Update to the correct 2.0 release

Signed-off-by: Charlie Gracie <charlie.gracie@gmail.com>

js/retina.js

@@ -1,3 +1,218 @@
-// retina.js, a high-resolution image swapper (http://retinajs.com), v0.0.2
+/*!
+ * Retina.js v2.0.0
+ *
+ * Copyright 2016 Axial, LLC
+ * Released under the MIT license
+ *
+ * Retina.js is an open source script that makes it easy to serve
+ * high-resolution images to devices with retina displays.
+ */
+'use strict';
 
-(function(){function t(e){this.path=e;var t=this.path.split("."),n=t.slice(0,t.length-1).join("."),r=t[t.length-1];this.at_2x_path=n+"@2x."+r}function n(e){this.el=e,this.path=new t(this.el.getAttribute("src"));var n=this;this.path.check_2x_variant(function(e){e&&n.swap()})}var e=typeof exports=="undefined"?window:exports;e.RetinaImagePath=t,t.confirmed_paths=[],t.prototype.is_external=function(){return!!this.path.match(/^https?\:/i)&&!this.path.match("//"+document.domain)},t.prototype.check_2x_variant=function(e){var n,r=this;if(this.is_external())return e(!1);if(this.at_2x_path in t.confirmed_paths)return e(!0);n=new XMLHttpRequest,n.open("HEAD",this.at_2x_path),n.onreadystatechange=function(){return n.readyState!=4?e(!1):n.status>=200&&n.status<=399?(t.confirmed_paths.push(r.at_2x_path),e(!0)):e(!1)},n.send()},e.RetinaImage=n,n.prototype.swap=function(e){function n(){t.el.complete?(t.el.setAttribute("width",t.el.offsetWidth),t.el.setAttribute("height",t.el.offsetHeight),t.el.setAttribute("src",e)):setTimeout(n,5)}typeof e=="undefined"&&(e=this.path.at_2x_path);var t=this;n()},e.devicePixelRatio>1&&(window.onload=function(){var e=document.getElementsByTagName("img"),t=[],r,i;for(r=0;r<e.length;r++)i=e[r],t.push(new n(i))})})();
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+/*
+ * Determine whether or not `window` is available.
+ */
+var hasWindow = typeof window !== 'undefined';
+
+/*
+ * Get the device pixel ratio per our environment.
+ * Default to 1.
+ */
+var environment = hasWindow ? window.devicePixelRatio || 1 : 1;
+
+/*
+ * Define a pattern for capturing src url suffixes.
+ */
+var srcReplace = /(\.[A-z]{3,4}\/?(\?.*)?)$/;
+var inlineReplace = /url\(('|")?([^\)'"]+)('|")?\)/i;
+
+/*
+ * Define our selectors for elements to target.
+ */
+var selector = '[data-rjs]';
+
+/**
+ * Chooses the actual image size to fetch, (for example 2 or 3) that
+ * will be used to create a suffix like "@2x" or "@3x".
+ *
+ * @param  {String|Number} cap The number the user provided indicating that
+ *                             they have prepared images up to this size.
+ *
+ * @return {Number} The number we'll be using to create a suffix.
+ */
+function chooseCap(cap) {
+  var numericCap = parseInt(cap, 10);
+
+  /*
+   * If the environment's device pixel ratio is less than what the user
+   * provided, we'll only grab images at that size.
+   */
+  if (environment < numericCap) {
+    return environment;
+
+    /*
+     * If the device pixel ratio is greater than or equal to what the
+     * user provided, we'll use what the user provided.
+     */
+  } else {
+      return numericCap;
+    }
+}
+
+/**
+ * Makes sure that, since we are going to swap out the source of an image,
+ * the image does not change size on the page.
+ *
+ * @param  {Element} image An image element in the DOM.
+ *
+ * @return {Element} The same element that was passed in.
+ */
+function forceOriginalDimensions(image) {
+  if (!image.hasAttribute('data-no-resize')) {
+    if (image.offsetWidth === 0 && image.offsetHeight === 0) {
+      image.setAttribute('width', image.naturalWidth);
+      image.setAttribute('height', image.naturalHeight);
+    } else {
+      image.setAttribute('width', image.offsetWidth);
+      image.setAttribute('height', image.offsetHeight);
+    }
+  }
+  return image;
+}
+
+/**
+ * Determines whether the retina image actually exists on the server.
+ * If so, swaps out the retina image for the standard one. If not,
+ * leaves the original image alone.
+ *
+ * @param {Element} image  An image element in the DOM.
+ * @param {String}  newSrc The url to the retina image.
+ *
+ * @return {undefined}
+ */
+function setSourceIfAvailable(image, retinaURL) {
+  var imgType = image.nodeName.toLowerCase();
+
+  /*
+   * Create a new image element and give it a load listener. When the
+   * load listener fires, it means the URL is correct and we will then
+   * attach it to the user's image.
+   */
+  var testImage = document.createElement('img');
+  testImage.addEventListener('load', function () {
+    /*
+     * If we're dealing with an image tag, force it's dimensions
+     * and set the source attribute. If not, go after the background-image
+     * inline style.
+     */
+    if (imgType === 'img') {
+      forceOriginalDimensions(image).setAttribute('src', retinaURL);
+    } else {
+      image.style.backgroundImage = 'url(' + retinaURL + ')';
+    }
+  });
+
+  /*
+   * Attach the retina URL to our proxy image to load in the new
+   * image resource.
+   */
+  testImage.setAttribute('src', retinaURL);
+}
+
+/**
+ * Attempts to do an image url swap on a given image.
+ *
+ * @param  {Element}       image An image in the DOM.
+ * @param  {String}        src   The original image source attribute.
+ * @param  {String|Number} rjs   The pixel density cap for images provided.
+ *
+ * @return {undefined}
+ */
+function dynamicSwapImage(image, src) {
+  var rjs = arguments.length <= 2 || arguments[2] === undefined ? 1 : arguments[2];
+
+  var cap = chooseCap(rjs);
+
+  /*
+   * Don't do anything if the cap is less than 2 or there is no src.
+   */
+  if (src && cap > 1) {
+    var newSrc = src.replace(srcReplace, '@' + cap + 'x$1');
+    setSourceIfAvailable(image, newSrc);
+  }
+}
+
+/**
+ * Performs an image url swap on a given image with a provided url.
+ *
+ * @param  {Element} image  An image in the DOM.
+ * @param  {String}  src    The original image source attribute.
+ * @param  {String}  hdsrc  The path for a 2x image.
+ *
+ * @return {undefined}
+ */
+function manualSwapImage(image, src, hdsrc) {
+  if (environment > 1) {
+    setSourceIfAvailable(image, hdsrc);
+  }
+}
+
+/**
+ * Collects all images matching our selector, and converts our
+ * NodeList into an Array so that Array methods will be available to it.
+ *
+ * @return {Array} Contains all elements matching our selector.
+ */
+function getImages() {
+  return typeof document !== 'undefined' ? Array.prototype.slice.call(document.querySelectorAll(selector)) : [];
+}
+
+/**
+ * Converts a string like "url(hello.png)" into "hello.png".
+ *
+ * @param  {Element} img An HTML element with a background image.
+ *
+ * @return {String}
+ */
+function cleanBgImg(img) {
+  return img.style.backgroundImage.replace(inlineReplace, '$2');
+}
+
+/**
+ * Gets all participating images and dynamically swaps out each one for its
+ * retina equivalent taking into account the environment capabilities and
+ * the densities for which the user has provided images.
+ *
+ * @return {undefined}
+ */
+function retina() {
+  getImages().forEach(function (img) {
+    var isImg = img.nodeName.toLowerCase() === 'img';
+    var src = isImg ? img.getAttribute('src') : cleanBgImg(img);
+    var rjs = img.getAttribute('data-rjs');
+    var rjsIsNumber = !isNaN(parseInt(rjs, 10));
+
+    /*
+     * If the user provided a number, dynamically swap out the image.
+     * If the user provided a url, do it manually.
+     */
+    if (rjsIsNumber) {
+      dynamicSwapImage(img, src, rjs);
+    } else {
+      manualSwapImage(img, src, rjs);
+    }
+  });
+}
+
+/*
+ * If this environment has `window`, activate the plugin.
+ */
+if (hasWindow) {
+  window.addEventListener('load', retina);
+  window.retinajs = retina;
+}
+
+exports.default = retina;