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

(function( exports, $ ){

	var api = wp.customize,

		Loader;

	$.extend( $.support, {

		history: !! ( window.history && history.pushState ),

		hashchange: ('onhashchange' in window) && (document.documentMode === undefined || document.documentMode > 7)

	});

	/**

	 * Allows the Customizer to be overlayed on any page.

	 *

	 * By default, any element in the body with the load-customize class will open

	 * an iframe overlay with the URL specified.

	 *

	 *     e.g. <a class="load-customize" href="<?php echo wp_customize_url(); ?>">Open Customizer</a>

	 *

	 * @augments wp.customize.Events

	 */

		/**

		 * Setup the Loader; triggered on document#ready.

		 */

		initialize: function() {

			this.body = $( document.body );

			// Ensure the loader is supported.

			// Check for settings, postMessage support, and whether we require CORS support.

			if ( ! Loader.settings || ! $.support.postMessage || ( ! $.support.cors && Loader.settings.isCrossDomain ) ) {

				return;

			}

			this.window  = $( window );

			this.element = $( '<div id="customize-container" />' ).appendTo( this.body );

			// Bind events for opening and closing the overlay.

			this.bind( 'open', this.overlay.show );

			this.bind( 'close', this.overlay.hide );

			// Any element in the body with the `load-customize` class opens

			// the Customizer.

			$('#wpbody').on( 'click', '.load-customize', function( event ) {

				event.preventDefault();

				// Store a reference to the link that opened the Customizer.

				Loader.link = $(this);

				// Load the theme.

				Loader.open( Loader.link.attr('href') );

			});

			// Add navigation listeners.

			if ( $.support.history ) {

				this.window.on( 'popstate', Loader.popstate );

			}

			if ( $.support.hashchange ) {

				this.window.on( 'hashchange', Loader.hashchange );

				this.window.triggerHandler( 'hashchange' );

			}

		},

		popstate: function( e ) {

			var state = e.originalEvent.state;

			if ( state && state.customize ) {

				Loader.open( state.customize );

			} else if ( Loader.active ) {

				Loader.close();

			}

		},

		hashchange: function() {

			var hash = window.location.toString().split('#')[1];

			if ( hash && 0 === hash.indexOf( 'wp_customize=on' ) ) {

				Loader.open( Loader.settings.url + '?' + hash );

			}

			if ( ! hash && ! $.support.history ) {

				Loader.close();

			}

		},

		beforeunload: function () {

			if ( ! Loader.saved() ) {

				return Loader.settings.l10n.saveAlert;

			}

		},

		/**

		 * Open the Customizer overlay for a specific URL.

		 *

		 * @param  string src URL to load in the Customizer.

		 */

		open: function( src ) {

			if ( this.active ) {

				return;

			}

			// Load the full page on mobile devices.

			if ( Loader.settings.browser.mobile ) {

				return window.location = src;

			}

			// Store the document title prior to opening the Live Preview

			this.originalDocumentTitle = document.title;

			this.active = true;

			this.body.addClass('customize-loading');

			this.saved = new api.Value( true );

			this.iframe = $( '<iframe />', { 'src': src, 'title': Loader.settings.l10n.mainIframeTitle } ).appendTo( this.element );

			this.iframe.one( 'load', this.loaded );

			// Create a postMessage connection with the iframe.

			this.messenger = new api.Messenger({

				url: src,

				channel: 'loader',

				targetWindow: this.iframe[0].contentWindow

			});

			// Wait for the connection from the iframe before sending any postMessage events.

			this.messenger.bind( 'ready', function() {

				Loader.messenger.send( 'back' );

			});

			this.messenger.bind( 'close', function() {

				if ( $.support.history ) {

					history.back();

				} else if ( $.support.hashchange ) {

					window.location.hash = '';

				} else {

					Loader.close();

				}

			});

			// Prompt AYS dialog when navigating away

			$( window ).on( 'beforeunload', this.beforeunload );

			this.messenger.bind( 'saved', function () {

				Loader.saved( true );

			} );

			this.messenger.bind( 'change', function () {

				Loader.saved( false );

			} );

			this.messenger.bind( 'title', function( newTitle ){

				window.document.title = newTitle;

			});

			this.pushState( src );

			this.trigger( 'open' );

		},

		pushState: function ( src ) {

			var hash = src.split( '?' )[1];

			// Ensure we don't call pushState if the user hit the forward button.

			if ( $.support.history && window.location.href !== src ) {

				history.pushState( { customize: src }, '', src );

			} else if ( ! $.support.history && $.support.hashchange && hash ) {

				window.location.hash = 'wp_customize=on&' + hash;

			}

			this.trigger( 'open' );

		},

		/**

		 * Callback after the Customizer has been opened.

		 */

		opened: function() {

		},

		/**

		 */

		close: function() {

				return;

			}

		},

		/**

		 * Callback after the Customizer has been closed.

		 */

		closed: function() {

			Loader.iframe.remove();

			Loader.messenger.destroy();

			Loader.iframe    = null;

			Loader.messenger = null;

			Loader.saved     = null;

			Loader.body.removeClass( 'customize-active full-overlay-active' ).removeClass( 'customize-loading' );

			$( window ).off( 'beforeunload', Loader.beforeunload );

		},

		/**

		 * Callback for the `load` event on the Customizer iframe.

		 */

		loaded: function() {

		},

		/**

		 * Overlay hide/show utility methods.

		 */

		overlay: {

			show: function() {

				this.element.fadeIn( 200, Loader.opened );

			},

			hide: function() {

				this.element.fadeOut( 200, Loader.closed );

			}

		}

	});

	// Bootstrap the Loader on document#ready.

	$( function() {

		Loader.settings = _wpCustomizeLoaderSettings;

		Loader.initialize();

	});

	// Expose the API publicly on window.wp.customize.Loader

	api.Loader = Loader;

})( wp, jQuery );