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js/goog/labs/useragent/util.js

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+/**
+ * @license
+ * Copyright The Closure Library Authors.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/**
+ * @fileoverview Utilities used by goog.labs.userAgent tools. These functions
+ * should not be used outside of goog.labs.userAgent.*.
+ *
+ */
+
+goog.module('goog.labs.userAgent.util');
+goog.module.declareLegacyNamespace();
+
+const {USE_CLIENT_HINTS} = goog.require('goog.labs.userAgent');
+const {caseInsensitiveContains, contains} = goog.require('goog.string.internal');
+
+/**
+ * @const {boolean} If true, use navigator.userAgentData without check.
+ * TODO(user) FEATURESET_YEAR >= 2022 if it supports mobile and all the
+ * brands we need.
+ */
+const ASSUME_CLIENT_HINTS_SUPPORT = false;
+
+/**
+ * Gets the native userAgent string from navigator if it exists.
+ * If navigator or navigator.userAgent string is missing, returns an empty
+ * string.
+ * @return {string}
+ */
+function getNativeUserAgentString() {
+  const navigator = getNavigator();
+  if (navigator) {
+    const userAgent = navigator.userAgent;
+    if (userAgent) {
+      return userAgent;
+    }
+  }
+  return '';
+}
+
+/**
+ * Gets the native userAgentData object from navigator if it exists.
+ * If navigator.userAgentData object is missing or USE_CLIENT_HINTS is set to
+ * false, returns null.
+ * @return {?NavigatorUAData}
+ */
+function getNativeUserAgentData() {
+  if (!USE_CLIENT_HINTS) {
+    return null;
+  }
+  const navigator = getNavigator();
+  // TODO(user): Use navigator?.userAgent ?? null once it's supported.
+  if (navigator) {
+    return navigator.userAgentData || null;
+  }
+  return null;
+}
+
+/**
+ * Getter for the native navigator.
+ * @return {!Navigator}
+ */
+function getNavigator() {
+  return goog.global.navigator;
+}
+
+/**
+ * A possible override for applications which wish to not check
+ * navigator.userAgent but use a specified value for detection instead.
+ * @type {string}
+ */
+let userAgentInternal = getNativeUserAgentString();
+
+/**
+ * A possible override for applications which wish to not check
+ * navigator.userAgentData but use a specified value for detection instead.
+ * @type {?NavigatorUAData}
+ */
+let userAgentDataInternal = getNativeUserAgentData();
+
+/**
+ * Override the user agent string with the given value.
+ * This should only be used for testing within the goog.labs.userAgent
+ * namespace.
+ * Pass `null` to use the native browser object instead.
+ * @param {?string=} userAgent The userAgent override.
+ * @return {void}
+ */
+function setUserAgent(userAgent = undefined) {
+  userAgentInternal =
+      typeof userAgent === 'string' ? userAgent : getNativeUserAgentString();
+}
+
+/** @return {string} The user agent string. */
+function getUserAgent() {
+  return userAgentInternal;
+}
+
+/**
+ * Override the user agent data object with the given value.
+ * This should only be used for testing within the goog.labs.userAgent
+ * namespace.
+ * Pass `null` to specify the absence of userAgentData. Note that this behavior
+ * is different from setUserAgent.
+ * @param {?NavigatorUAData} userAgentData The userAgentData override.
+ */
+function setUserAgentData(userAgentData) {
+  userAgentDataInternal = userAgentData;
+}
+
+/**
+ * If the user agent data object was overridden using setUserAgentData,
+ * reset it so that it uses the native browser object instead, if it exists.
+ */
+function resetUserAgentData() {
+  userAgentDataInternal = getNativeUserAgentData();
+}
+
+/** @return {?NavigatorUAData} Navigator.userAgentData if exist */
+function getUserAgentData() {
+  return userAgentDataInternal;
+}
+
+/**
+ * Checks if any string in userAgentData.brands matches str.
+ * Returns false if userAgentData is not supported.
+ * @param {string} str
+ * @return {boolean} Whether any brand string from userAgentData contains the
+ *     given string.
+ */
+function matchUserAgentDataBrand(str) {
+  const data = getUserAgentData();
+  if (!data) return false;
+  return data.brands.some(({brand}) => brand && contains(brand, str));
+}
+
+/**
+ * @param {string} str
+ * @return {boolean} Whether the user agent contains the given string.
+ */
+function matchUserAgent(str) {
+  const userAgent = getUserAgent();
+  return contains(userAgent, str);
+}
+
+/**
+ * @param {string} str
+ * @return {boolean} Whether the user agent contains the given string, ignoring
+ *     case.
+ */
+function matchUserAgentIgnoreCase(str) {
+  const userAgent = getUserAgent();
+  return caseInsensitiveContains(userAgent, str);
+}
+
+/**
+ * Parses the user agent into tuples for each section.
+ * @param {string} userAgent
+ * @return {!Array<!Array<string>>} Tuples of key, version, and the contents of
+ *     the parenthetical.
+ */
+function extractVersionTuples(userAgent) {
+  // Matches each section of a user agent string.
+  // Example UA:
+  // Mozilla/5.0 (iPad; U; CPU OS 3_2_1 like Mac OS X; en-us)
+  // AppleWebKit/531.21.10 (KHTML, like Gecko) Mobile/7B405
+  // This has three version tuples: Mozilla, AppleWebKit, and Mobile.
+
+  const versionRegExp = new RegExp(
+      // Key. Note that a key may have a space.
+      // (i.e. 'Mobile Safari' in 'Mobile Safari/5.0')
+      '(\\w[\\w ]+)' +
+
+          '/' +                // slash
+          '([^\\s]+)' +        // version (i.e. '5.0b')
+          '\\s*' +             // whitespace
+          '(?:\\((.*?)\\))?',  // parenthetical info. parentheses not matched.
+      'g');
+
+  const data = [];
+  let match;
+
+  // Iterate and collect the version tuples.  Each iteration will be the
+  // next regex match.
+  while (match = versionRegExp.exec(userAgent)) {
+    data.push([
+      match[1],  // key
+      match[2],  // value
+      // || undefined as this is not undefined in IE7 and IE8
+      match[3] || undefined  // info
+    ]);
+  }
+
+  return data;
+}
+
+exports = {
+  ASSUME_CLIENT_HINTS_SUPPORT,
+  extractVersionTuples,
+  getNativeUserAgentString,
+  getUserAgent,
+  getUserAgentData,
+  matchUserAgent,
+  matchUserAgentDataBrand,
+  matchUserAgentIgnoreCase,
+  resetUserAgentData,
+  setUserAgent,
+  setUserAgentData,
+};