./by')
  const { RelativeBy } = require('./by')
  const command = require('./command')
  const error = require('./error')
  const input = require('./input')
  const logging = require('./logging')
  const promise = require('./promise')
  const Symbols = require('./symbols')
  const cdp = require('../devtools/CDPConnection')
  const WebSocket = require('ws')
  const http = require('../http/index')
  const fs = require('fs')
  const { Capabilities } = require('./capabilities')
  const path = require('path')
  const { NoSuchElementError } = require('./error')
  const cdpTargets = ['page', 'browser']
  
  // Capability names that are defined in the W3C spec.
  const W3C_CAPABILITY_NAMES = new Set([
    'acceptInsecureCerts',
    'browserName',
    'browserVersion',
    'pageLoadStrategy',
    'platformName',
    'proxy',
    'setWindowRect',
    'strictFileInteractability',
    'timeouts',
    'unhandledPromptBehavior',
    'webSocketUrl',
  ])
  
  /**
   * Defines a condition for use with WebDriver's {@linkplain WebDriver#wait wait
   * command}.
   *
   * @template OUT
   */
  class Condition {
    /**
     * @param {string} message A descriptive error message. Should complete the
     *     sentence "Waiting [...]"
     * @param {function(!WebDriver): OUT} fn The condition function to
     *     evaluate on each iteration of the wait loop.
     */
    constructor(message, fn) {
      /** @private {string} */
      this.description_ = 'Waiting ' + message
  
      /** @type {function(!WebDriver): OUT} */
      this.fn = fn
    }
  
    /** @return {string} A description of this condition. */
    description() {
      return this.description_
    }
  }
  
  /**
   * Defines a condition that will result in a {@link WebElement}.
   *
   * @extends {Condition<!(WebElement|IThenable<!WebElement>)>}
   */
  class WebElementCondition extends Condition {
    /**
     * @param {string} message A descriptive error message. Should complete the
     *     sentence "Waiting [...]"
     * @param {function(!WebDriver): !(WebElement|IThenable<!WebElement>)}
     *     fn The condition function to evaluate on each iteration of the wait
     *     loop.
     */
    constructor(message, fn) {
      super(message, fn)
    }
  }
  
  //////////////////////////////////////////////////////////////////////////////
  //
  //  WebDriver
  //
  //////////////////////////////////////////////////////////////////////////////
  
  /**
   * Translates a command to its wire-protocol representation before passing it
   * to the given `executor` for execution.
   * @param {!command.Executor} executor The executor to use.
   * @param {!command.Command} command The command to execute.
   * @return {!Promise} A promise that will resolve with the command response.
   */
  function executeCommand(executor, command) {
    return toWireValue(command.getParameters()).then(function (parameters) {
      command.setParameters(parameters)
      return executor.execute(command)
    })
  }
  
  /**
   * Converts an object to its JSON representation in the WebDriver wire protocol.
   * When converting values of type object, the following steps will be taken:
   * <ol>
   * <li>if the object is a WebElement, the return value will be the element's
   *     server ID
   * <li>if the object defines a {@link Symbols.serialize} method, this algorithm
   *     will be recursively applied to the object's serialized representation
   * <li>if the object provides a "toJSON" function, this algorithm will
   *     recursively be applied to the result of that function
   * <li>otherwise, the value of each key will be recursively converted according
   *     to the rules above.
   * </ol>
   *
   * @param {*} obj The object to convert.
   * @return {!Promise<?>} A promise that will resolve to the input value's JSON
   *     representation.
   */
  async function toWireValue(obj) {
    let value = await Promise.resolve(obj)
    if (value === void 0 || value === null) {
      return value
    }
  
    if (
      typeof value === 'boolean' ||
      typeof value === 'number' ||
      typeof value === 'string'
    ) {
      return value
    }
  
    if (Array.isArray(value)) {
      return convertKeys(value)
    }
  
    if (typeof value === 'function') {
      return '' + value
    }
  
    if (typeof value[Symbols.serialize] === 'function') {
      return toWireValue(value[Symbols.serialize]())
    } else if (typeof value.toJSON === 'function') {
      return toWireValue(value.toJSON())
    }
    return convertKeys(value)
  }
  
  async function convertKeys(obj) {
    const isArray = Array.isArray(obj)
    const numKeys = isArray ? obj.length : Object.keys(obj).length
    const ret = isArray ? new Array(numKeys) : {}
    if (!numKeys) {
      return ret
    }
  
    async function forEachKey(obj, fn) {
      if (Array.isArray(obj)) {
        for (let i = 0, n = obj.length; i < n; i++) {
          await fn(obj[i], i)
        }
      } else {
        for (let key in obj) {
          await fn(obj[key], key)
        }
      }
    }
  
    await forEachKey(obj, async function (value, key) {
      ret[key] = await toWireValue(value)
    })
  
    return ret
  }
  
  /**
   * Converts a value from its JSON representation according to the WebDriver wire
   * protocol. Any JSON object that defines a WebElement ID will be decoded to a
   * {@link WebElement} object. All other values will be passed through as is.
   *
   * @param {!WebDriver} driver The driver to use as the parent of any unwrapped
   *     {@link WebElement} values.
   * @param {*} value The value to convert.
   * @return {*} The converted value.
   */
  function fromWireValue(driver, value) {
    if (Array.isArray(value)) {
      value = value.map((v) => fromWireValue(driver, v))
    } else if (WebElement.isId(value)) {
      let id = WebElement.extractId(value)
      value = new WebElement(driver, id)
    } else if (value && typeof value === 'object') {
      let result = {}
      for (let key in value) {
        if (Object.prototype.hasOwnProperty.call(value, key)) {
          result[key] = fromWireValue(driver, value[key])
        }
      }
      value = result
    }
    return value
  }
  
  /**
   * Resolves a wait message from either a function or a string.
   * @param {(string|Function)=} message An optional message to use if the wait times out.
   * @return {string} The resolved message
   */
  function resolveWaitMessage(message) {
    return message
      ? `${typeof message === 'function' ? message() : message}\n`
      : ''
  }
  
  /**
   * Structural interface for a WebDriver client.
   *
   * @record
   */
  class IWebDriver {
    /**
     * Executes the provided {@link command.Command} using this driver's
     * {@link command.Executor}.
     *
     * @param {!command.Command} command The command to schedule.
     * @return {!Promise<T>} A promise that will be resolved with the command
     *     result.
     * @template T
     */
    execute(command) {} // eslint-disable-line
  
    /**
     * Sets the {@linkplain input.FileDetector file detector} that should be
     * used with this instance.
     * @param {input.FileDetector} detector The detector to use or `null`.
     */
    setFileDetector(detector) {} // eslint-disable-line
  
    /**
     * @return {!command.Executor} The command executor used by this instance.
     */
    getExecutor() {}
  
    /**
     * @return {!Promise<!Session>} A promise for this client's session.
     */
    getSession() {}
  
    /**
     * @return {!Promise<!Capabilities>} A promise that will resolve with
     *     the this instance's capabilities.
     */
    getCapabilities() {}
  
    /**
     * Terminates the browser session. After calling quit, this instance will be
     * invalidated and may no longer be used to issue commands against the
     * browser.
     *
     * @return {!Promise<void>} A promise that will be resolved when the
     *     command has completed.
     */
    quit() {}
  
    /**
     * Creates a new action sequence using this driver. The sequence will not be
     * submitted for execution until
     * {@link ./input.Actions#perform Actions.perform()} is called.
     *
     * @param {{async: (boolean|undefined),
     *          bridge: (boolean|undefined)}=} options Configuration options for
     *     the action sequence (see {@link ./input.Actions Actions} documentation
     *     for details).
     * @return {!input.Actions} A new action sequence for this instance.
     */
    actions(options) {} // eslint-disable-line
  
    /**
     * Executes a snippet of JavaScript in the context of the currently selected
     * frame or window. The script fragment will be executed as the body of an
     * anonymous function. If the script is provided as a function object, that
     * function will be converted to a string for injection into the target
     * window.
     *
     * Any arguments provided in addition to the script will be included as script
     * arguments and may be referenced using the `arguments` object. Arguments may
     * be a boolean, number, string, or {@linkplain WebElement}. Arrays and
     * objects may also be used as script arguments as long as each item adheres
     * to the types previously mentioned.
     *
     * The script may refer to any variables accessible from the current window.
     * Furthermore, the script will execute in the window's context, thus
     * `document` may be used to refer to the current document. Any local
     * variables will not be available once the script has finished executing,
     * though global variables will persist.
     *
     * If the script has a return value (i.e. if the script contains a return
     * statement), then the following steps will be taken for resolving this
     * functions return value:
     *
     * - For a HTML element, the value will resolve to a {@linkplain WebElement}
     * - Null and undefined return values will resolve to null</li>
     * - Booleans, numbers, and strings will resolve as is</li>
     * - Functions will resolve to their string representation</li>
     * - For arrays and objects, each member item will be converted according to
     *     the rules above
     *
     * @param {!(string|Function)} script The script to execute.
     * @param {...*} args The arguments to pass to the script.
     * @return {!IThenable<T>} A promise that will resolve to the
     *    scripts return value.
     * @template T
     */
    executeScript(script, ...args) {} // eslint-disable-line
  
    /**
     * Executes a snippet of asynchronous JavaScript in the context of the
     * currently selected frame or window. The script fragment will be executed as
     * the body of an anonymous function. If the script is provided as a function
     * object, that function will be converted to a string for injection into the
     * target window.
     *
     * Any arguments provided in addition to the script will be included as script
     * arguments and may be referenced using the `arguments` object. Arguments may
     * be a boolean, number, string, or {@linkplain WebElement}. Arrays and
     * objects may also be used as script arguments as long as each item adheres
     * to the types previously mentioned.
     *
     * Unlike executing synchronous JavaScript with {@link #executeScript},
     * scripts executed with this function must explicitly signal they are
     * finished by invoking the provided callback. This callback will always be
     * injected into the executed function as the last argument, and thus may be
     * referenced with  `arguments[arguments.length - 1]`. The following steps
     * will be taken for resolving this functions return value against the first
     * argument to the script's callback function:
     *
     * - For a HTML element, the value will resolve to a {@link WebElement}
     * - Null and undefined return values will resolve to null
     * - Booleans, numbers, and strings will resolve as is
     * - Functions will resolve to their string representation
     * - For arrays and objects, each member item will be converted according to
     *     the rules above
     *
     * __Example #1:__ Performing a sleep that is synchronized with the currently
     * selected window:
     *
     *     var start = new Date().getTime();
     *     driver.executeAsyncScript(
     *         'window.setTimeout(arguments[arguments.length - 1], 500);').
     *         then(function() {
     *           console.log(
     *               'Elapsed time: ' + (new Date().getTime() - start) + ' ms');
     *         });
     *
     * __Example #2:__ Synchronizing a test with an AJAX application:
     *
     *     var button = driver.findElement(By.id('compose-button'));
     *     button.click();
     *     driver.executeAsyncScript(
     *         'var callback = arguments[arguments.length - 1];' +
     *         'mailClient.getComposeWindowWidget().onload(callback);');
     *     driver.switchTo().frame('composeWidget');
     *     driver.findElement(By.id('to')).sendKeys('dog@example.com');
     *
     * __Example #3:__ Injecting a XMLHttpRequest and waiting for the result. In
     * this example, the inject script is specified with a function literal. When
     * using this format, the function is converted to a string for injection, so
     * it should not reference any symbols not defined in the scope of the page
     * under test.
     *
     *     driver.executeAsyncScript(function() {
     *       var callback = arguments[arguments.length - 1];
     *       var xhr = new XMLHttpRequest();
     *       xhr.open("GET", "/resource/data.json", true);
     *       xhr.onreadystatechange = function() {
     *         if (xhr.readyState == 4) {
     *           callback(xhr.responseText);
     *         }
     *       };
     *       xhr.send('');
     *     }).then(function(str) {
     *       console.log(JSON.parse(str)['food']);
     *     });
     *
     * @param {!(string|Function)} script The script to execute.
     * @param {...*} args The arguments to pass to the script.
     * @return {!IThenable<T>} A promise that will resolve to the scripts return
     *     value.
     * @template T
     */
    executeAsyncScript(script, ...args) {} // eslint-disable-line
  
    /**
     * Waits for a condition to evaluate to a "truthy" value. The condition may be
     * specified by a {@link Condition}, as a custom function, or as any
     * promise-like thenable.
     *
     * For a {@link Condition} or function, the wait will repeatedly
     * evaluate the condition until it returns a truthy value. If any errors occur
     * while evaluating the condition, they will be allowed to propagate. In the
     * event a condition returns a {@linkplain Promise}, the polling loop will
     * wait for it to be resolved and use the resolved value for whether the
     * condition has been satisfied. The resolution time for a promise is always
     * factored into whether a wait has timed out.
     *
     * If the provided condition is a {@link WebElementCondition}, then
     * the wait will return a {@link WebElementPromise} that will resolve to the
     * element that satisfied the condition.
     *
     * _Example:_ waiting up to 10 seconds for an element to be present on the
     * page.
     *
     *     async function example() {
     *       let button =
     *           await driver.wait(until.elementLocated(By.id('foo')), 10000);
     *       await button.click();
     *     }
     *
     * @param {!(IThenable<T>|
     *           Condition<T>|
     *           function(!WebDriver): T)} condition The condition to
     *     wait on, defined as a promise, condition object, or  a function to
     *     evaluate as a condition.
     * @param {number=} timeout The duration in milliseconds, how long to wait
     *     for the condition to be true.
     * @param {(string|Function)=} message An optional message to use if the wait times out.
     * @param {number=} pollTimeout The duration in milliseconds, how long to
     *     wait between polling the condition.
     * @return {!(IThenable<T>|WebElementPromise)} A promise that will be
     *     resolved with the first truthy value returned by the condition
     *     function, or rejected if the condition times out. If the input
     *     input condition is an instance of a {@link WebElementCondition},
     *     the returned value will be a {@link WebElementPromise}.
     * @throws {TypeError} if the provided `condition` is not a valid type.
     * @template T
     */
    wait(
      condition, // eslint-disable-line
      timeout = undefined, // eslint-disable-line
      message = undefined, // eslint-disable-line
      pollTimeout = undefined // eslint-disable-line
    ) {}
  
    /**
     * Makes the driver sleep for the given amount of time.
     *
     * @param {number} ms The amount of time, in milliseconds, to sleep.
     * @return {!Promise<void>} A promise that will be resolved when the sleep has
     *     finished.
     */
    sleep(ms) {} // eslint-disable-line
  
    /**
     * Retrieves the current window handle.
     *
     * @return {!Promise<string>} A promise that will be resolved with the current
     *     window handle.
     */
    getWindowHandle() {}
  
    /**
     * Retrieves a list of all available window handles.
     *
     * @return {!Promise<!Array<string>>} A promise that will be resolved with an
     *     array of window handles.
     */
    getAllWindowHandles() {}
  
    /**
     * Retrieves the current page's source. The returned source is a representation
     * of the underlying DOM: do not expect it to be formatted or escaped in the
     * same way as the raw response sent from the web server.
     *
     * @return {!Promise<string>} A promise that will be resolved with the current
     *     page source.
     */
    getPageSource() {}
  
    /**
     * Closes the current window.
     *
     * @return {!Promise<void>} A promise that will be resolved when this command
     *     has completed.
     */
    close() {}
  
    /**
     * Navigates to the given URL.
     *
     * @param {string} url The fully qualified URL to open.
     * @return {!Promise<void>} A promise that will be resolved when the document
     *     has finished loading.
     */
    get(url) {} // eslint-disable-line
  
    /**
     * Retrieves the URL for the current page.
     *
     * @return {!Promise<string>} A promise that will be resolved with the
     *     current URL.
     */
    getCurrentUrl() {}
  
    /**
     * Retrieves the current page title.
     *
     * @return {!Promise<string>} A promise that will be resolved with the current
     *     page's title.
     */
    getTitle() {}
  
    /**
     * Locates an element on the page. If the element cannot be found, a
     * {@link error.NoSuchElementError} will be returned by the driver.
     *
     * This function should not be used to test whether an element is present on
     * the page. Rather, you should use {@link #findElements}:
     *
     *     driver.findElements(By.id('foo'))
     *         .then(found => console.log('Element found? %s', !!found.length));
     *
     * The search criteria for an element may be defined using one of the
     * factories in the {@link webdriver.By} namespace, or as a short-hand
     * {@link webdriver.By.Hash} object. For example, the following two statements
     * are equivalent:
     *
     *     var e1 = driver.findElement(By.id('foo'));
     *     var e2 = driver.findElement({id:'foo'});
     *
     * You may also provide a custom locator function, which takes as input this
     * instance and returns a {@link WebElement}, or a promise that will resolve
     * to a WebElement. If the returned promise resolves to an array of
     * WebElements, WebDriver will use the first element. For example, to find the
     * first visible link on a page, you could write:
     *
     *     var link = driver.findElement(firstVisibleLink);
     *
     *     function firstVisibleLink(driver) {
     *       var links = driver.findElements(By.tagName('a'));
     *       return promise.filter(links, function(link) {
     *         return link.isDisplayed();
     *       });
     *     }
     *
     * @param {!(by.By|Function)} locator The locator to use.
     * @return {!WebElementPromise} A WebElement that can be used to issue
     *     commands against the located element. If the element is not found, the
     *     element will be invalidated and all scheduled commands aborted.
     */
    findElement(locator) {} // eslint-disable-line
  
    /**
     * Search for multiple elements on the page. Refer to the documentation on
     * {@link #findElement(by)} for information on element locator strategies.
     *
     * @param {!(by.By|Function)} locator The locator to use.
     * @return {!Promise<!Array<!WebElement>>} A promise that will resolve to an
     *     array of WebElements.
     */
    findElements(locator) {} // eslint-disable-line
  
    /**
     * Takes a screenshot of the current page. The driver makes a best effort to
     * return a screenshot of the following, in order of preference:
     *
     * 1. Entire page
     * 2. Current window
     * 3. Visible portion of the current frame
     * 4. The entire display containing the browser
     *
     * @return {!Promise<string>} A promise that will be resolved to the
     *     screenshot as a base-64 encoded PNG.
     */
    takeScreenshot() {}
  
    /**
     * @return {!Options} The options interface for this instance.
     */
    manage() {}
  
    /**
     * @return {!Navigation} The navigation interface for this instance.
     */
    navigate() {}
  
    /**
     * @return {!TargetLocator} The target locator interface for this
     *     instance.
     */
    switchTo() {}
  
    /**
     *
     * Takes a PDF of the current page. The driver makes a best effort to
     * return a PDF based on the provided parameters.
     *
     * @param {{orientation: (string|undefined),
     *         scale: (number|undefined),
     *         background: (boolean|undefined)
     *         width: (number|undefined)
     *         height: (number|undefined)
     *         top: (number|undefined)
     *         bottom: (number|undefined)
     *         left: (number|undefined)
     *         right: (number|undefined)
     *         shrinkToFit: (boolean|undefined)
     *         pageRanges: (<Array>|undefined)}} options.
     */
    printPage(options) {} // eslint-disable-line
  }
  
  /**
   * @param {!Capabilities} capabilities A capabilities object.
   * @return {!Capabilities} A copy of the parameter capabilities, omitting
   *     capability names that are not valid W3C names.
   */
  function filterNonW3CCaps(capabilities) {
    let newCaps = new Capabilities(capabilities)
    for (let k of newCaps.keys()) {
      // Any key containing a colon is a vendor-prefixed capability.
      if (!(W3C_CAPABILITY_NAMES.has(k) || k.indexOf(':') >= 0)) {
        newCaps.delete(k)
      }
    }
    return newCaps
  }
  
  /**
   * Each WebDriver instance provides automated control over a browser session.
   *
   * @implements {IWebDriver}
   */
  class WebDriver {
    /**
     * @param {!(./session.Session|IThenable<!./session.Session>)} session Either
     *     a known session or a promise that will be resolved to a session.
     * @param {!command.Executor} executor The executor to use when sending
     *     commands to the browser.
     * @param {(function(this: void): ?)=} onQuit A function to call, if any,
     *     when the session is terminated.
     */
    constructor(session, executor, onQuit = undefined) {
      /** @private {!Promise<!Session>} */
      this.session_ = Promise.resolve(session)
  
      // If session is a rejected promise, add a no-op rejection handler.
      // This effectively hides setup errors until users attempt to interact
      // with the session.
      this.session_.catch(function () {})
  
      /** @private {!command.Executor} */
      this.executor_ = executor
  
      /** @private {input.FileDetector} */
      this.fileDetector_ = null
  
      /** @private @const {(function(this: void): ?|undefined)} */
      this.onQuit_ = onQuit
    }
  
    /**
     * Creates a new WebDriver session.
     *
     * This function will always return a WebDriver instance. If there is an error
     * creating the session, such as the aforementioned SessionNotCreatedError,
     * the driver will have a rejected {@linkplain #getSession session} promise.
     * This rejection will propagate through any subsequent commands scheduled
     * on the returned WebDriver instance.
     *
     *     let required = Capabilities.firefox();
     *     let driver = WebDriver.createSession(executor, {required});
     *
     *     // If the createSession operation failed, then this command will also
     *     // also fail, propagating the creation failure.
     *     driver.get('http://www.google.com').catch(e => console.log(e));
     *
     * @param {!command.Executor} executor The executor to create the new session
     *     with.
     * @param {!Capabilities} capabilities The desired capabilities for the new
     *     session.
     * @param {(function(this: void): ?)=} onQuit A callback to invoke when
     *    the newly created session is terminated. This should be used to clean
     *    up any resources associated with the session.
     * @return {!WebDriver} The driver for the newly created session.
     */
    static createSession(executor, capabilities, onQuit = undefined) {
      let cmd = new command.Command(command.Name.NEW_SESSION)
  
      // For OSS remote ends.
      cmd.setParameter('desiredCapabilities', capabilities)
      // For W3C remote ends.
      cmd.setParameter('capabilities', {
        alwaysMatch: filterNonW3CCaps(capabilities),
      })
  
      let session = executeCommand(executor, cmd)
      if (typeof onQuit === 'function') {
        session = session.catch((err) => {
          return Promise.resolve(onQuit.call(void 0)).then((_) => {
            throw err
          })
        })
      }
      return new this(session, executor, onQuit)
    }
  
    /** @override */
    async execute(command) {
      command.setParameter('sessionId', this.session_)
      let parameters = await toWireValue(command.getParameters())
      command.setParameters(parameters)
      let value = await this.executor_.execute(command)
      return fromWireValue(this, value)
    }
  
    /** @override */
    setFileDetector(detector) {
      this.fileDetector_ = detector
    }
  
    /** @override */
    getExecutor() {
      return this.executor_
    }
  
    /** @override */
    getSession() {
      return this.session_
    }
  
    /** @override */
    getCapabilities() {
      return this.session_.then((s) => s.getCapabilities())
    }
  
    /** @override */
    quit() {
      let result = this.execute(new command.Command(command.Name.QUIT))
      // Delete our session ID when the quit command finishes; this will allow us
      // to throw an error when attempting to use a driver post-quit.
      return promise.finally(result, () => {
        this.session_ = Promise.reject(
          new error.NoSuchSessionError(
            'This driver instance does not have a valid session ID ' +
              '(did you call WebDriver.quit()?) and may no longer be used.'
          )
        )
  
        // Only want the session rejection to bubble if accessed.
        this.session_.catch(function () {})
  
        if (this.onQuit_) {
          return this.onQuit_.call(void 0)
        }
      })
    }
  
    /** @override */
    actions(options) {
      return new input.Actions(this, options || undefined)
    }
  
    /** @override */
    executeScript(script, ...args) {
      if (typeof script === 'function') {
        script = 'return (' + script + ').apply(null, arguments);'
      }
      return this.execute(
        new command.Command(command.Name.EXECUTE_SCRIPT)
          .setParameter('script', script)
          .setParameter('args', args)
      )
    }
  
    /** @override */
    executeAsyncScript(script, ...args) {
      if (typeof script === 'function') {
        script = 'return (' + script + ').apply(null, arguments);'
      }
      return this.execute(
        new command.Command(command.Name.EXECUTE_ASYNC_SCRIPT)
          .setParameter('script', script)
          .setParameter('args', args)
      )
    }
  
    /** @override */
    wait(condition, timeout = 0, message = undefined, pollTimeout = 200) {
      if (typeof timeout !== 'number' || timeout < 0) {
        throw TypeError('timeout must be a number >= 0: ' + timeout)
      }
  
      if (typeof pollTimeout !== 'number' || pollTimeout < 0) {
        throw TypeError('pollTimeout must be a number >= 0: ' + pollTimeout)
      }
  
      if (promise.isPromise(condition)) {
        return new Promise((resolve, reject) => {
          if (!timeout) {
            resolve(condition)
            return
          }
  
          let start = Date.now()
          let timer = setTimeout(function () {
            timer = null
            try {
              let timeoutMessage = resolveWaitMessage(message)
              reject(
                new error.TimeoutError(
                  `${timeoutMessage}Timed out waiting for promise to resolve after ${
                    Date.now() - start
                  }ms`
                )
              )
            } catch (ex) {
              reject(
                new error.TimeoutError(
                  `${
                    ex.message
                  }\nTimed out waiting for promise to resolve after ${
                    Date.now() - start
                  }ms`
                )
              )
            }
          }, timeout)
          const clearTimer = () => timer && clearTimeout(timer)
  
          /** @type {!IThenable} */ condition.then(
            function (value) {
              clearTimer()
              resolve(value)
            },
            function (error) {
              clearTimer()
              reject(error)
            }
          )
        })
      }
  
      let fn = /** @type {!Function} */ (condition)
      if (condition instanceof Condition) {
        message = message || condition.description()
        fn = condition.fn
      }
  
      if (typeof fn !== 'function') {
        throw TypeError(
          'Wait condition must be a promise-like object, function, or a ' +
            'Condition object'
        )
      }
  
      const driver = this
      function evaluateCondition() {
        return new Promise((resolve, reject) => {
          try {
            resolve(fn(driver))
          } catch (ex) {
            reject(ex)
          }
        })
      }
  
      let result = new Promise((resolve, reject) => {
        const startTime = Date.now()
        const pollCondition = async () => {
          evaluateCondition().then(function (value) {
            const elapsed = Date.now() - startTime
            if (value) {
              resolve(value)
            } else if (timeout && elapsed >= timeout) {
              try {
                let timeoutMessage = resolveWaitMessage(message)
                reject(
                  new error.TimeoutError(
                    `${timeoutMessage}Wait timed out after ${elapsed}ms`
                  )
                )
              } catch (ex) {
                reject(
                  new error.TimeoutError(
                    `${ex.message}\nWait timed out after ${elapsed}ms`
                  )
                )
              }
            } else {
              setTimeout(pollCondition, pollTimeout)
            }
          }, reject)
        }
        pollCondition()
      })
  
      if (condition instanceof WebElementCondition) {
        result = new WebElementPromise(
          this,
          result.then(function (value) {
            if (!(value instanceof WebElement)) {
              throw TypeError(
                'WebElementCondition did not resolve to a WebElement: ' +
                  Object.prototype.toString.call(value)
              )
            }
            return value
          })
        )
      }
      return result
    }
  
    /** @override */
    sleep(ms) {
      return new Promise((resolve) => setTimeout(resolve, ms))
    }
  
    /** @override */
    getWindowHandle() {
      return this.execute(
        new command.Command(command.Name.GET_CURRENT_WINDOW_HANDLE)
      )
    }
  
    /** @override */
    getAllWindowHandles() {
      return this.execute(new command.Command(command.Name.GET_WINDOW_HANDLES))
    }
  
    /** @override */
    getPageSource() {
      return this.execute(new command.Command(command.Name.GET_PAGE_SOURCE))
    }
  
    /** @override */
    close() {
      return this.execute(new command.Command(command.Name.CLOSE))
    }
  
    /** @override */
    get(url) {
      return this.navigate().to(url)
    }
  
    /** @override */
    getCurrentUrl() {
      return this.execute(new command.Command(command.Name.GET_CURRENT_URL))
    }
  
    /** @override */
    getTitle() {
      return this.execute(new command.Command(command.Name.GET_TITLE))
    }
  
    /** @override */
    findElement(locator) {
      let id
      let cmd = null
  
      if (locator instanceof RelativeBy) {
        cmd = new command.Command(
          command.Name.FIND_ELEMENTS_RELATIVE
        ).setParameter('args', locator.marshall())
      } else {
        locator = by.checkedLocator(locator)
      }
  
      if (typeof locator === 'function') {
        id = this.findElementInternal_(locator, this)
        return new WebElementPromise(this, id)
      } else if (cmd === null) {
        cmd = new command.Command(command.Name.FIND_ELEMENT)
          .setParameter('using', locator.using)
          .setParameter('value', locator.value)
      }
  
      id = this.execute(cmd)
      if (locator instanceof RelativeBy) {
        return this.normalize_(id)
      } else {
        return new WebElementPromise(this, id)
      }
    }
  
    /**
     * @param {!Function} webElementPromise The webElement in unresolved state
     * @return {!Promise<!WebElement>} First single WebElement from array of resolved promises
     */
    async normalize_(webElementPromise) {
      let result = await webElementPromise
      if (result.length === 0) {
        throw new NoSuchElementError(
          'Cannot locate an element with provided parameters'
        )
      } else {
        return result[0]
      }
    }
  
    /**
     * @param {!Function} locatorFn The locator function to use.
     * @param {!(WebDriver|WebElement)} context The search context.
     * @return {!Promise<!WebElement>} A promise that will resolve to a list of
     *     WebElements.
     * @private
     */
    async findElementInternal_(locatorFn, context) {
      let result = await locatorFn(context)
      if (Array.isArray(result)) {
        result = result[0]
      }
      if (!(result instanceof WebElement)) {
        throw new TypeError('Custom locator did not return a WebElement')
      }
      return result
    }
  
    /** @override */
    async findElements(locator) {
      let cmd = null
      if (locator instanceof RelativeBy) {
        cmd = new command.Command(
          command.Name.FIND_ELEMENTS_RELATIVE
        ).setParameter('args', locator.marshall())
      } else {
        locator = by.checkedLocator(locator)
      }
  
      if (typeof locator === 'function') {
        return this.findElementsInternal_(locator, this)
      } else if (cmd === null) {
        cmd = new command.Command(command.Name.FIND_ELEMENTS)
          .setParameter('using', locator.using)
          .setParameter('value', locator.value)
      }
      try {
        let res = await this.execute(cmd)
        return Array.isArray(res) ? res : []
      } catch (ex) {
        if (ex instanceof error.NoSuchElementError) {
          return []
        }
        throw ex
      }
    }
  
    /**
     * @param {!Function} locatorFn The locator function to use.
     * @param {!(WebDriver|WebElement)} context The search context.
     * @return {!Promise<!Array<!WebElement>>} A promise that will resolve to an
     *     array of WebElements.
     * @private
     */
    async findElementsInternal_(locatorFn, context) {
      const result = await locatorFn(context)
      if (result instanceof WebElement) {
        return [result]
      }
  
      if (!Array.isArray(result)) {
        return []
      }
  
      return result.filter(function (item) {
        return item instanceof WebElement
      })
    }
  
    /** @override */
    takeScreenshot() {
      return this.execute(new command.Command(command.Name.SCREENSHOT))
    }
  
    /** @override */
    manage() {
      return new Options(this)
    }
  
    /** @override */
    navigate() {
      return new Navigation(this)
    }
  
    /** @override */
    switchTo() {
      return new TargetLocator(this)
    }
  
    validatePrintPageParams(keys, object) {
      let page = {}
      let margin = {}
      let data
      Object.keys(keys).forEach(function (key) {
        data = keys[key]
        let obj = {
          orientation: function () {
            object.orientation = data
          },
  
          scale: function () {
            object.scale = data
          },
  
          background: function () {
            object.background = data
          },
  
          width: function () {
            page.width = data
            object.page = page
          },
  
          height: function () {
            page.height = data
            object.page = page
          },
  
          top: function () {
            margin.top = data
            object.margin = margin
          },
  
          left: function () {
            margin.left = data
            object.margin = margin
          },
  
          bottom: function () {
            margin.bottom = data
            object.margin = margin
          },
  
          right: function () {
            margin.right = data
            object.margin = margin
          },
  
          shrinkToFit: function () {
            object.shrinkToFit = data
          },
  
          pageRanges: function () {
            object.pageRanges = data
          },
        }
  
        if (!Object.prototype.hasOwnProperty.call(obj, key)) {
          throw new error.InvalidArgumentError(`Invalid Argument '${key}'`)
        } else {
          obj[key]()
        }
      })
  
      return object
    }
  
    /** @override */
    printPage(options = {}) {
      let keys = options
      let params = {}
      let resultObj
  
      let self = this
      resultObj = self.validatePrintPageParams(keys, params)
  
      return this.execute(
        new command.Command(command.Name.PRINT_PAGE).setParameters(resultObj)
      )
    }
  
    /**
     * Creates a new WebSocket connection.
     * @return {!Promise<resolved>} A new CDP instance.
     */
    async createCDPConnection(target) {
      const caps = await this.getCapabilities()
      const seCdp = caps['map_'].get('se:cdp')
      const vendorInfo =
        caps['map_'].get(this.VENDOR_COMMAND_PREFIX + ':chromeOptions') ||
        caps['map_'].get(this.VENDOR_CAPABILITY_PREFIX + ':edgeOptions') ||
        caps['map_'].get('moz:debuggerAddress') ||
        new Map()
      const debuggerUrl = seCdp || vendorInfo['debuggerAddress'] || vendorInfo
      this._wsUrl = await this.getWsUrl(debuggerUrl, target, caps)
      return new Promise((resolve, reject) => {
        try {
          this._wsConnection = new WebSocket(this._wsUrl)
          this._cdpConnection = new cdp.CdpConnection(this._wsConnection)
        } catch (err) {
          reject(err)
          return
        }
  
        this._wsConnection.on('open', async () => {
          await this.getCdpTargets()
        })
  
        this._wsConnection.on('message', async (message) => {
          const params = JSON.parse(message)
          if (params.result) {
            if (params.result.targetInfos) {
              const targets = params.result.targetInfos
              const page = targets.find((info) => info.type === 'page')
              if (page) {
                this.targetID = page.targetId
                this._cdpConnection.execute(
                  'Target.attachToTarget',
                  { targetId: this.targetID, flatten: true },
                  null
                )
              } else {
                reject('Unable to find Page target.')
              }
            }
            if (params.result.sessionId) {
              this.sessionId = params.result.sessionId
              this._cdpConnection.sessionId = this.sessionId
              resolve(this._cdpConnection)
            }
          }
        })
  
        this._wsConnection.on('error', (error) => {
          reject(error)
        })
      })
    }
  
    async getCdpTargets() {
      this._cdpConnection.execute('Target.getTargets')
    }
  
    /**
     * Retrieves 'webSocketDebuggerUrl' by sending a http request using debugger address
     * @param {string} debuggerAddress
     * @param target
     * @param caps
     * @return {string} Returns parsed webSocketDebuggerUrl obtained from the http request
     */
    async getWsUrl(debuggerAddress, target, caps) {
      if (target && cdpTargets.indexOf(target.toLowerCase()) === -1) {
        throw new error.InvalidArgumentError('invalid target value')
      }
  
      if (debuggerAddress.match(/\/se\/cdp/)) {
        return debuggerAddress
      }
  
      let path
      if (target === 'page' && caps['map_'].get('browserName') !== 'firefox') {
        path = '/json'
      } else if (
        target === 'page' &&
        caps['map_'].get('browserName') === 'firefox'
      ) {
        path = '/json/list'
      } else {
        path = '/json/version'
      }
  
      let request = new http.Request('GET', path)
      let client = new http.HttpClient('http://' + debuggerAddress)
      let response = await client.send(request)
  
      if (target.toLowerCase() === 'page') {
        return JSON.parse(response.body)[0]['webSocketDebuggerUrl']
      } else {
        return JSON.parse(response.body)['webSocketDebuggerUrl']
      }
    }
  
    /**
     * Sets a listener for Fetch.authRequired event from CDP
     * If event is triggered, it enter username and password
     * and allows the test to move forward
     * @param {string} username
     * @param {string} password
     * @param connection CDP Connection
     */
    async register(username, password, connection) {
      this._wsConnection.on('message', (message) => {
        const params = JSON.parse(message)
  
        if (params.method === 'Fetch.authRequired') {
          const requestParams = params['params']
          connection.execute('Fetch.continueWithAuth', {
            requestId: requestParams['requestId'],
            authChallengeResponse: {
              response: 'ProvideCredentials',
              username: username,
              password: password,
            },
          })
        } else if (params.method === 'Fetch.requestPaused') {
          const requestPausedParams = params['params']
          connection.execute('Fetch.continueRequest', {
            requestId: requestPausedParams['requestId'],
          })
        }
      })
  
      await connection.execute(
        'Fetch.enable',
        {
          handleAuthRequests: true,
        },
        null
      )
      await connection.execute(
        'Network.setCacheDisabled',
        {
          cacheDisabled: true,
        },
        null
      )
    }
  
    /**
     * Handle Network interception requests
     * @param connection WebSocket connection to the browser
     * @param httpResponse Object representing what we are intercepting
     *                     as well as what should be returned.
     * @param callback callback called when we intercept requests.
     */
    async onIntercept(connection, httpResponse, callback) {
      this._wsConnection.on('message', (message) => {
        const params = JSON.parse(message)
        if (params.method === 'Fetch.requestPaused') {
          const requestPausedParams = params['params']
          if (requestPausedParams.request.url == httpResponse.urlToIntercept) {
            connection.execute('Fetch.continueRequest', {
              requestId: requestPausedParams['requestId'],
              url: httpResponse.urlToIntercept,
              method: httpResponse.method,
              headers: httpResponse.headers,
              postData: httpResponse.body,
            })
            callback()
          } else {
            connection.execute('Fetch.continueRequest', {
              requestId: requestPausedParams['requestId'],
            })
          }
        }
      })
  
      await connection.execute('Fetch.enable', {}, null)
      await connection.execute(
        'Network.setCacheDisabled',
        {
          cacheDisabled: true,
        },
        null
      )
    }
    /**
     *
     * @param connection
     * @param callback
     * @returns {Promise<void>}
     */
    async onLogEvent(connection, callback) {
      this._wsConnection.on('message', (message) => {
        const params = JSON.parse(message)
        if (params.method === 'Runtime.consoleAPICalled') {
          const consoleEventParams = params['params']
          let event = {
            type: consoleEventParams['type'],
            timestamp: new Date(consoleEventParams['timestamp']),
            args: consoleEventParams['args'],
          }
  
          callback(event)
        }
      })
      await connection.execute('Runtime.enable', {}, null)
    }
  
    /**
     *
     * @param connection
     * @param callback
     * @returns {Promise<void>}
     */
    async onLogException(connection, callback) {
      await connection.execute('Runtime.enable', {}, null)
  
      this._wsConnection.on('message', (message) => {
        const params = JSON.parse(message)
  
        if (params.method === 'Runtime.exceptionThrown') {
          const exceptionEventParams = params['params']
          let event = {
            exceptionDetails: exceptionEventParams['exceptionDetails'],
            timestamp: new Date(exceptionEventParams['timestamp']),
          }
  
          callback(event)
        }
      })
    }
  
    /**
     * @param connection
     * @param callback
     * @returns {Promise<void>}
     */
    async logMutationEvents(connection, callback) {
      await connection.execute('Runtime.enable', {}, null)
      await connection.execute('Page.enable', {}, null)
  
      await connection.execute(
        'Runtime.addBinding',
        {
          name: '__webdriver_attribute',
        },
        null
      )
  
      let mutationListener = ''
      try {
        // Depending on what is running the code it could appear in 2 different places which is why we try
        // here and then the other location
        mutationListener = fs
          .readFileSync(
            './javascript/node/selenium-webdriver/lib/atoms/mutation-listener.js',
            'utf-8'
          )
          .toString()
      } catch {
        mutationListener = fs
          .readFileSync(
            path.resolve(__dirname, './atoms/mutation-listener.js'),
            'utf-8'
          )
          .toString()
      }
  
      this.executeScript(mutationListener)
  
      await connection.execute(
        'Page.addScriptToEvaluateOnNewDocument',
        {
          source: mutationListener,
        },
        null
      )
  
      this._wsConnection.on('message', async (message) => {
        const params = JSON.parse(message)
        if (params.method === 'Runtime.bindingCalled') {
          let payload = JSON.parse(params['params']['payload'])
          let elements = await this.findElements({
            css: '*[data-__webdriver_id=' + payload['target'],
          })
  
          if (elements.length === 0) {
            return
          }
  
          let event = {
            element: elements[0],
            attribute_name: payload['name'],
            current_value: payload['value'],
            old_value: payload['oldValue'],
          }
          callback(event)
        }
      })
    }
  }
  
  /**
   * Interface for navigating back and forth in the browser history.
   *
   * This class should never be instantiated directly. Instead, obtain an instance
   * with
   *
   *    webdriver.navigate()
   *
   * @see WebDriver#navigate()
   */
  class Navigation {
    /**
     * @param {!WebDriver} driver The parent driver.
     * @private
     */
    constructor(driver) {
      /** @private {!WebDriver} */
      this.driver_ = driver
    }
  
    /**
     * Navigates to a new URL.
     *
     * @param {string} url The URL to navigate to.
     * @return {!Promise<void>} A promise that will be resolved when the URL
     *     has been loaded.
     */
    to(url) {
      return this.driver_.execute(
        new command.Command(command.Name.GET).setParameter('url', url)
      )
    }
  
    /**
     * Moves backwards in the browser history.
     *
     * @return {!Promise<void>} A promise that will be resolved when the
     *     navigation event has completed.
     */
    back() {
      return this.driver_.execute(new command.Command(command.Name.GO_BACK))
    }
  
    /**
     * Moves forwards in the browser history.
     *
     * @return {!Promise<void>} A promise that will be resolved when the
     *     navigation event has completed.
     */
    forward() {
      return this.driver_.execute(new command.Command(command.Name.GO_FORWARD))
    }
  
    /**
     * Refreshes the current page.
     *
     * @return {!Promise<void>} A promise that will be resolved when the
     *     navigation event has completed.
     */
    refresh() {
      return this.driver_.execute(new command.Command(command.Name.REFRESH))
    }
  }
  
  /**
   * Provides methods for managing browser and driver state.
   *
   * This class should never be instantiated directly. Instead, obtain an instance
   * with {@linkplain WebDriver#manage() webdriver.manage()}.
   */
  class Options {
    /**
     * @param {!WebDriver} driver The parent driver.
     * @private
     */
    constructor(driver) {
      /** @private {!WebDriver} */
      this.driver_ = driver
    }
  
    /**
     * Adds a cookie.
     *
     * __Sample Usage:__
     *
     *     // Set a basic cookie.
     *     driver.manage().addCookie({name: 'foo', value: 'bar'});
     *
     *     // Set a cookie that expires in 10 minutes.
     *     let expiry = new Date(Date.now() + (10 * 60 * 1000));
     *     driver.manage().addCookie({name: 'foo', value: 'bar', expiry});
     *
     *     // The cookie expiration may also be specified in seconds since epoch.
     *     driver.manage().addCookie({
     *       name: 'foo',
     *       value: 'bar',
     *       expiry: Math.floor(Date.now() / 1000)
     *     });
     *
     * @param {!Options.Cookie} spec Defines the cookie to add.
     * @return {!Promise<void>} A promise that will be resolved
     *     when the cookie has been added to the page.
     * @throws {error.InvalidArgumentError} if any of the cookie parameters are
     *     invalid.
     * @throws {TypeError} if `spec` is not a cookie object.
     */
    addCookie({ name, value, path, domain, secure, httpOnly, expiry, sameSite }) {
      // We do not allow '=' or ';' in the name.
      if (/[;=]/.test(name)) {
        throw new error.InvalidArgumentError('Invalid cookie name "' + name + '"')
      }
  
      // We do not allow ';' in value.
      if (/;/.test(value)) {
        throw new error.InvalidArgumentError(
          'Invalid cookie value "' + value + '"'
        )
      }
  
      if (typeof expiry === 'number') {
        expiry = Math.floor(expiry)
      } else if (expiry instanceof Date) {
        let date = /** @type {!Date} */ (expiry)
        expiry = Math.floor(date.getTime() / 1000)
      }
  
      if (sameSite && !['Strict', 'Lax', 'None'].includes(sameSite)) {
        throw new error.InvalidArgumentError(
          `Invalid sameSite cookie value '${sameSite}'. It should be one of "Lax", "Strict" or "None"`
        )
      }
  
      if (sameSite === 'None' && !secure) {
        throw new error.InvalidArgumentError(
          'Invalid cookie configuration: SameSite=None must be Secure'
        )
      }
  
      return this.driver_.execute(
        new command.Command(command.Name.ADD_COOKIE).setParameter('cookie', {
          name: name,
          value: value,
          path: path,
          domain: domain,
          secure: !!secure,
          httpOnly: !!httpOnly,
          expiry: expiry,
          sameSite: sameSite,
        })
      )
    }
  
    /**
     * Deletes all cookies visible to the current page.
     *
     * @return {!Promise<void>} A promise that will be resolved
     *     when all cookies have been deleted.
     */
    deleteAllCookies() {
      return this.driver_.execute(
        new command.Command(command.Name.DELETE_ALL_COOKIES)
      )
    }
  
    /**
     * Deletes the cookie with the given name. This command is a no-op if there is
     * no cookie with the given name visible to the current page.
     *
     * @param {string} name The name of the cookie to delete.
     * @return {!Promise<void>} A promise that will be resolved
     *     when the cookie has been deleted.
     */
    deleteCookie(name) {
      return this.driver_.execute(
        new command.Command(command.Name.DELETE_COOKIE).setParameter('name', name)
      )
    }
  
    /**
     * Retrieves all cookies visible to the current page. Each cookie will be
     * returned as a JSON object as described by the WebDriver wire protocol.
     *
     * @return {!Promise<!Array<!Options.Cookie>>} A promise that will be
     *     resolved with the cookies visible to the current browsing context.
     */
    getCookies() {
      return this.driver_.execute(
        new command.Command(command.Name.GET_ALL_COOKIES)
      )
    }
  
    /**
     * Retrieves the cookie with the given name. Returns null if there is no such
     * cookie. The cookie will be returned as a JSON object as described by the
     * WebDriver wire protocol.
     *
     * @param {string} name The name of the cookie to retrieve.
     * @return {!Promise<?Options.Cookie>} A promise that will be resolved
     *     with the named cookie
     * @throws {error.NoSuchCookieError} if there is no such cookie.
     */
    async getCookie(name) {
      try {
        const cookie = await this.driver_.execute(
          new command.Command(command.Name.GET_COOKIE).setParameter('name', name)
        )
        return cookie
      } catch (err) {
        if (
          !(err instanceof error.UnknownCommandError) &&
          !(err instanceof error.UnsupportedOperationError)
        ) {
          throw err
        }
  
        const cookies = await this.getCookies()
        for (let cookie of cookies) {
          if (cookie && cookie['name'] === name) {
            return cookie
          }
        }
        return null
      }
    }
  
    /**
     * Fetches the timeouts currently configured for the current session.
     *
     * @return {!Promise<{script: number,
     *                             pageLoad: number,
     *                             implicit: number}>} A promise that will be
     *     resolved with the timeouts currently configured for the current
     *     session.
     * @see #setTimeouts()
     */
    getTimeouts() {
      return this.driver_.execute(new command.Command(command.Name.GET_TIMEOUT))
    }
  
    /**
     * Sets the timeout durations associated with the current session.
     *
     * The following timeouts are supported (all timeouts are specified in
     * milliseconds):
     *
     * -  `implicit` specifies the maximum amount of time to wait for an element
     *    locator to succeed when {@linkplain WebDriver#findElement locating}
     *    {@linkplain WebDriver#findElements elements} on the page.
     *    Defaults to 0 milliseconds.
     *
     * -  `pageLoad` specifies the maximum amount of time to wait for a page to
     *    finishing loading. Defaults to 300000 milliseconds.
     *
     * -  `script` specifies the maximum amount of time to wait for an
     *    {@linkplain WebDriver#executeScript evaluated script} to run. If set to
     *    `null`, the script timeout will be indefinite.
     *    Defaults to 30000 milliseconds.
     *
     * @param {{script: (number|null|undefined),
     *          pageLoad: (number|null|undefined),
     *          implicit: (number|null|undefined)}} conf
     *     The desired timeout configuration.
     * @return {!Promise<void>} A promise that will be resolved when the timeouts
     *     have been set.
     * @throws {!TypeError} if an invalid options object is provided.
     * @see #getTimeouts()
     * @see <https://w3c.github.io/webdriver/webdriver-spec.html#dfn-set-timeouts>
     */
    setTimeouts({ script, pageLoad, implicit } = {}) {
      let cmd = new command.Command(command.Name.SET_TIMEOUT)
  
      let valid = false
      function setParam(key, value) {
        if (value === null || typeof value === 'number') {
          valid = true
          cmd.setParameter(key, value)
        } else if (typeof value !== 'undefined') {
          throw TypeError(
            'invalid timeouts configuration:' +
              ` expected "${key}" to be a number, got ${typeof value}`
          )
        }
      }
      setParam('implicit', implicit)
      setParam('pageLoad', pageLoad)
      setParam('script', script)
  
      if (valid) {
        return this.driver_.execute(cmd).catch(() => {
          // Fallback to the legacy method.
          let cmds = []
          if (typeof script === 'number') {
            cmds.push(legacyTimeout(this.driver_, 'script', script))
          }
          if (typeof implicit === 'number') {
            cmds.push(legacyTimeout(this.driver_, 'implicit', implicit))
          }
          if (typeof pageLoad === 'number') {
            cmds.push(legacyTimeout(this.driver_, 'page load', pageLoad))
          }
          return Promise.all(cmds)
        })
      }
      throw TypeError('no timeouts specified')
    }
  
    /**
     * @return {!Logs} The interface for managing driver logs.
     */
    logs() {
      return new Logs(this.driver_)
    }
  
    /**
     * @return {!Window} The interface for managing the current window.
     */
    window() {
      return new Window(this.driver_)
    }
  }
  
  /**
   * @param {!WebDriver} driver
   * @param {string} type
   * @param {number} ms
   * @return {!Promise<void>}
   */
  function legacyTimeout(driver, type, ms) {
    return driver.execute(
      new command.Command(command.Name.SET_TIMEOUT)
        .setParameter('type', type)
        .setParameter('ms', ms)
    )
  }
  
  /**
   * A record object describing a browser cookie.
   *
   * @record
   */
  Options.Cookie = function () {}
  
  /**
   * The name of the cookie.
   *
   * @type {string}
   */
  Options.Cookie.prototype.name
  
  /**
   * The cookie value.
   *
   * @type {string}
   */
  Options.Cookie.prototype.value
  
  /**
   * The cookie path. Defaults to "/" when adding a cookie.
   *
   * @type {(string|undefined)}
   */
  Options.Cookie.prototype.path
  
  /**
   * The domain the cookie is visible to. Defaults to the current browsing
   * context's document's URL when adding a cookie.
   *
   * @type {(string|undefined)}
   */
  Options.Cookie.prototype.domain
  
  /**
   * Whether the cookie is a secure cookie. Defaults to false when adding a new
   * cookie.
   *
   * @type {(boolean|undefined)}
   */
  Options.Cookie.prototype.secure
  
  /**
   * Whether the cookie is an HTTP only cookie. Defaults to false when adding a
   * new cookie.
   *
   * @type {(boolean|undefined)}
   */
  Options.Cookie.prototype.httpOnly
  
  /**
   * When the cookie expires.
   *
   * When {@linkplain Options#addCookie() adding a cookie}, this may be specified
   * as a {@link Date} object, or in _seconds_ since Unix epoch (January 1, 1970).
   *
   * The expiry is always returned in seconds since epoch when
   * {@linkplain Options#getCookies() retrieving cookies} from the browser.
   *
   * @type {(!Date|number|undefined)}
   */
  Options.Cookie.prototype.expiry
  
  /**
   * When the cookie applies to a SameSite policy.
   *
   * When {@linkplain Options#addCookie() adding a cookie}, this may be specified
   * as a {@link string} object which is one of 'Lax', 'Strict' or 'None'.
   *
   *
   * @type {(string|undefined)}
   */
  Options.Cookie.prototype.sameSite
  
  /**
   * An interface for managing the current window.
   *
   * This class should never be instantiated directly. Instead, obtain an instance
   * with
   *
   *    webdriver.manage().window()
   *
   * @see WebDriver#manage()
   * @see Options#window()
   */
  class Window {
    /**
     * @param {!WebDriver} driver The parent driver.
     * @private
     */
    constructor(driver) {
      /** @private {!WebDriver} */
      this.driver_ = driver
    }
  
    /**
     * Retrieves the a rect describing the current top-level window's size and
     * position.
     *
     * @return {!Promise<{x: number, y: number, width: number, height: number}>}
     *     A promise that will resolve to the window rect of the current window.
     */
    async getRect() {
      try {
        return await this.driver_.execute(
          new command.Command(command.Name.GET_WINDOW_RECT)
        )
      } catch (ex) {
        if (ex instanceof error.UnknownCommandError) {
          let { width, height } = await this.driver_.execute(
            new command.Command(command.Name.GET_WINDOW_SIZE).setParameter(
              'windowHandle',
              'current'
            )
          )
          let { x, y } = await this.driver_.execute(
            new command.Command(command.Name.GET_WINDOW_POSITION).setParameter(
              'windowHandle',
              'current'
            )
          )
          return { x, y, width, height }
        }
        throw ex
      }
    }
  
    /**
     * Sets the current top-level window's size and position. You may update just
     * the size by omitting `x` & `y`, or just the position by omitting
     * `width` & `height` options.
     *
     * @param {{x: (number|undefined),
     *          y: (number|undefined),
     *          width: (number|undefined),
     *          height: (number|undefined)}} options
     *     The desired window size and position.
     * @return {!Promise<{x: number, y: number, width: number, height: number}>}
     *     A promise that will resolve to the current window's updated window
     *     rect.
     */
    async setRect({ x, y, width, height }) {
      try {
        return await this.driver_.execute(
          new command.Command(command.Name.SET_WINDOW_RECT).setParameters({
            x,
            y,
            width,
            height,
          })
        )
      } catch (ex) {
        if (ex instanceof error.UnknownCommandError) {
          if (typeof x === 'number' && typeof y === 'number') {
            await this.driver_.execute(
              new command.Command(command.Name.SET_WINDOW_POSITION)
                .setParameter('windowHandle', 'current')
                .setParameter('x', x)
                .setParameter('y', y)
            )
          }
  
          if (typeof width === 'number' && typeof height === 'number') {
            await this.driver_.execute(
              new command.Command(command.Name.SET_WINDOW_SIZE)
                .setParameter('windowHandle', 'current')
                .setParameter('width', width)
                .setParameter('height', height)
            )
          }
          return this.getRect()
        }
        throw ex
      }
    }
  
    /**
     * Maximizes the current window. The exact behavior of this command is
     * specific to individual window managers, but typically involves increasing
     * the window to the maximum available size without going full-screen.
     *
     * @return {!Promise<void>} A promise that will be resolved when the command
     *     has completed.
     */
    maximize() {
      return this.driver_.execute(
        new command.Command(command.Name.MAXIMIZE_WINDOW).setParameter(
          'windowHandle',
          'current'
        )
      )
    }
  
    /**
     * Minimizes the current window. The exact behavior of this command is
     * specific to individual window managers, but typically involves hiding
     * the window in the system tray.
     *
     * @return {!Promise<void>} A promise that will be resolved when the command
     *     has completed.
     */
    minimize() {
      return this.driver_.execute(
        new command.Command(command.Name.MINIMIZE_WINDOW)
      )
    }
  
    /**
     * Invokes the "full screen" operation on the current window. The exact
     * behavior of this command is specific to individual window managers, but
     * this will typically increase the window size to the size of the physical
     * display and hide the browser chrome.
     *
     * @return {!Promise<void>} A promise that will be resolved when the command
     *     has completed.
     * @see <https://fullscreen.spec.whatwg.org/#fullscreen-an-element>
     */
    fullscreen() {
      return this.driver_.execute(
        new command.Command(command.Name.FULLSCREEN_WINDOW)
      )
    }
  }
  
  /**
   * Interface for managing WebDriver log records.
   *
   * This class should never be instantiated directly. Instead, obtain an
   * instance with
   *
   *     webdriver.manage().logs()
   *
   * @see WebDriver#manage()
   * @see Options#logs()
   */
  class Logs {
    /**
     * @param {!WebDriver} driver The parent driver.
     * @private
     */
    constructor(driver) {
      /** @private {!WebDriver} */
      this.driver_ = driver
    }
  
    /**
     * Fetches available log entries for the given type.
     *
     * Note that log buffers are reset after each call, meaning that available
     * log entries correspond to those entries not yet returned for a given log
     * type. In practice, this means that this call will return the available log
     * entries since the last call, or from the start of the session.
     *
     * @param {!logging.Type} type The desired log type.
     * @return {!Promise<!Array.<!logging.Entry>>} A
     *   promise that will resolve to a list of log entries for the specified
     *   type.
     */
    get(type) {
      let cmd = new command.Command(command.Name.GET_LOG).setParameter(
        'type',
        type
      )
      return this.driver_.execute(cmd).then(function (entries) {
        return entries.map(function (entry) {
          if (!(entry instanceof logging.Entry)) {
            return new logging.Entry(
              entry['level'],
              entry['message'],
              entry['timestamp'],
              entry['type']
            )
          }
          return entry
        })
      })
    }
  
    /**
     * Retrieves the log types available to this driver.
     * @return {!Promise<!Array<!logging.Type>>} A
     *     promise that will resolve to a list of available log types.
     */
    getAvailableLogTypes() {
      return this.driver_.execute(
        new command.Command(command.Name.GET_AVAILABLE_LOG_TYPES)
      )
    }
  }
  
  /**
   * An interface for changing the focus of the driver to another frame or window.
   *
   * This class should never be instantiated directly. Instead, obtain an
   * instance with
   *
   *     webdriver.switchTo()
   *
   * @see WebDriver#switchTo()
   */
  class TargetLocator {
    /**
     * @param {!WebDriver} driver The parent driver.
     * @private
     */
    constructor(driver) {
      /** @private {!WebDriver} */
      this.driver_ = driver
    }
  
    /**
     * Locates the DOM element on the current page that corresponds to
     * `document.activeElement` or `document.body` if the active element is not
     * available.
     *
     * @return {!WebElementPromise} The active element.
     */
    activeElement() {
      const id = this.driver_.execute(
        new command.Command(command.Name.GET_ACTIVE_ELEMENT)
      )
      return new WebElementPromise(this.driver_, id)
    }
  
    /**
     * Switches focus of all future commands to the topmost frame in the current
     * window.
     *
     * @return {!Promise<void>} A promise that will be resolved
     *     when the driver has changed focus to the default content.
     */
    defaultContent() {
      return this.driver_.execute(
        new command.Command(command.Name.SWITCH_TO_FRAME).setParameter('id', null)
      )
    }
  
    /**
     * Changes the focus of all future commands to another frame on the page. The
     * target frame may be specified as one of the following:
     *
     * - A number that specifies a (zero-based) index into [window.frames](
     *   https://developer.mozilla.org/en-US/docs/Web/API/Window.frames).
     * - A {@link WebElement} reference, which correspond to a `frame` or `iframe`
     *   DOM element.
     * - The `null` value, to select the topmost frame on the page. Passing `null`
     *   is the same as calling {@link #defaultContent defaultContent()}.
     *
     * If the specified frame can not be found, the returned promise will be
     * rejected with a {@linkplain error.NoSuchFrameError}.
     *
     * @param {(number|WebElement|null)} id The frame locator.
     * @return {!Promise<void>} A promise that will be resolved
     *     when the driver has changed focus to the specified frame.
     */
    frame(id) {
      return this.driver_.execute(
        new command.Command(command.Name.SWITCH_TO_FRAME).setParameter('id', id)
      )
    }
  
    /**
     * Changes the focus of all future commands to the parent frame of the
     * currently selected frame. This command has no effect if the driver is
     * already focused on the top-level browsing context.
     *
     * @return {!Promise<void>} A promise that will be resolved when the command
     *     has completed.
     */
    parentFrame() {
      return this.driver_.execute(
        new command.Command(command.Name.SWITCH_TO_FRAME_PARENT)
      )
    }
  
    /**
     * Changes the focus of all future commands to another window. Windows may be
     * specified by their {@code window.name} attribute or by its handle
     * (as returned by {@link WebDriver#getWindowHandles}).
     *
     * If the specified window cannot be found, the returned promise will be
     * rejected with a {@linkplain error.NoSuchWindowError}.
     *
     * @param {string} nameOrHandle The name or window handle of the window to
     *     switch focus to.
     * @return {!Promise<void>} A promise that will be resolved
     *     when the driver has changed focus to the specified window.
     */
    window(nameOrHandle) {
      return this.driver_.execute(
        new command.Command(command.Name.SWITCH_TO_WINDOW)
          // "name" supports the legacy drivers. "handle" is the W3C
          // compliant parameter.
          .setParameter('name', nameOrHandle)
          .setParameter('handle', nameOrHandle)
      )
    }
  
    /**
     * Creates a new browser window and switches the focus for future
     * commands of this driver to the new window.
     *
     * @param {string} typeHint 'window' or 'tab'. The created window is not
     *     guaranteed to be of the requested type; if the driver does not support
     *     the requested type, a new browser window will be created of whatever type
     *     the driver does support.
     * @return {!Promise<void>} A promise that will be resolved
     *     when the driver has changed focus to the new window.
     */
    newWindow(typeHint) {
      const driver = this.driver_
      return this.driver_
        .execute(
          new command.Command(command.Name.SWITCH_TO_NEW_WINDOW).setParameter(
            'type',
            typeHint
          )
        )
        .then(function (response) {
          return driver.switchTo().window(response.handle)
        })
    }
  
    /**
     * Changes focus to the active modal dialog, such as those opened by
     * `window.alert()`, `window.confirm()`, and `window.prompt()`. The returned
     * promise will be rejected with a
     * {@linkplain error.NoSuchAlertError} if there are no open alerts.
     *
     * @return {!AlertPromise} The open alert.
     */
    alert() {
      const text = this.driver_.execute(
        new command.Command(command.Name.GET_ALERT_TEXT)
      )
      const driver = this.driver_
      return new AlertPromise(
        driver,
        text.then(function (text) {
          return new Alert(driver, text)
        })
      )
    }
  }
  
  //////////////////////////////////////////////////////////////////////////////
  //
  //  WebElement
  //
  //////////////////////////////////////////////////////////////////////////////
  
  const LEGACY_ELEMENT_ID_KEY = 'ELEMENT'
  const ELEMENT_ID_KEY = 'element-6066-11e4-a52e-4f735466cecf'
  
  /**
   * Represents a DOM element. WebElements can be found by searching from the
   * document root using a {@link WebDriver} instance, or by searching
   * under another WebElement:
   *
   *     driver.get('http://www.google.com');
   *     var searchForm = driver.findElement(By.tagName('form'));
   *     var searchBox = searchForm.findElement(By.name('q'));
   *     searchBox.sendKeys('webdriver');
   */
  class WebElement {
    /**
     * @param {!WebDriver} driver the parent WebDriver instance for this element.
     * @param {(!IThenable<string>|string)} id The server-assigned opaque ID for
     *     the underlying DOM element.
     */
    constructor(driver, id) {
      /** @private {!WebDriver} */
      this.driver_ = driver
  
      /** @private {!Promise<string>} */
      this.id_ = Promise.resolve(id)
    }
  
    /**
     * @param {string} id The raw ID.
     * @param {boolean=} noLegacy Whether to exclude the legacy element key.
     * @return {!Object} The element ID for use with WebDriver's wire protocol.
     */
    static buildId(id, noLegacy = false) {
      return noLegacy
        ? { [ELEMENT_ID_KEY]: id }
        : { [ELEMENT_ID_KEY]: id, [LEGACY_ELEMENT_ID_KEY]: id }
    }
  
    /**
     * Extracts the encoded WebElement ID from the object.
     *
     * @param {?} obj The object to extract the ID from.
     * @return {string} the extracted ID.
     * @throws {TypeError} if the object is not a valid encoded ID.
     */
    static extractId(obj) {
      if (obj && typeof obj === 'object') {
        if (typeof obj[ELEMENT_ID_KEY] === 'string') {
          return obj[ELEMENT_ID_KEY]
        } else if (typeof obj[LEGACY_ELEMENT_ID_KEY] === 'string') {
          return obj[LEGACY_ELEMENT_ID_KEY]
        }
      }
      throw new TypeError('object is not a WebElement ID')
    }
  
    /**
     * @param {?} obj the object to test.
     * @return {boolean} whether the object is a valid encoded WebElement ID.
     */
    static isId(obj) {
      return (
        obj &&
        typeof obj === 'object' &&
        (typeof obj[ELEMENT_ID_KEY] === 'string' ||
          typeof obj[LEGACY_ELEMENT_ID_KEY] === 'string')
      )
    }
  
    /**
     * Compares two WebElements for equality.
     *
     * @param {!WebElement} a A WebElement.
     * @param {!WebElement} b A WebElement.
     * @return {!Promise<boolean>} A promise that will be
     *     resolved to whether the two WebElements are equal.
     */
    static async equals(a, b) {
      if (a === b) {
        return true
      }
      return a.driver_.executeScript('return arguments[0] === arguments[1]', a, b)
    }
  
    /** @return {!WebDriver} The parent driver for this instance. */
    getDriver() {
      return this.driver_
    }
  
    /**
     * @return {!Promise<string>} A promise that resolves to
     *     the server-assigned opaque ID assigned to this element.
     */
    getId() {
      return this.id_
    }
  
    /**
     * @return {!Object} Returns the serialized representation of this WebElement.
     */
    [Symbols.serialize]() {
      return this.getId().then(WebElement.buildId)
    }
  
    /**
     * Schedules a command that targets this element with the parent WebDriver
     * instance. Will ensure this element's ID is included in the command
     * parameters under the "id" key.
     *
     * @param {!command.Command} command The command to schedule.
     * @return {!Promise<T>} A promise that will be resolved with the result.
     * @template T
     * @see WebDriver#schedule
     * @private
     */
    execute_(command) {
      command.setParameter('id', this)
      return this.driver_.execute(command)
    }
  
    /**
     * Schedule a command to find a descendant of this element. If the element
     * cannot be found, the returned promise will be rejected with a
     * {@linkplain error.NoSuchElementError NoSuchElementError}.
     *
     * The search criteria for an element may be defined using one of the static
     * factories on the {@link by.By} class, or as a short-hand
     * {@link ./by.ByHash} object. For example, the following two statements
     * are equivalent:
     *
     *     var e1 = element.findElement(By.id('foo'));
     *     var e2 = element.findElement({id:'foo'});
     *
     * You may also provide a custom locator function, which takes as input this
     * instance and returns a {@link WebElement}, or a promise that will resolve
     * to a WebElement. If the returned promise resolves to an array of
     * WebElements, WebDriver will use the first element. For example, to find the
     * first visible link on a page, you could write:
     *
     *     var link = element.findElement(firstVisibleLink);
     *
     *     function firstVisibleLink(element) {
     *       var links = element.findElements(By.tagName('a'));
     *       return promise.filter(links, function(link) {
     *         return link.isDisplayed();
     *       });
     *     }
     *
     * @param {!(by.By|Function)} locator The locator strategy to use when
     *     searching for the element.
     * @return {!WebElementPromise} A WebElement that can be used to issue
     *     commands against the located element. If the element is not found, the
     *     element will be invalidated and all scheduled commands aborted.
     */
    findElement(locator) {
      locator = by.checkedLocator(locator)
      let id
      if (typeof locator === 'function') {
        id = this.driver_.findElementInternal_(locator, this)
      } else {
        let cmd = new command.Command(command.Name.FIND_CHILD_ELEMENT)
          .setParameter('using', locator.using)
          .setParameter('value', locator.value)
        id = this.execute_(cmd)
      }
      return new WebElementPromise(this.driver_, id)
    }
  
    /**
     * Locates all of the descendants of this element that match the given search
     * criteria.
     *
     * @param {!(by.By|Function)} locator The locator strategy to use when
     *     searching for the element.
     * @return {!Promise<!Array<!WebElement>>} A promise that will resolve to an
     *     array of WebElements.
     */
    async findElements(locator) {
      locator = by.checkedLocator(locator)
      if (typeof locator === 'function') {
        return this.driver_.findElementsInternal_(locator, this)
      } else {
        let cmd = new command.Command(command.Name.FIND_CHILD_ELEMENTS)
          .setParameter('using', locator.using)
          .setParameter('value', locator.value)
        let result = await this.execute_(cmd)
        return Array.isArray(result) ? result : []
      }
    }
  
    /**
     * Clicks on this element.
     *
     * @return {!Promise<void>} A promise that will be resolved when the click
     *     command has completed.
     */
    click() {
      return this.execute_(new command.Command(command.Name.CLICK_ELEMENT))
    }
  
    /**
     * Types a key sequence on the DOM element represented by this instance.
     *
     * Modifier keys (SHIFT, CONTROL, ALT, META) are stateful; once a modifier is
     * processed in the key sequence, that key state is toggled until one of the
     * following occurs:
     *
     * - The modifier key is encountered again in the sequence. At this point the
     *   state of the key is toggled (along with the appropriate keyup/down
     *   events).
     * - The {@link input.Key.NULL} key is encountered in the sequence. When
     *   this key is encountered, all modifier keys current in the down state are
     *   released (with accompanying keyup events). The NULL key can be used to
     *   simulate common keyboard shortcuts:
     *
     *         element.sendKeys("text was",
     *                          Key.CONTROL, "a", Key.NULL,
     *                          "now text is");
     *         // Alternatively:
     *         element.sendKeys("text was",
     *                          Key.chord(Key.CONTROL, "a"),
     *                          "now text is");
     *
     * - The end of the key sequence is encountered. When there are no more keys
     *   to type, all depressed modifier keys are released (with accompanying
     *   keyup events).
     *
     * If this element is a file input ({@code <input type="file">}), the
     * specified key sequence should specify the path to the file to attach to
     * the element. This is analogous to the user clicking "Browse..." and entering
     * the path into the file select dialog.
     *
     *     var form = driver.findElement(By.css('form'));
     *     var element = form.findElement(By.css('input[type=file]'));
     *     element.sendKeys('/path/to/file.txt');
     *     form.submit();
     *
     * For uploads to function correctly, the entered path must reference a file
     * on the _browser's_ machine, not the local machine running this script. When
     * running against a remote Selenium server, a {@link input.FileDetector}
     * may be used to transparently copy files to the remote machine before
     * attempting to upload them in the browser.
     *
     * __Note:__ On browsers where native keyboard events are not supported
     * (e.g. Firefox on OS X), key events will be synthesized. Special
     * punctuation keys will be synthesized according to a standard QWERTY en-us
     * keyboard layout.
     *
     * @param {...(number|string|!IThenable<(number|string)>)} args The
     *     sequence of keys to type. Number keys may be referenced numerically or
     *     by string (1 or '1'). All arguments will be joined into a single
     *     sequence.
     * @return {!Promise<void>} A promise that will be resolved when all keys
     *     have been typed.
     */
    async sendKeys(...args) {
      let keys = []
      ;(await Promise.all(args)).forEach((key) => {
        let type = typeof key
        if (type === 'number') {
          key = String(key)
        } else if (type !== 'string') {
          throw TypeError('each key must be a number of string; got ' + type)
        }
  
        // The W3C protocol requires keys to be specified as an array where
        // each element is a single key.
        keys.push(...key.split(''))
      })
  
      if (!this.driver_.fileDetector_) {
        return this.execute_(
          new command.Command(command.Name.SEND_KEYS_TO_ELEMENT)
            .setParameter('text', keys.join(''))
            .setParameter('value', keys)
        )
      }
  
      keys = await this.driver_.fileDetector_.handleFile(
        this.driver_,
        keys.join('')
      )
      return this.execute_(
        new command.Command(command.Name.SEND_KEYS_TO_ELEMENT)
          .setParameter('text', keys)
          .setParameter('value', keys.split(''))
      )
    }
  
    /**
     * Retrieves the element's tag name.
     *
     * @return {!Promise<string>} A promise that will be resolved with the
     *     element's tag name.
     */
    getTagName() {
      return this.execute_(new command.Command(command.Name.GET_ELEMENT_TAG_NAME))
    }
  
    /**
     * Retrieves the value of a computed style property for this instance. If
     * the element inherits the named style from its parent, the parent will be
     * queried for its value.  Where possible, color values will be converted to
     * their hex representation (e.g. #00ff00 instead of rgb(0, 255, 0)).
     *
     * _Warning:_ the value returned will be as the browser interprets it, so
     * it may be tricky to form a proper assertion.
     *
     * @param {string} cssStyleProperty The name of the CSS style property to look
     *     up.
     * @return {!Promise<string>} A promise that will be resolved with the
     *     requested CSS value.
     */
    getCssValue(cssStyleProperty) {
      const name = command.Name.GET_ELEMENT_VALUE_OF_CSS_PROPERTY
      return this.execute_(
        new command.Command(name).setParameter('propertyName', cssStyleProperty)
      )
    }
  
    /**
     * Retrieves the current value of the given attribute of this element.
     * Will return the current value, even if it has been modified after the page
     * has been loaded. More exactly, this method will return the value
     * of the given attribute, unless that attribute is not present, in which case
     * the value of the property with the same name is returned. If neither value
     * is set, null is returned (for example, the "value" property of a textarea
     * element). The "style" attribute is converted as best can be to a
     * text representation with a trailing semi-colon. The following are deemed to
     * be "boolean" attributes and will return either "true" or null:
     *
     * async, autofocus, autoplay, checked, compact, complete, controls, declare,
     * defaultchecked, defaultselected, defer, disabled, draggable, ended,
     * formnovalidate, hidden, indeterminate, iscontenteditable, ismap, itemscope,
     * loop, multiple, muted, nohref, noresize, noshade, novalidate, nowrap, open,
     * paused, pubdate, readonly, required, reversed, scoped, seamless, seeking,
     * selected, spellcheck, truespeed, willvalidate
     *
     * Finally, the following commonly mis-capitalized attribute/property names
     * are evaluated as expected:
     *
     * - "class"
     * - "readonly"
     *
     * @param {string} attributeName The name of the attribute to query.
     * @return {!Promise<?string>} A promise that will be
     *     resolved with the attribute's value. The returned value will always be
     *     either a string or null.
     */
    getAttribute(attributeName) {
      return this.execute_(
        new command.Command(command.Name.GET_ELEMENT_ATTRIBUTE).setParameter(
          'name',
          attributeName
        )
      )
    }
  
    /**
     * Get the given property of the referenced web element
     * @param {string} propertyName The name of the attribute to query.
     * @return {!Promise<string>} A promise that will be
     *     resolved with the element's property value
     */
    getProperty(propertyName) {
      return this.execute_(
        new command.Command(command.Name.GET_ELEMENT_PROPERTY).setParameter(
          'name',
          propertyName
        )
      )
    }
  
    /**
     * Get the visible (i.e. not hidden by CSS) innerText of this element,
     * including sub-elements, without any leading or trailing whitespace.
     *
     * @return {!Promise<string>} A promise that will be
     *     resolved with the element's visible text.
     */
    getText() {
      return this.execute_(new command.Command(command.Name.GET_ELEMENT_TEXT))
    }
  
    /**
     * Get the computed WAI-ARIA role of element.
     *
     * @return {!Promise<string>} A promise that will be
     *     resolved with the element's computed role.
     */
    getAriaRole() {
      return this.execute_(new command.Command(command.Name.GET_COMPUTED_ROLE))
    }
  
    /**
     * Get the computed WAI-ARIA label of element.
     *
     * @return {!Promise<string>} A promise that will be
     *     resolved with the element's computed label.
     */
    getAccessibleName() {
      return this.execute_(new command.Command(command.Name.GET_COMPUTED_LABEL))
    }
    /**
     * Returns an object describing an element's location, in pixels relative to
     * the document element, and the element's size in pixels.
     *
     * @return {!Promise<{width: number, height: number, x: number, y: number}>}
     *     A promise that will resolve with the element's rect.
     */
    async getRect() {
      try {
        return await this.execute_(
          new command.Command(command.Name.GET_ELEMENT_RECT)
        )
      } catch (err) {
        if (err instanceof error.UnknownCommandError) {
          const { width, height } = await this.execute_(
            new command.Command(command.Name.GET_ELEMENT_SIZE)
          )
          const { x, y } = await this.execute_(
            new command.Command(command.Name.GET_ELEMENT_LOCATION)
          )
          return { x, y, width, height }
        }
      }
    }
  
    /**
     * Tests whether this element is enabled, as dictated by the `disabled`
     * attribute.
     *
     * @return {!Promise<boolean>} A promise that will be
     *     resolved with whether this element is currently enabled.
     */
    isEnabled() {
      return this.execute_(new command.Command(command.Name.IS_ELEMENT_ENABLED))
    }
  
    /**
     * Tests whether this element is selected.
     *
     * @return {!Promise<boolean>} A promise that will be
     *     resolved with whether this element is currently selected.
     */
    isSelected() {
      return this.execute_(new command.Command(command.Name.IS_ELEMENT_SELECTED))
    }
  
    /**
     * Submits the form containing this element (or this element if it is itself
     * a FORM element). his command is a no-op if the element is not contained in
     * a form.
     *
     * @return {!Promise<void>} A promise that will be resolved
     *     when the form has been submitted.
     */
    submit() {
      const form = this.findElement({ xpath: './ancestor-or-self::form' })
      this.driver_.executeScript(
        "var e = arguments[0].ownerDocument.createEvent('Event');" +
          "e.initEvent('submit', true, true);" +
          'if (arguments[0].dispatchEvent(e)) { arguments[0].submit() }',
        form
      )
    }
  
    /**
     * Clear the `value` of this element. This command has no effect if the
     * underlying DOM element is neither a text INPUT element nor a TEXTAREA
     * element.
     *
     * @return {!Promise<void>} A promise that will be resolved
     *     when the element has been cleared.
     */
    clear() {
      return this.execute_(new command.Command(command.Name.CLEAR_ELEMENT))
    }
  
    /**
     * Test whether this element is currently displayed.
     *
     * @return {!Promise<boolean>} A promise that will be
     *     resolved with whether this element is currently visible on the page.
     */
    isDisplayed() {
      return this.execute_(new command.Command(command.Name.IS_ELEMENT_DISPLAYED))
    }
  
    /**
     * Take a screenshot of the visible region encompassed by this element's
     * bounding rectangle.
     *
     * @return {!Promise<string>} A promise that will be
     *     resolved to the screenshot as a base-64 encoded PNG.
     */
    takeScreenshot() {
      return this.execute_(
        new command.Command(command.Name.TAKE_ELEMENT_SCREENSHOT)
      )
    }
  }
  
  /**
   * WebElementPromise is a promise that will be fulfilled with a WebElement.
   * This serves as a forward proxy on WebElement, allowing calls to be
   * scheduled without directly on this instance before the underlying
   * WebElement has been fulfilled. In other words, the following two statements
   * are equivalent:
   *
   *     driver.findElement({id: 'my-button'}).click();
   *     driver.findElement({id: 'my-button'}).then(function(el) {
   *       return el.click();
   *     });
   *
   * @implements {IThenable<!WebElement>}
   * @final
   */
  class WebElementPromise extends WebElement {
    /**
     * @param {!WebDriver} driver The parent WebDriver instance for this
     *     element.
     * @param {!Promise<!WebElement>} el A promise
     *     that will resolve to the promised element.
     */
    constructor(driver, el) {
      super(driver, 'unused')
  
      /** @override */
      this.then = el.then.bind(el)
  
      /** @override */
      this.catch = el.catch.bind(el)
  
      /**
       * Defers returning the element ID until the wrapped WebElement has been
       * resolved.
       * @override
       */
      this.getId = function () {
        return el.then(function (el) {
          return el.getId()
        })
      }
    }
  }
  
  //////////////////////////////////////////////////////////////////////////////
  //
  //  Alert
  //
  //////////////////////////////////////////////////////////////////////////////
  
  /**
   * Represents a modal dialog such as {@code alert}, {@code confirm}, or
   * {@code prompt}. Provides functions to retrieve the message displayed with
   * the alert, accept or dismiss the alert, and set the response text (in the
   * case of {@code prompt}).
   */
  class Alert {
    /**
     * @param {!WebDriver} driver The driver controlling the browser this alert
     *     is attached to.
     * @param {string} text The message text displayed with this alert.
     */
    constructor(driver, text) {
      /** @private {!WebDriver} */
      this.driver_ = driver
  
      /** @private {!Promise<string>} */
      this.text_ = Promise.resolve(text)
    }
  
    /**
     * Retrieves the message text displayed with this alert. For instance, if the
     * alert were opened with alert("hello"), then this would return "hello".
     *
     * @return {!Promise<string>} A promise that will be
     *     resolved to the text displayed with this alert.
     */
    getText() {
      return this.text_
    }
  
    /**
     * Accepts this alert.
     *
     * @return {!Promise<void>} A promise that will be resolved
     *     when this command has completed.
     */
    accept() {
      return this.driver_.execute(new command.Command(command.Name.ACCEPT_ALERT))
    }
  
    /**
     * Dismisses this alert.
     *
     * @return {!Promise<void>} A promise that will be resolved
     *     when this command has completed.
     */
    dismiss() {
      return this.driver_.execute(new command.Command(command.Name.DISMISS_ALERT))
    }
  
    /**
     * Sets the response text on this alert. This command will return an error if
     * the underlying alert does not support response text (e.g. window.alert and
     * window.confirm).
     *
     * @param {string} text The text to set.
     * @return {!Promise<void>} A promise that will be resolved
     *     when this command has completed.
     */
    sendKeys(text) {
      return this.driver_.execute(
        new command.Command(command.Name.SET_ALERT_TEXT).setParameter(
          'text',
          text
        )
      )
    }
  }
  
  /**
   * AlertPromise is a promise that will be fulfilled with an Alert. This promise
   * serves as a forward proxy on an Alert, allowing calls to be scheduled
   * directly on this instance before the underlying Alert has been fulfilled. In
   * other words, the following two statements are equivalent:
   *
   *     driver.switchTo().alert().dismiss();
   *     driver.switchTo().alert().then(function(alert) {
   *       return alert.dismiss();
   *     });
   *
   * @implements {IThenable<!Alert>}
   * @final
   */
  class AlertPromise extends Alert {
    /**
     * @param {!WebDriver} driver The driver controlling the browser this
     *     alert is attached to.
     * @param {!Promise<!Alert>} alert A thenable
     *     that will be fulfilled with the promised alert.
     */
    constructor(driver, alert) {
      super(driver, 'unused')
  
      /** @override */
      this.then = alert.then.bind(alert)
  
      /** @override */
      this.catch = alert.catch.bind(alert)
  
      /**
       * Defer returning text until the promised alert has been resolved.
       * @override
       */
      this.getText = function () {
        return alert.then(function (alert) {
          return alert.getText()
        })
      }
  
      /**
       * Defers action until the alert has been located.
       * @override
       */
      this.accept = function () {
        return alert.then(function (alert) {
          return alert.accept()
        })
      }
  
      /**
       * Defers action until the alert has been located.
       * @override
       */
      this.dismiss = function () {
        return alert.then(function (alert) {
          return alert.dismiss()
        })
      }
  
      /**
       * Defers action until the alert has been located.
       * @override
       */
      this.sendKeys = function (text) {
        return alert.then(function (alert) {
          return alert.sendKeys(text)
        })
      }
    }
  }
  
  // PUBLIC API
  
  module.exports = {
    Alert,
    AlertPromise,
    Condition,
    Logs,
    Navigation,
    Options,
    TargetLocator,
    IWebDriver,
    WebDriver,
    WebElement,
    WebElementCondition,
    WebElementPromise,
    Window,
  }
  