UI refresh of Advanced Font Settings Extension

chrome/common/extensions/docs/examples/api/fontSettings/js/util.js

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-/**
- * The global object.
- * @type {!Object}
- * @const
- */
-var global = this;
-
-/**
- * Alias for document.getElementById.
- * @param {string} id The ID of the element to find.
- * @return {HTMLElement} The found element or null if not found.
- */
-function $(id) {
-  return document.getElementById(id);
-}
-
-/**
- * Calls chrome.send with a callback and restores the original afterwards.
- * @param {string} name The name of the message to send.
- * @param {!Array} params The parameters to send.
- * @param {string} callbackName The name of the function that the backend calls.
- * @param {!Function} callback The function to call.
- */
-function chromeSend(name, params, callbackName, callback) {
-  var old = global[callbackName];
-  global[callbackName] = function() {
-    // restore
-    global[callbackName] = old;
-
-    var args = Array.prototype.slice.call(arguments);
-    return callback.apply(global, args);
-  };
-  chrome.send(name, params);
-}
-
-/**
- * Generates a CSS url string.
- * @param {string} s The URL to generate the CSS url for.
- * @return {string} The CSS url string.
- */
-function url(s) {
-  // http://www.w3.org/TR/css3-values/#uris
-  // Parentheses, commas, whitespace characters, single quotes (') and double
-  // quotes (") appearing in a URI must be escaped with a backslash
-  var s2 = s.replace(/(\(|\)|\,|\s|\'|\"|\\)/g, '\\$1');
-  // WebKit has a bug when it comes to URLs that end with \
-  // https://bugs.webkit.org/show_bug.cgi?id=28885
-  if (/\\\\$/.test(s2)) {
-    // Add a space to work around the WebKit bug.
-    s2 += ' ';
-  }
-  return 'url("' + s2 + '")';
-}
-
-/**
- * Parses query parameters from Location.
- * @param {string} location The URL to generate the CSS url for.
- * @return {object} Dictionary containing name value pairs for URL
- */
-function parseQueryParams(location) {
-  var params = {};
-  var query = unescape(location.search.substring(1));
-  var vars = query.split('&');
-  for (var i = 0; i < vars.length; i++) {
-    var pair = vars[i].split('=');
-    params[pair[0]] = pair[1];
-  }
-  return params;
-}
-
-function findAncestorByClass(el, className) {
-  return findAncestor(el, function(el) {
-    if (el.classList)
-      return el.classList.contains(className);
-    return null;
-  });
-}
-
-/**
- * Return the first ancestor for which the {@code predicate} returns true.
- * @param {Node} node The node to check.
- * @param {function(Node) : boolean} predicate The function that tests the
- *     nodes.
- * @return {Node} The found ancestor or null if not found.
- */
-function findAncestor(node, predicate) {
-  var last = false;
-  while (node != null && !(last = predicate(node))) {
-    node = node.parentNode;
-  }
-  return last ? node : null;
-}
-
-function swapDomNodes(a, b) {
-  var afterA = a.nextSibling;
-  if (afterA == b) {
-    swapDomNodes(b, a);
-    return;
-  }
-  var aParent = a.parentNode;
-  b.parentNode.replaceChild(a, b);
-  aParent.insertBefore(b, afterA);
-}
-
-/**
- * Disables text selection and dragging, with optional whitelist callbacks.
- * @param {function(Event):boolean=} opt_allowSelectStart Unless this function
- *    is defined and returns true, the onselectionstart event will be
- *    surpressed.
- * @param {function(Event):boolean=} opt_allowDragStart Unless this function
- *    is defined and returns true, the ondragstart event will be surpressed.
- */
-function disableTextSelectAndDrag(opt_allowSelectStart, opt_allowDragStart) {
-  // Disable text selection.
-  document.onselectstart = function(e) {
-    if (!(opt_allowSelectStart && opt_allowSelectStart.call(this, e)))
-      e.preventDefault();
-  };
-
-  // Disable dragging.
-  document.ondragstart = function(e) {
-    if (!(opt_allowDragStart && opt_allowDragStart.call(this, e)))
-      e.preventDefault();
-  };
-}
-
-/**
- * Call this to stop clicks on <a href="#"> links from scrolling to the top of
- * the page (and possibly showing a # in the link).
- */
-function preventDefaultOnPoundLinkClicks() {
-  document.addEventListener('click', function(e) {
-    var anchor = findAncestor(e.target, function(el) {
-      return el.tagName == 'A';
-    });
-    // Use getAttribute() to prevent URL normalization.
-    if (anchor && anchor.getAttribute('href') == '#')
-      e.preventDefault();
-  });
-}
-
-/**
- * Check the directionality of the page.
- * @return {boolean} True if Chrome is running an RTL UI.
- */
-function isRTL() {
-  return document.documentElement.dir == 'rtl';
-}
-
-/**
- * Simple common assertion API
- * @param {*} condition The condition to test.  Note that this may be used to
- *     test whether a value is defined or not, and we don't want to force a
- *     cast to Boolean.
- * @param {string=} opt_message A message to use in any error.
- */
-function assert(condition, opt_message) {
-  'use strict';
-  if (!condition) {
-    var msg = 'Assertion failed';
-    if (opt_message)
-      msg = msg + ': ' + opt_message;
-    throw new Error(msg);
-  }
-}
-
-/**
- * Get an element that's known to exist by its ID. We use this instead of just
- * calling getElementById and not checking the result because this lets us
- * satisfy the JSCompiler type system.
- * @param {string} id The identifier name.
- * @return {!Element} the Element.
- */
-function getRequiredElement(id) {
-  var element = $(id);
-  assert(element, 'Missing required element: ' + id);
-  return element;
-}
-
-// Handle click on a link. If the link points to a chrome: or file: url, then
-// call into the browser to do the navigation.
-document.addEventListener('click', function(e) {
-  // Allow preventDefault to work.
-  if (!e.returnValue)
-    return;
-
-  var el = e.target;
-  if (el.nodeType == Node.ELEMENT_NODE &&
-      el.webkitMatchesSelector('A, A *')) {
-    while (el.tagName != 'A') {
-      el = el.parentElement;
-    }
-
-    if ((el.protocol == 'file:' || el.protocol == 'about:') &&
-        (e.button == 0 || e.button == 1)) {
-      chrome.send('navigateToUrl', [
-        el.href,
-        el.target,
-        e.button,
-        e.altKey,
-        e.ctrlKey,
-        e.metaKey,
-        e.shiftKey
-      ]);
-      e.preventDefault();
-    }
-  }
-});
-
-/**
- * Creates a new URL which is the old URL with a GET param of key=value.
- * @param {string} url The base URL. There is not sanity checking on the URL so
- *     it must be passed in a proper format.
- * @param {string} key The key of the param.
- * @param {string} value The value of the param.
- * @return {string} The new URL.
- */
-function appendParam(url, key, value) {
-  var param = encodeURIComponent(key) + '=' + encodeURIComponent(value);
-
-  if (url.indexOf('?') == -1)
-    return url + '?' + param;
-  return url + '&' + param;
-}