dom.js

/** @license MIT License (c) copyright B Cavalier & J Hann */

/**
 * wire/dom plugin
 * wire plugin that provides a resource resolver for dom nodes, by id, in the
 * current page.  This allows easy wiring of page-specific dom references into
 * generic components that may be page-independent, i.e. makes it easier to write
 * components that can be used on multiple pages, but still require a reference
 * to one or more nodes on the page.
 *
 * wire is part of the cujo.js family of libraries (http://cujojs.com/)
 *
 * Licensed under the MIT License at:
 * http://www.opensource.org/licenses/mit-license.php
 */

define(['wire/domReady'], function(domReady) {

    /**
     * Resolves a reference to a dom node on the page by its id
     *
     * @param resolver
     * @param name
     */
	function byId(resolver, name /*, refObj, wire*/) {
		domReady(function() {
			var node = document.getElementById(name);
			if(node) {
                resolver.resolve(node);
            } else {
                resolver.reject(new Error("No DOM node with id: " + name));
            }
		});
	}

    /**
     * The usual addClass function
     * 
     * @param node
     * @param cls {String} space separated list of classes
     */
	function addClass(node, cls) {
		var className = node.className ? ' ' + node.className + ' ' : '';
		
		cls = cls.split(/\s+/);
		
		for (var i = 0, len = cls.length; i < len; i++) {
			var c = ' ' + cls[i];
			if(className.indexOf(c + ' ') < 0) {
				className += c;
			}
		}

		node.className = className.slice(1, className.length);
	}

    /**
     * The usual removeClass function
     *
     * @param node
     * @param cls {String} space separated list of classes
     */
	function removeClass(node, cls) {
		var className = ' ' + node.className + ' ';

		cls = cls.split(/\s+/);

		for (var i = 0, len = cls.length; i < len; i++) {
			var c = ' ' + cls[i] + ' ';
			className = className.replace(c, ' ');
		}

		node.className = className.replace(/(^\s+|\s+$)/g, '');
	}

	function handleClasses(node, add, remove) {
		if(add) addClass(node, add);
		if(remove) removeClass(node, remove);
	}

    /**
     * Wire plugin. Since this plugin has no context-specific needs or
     * functionality, can always return the same object.
     */
	var wirePlugin = {
		resolvers: {
			dom: byId
		}		
	};

	return {
		wire$plugin: function domPlugin(ready, destroyed, options) {

			var node, classes;

			classes = options.classes;

			// Add/remove lifecycle classes if specified
			if(classes) {

				node = document.getElementsByTagName('html')[0];
				
				// Add classes for wiring start
				handleClasses(node, classes.init);

				// Add/remove classes for context ready
				ready.then(function() { handleClasses(node, classes.ready, classes.init); });

				if(classes.ready) {
					// Remove classes for context destroyed
					destroyed.then(function() { handleClasses(node, null, classes.ready); });
				}
			}

			// return the same instance every time, see above.
			return wirePlugin;
		}
	};

});