+/*
+ Copyright 2010 Google Inc.
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+*/
+
+/**
+ * @fileoverview Bookmark bubble library. This is meant to be included in the
+ * main JavaScript binary of a mobile web application.
+ *
+ * Supported browsers: iPhone / iPod / iPad Safari 3.0+
+ */
+
+var google = google || {};
+google.bookmarkbubble = google.bookmarkbubble || {};
+
+
+/**
+ * Binds a context object to the function.
+ * @param {Function} fn The function to bind to.
+ * @param {Object} context The "this" object to use when the function is run.
+ * @return {Function} A partially-applied form of fn.
+ */
+google.bind = function(fn, context) {
+ return function() {
+ return fn.apply(context, arguments);
+ };
+};
+
+
+/**
+ * Function used to define an abstract method in a base class. If a subclass
+ * fails to override the abstract method, then an error will be thrown whenever
+ * that method is invoked.
+ */
+google.abstractMethod = function() {
+ throw Error('Unimplemented abstract method.');
+};
+
+
+
+/**
+ * The bubble constructor. Instantiating an object does not cause anything to
+ * be rendered yet, so if necessary you can set instance properties before
+ * showing the bubble.
+ * @constructor
+ */
+google.bookmarkbubble.Bubble = function() {
+ /**
+ * Handler for the scroll event. Keep a reference to it here, so it can be
+ * unregistered when the bubble is destroyed.
+ * @type {function()}
+ * @private
+ */
+ this.boundScrollHandler_ = google.bind(this.setPosition, this);
+
+ /**
+ * The bubble element.
+ * @type {Element}
+ * @private
+ */
+ this.element_ = null;
+
+ /**
+ * Whether the bubble has been destroyed.
+ * @type {boolean}
+ * @private
+ */
+ this.hasBeenDestroyed_ = false;
+};
+
+
+/**
+ * Shows the bubble if allowed. It is not allowed if:
+ * - The browser is not Mobile Safari, or
+ * - The user has dismissed it too often already, or
+ * - The hash parameter is present in the location hash, or
+ * - The application is in fullscreen mode, which means it was already loaded
+ * from a homescreen bookmark.
+ * @return {boolean} True if the bubble is being shown, false if it is not
+ * allowed to show for one of the aforementioned reasons.
+ */
+google.bookmarkbubble.Bubble.prototype.showIfAllowed = function() {
+ if (!this.isAllowedToShow_()) {
+ return false;
+ }
+
+ this.show_();
+ return true;
+};
+
+
+/**
+ * Shows the bubble if allowed after loading the icon image. This method creates
+ * an image element to load the image into the browser's cache before showing
+ * the bubble to ensure that the image isn't blank. Use this instead of
+ * showIfAllowed if the image url is http and cacheable.
+ * This hack is necessary because Mobile Safari does not properly render
+ * image elements with border-radius CSS.
+ * @param {function()} opt_callback Closure to be called if and when the bubble
+ * actually shows.
+ * @return {boolean} True if the bubble is allowed to show.
+ */
+google.bookmarkbubble.Bubble.prototype.showIfAllowedWhenLoaded =
+ function(opt_callback) {
+ if (!this.isAllowedToShow_()) {
+ return false;
+ }
+
+ var self = this;
+ // Attach to self to avoid garbage collection.
+ var img = self.loadImg_ = document.createElement('img');
+ img.src = self.getIconUrl_();
+ img.onload = function() {
+ if (img.complete) {
+ delete self.loadImg_;
+ img.onload = null; // Break the circular reference.
+
+ self.show_();
+ opt_callback && opt_callback();
+ }
+ };
+ img.onload();
+
+ return true;
+};
+
+
+/**
+ * Sets the parameter in the location hash. As it is
+ * unpredictable what hash scheme is to be used, this method must be
+ * implemented by the host application.
+ *
+ * This gets called automatically when the bubble is shown. The idea is that if
+ * the user then creates a bookmark, we can later recognize on application
+ * startup whether it was from a bookmark suggested with this bubble.
+ */
+google.bookmarkbubble.Bubble.prototype.setHashParameter = google.abstractMethod;
+
+
+/**
+ * Whether the parameter is present in the location hash. As it is
+ * unpredictable what hash scheme is to be used, this method must be
+ * implemented by the host application.
+ *
+ * Call this method during application startup if you want to log whether the
+ * application was loaded from a bookmark with the bookmark bubble promotion
+ * parameter in it.
+ *
+ * @return {boolean} Whether the bookmark bubble parameter is present in the
+ * location hash.
+ */
+google.bookmarkbubble.Bubble.prototype.hasHashParameter = google.abstractMethod;
+
+
+/**
+ * The number of times the user must dismiss the bubble before we stop showing
+ * it. This is a public property and can be changed by the host application if
+ * necessary.
+ * @type {number}
+ */
+google.bookmarkbubble.Bubble.prototype.NUMBER_OF_TIMES_TO_DISMISS = 2;
+
+
+/**
+ * Time in milliseconds. If the user does not dismiss the bubble, it will auto
+ * destruct after this amount of time.
+ * @type {number}
+ */
+google.bookmarkbubble.Bubble.prototype.TIME_UNTIL_AUTO_DESTRUCT = 15000;
+
+
+/**
+ * The prefix for keys in local storage. This is a public property and can be
+ * changed by the host application if necessary.
+ * @type {string}
+ */
+google.bookmarkbubble.Bubble.prototype.LOCAL_STORAGE_PREFIX = 'BOOKMARK_';
+
+
+/**
+ * The key name for the dismissed state.
+ * @type {string}
+ * @private
+ */
+google.bookmarkbubble.Bubble.prototype.DISMISSED_ = 'DISMISSED_COUNT';
+
+
+/**
+ * The arrow image in base64 data url format.
+ * @type {string}
+ * @private
+ */
+google.bookmarkbubble.Bubble.prototype.IMAGE_ARROW_DATA_URL_ = 'data:image/png;base64,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';
+
+
+/**
+ * The close image in base64 data url format.
+ * @type {string}
+ * @private
+ */
+google.bookmarkbubble.Bubble.prototype.IMAGE_CLOSE_DATA_URL_ = 'data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQBAMAAADt3eJSAAAALVBMVEXM3fm+1Pfb5/rF2fjw9f23z/aavPOhwfTp8PyTt/L3+v7T4vqMs/K7zP////+qRWzhAAAAXElEQVQIW2O4CwUM996BwVskxtOqd++2rwMyPI+ve31GD8h4Madqz2mwms5jZ/aBGS/mHIDoen3m+DowY8/hOVUgxusz+zqPg7SvPA1UxQfSvu/du0YUK2AMmDMA5H1qhVX33T8AAAAASUVORK5CYII=';
+
+
+/**
+ * The link used to locate the application's home screen icon to display inside
+ * the bubble. The default link used here is for an iPhone home screen icon
+ * without gloss. If your application uses a glossy icon, change this to
+ * 'apple-touch-icon'.
+ * @type {string}
+ * @private
+ */
+google.bookmarkbubble.Bubble.prototype.REL_ICON_ =
+ 'apple-touch-icon-precomposed';
+
+
+/**
+ * Regular expression for detecting an iPhone or iPod or iPad.
+ * @type {!RegExp}
+ * @private
+ */
+google.bookmarkbubble.Bubble.prototype.MOBILE_SAFARI_USERAGENT_REGEX_ =
+ /iPhone|iPod|iPad/;
+
+
+/**
+ * Regular expression for detecting an iPad.
+ * @type {!RegExp}
+ * @private
+ */
+google.bookmarkbubble.Bubble.prototype.IPAD_USERAGENT_REGEX_ = /iPad/;
+
+
+/**
+ * Determines whether the bubble should be shown or not.
+ * @return {boolean} Whether the bubble should be shown or not.
+ * @private
+ */
+google.bookmarkbubble.Bubble.prototype.isAllowedToShow_ = function() {
+ return this.isMobileSafari_() &&
+ !this.hasBeenDismissedTooManyTimes_() &&
+ !this.isFullscreen_() &&
+ !this.hasHashParameter();
+};
+
+
+/**
+ * Builds and shows the bubble.
+ * @private
+ */
+google.bookmarkbubble.Bubble.prototype.show_ = function() {
+ this.element_ = this.build_();
+
+ document.body.appendChild(this.element_);
+ this.element_.style.WebkitTransform =
+ 'translateY(' + this.getHiddenYPosition_() + 'px)';
+
+ this.setHashParameter();
+
+ window.setTimeout(this.boundScrollHandler_, 1);
+ window.addEventListener('scroll', this.boundScrollHandler_, false);
+
+ // If the user does not dismiss the bubble, slide out and destroy it after
+ // some time.
+ window.setTimeout(google.bind(this.autoDestruct_, this),
+ this.TIME_UNTIL_AUTO_DESTRUCT);
+};
+
+
+/**
+ * Destroys the bubble by removing its DOM nodes from the document.
+ */
+google.bookmarkbubble.Bubble.prototype.destroy = function() {
+ if (this.hasBeenDestroyed_) {
+ return;
+ }
+ window.removeEventListener('scroll', this.boundScrollHandler_, false);
+ if (this.element_ && this.element_.parentNode == document.body) {
+ document.body.removeChild(this.element_);
+ this.element_ = null;
+ }
+ this.hasBeenDestroyed_ = true;
+};
+
+
+/**
+ * Remember that the user has dismissed the bubble once more.
+ * @private
+ */
+google.bookmarkbubble.Bubble.prototype.rememberDismissal_ = function() {
+ if (window.localStorage) {
+ try {
+ var key = this.LOCAL_STORAGE_PREFIX + this.DISMISSED_;
+ var value = Number(window.localStorage[key]) || 0;
+ window.localStorage[key] = String(value + 1);
+ } catch (ex) {
+ // Looks like we've hit the storage size limit. Currently we have no
+ // fallback for this scenario, but we could use cookie storage instead.
+ // This would increase the code bloat though.
+ }
+ }
+};
+
+
+/**
+ * Whether the user has dismissed the bubble often enough that we will not
+ * show it again.
+ * @return {boolean} Whether the user has dismissed the bubble often enough
+ * that we will not show it again.
+ * @private
+ */
+google.bookmarkbubble.Bubble.prototype.hasBeenDismissedTooManyTimes_ =
+ function() {
+ if (!window.localStorage) {
+ // If we can not use localStorage to remember how many times the user has
+ // dismissed the bubble, assume he has dismissed it. Otherwise we might end
+ // up showing it every time the host application loads, into eternity.
+ return true;
+ }
+ try {
+ var key = this.LOCAL_STORAGE_PREFIX + this.DISMISSED_;
+
+ // If the key has never been set, localStorage yields undefined, which
+ // Number() turns into NaN. In that case we'll fall back to zero for
+ // clarity's sake.
+ var value = Number(window.localStorage[key]) || 0;
+
+ return value >= this.NUMBER_OF_TIMES_TO_DISMISS;
+ } catch (ex) {
+ // If we got here, something is wrong with the localStorage. Make the same
+ // assumption as when it does not exist at all. Exceptions should only
+ // occur when setting a value (due to storage limitations) but let's be
+ // extra careful.
+ return true;
+ }
+};
+
+
+/**
+ * Whether the application is running in fullscreen mode.
+ * @return {boolean} Whether the application is running in fullscreen mode.
+ * @private
+ */
+google.bookmarkbubble.Bubble.prototype.isFullscreen_ = function() {
+ return !!window.navigator.standalone;
+};
+
+
+/**
+ * Whether the application is running inside Mobile Safari.
+ * @return {boolean} True if the current user agent looks like Mobile Safari.
+ * @private
+ */
+google.bookmarkbubble.Bubble.prototype.isMobileSafari_ = function() {
+ return this.MOBILE_SAFARI_USERAGENT_REGEX_.test(window.navigator.userAgent);
+};
+
+
+/**
+ * Whether the application is running on an iPad.
+ * @return {boolean} True if the current user agent looks like an iPad.
+ * @private
+ */
+google.bookmarkbubble.Bubble.prototype.isIpad_ = function() {
+ return this.IPAD_USERAGENT_REGEX_.test(window.navigator.userAgent);
+};
+
+
+
+/**
+ * Positions the bubble at the bottom of the viewport using an animated
+ * transition.
+ */
+google.bookmarkbubble.Bubble.prototype.setPosition = function() {
+ this.element_.style.WebkitTransition = '-webkit-transform 0.7s ease-out';
+ this.element_.style.WebkitTransform =
+ 'translateY(' + this.getVisibleYPosition_() + 'px)';
+};
+
+
+/**
+ * Destroys the bubble by removing its DOM nodes from the document, and
+ * remembers that it was dismissed.
+ * @private
+ */
+google.bookmarkbubble.Bubble.prototype.closeClickHandler_ = function() {
+ this.destroy();
+ this.rememberDismissal_();
+};
+
+
+/**
+ * Gets called after a while if the user ignores the bubble.
+ * @private
+ */
+google.bookmarkbubble.Bubble.prototype.autoDestruct_ = function() {
+ if (this.hasBeenDestroyed_) {
+ return;
+ }
+ this.element_.style.WebkitTransition = '-webkit-transform 0.7s ease-in';
+ this.element_.style.WebkitTransform =
+ 'translateY(' + this.getHiddenYPosition_() + 'px)';
+ window.setTimeout(google.bind(this.destroy, this), 700);
+};
+
+
+/**
+ * Gets the y offset used to show the bubble (i.e., position it on-screen).
+ * @return {number} The y offset.
+ * @private
+ */
+google.bookmarkbubble.Bubble.prototype.getVisibleYPosition_ = function() {
+ return this.isIpad_() ? window.pageYOffset + 17 :
+ window.pageYOffset - this.element_.offsetHeight + window.innerHeight - 17;
+};
+
+
+/**
+ * Gets the y offset used to hide the bubble (i.e., position it off-screen).
+ * @return {number} The y offset.
+ * @private
+ */
+google.bookmarkbubble.Bubble.prototype.getHiddenYPosition_ = function() {
+ return this.isIpad_() ? window.pageYOffset - this.element_.offsetHeight :
+ window.pageYOffset + window.innerHeight;
+};
+
+
+/**
+ * The url of the app's bookmark icon.
+ * @type {string|undefined}
+ * @private
+ */
+google.bookmarkbubble.Bubble.prototype.iconUrl_;
+
+
+/**
+ * Scrapes the document for a link element that specifies an Apple favicon and
+ * returns the icon url. Returns an empty data url if nothing can be found.
+ * @return {string} A url string.
+ * @private
+ */
+google.bookmarkbubble.Bubble.prototype.getIconUrl_ = function() {
+ if (!this.iconUrl_) {
+ var link = this.getLink(this.REL_ICON_);
+ if (!link || !(this.iconUrl_ = link.href)) {
+ this.iconUrl_ = 'data:image/png;base64,';
+ }
+ }
+ return this.iconUrl_;
+};
+
+
+/**
+ * Gets the requested link tag if it exists.
+ * @param {string} rel The rel attribute of the link tag to get.
+ * @return {Element} The requested link tag or null.
+ */
+google.bookmarkbubble.Bubble.prototype.getLink = function(rel) {
+ rel = rel.toLowerCase();
+ var links = document.getElementsByTagName('link');
+ for (var i = 0; i < links.length; ++i) {
+ var currLink = /** @type {Element} */ (links[i]);
+ if (currLink.getAttribute('rel').toLowerCase() == rel) {
+ return currLink;
+ }
+ }
+ return null;
+};
+
+
+/**
+ * Creates the bubble and appends it to the document.
+ * @return {Element} The bubble element.
+ * @private
+ */
+google.bookmarkbubble.Bubble.prototype.build_ = function() {
+ var bubble = document.createElement('div');
+ var isIpad = this.isIpad_();
+
+ bubble.style.position = 'absolute';
+ bubble.style.zIndex = 1000;
+ bubble.style.width = '100%';
+ bubble.style.left = '0';
+ bubble.style.top = '0';
+
+ var bubbleInner = document.createElement('div');
+ bubbleInner.style.position = 'relative';
+ bubbleInner.style.width = '214px';
+ bubbleInner.style.margin = isIpad ? '0 0 0 82px' : '0 auto';
+ bubbleInner.style.border = '2px solid #fff';
+ bubbleInner.style.padding = '20px 20px 20px 10px';
+ bubbleInner.style.WebkitBorderRadius = '8px';
+ bubbleInner.style.WebkitBoxShadow = '0 0 8px rgba(0, 0, 0, 0.7)';
+ bubbleInner.style.WebkitBackgroundSize = '100% 8px';
+ bubbleInner.style.backgroundColor = '#b0c8ec';
+ bubbleInner.style.background = '#cddcf3 -webkit-gradient(linear, ' +
+ 'left bottom, left top, ' + isIpad ?
+ 'from(#cddcf3), to(#b3caed)) no-repeat top' :
+ 'from(#b3caed), to(#cddcf3)) no-repeat bottom';
+ bubbleInner.style.font = '13px/17px sans-serif';
+ bubble.appendChild(bubbleInner);
+
+ // The "Add to Home Screen" text is intended to be the exact same size text
+ // that is displayed in the menu of Mobile Safari on iPhone.
+ bubbleInner.innerHTML = 'Install this web app on your phone: tap ' +
+ '<b style="font-size:15px">+</b> and then <b>\'Add to Home Screen\'</b>';
+
+ var icon = document.createElement('div');
+ icon.style['float'] = 'left';
+ icon.style.width = '55px';
+ icon.style.height = '55px';
+ icon.style.margin = '-2px 7px 3px 5px';
+ icon.style.background =
+ '#fff url(' + this.getIconUrl_() + ') no-repeat -1px -1px';
+ icon.style.WebkitBackgroundSize = '57px';
+ icon.style.WebkitBorderRadius = '10px';
+ icon.style.WebkitBoxShadow = '0 2px 5px rgba(0, 0, 0, 0.4)';
+ bubbleInner.insertBefore(icon, bubbleInner.firstChild);
+
+ var arrow = document.createElement('div');
+ arrow.style.backgroundImage = 'url(' + this.IMAGE_ARROW_DATA_URL_ + ')';
+ arrow.style.width = '25px';
+ arrow.style.height = '19px';
+ arrow.style.position = 'absolute';
+ arrow.style.left = '111px';
+ if (isIpad) {
+ arrow.style.WebkitTransform = 'rotate(180deg)';
+ arrow.style.top = '-19px';
+ } else {
+ arrow.style.bottom = '-19px';
+ }
+ bubbleInner.appendChild(arrow);
+
+ var close = document.createElement('a');
+ close.onclick = google.bind(this.closeClickHandler_, this);
+ close.style.position = 'absolute';
+ close.style.display = 'block';
+ close.style.top = '-3px';
+ close.style.right = '-3px';
+ close.style.width = '16px';
+ close.style.height = '16px';
+ close.style.border = '10px solid transparent';
+ close.style.background =
+ 'url(' + this.IMAGE_CLOSE_DATA_URL_ + ') no-repeat';
+ bubbleInner.appendChild(close);
+
+ return bubble;
+};