/**

 * wp-emoji.js is used to replace emoji with images in browsers when the browser

 * doesn't support emoji natively.

 *

 * @output wp-includes/js/wp-emoji.js

 */

( function( window, settings ) {

	/**

	 * Replaces emoji with images when browsers don't support emoji.

	 *

	 *

	 * @class

	 *

	 * @see  Twitter Emoji library

	 * @link https://github.com/twitter/twemoji

	 *

	 * @return {Object} The wpEmoji parse and test functions.

	 */

	function wpEmoji() {

		var MutationObserver = window.MutationObserver || window.WebKitMutationObserver || window.MozMutationObserver,

		document = window.document,

		twemoji, timer,

		loaded = false,

		count = 0,

		ie11 = window.navigator.userAgent.indexOf( 'Trident/7.0' ) > 0;

		/**

		 * Detect if the browser supports SVG.

		 *

		 * @since 4.6.0

		 * @private

		 *

		 * @see Modernizr

		 * @link https://github.com/Modernizr/Modernizr/blob/master/feature-detects/svg/asimg.js

		 *

		 * @return {boolean} True if the browser supports svg, false if not.

		 */

		function browserSupportsSvgAsImage() {

			if ( !! document.implementation.hasFeature ) {

				return document.implementation.hasFeature( 'http://www.w3.org/TR/SVG11/feature#Image', '1.1' );

			}

			// document.implementation.hasFeature is deprecated. It can be presumed

			// if future browsers remove it, the browser will support SVGs as images.

			return true;

		}

		/**

		 * Runs when the document load event is fired, so we can do our first parse of

		 * the page.

		 *

		 * Listens to all the DOM mutations and checks for added nodes that contain

		 * emoji characters and replaces those with twitter emoji images.

		 *

		 * @since 4.2.0

		 * @private

		 */

		function load() {

			if ( loaded ) {

				return;

			}

			// Ensure twemoji is available on the global window before proceeding.

			if ( typeof window.twemoji === 'undefined' ) {

				if ( count > 600 ) {

					return;

				}

				// Still waiting.

				window.clearTimeout( timer );

				timer = window.setTimeout( load, 50 );

				count++;

				return;

			}

			twemoji = window.twemoji;

			loaded = true;

			// Initialize the mutation observer, which checks all added nodes for

			// replaceable emoji characters.

			if ( MutationObserver ) {

				new MutationObserver( function( mutationRecords ) {

					var i = mutationRecords.length,

						addedNodes, removedNodes, ii, node;

					while ( i-- ) {

						addedNodes = mutationRecords[ i ].addedNodes;

						removedNodes = mutationRecords[ i ].removedNodes;

						ii = addedNodes.length;

						/*

						 * Checks if an image has been replaced by a text element

						 * with the same text as the alternate description of the replaced image.

						 * (presumably because the image could not be loaded).

						 * If it is, do absolutely nothing.

						 *

						 * Node type 3 is a TEXT_NODE.

						 *

						 * @link https://developer.mozilla.org/en-US/docs/Web/API/Node/nodeType

						 */

						if (

							ii === 1 && removedNodes.length === 1 &&

							addedNodes[0].nodeType === 3 &&

							removedNodes[0].nodeName === 'IMG' &&

							addedNodes[0].data === removedNodes[0].alt &&

							'load-failed' === removedNodes[0].getAttribute( 'data-error' )

						) {

							return;

						}

						// Loop through all the added nodes.

						while ( ii-- ) {

							node = addedNodes[ ii ];

							// Node type 3 is a TEXT_NODE.

							if ( node.nodeType === 3 ) {

								if ( ! node.parentNode ) {

									continue;

								}

								if ( ie11 ) {

									/*

									 * IE 11's implementation of MutationObserver is buggy.

									 * It unnecessarily splits text nodes when it encounters a HTML

									 * template interpolation symbol ( "{{", for example ). So, we

									 * join the text nodes back together as a work-around.

									 *

									 * Node type 3 is a TEXT_NODE.

									 */

									while( node.nextSibling && 3 === node.nextSibling.nodeType ) {

										node.nodeValue = node.nodeValue + node.nextSibling.nodeValue;

										node.parentNode.removeChild( node.nextSibling );

									}

								}

								node = node.parentNode;

							}

							/*

							 * If the class name of a non-element node contains 'wp-exclude-emoji' ignore it.

							 *

							 * Node type 1 is an ELEMENT_NODE.

							 */

							if ( ! node || node.nodeType !== 1 ||

								( node.className && typeof node.className === 'string' && node.className.indexOf( 'wp-exclude-emoji' ) !== -1 ) ) {

								continue;

							}

							if ( test( node.textContent ) ) {

								parse( node );

							}

						}

					}

				} ).observe( document.body, {

					childList: true,

					subtree: true

				} );

			}

			parse( document.body );

		}

		/**

		 * Tests if a text string contains emoji characters.

		 *

		 * @since 4.3.0

		 *

		 * @memberOf wp.emoji

		 *

		 * @param {string} text The string to test.

		 *

		 * @return {boolean} Whether the string contains emoji characters.

		 */

		function test( text ) {

			// Single char. U+20E3 to detect keycaps. U+00A9 "copyright sign" and U+00AE "registered sign" not included.

			var single = /[\u203C\u2049\u20E3\u2122\u2139\u2194-\u2199\u21A9\u21AA\u2300\u231A\u231B\u2328\u2388\u23CF\u23E9-\u23F3\u23F8-\u23FA\u24C2\u25AA\u25AB\u25B6\u25C0\u25FB-\u25FE\u2600-\u2604\u260E\u2611\u2614\u2615\u2618\u261D\u2620\u2622\u2623\u2626\u262A\u262E\u262F\u2638\u2639\u263A\u2648-\u2653\u2660\u2663\u2665\u2666\u2668\u267B\u267F\u2692\u2693\u2694\u2696\u2697\u2699\u269B\u269C\u26A0\u26A1\u26AA\u26AB\u26B0\u26B1\u26BD\u26BE\u26C4\u26C5\u26C8\u26CE\u26CF\u26D1\u26D3\u26D4\u26E9\u26EA\u26F0-\u26F5\u26F7-\u26FA\u26FD\u2702\u2705\u2708-\u270D\u270F\u2712\u2714\u2716\u271D\u2721\u2728\u2733\u2734\u2744\u2747\u274C\u274E\u2753\u2754\u2755\u2757\u2763\u2764\u2795\u2796\u2797\u27A1\u27B0\u27BF\u2934\u2935\u2B05\u2B06\u2B07\u2B1B\u2B1C\u2B50\u2B55\u3030\u303D\u3297\u3299]/,

			// Surrogate pair range. Only tests for the second half.

			pair = /[\uDC00-\uDFFF]/;

			if ( text ) {

				return  pair.test( text ) || single.test( text );

			}

			return false;

		}

		/**

		 * Parses any emoji characters into Twemoji images.

		 *

		 * - When passed an element the emoji characters are replaced inline.

		 * - When passed a string the emoji characters are replaced and the result is

		 *   returned.

		 *

		 * @since 4.2.0

		 *

		 * @memberOf wp.emoji

		 *

		 * @param {HTMLElement|string} object The element or string to parse.

		 * @param {Object}             args   Additional options for Twemoji.

		 *

		 * @return {HTMLElement|string} A string where all emoji are now image tags of

		 *                              emoji. Or the element that was passed as the first argument.

		 */

		function parse( object, args ) {

			var params;

			/*

			 * If the browser has full support, twemoji is not loaded or our

			 * object is not what was expected, we do not parse anything.

			 */

			if ( settings.supports.everything || ! twemoji || ! object ||

				( 'string' !== typeof object && ( ! object.childNodes || ! object.childNodes.length ) ) ) {

				return object;

			}

			// Compose the params for the twitter emoji library.

			args = args || {};

			params = {

				base: browserSupportsSvgAsImage() ? settings.svgUrl : settings.baseUrl,

				ext:  browserSupportsSvgAsImage() ? settings.svgExt : settings.ext,

				className: args.className || 'emoji',

				callback: function( icon, options ) {

					// Ignore some standard characters that TinyMCE recommends in its character map.

					switch ( icon ) {

						case 'a9':

						case 'ae':

						case '2122':

						case '2194':

						case '2660':

						case '2663':

						case '2665':

						case '2666':

							return false;

					}

					if ( settings.supports.everythingExceptFlag &&

					) {

						return false;

					}

					return ''.concat( options.base, icon, options.ext );

				},

				onerror: function() {

					if ( twemoji.parentNode ) {

						this.setAttribute( 'data-error', 'load-failed' );

						twemoji.parentNode.replaceChild( document.createTextNode( twemoji.alt ), twemoji );

					}

				}

			};

			if ( typeof args.imgAttr === 'object' ) {

				params.attributes = function() {

					return args.imgAttr;

				};

			}

			return twemoji.parse( object, params );

		}

		/**

		 * Initialize our emoji support, and set up listeners.

		 */

		if ( settings ) {

			if ( settings.DOMReady ) {

				load();

			} else {

				settings.readyCallback = load;

			}

		}

		return {

			parse: parse,

			test: test

		};

	}

	window.wp = window.wp || {};

	/**

	 * @namespace wp.emoji

	 */

	window.wp.emoji = new wpEmoji();

} )( window, window._wpemojiSettings );