Update wmts-hidpi, add nicer-api-docs

nicer-api-docs/closure-library/closure/goog/ui/equation/imagerenderer.js

@@ -0,0 +1,190 @@
+// Copyright 2009 The Closure Library Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS-IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/**
+ * @fileoverview Functions for rendering the equation images.
+ *
+ */
+
+goog.provide('goog.ui.equation.ImageRenderer');
+
+goog.require('goog.dom.TagName');
+goog.require('goog.dom.classes');
+goog.require('goog.string');
+goog.require('goog.uri.utils');
+
+
+/**
+ * The server name which renders the equations.
+ * We use https as equations may be embedded in https pages
+ * and using https prevents mixed content warnings. Note that
+ * https equations work only on google.com domains.
+ * @type {string}
+ * @private
+ */
+goog.ui.equation.ImageRenderer.SERVER_NAME_ =
+    'https://www.google.com';
+
+
+/**
+ * The longest equation which may be displayed, in characters.
+ * @type {number}
+ */
+goog.ui.equation.ImageRenderer.MAX_EQUATION_LENGTH = 200;
+
+
+/**
+ * Class to put on our equations IMG elements.
+ * @type {string}
+ */
+goog.ui.equation.ImageRenderer.EE_IMG_CLASS = 'ee_img';
+
+
+/**
+ * Non-standard to put on our equations IMG elements. Useful when classes need
+ * to be scrubbed from the user-generated HTML, but non-standard attributes
+ * can be white-listed.
+ *
+ * @type {string}
+ */
+goog.ui.equation.ImageRenderer.EE_IMG_ATTR = 'eeimg';
+
+
+/**
+ * Vertical alignment for the equations IMG elements.
+ * @type {string}
+ */
+goog.ui.equation.ImageRenderer.EE_IMG_VERTICAL_ALIGN = 'middle';
+
+
+/**
+ * The default background color as used in the img url, which is fully
+ * transparent white.
+ * @type {string}
+ */
+goog.ui.equation.ImageRenderer.BACKGROUND_COLOR = 'FFFFFF00';
+
+
+/**
+ * The default foreground color as used in the img url, which is black.
+ * @type {string}
+ */
+goog.ui.equation.ImageRenderer.FOREGROUND_COLOR = '000000';
+
+
+/**
+ * Class to put on IMG elements to keep the resize property bubble from
+ * appearing. This is different from PLACEHOLDER_IMG_CLASS because it's
+ * reasonable in some cases to be able to resize a placeholder (which should
+ * be reflected when the placeholder is replaced with the other content).
+ * @type {string}
+ */
+goog.ui.equation.ImageRenderer.NO_RESIZE_IMG_CLASS =
+    goog.getCssName('tr_noresize');
+
+
+/**
+ * Returns the equation image src url given the equation.
+ * @param {string} equation The equation.
+ * @return {string} The equation image src url (empty string in case the
+ *   equation was empty).
+ */
+goog.ui.equation.ImageRenderer.getImageUrl = function(equation) {
+  if (!equation) {
+    return '';
+  }
+
+  var url = goog.ui.equation.ImageRenderer.SERVER_NAME_ +
+      '/chart?cht=tx' +
+      '&chf=bg,s,' +
+      goog.ui.equation.ImageRenderer.BACKGROUND_COLOR +
+      '&chco=' +
+      goog.ui.equation.ImageRenderer.FOREGROUND_COLOR +
+      '&chl=' +
+      encodeURIComponent(equation);
+  return url;
+};
+
+
+/**
+ * Returns the equation string src for given image url.
+ * @param {string} imageUrl The image url.
+ * @return {string?} The equation string, null if imageUrl cannot be parsed.
+ */
+goog.ui.equation.ImageRenderer.getEquationFromImageUrl = function(imageUrl) {
+  return goog.uri.utils.getParamValue(imageUrl, 'chl');
+};
+
+
+/**
+ * Gets the equation string from the given equation IMG node. Returns empty
+ * string if the src attribute of the is not a valid equation url.
+ * @param {Element} equationNode The equation IMG element.
+ * @return {string} The equation string.
+ */
+goog.ui.equation.ImageRenderer.getEquationFromImage = function(equationNode) {
+  var url = equationNode.getAttribute('src');
+  if (!url) {
+    // Should never happen.
+    return '';
+  }
+  return goog.ui.equation.ImageRenderer.getEquationFromImageUrl(
+      url) || '';
+};
+
+
+/**
+ * Checks whether given node is an equation element.
+ * @param {Node} node The node to check.
+ * @return {boolean} Whether given node is an equation element.
+ */
+goog.ui.equation.ImageRenderer.isEquationElement = function(node) {
+  return node.nodeName == goog.dom.TagName.IMG &&
+      (node.getAttribute(
+      goog.ui.equation.ImageRenderer.EE_IMG_ATTR) ||
+          goog.dom.classes.has(node,
+              goog.ui.equation.ImageRenderer.EE_IMG_CLASS));
+};
+
+
+/**
+ * Returns the html for the html image tag for the given equation.
+ * @param {string} equation The equation.
+ * @return {string} The html code to embed in the document.
+ */
+goog.ui.equation.ImageRenderer.getHtml = function(equation) {
+  var imageSrc =
+      goog.ui.equation.ImageRenderer.getImageUrl(equation);
+  if (!imageSrc) {
+    return '';
+  }
+  return '<img src="' + imageSrc + '" ' +
+      'alt="' + goog.string.htmlEscape(equation) + '" ' +
+      'class="' + goog.ui.equation.ImageRenderer.EE_IMG_CLASS +
+      ' ' + goog.ui.equation.ImageRenderer.NO_RESIZE_IMG_CLASS +
+      '" ' + goog.ui.equation.ImageRenderer.EE_IMG_ATTR + '="1" ' +
+      'style="vertical-align: ' +
+      goog.ui.equation.ImageRenderer.EE_IMG_VERTICAL_ALIGN + '">';
+};
+
+
+/**
+ * Checks whether equation is too long to be displayed.
+ * @param {string} equation The equation to test.
+ * @return {boolean} Whether the equation is too long.
+ */
+goog.ui.equation.ImageRenderer.isEquationTooLong = function(equation) {
+  return equation.length >
+      goog.ui.equation.ImageRenderer.MAX_EQUATION_LENGTH;
+};