wp/wp-includes/js/customize-preview.js
changeset 7 cf61fcea0001
parent 5 5e2f62d02dcd
child 9 177826044cd9
equal deleted inserted replaced
6:490d5cc509ed 7:cf61fcea0001
       
     1 /*
       
     2  * Script run inside a Customizer preview frame.
       
     3  */
     1 (function( exports, $ ){
     4 (function( exports, $ ){
     2 	var api = wp.customize,
     5 	var api = wp.customize,
     3 		debounce;
     6 		debounce,
       
     7 		currentHistoryState = {};
       
     8 
       
     9 	/*
       
    10 	 * Capture the state that is passed into history.replaceState() and history.pushState()
       
    11 	 * and also which is returned in the popstate event so that when the changeset_uuid
       
    12 	 * gets updated when transitioning to a new changeset there the current state will
       
    13 	 * be supplied in the call to history.replaceState().
       
    14 	 */
       
    15 	( function( history ) {
       
    16 		var injectUrlWithState;
       
    17 
       
    18 		if ( ! history.replaceState ) {
       
    19 			return;
       
    20 		}
       
    21 
       
    22 		/**
       
    23 		 * Amend the supplied URL with the customized state.
       
    24 		 *
       
    25 		 * @since 4.7.0
       
    26 		 * @access private
       
    27 		 *
       
    28 		 * @param {string} url URL.
       
    29 		 * @returns {string} URL with customized state.
       
    30 		 */
       
    31 		injectUrlWithState = function( url ) {
       
    32 			var urlParser, oldQueryParams, newQueryParams;
       
    33 			urlParser = document.createElement( 'a' );
       
    34 			urlParser.href = url;
       
    35 			oldQueryParams = api.utils.parseQueryString( location.search.substr( 1 ) );
       
    36 			newQueryParams = api.utils.parseQueryString( urlParser.search.substr( 1 ) );
       
    37 
       
    38 			newQueryParams.customize_changeset_uuid = oldQueryParams.customize_changeset_uuid;
       
    39 			if ( oldQueryParams.customize_autosaved ) {
       
    40 				newQueryParams.customize_autosaved = 'on';
       
    41 			}
       
    42 			if ( oldQueryParams.customize_theme ) {
       
    43 				newQueryParams.customize_theme = oldQueryParams.customize_theme;
       
    44 			}
       
    45 			if ( oldQueryParams.customize_messenger_channel ) {
       
    46 				newQueryParams.customize_messenger_channel = oldQueryParams.customize_messenger_channel;
       
    47 			}
       
    48 			urlParser.search = $.param( newQueryParams );
       
    49 			return urlParser.href;
       
    50 		};
       
    51 
       
    52 		history.replaceState = ( function( nativeReplaceState ) {
       
    53 			return function historyReplaceState( data, title, url ) {
       
    54 				currentHistoryState = data;
       
    55 				return nativeReplaceState.call( history, data, title, 'string' === typeof url && url.length > 0 ? injectUrlWithState( url ) : url );
       
    56 			};
       
    57 		} )( history.replaceState );
       
    58 
       
    59 		history.pushState = ( function( nativePushState ) {
       
    60 			return function historyPushState( data, title, url ) {
       
    61 				currentHistoryState = data;
       
    62 				return nativePushState.call( history, data, title, 'string' === typeof url && url.length > 0 ? injectUrlWithState( url ) : url );
       
    63 			};
       
    64 		} )( history.pushState );
       
    65 
       
    66 		window.addEventListener( 'popstate', function( event ) {
       
    67 			currentHistoryState = event.state;
       
    68 		} );
       
    69 
       
    70 	}( history ) );
     4 
    71 
     5 	/**
    72 	/**
     6 	 * Returns a debounced version of the function.
    73 	 * Returns a debounced version of the function.
     7 	 *
    74 	 *
     8 	 * @todo Require Underscore.js for this file and retire this.
    75 	 * @todo Require Underscore.js for this file and retire this.
    21 			}, delay );
    88 			}, delay );
    22 		};
    89 		};
    23 	};
    90 	};
    24 
    91 
    25 	/**
    92 	/**
       
    93 	 * @memberOf wp.customize
       
    94 	 * @alias wp.customize.Preview
       
    95 	 *
    26 	 * @constructor
    96 	 * @constructor
    27 	 * @augments wp.customize.Messenger
    97 	 * @augments wp.customize.Messenger
    28 	 * @augments wp.customize.Class
    98 	 * @augments wp.customize.Class
    29 	 * @mixes wp.customize.Events
    99 	 * @mixes wp.customize.Events
    30 	 */
   100 	 */
    31 	api.Preview = api.Messenger.extend({
   101 	api.Preview = api.Messenger.extend(/** @lends wp.customize.Preview.prototype */{
    32 		/**
   102 		/**
    33 		 * Requires params:
   103 		 * @param {object} params  - Parameters to configure the messenger.
    34 		 *  - url    - the URL of preview frame
   104 		 * @param {object} options - Extend any instance parameter or method with this object.
    35 		 */
   105 		 */
    36 		initialize: function( params, options ) {
   106 		initialize: function( params, options ) {
    37 			var self = this;
   107 			var preview = this, urlParser = document.createElement( 'a' );
    38 
   108 
    39 			api.Messenger.prototype.initialize.call( this, params, options );
   109 			api.Messenger.prototype.initialize.call( preview, params, options );
    40 
   110 
    41 			this.body = $( document.body );
   111 			urlParser.href = preview.origin();
    42 			this.body.on( 'click.preview', 'a', function( event ) {
   112 			preview.add( 'scheme', urlParser.protocol.replace( /:$/, '' ) );
       
   113 
       
   114 			preview.body = $( document.body );
       
   115 			preview.window = $( window );
       
   116 
       
   117 			if ( api.settings.channel ) {
       
   118 
       
   119 				// If in an iframe, then intercept the link clicks and form submissions.
       
   120 				preview.body.on( 'click.preview', 'a', function( event ) {
       
   121 					preview.handleLinkClick( event );
       
   122 				} );
       
   123 				preview.body.on( 'submit.preview', 'form', function( event ) {
       
   124 					preview.handleFormSubmit( event );
       
   125 				} );
       
   126 
       
   127 				preview.window.on( 'scroll.preview', debounce( function() {
       
   128 					preview.send( 'scroll', preview.window.scrollTop() );
       
   129 				}, 200 ) );
       
   130 
       
   131 				preview.bind( 'scroll', function( distance ) {
       
   132 					preview.window.scrollTop( distance );
       
   133 				});
       
   134 			}
       
   135 		},
       
   136 
       
   137 		/**
       
   138 		 * Handle link clicks in preview.
       
   139 		 *
       
   140 		 * @since 4.7.0
       
   141 		 * @access public
       
   142 		 *
       
   143 		 * @param {jQuery.Event} event Event.
       
   144 		 */
       
   145 		handleLinkClick: function( event ) {
       
   146 			var preview = this, link, isInternalJumpLink;
       
   147 			link = $( event.target ).closest( 'a' );
       
   148 
       
   149 			// No-op if the anchor is not a link.
       
   150 			if ( _.isUndefined( link.attr( 'href' ) ) ) {
       
   151 				return;
       
   152 			}
       
   153 
       
   154 			// Allow internal jump links and JS links to behave normally without preventing default.
       
   155 			isInternalJumpLink = ( '#' === link.attr( 'href' ).substr( 0, 1 ) );
       
   156 			if ( isInternalJumpLink || ! /^https?:$/.test( link.prop( 'protocol' ) ) ) {
       
   157 				return;
       
   158 			}
       
   159 
       
   160 			// If the link is not previewable, prevent the browser from navigating to it.
       
   161 			if ( ! api.isLinkPreviewable( link[0] ) ) {
       
   162 				wp.a11y.speak( api.settings.l10n.linkUnpreviewable );
    43 				event.preventDefault();
   163 				event.preventDefault();
    44 				self.send( 'scroll', 0 );
   164 				return;
    45 				self.send( 'url', $(this).prop('href') );
   165 			}
    46 			});
   166 
    47 
   167 			// Prevent initiating navigating from click and instead rely on sending url message to pane.
    48 			// You cannot submit forms.
   168 			event.preventDefault();
    49 			// @todo: Allow form submissions by mixing $_POST data with the customize setting $_POST data.
   169 
    50 			this.body.on( 'submit.preview', 'form', function( event ) {
   170 			/*
       
   171 			 * Note the shift key is checked so shift+click on widgets or
       
   172 			 * nav menu items can just result on focusing on the corresponding
       
   173 			 * control instead of also navigating to the URL linked to.
       
   174 			 */
       
   175 			if ( event.shiftKey ) {
       
   176 				return;
       
   177 			}
       
   178 
       
   179 			// Note: It's not relevant to send scroll because sending url message will have the same effect.
       
   180 			preview.send( 'url', link.prop( 'href' ) );
       
   181 		},
       
   182 
       
   183 		/**
       
   184 		 * Handle form submit.
       
   185 		 *
       
   186 		 * @since 4.7.0
       
   187 		 * @access public
       
   188 		 *
       
   189 		 * @param {jQuery.Event} event Event.
       
   190 		 */
       
   191 		handleFormSubmit: function( event ) {
       
   192 			var preview = this, urlParser, form;
       
   193 			urlParser = document.createElement( 'a' );
       
   194 			form = $( event.target );
       
   195 			urlParser.href = form.prop( 'action' );
       
   196 
       
   197 			// If the link is not previewable, prevent the browser from navigating to it.
       
   198 			if ( 'GET' !== form.prop( 'method' ).toUpperCase() || ! api.isLinkPreviewable( urlParser ) ) {
       
   199 				wp.a11y.speak( api.settings.l10n.formUnpreviewable );
    51 				event.preventDefault();
   200 				event.preventDefault();
    52 			});
   201 				return;
    53 
   202 			}
    54 			this.window = $( window );
   203 
    55 			this.window.on( 'scroll.preview', debounce( function() {
   204 			/*
    56 				self.send( 'scroll', self.window.scrollTop() );
   205 			 * If the default wasn't prevented already (in which case the form
    57 			}, 200 ));
   206 			 * submission is already being handled by JS), and if it has a GET
    58 
   207 			 * request method, then take the serialized form data and add it as
    59 			this.bind( 'scroll', function( distance ) {
   208 			 * a query string to the action URL and send this in a url message
    60 				self.window.scrollTop( distance );
   209 			 * to the customizer pane so that it will be loaded. If the form's
    61 			});
   210 			 * action points to a non-previewable URL, the customizer pane's
       
   211 			 * previewUrl setter will reject it so that the form submission is
       
   212 			 * a no-op, which is the same behavior as when clicking a link to an
       
   213 			 * external site in the preview.
       
   214 			 */
       
   215 			if ( ! event.isDefaultPrevented() ) {
       
   216 				if ( urlParser.search.length > 1 ) {
       
   217 					urlParser.search += '&';
       
   218 				}
       
   219 				urlParser.search += form.serialize();
       
   220 				preview.send( 'url', urlParser.href );
       
   221 			}
       
   222 
       
   223 			// Prevent default since navigation should be done via sending url message or via JS submit handler.
       
   224 			event.preventDefault();
    62 		}
   225 		}
    63 	});
   226 	});
    64 
   227 
       
   228 	/**
       
   229 	 * Inject the changeset UUID into links in the document.
       
   230 	 *
       
   231 	 * @since 4.7.0
       
   232 	 * @access protected
       
   233 	 *
       
   234 	 * @access private
       
   235 	 * @returns {void}
       
   236 	 */
       
   237 	api.addLinkPreviewing = function addLinkPreviewing() {
       
   238 		var linkSelectors = 'a[href], area';
       
   239 
       
   240 		// Inject links into initial document.
       
   241 		$( document.body ).find( linkSelectors ).each( function() {
       
   242 			api.prepareLinkPreview( this );
       
   243 		} );
       
   244 
       
   245 		// Inject links for new elements added to the page.
       
   246 		if ( 'undefined' !== typeof MutationObserver ) {
       
   247 			api.mutationObserver = new MutationObserver( function( mutations ) {
       
   248 				_.each( mutations, function( mutation ) {
       
   249 					$( mutation.target ).find( linkSelectors ).each( function() {
       
   250 						api.prepareLinkPreview( this );
       
   251 					} );
       
   252 				} );
       
   253 			} );
       
   254 			api.mutationObserver.observe( document.documentElement, {
       
   255 				childList: true,
       
   256 				subtree: true
       
   257 			} );
       
   258 		} else {
       
   259 
       
   260 			// If mutation observers aren't available, fallback to just-in-time injection.
       
   261 			$( document.documentElement ).on( 'click focus mouseover', linkSelectors, function() {
       
   262 				api.prepareLinkPreview( this );
       
   263 			} );
       
   264 		}
       
   265 	};
       
   266 
       
   267 	/**
       
   268 	 * Should the supplied link is previewable.
       
   269 	 *
       
   270 	 * @since 4.7.0
       
   271 	 * @access public
       
   272 	 *
       
   273 	 * @param {HTMLAnchorElement|HTMLAreaElement} element Link element.
       
   274 	 * @param {string} element.search Query string.
       
   275 	 * @param {string} element.pathname Path.
       
   276 	 * @param {string} element.host Host.
       
   277 	 * @param {object} [options]
       
   278 	 * @param {object} [options.allowAdminAjax=false] Allow admin-ajax.php requests.
       
   279 	 * @returns {boolean} Is appropriate for changeset link.
       
   280 	 */
       
   281 	api.isLinkPreviewable = function isLinkPreviewable( element, options ) {
       
   282 		var matchesAllowedUrl, parsedAllowedUrl, args, elementHost;
       
   283 
       
   284 		args = _.extend( {}, { allowAdminAjax: false }, options || {} );
       
   285 
       
   286 		if ( 'javascript:' === element.protocol ) { // jshint ignore:line
       
   287 			return true;
       
   288 		}
       
   289 
       
   290 		// Only web URLs can be previewed.
       
   291 		if ( 'https:' !== element.protocol && 'http:' !== element.protocol ) {
       
   292 			return false;
       
   293 		}
       
   294 
       
   295 		elementHost = element.host.replace( /:(80|443)$/, '' );
       
   296 		parsedAllowedUrl = document.createElement( 'a' );
       
   297 		matchesAllowedUrl = ! _.isUndefined( _.find( api.settings.url.allowed, function( allowedUrl ) {
       
   298 			parsedAllowedUrl.href = allowedUrl;
       
   299 			return parsedAllowedUrl.protocol === element.protocol && parsedAllowedUrl.host.replace( /:(80|443)$/, '' ) === elementHost && 0 === element.pathname.indexOf( parsedAllowedUrl.pathname.replace( /\/$/, '' ) );
       
   300 		} ) );
       
   301 		if ( ! matchesAllowedUrl ) {
       
   302 			return false;
       
   303 		}
       
   304 
       
   305 		// Skip wp login and signup pages.
       
   306 		if ( /\/wp-(login|signup)\.php$/.test( element.pathname ) ) {
       
   307 			return false;
       
   308 		}
       
   309 
       
   310 		// Allow links to admin ajax as faux frontend URLs.
       
   311 		if ( /\/wp-admin\/admin-ajax\.php$/.test( element.pathname ) ) {
       
   312 			return args.allowAdminAjax;
       
   313 		}
       
   314 
       
   315 		// Disallow links to admin, includes, and content.
       
   316 		if ( /\/wp-(admin|includes|content)(\/|$)/.test( element.pathname ) ) {
       
   317 			return false;
       
   318 		}
       
   319 
       
   320 		return true;
       
   321 	};
       
   322 
       
   323 	/**
       
   324 	 * Inject the customize_changeset_uuid query param into links on the frontend.
       
   325 	 *
       
   326 	 * @since 4.7.0
       
   327 	 * @access protected
       
   328 	 *
       
   329 	 * @param {HTMLAnchorElement|HTMLAreaElement} element Link element.
       
   330 	 * @param {string} element.search Query string.
       
   331 	 * @param {string} element.host Host.
       
   332 	 * @param {string} element.protocol Protocol.
       
   333 	 * @returns {void}
       
   334 	 */
       
   335 	api.prepareLinkPreview = function prepareLinkPreview( element ) {
       
   336 		var queryParams, $element = $( element );
       
   337 
       
   338 		// Skip links in admin bar.
       
   339 		if ( $element.closest( '#wpadminbar' ).length ) {
       
   340 			return;
       
   341 		}
       
   342 
       
   343 		// Ignore links with href="#", href="#id", or non-HTTP protocols (e.g. javascript: and mailto:).
       
   344 		if ( '#' === $element.attr( 'href' ).substr( 0, 1 ) || ! /^https?:$/.test( element.protocol ) ) {
       
   345 			return;
       
   346 		}
       
   347 
       
   348 		// Make sure links in preview use HTTPS if parent frame uses HTTPS.
       
   349 		if ( api.settings.channel && 'https' === api.preview.scheme.get() && 'http:' === element.protocol && -1 !== api.settings.url.allowedHosts.indexOf( element.host ) ) {
       
   350 			element.protocol = 'https:';
       
   351 		}
       
   352 
       
   353 		// Ignore links with class wp-playlist-caption
       
   354 		if ( $element.hasClass( 'wp-playlist-caption' ) ) {
       
   355 			return;
       
   356 		}
       
   357 
       
   358 		if ( ! api.isLinkPreviewable( element ) ) {
       
   359 
       
   360 			// Style link as unpreviewable only if previewing in iframe; if previewing on frontend, links will be allowed to work normally.
       
   361 			if ( api.settings.channel ) {
       
   362 				$element.addClass( 'customize-unpreviewable' );
       
   363 			}
       
   364 			return;
       
   365 		}
       
   366 		$element.removeClass( 'customize-unpreviewable' );
       
   367 
       
   368 		queryParams = api.utils.parseQueryString( element.search.substring( 1 ) );
       
   369 		queryParams.customize_changeset_uuid = api.settings.changeset.uuid;
       
   370 		if ( api.settings.changeset.autosaved ) {
       
   371 			queryParams.customize_autosaved = 'on';
       
   372 		}
       
   373 		if ( ! api.settings.theme.active ) {
       
   374 			queryParams.customize_theme = api.settings.theme.stylesheet;
       
   375 		}
       
   376 		if ( api.settings.channel ) {
       
   377 			queryParams.customize_messenger_channel = api.settings.channel;
       
   378 		}
       
   379 		element.search = $.param( queryParams );
       
   380 
       
   381 		// Prevent links from breaking out of preview iframe.
       
   382 		if ( api.settings.channel ) {
       
   383 			element.target = '_self';
       
   384 		}
       
   385 	};
       
   386 
       
   387 	/**
       
   388 	 * Inject the changeset UUID into Ajax requests.
       
   389 	 *
       
   390 	 * @since 4.7.0
       
   391 	 * @access protected
       
   392 	 *
       
   393 	 * @return {void}
       
   394 	 */
       
   395 	api.addRequestPreviewing = function addRequestPreviewing() {
       
   396 
       
   397 		/**
       
   398 		 * Rewrite Ajax requests to inject customizer state.
       
   399 		 *
       
   400 		 * @param {object} options Options.
       
   401 		 * @param {string} options.type Type.
       
   402 		 * @param {string} options.url URL.
       
   403 		 * @param {object} originalOptions Original options.
       
   404 		 * @param {XMLHttpRequest} xhr XHR.
       
   405 		 * @returns {void}
       
   406 		 */
       
   407 		var prefilterAjax = function( options, originalOptions, xhr ) {
       
   408 			var urlParser, queryParams, requestMethod, dirtyValues = {};
       
   409 			urlParser = document.createElement( 'a' );
       
   410 			urlParser.href = options.url;
       
   411 
       
   412 			// Abort if the request is not for this site.
       
   413 			if ( ! api.isLinkPreviewable( urlParser, { allowAdminAjax: true } ) ) {
       
   414 				return;
       
   415 			}
       
   416 			queryParams = api.utils.parseQueryString( urlParser.search.substring( 1 ) );
       
   417 
       
   418 			// Note that _dirty flag will be cleared with changeset updates.
       
   419 			api.each( function( setting ) {
       
   420 				if ( setting._dirty ) {
       
   421 					dirtyValues[ setting.id ] = setting.get();
       
   422 				}
       
   423 			} );
       
   424 
       
   425 			if ( ! _.isEmpty( dirtyValues ) ) {
       
   426 				requestMethod = options.type.toUpperCase();
       
   427 
       
   428 				// Override underlying request method to ensure unsaved changes to changeset can be included (force Backbone.emulateHTTP).
       
   429 				if ( 'POST' !== requestMethod ) {
       
   430 					xhr.setRequestHeader( 'X-HTTP-Method-Override', requestMethod );
       
   431 					queryParams._method = requestMethod;
       
   432 					options.type = 'POST';
       
   433 				}
       
   434 
       
   435 				// Amend the post data with the customized values.
       
   436 				if ( options.data ) {
       
   437 					options.data += '&';
       
   438 				} else {
       
   439 					options.data = '';
       
   440 				}
       
   441 				options.data += $.param( {
       
   442 					customized: JSON.stringify( dirtyValues )
       
   443 				} );
       
   444 			}
       
   445 
       
   446 			// Include customized state query params in URL.
       
   447 			queryParams.customize_changeset_uuid = api.settings.changeset.uuid;
       
   448 			if ( api.settings.changeset.autosaved ) {
       
   449 				queryParams.customize_autosaved = 'on';
       
   450 			}
       
   451 			if ( ! api.settings.theme.active ) {
       
   452 				queryParams.customize_theme = api.settings.theme.stylesheet;
       
   453 			}
       
   454 
       
   455 			// Ensure preview nonce is included with every customized request, to allow post data to be read.
       
   456 			queryParams.customize_preview_nonce = api.settings.nonce.preview;
       
   457 
       
   458 			urlParser.search = $.param( queryParams );
       
   459 			options.url = urlParser.href;
       
   460 		};
       
   461 
       
   462 		$.ajaxPrefilter( prefilterAjax );
       
   463 	};
       
   464 
       
   465 	/**
       
   466 	 * Inject changeset UUID into forms, allowing preview to persist through submissions.
       
   467 	 *
       
   468 	 * @since 4.7.0
       
   469 	 * @access protected
       
   470 	 *
       
   471 	 * @returns {void}
       
   472 	 */
       
   473 	api.addFormPreviewing = function addFormPreviewing() {
       
   474 
       
   475 		// Inject inputs for forms in initial document.
       
   476 		$( document.body ).find( 'form' ).each( function() {
       
   477 			api.prepareFormPreview( this );
       
   478 		} );
       
   479 
       
   480 		// Inject inputs for new forms added to the page.
       
   481 		if ( 'undefined' !== typeof MutationObserver ) {
       
   482 			api.mutationObserver = new MutationObserver( function( mutations ) {
       
   483 				_.each( mutations, function( mutation ) {
       
   484 					$( mutation.target ).find( 'form' ).each( function() {
       
   485 						api.prepareFormPreview( this );
       
   486 					} );
       
   487 				} );
       
   488 			} );
       
   489 			api.mutationObserver.observe( document.documentElement, {
       
   490 				childList: true,
       
   491 				subtree: true
       
   492 			} );
       
   493 		}
       
   494 	};
       
   495 
       
   496 	/**
       
   497 	 * Inject changeset into form inputs.
       
   498 	 *
       
   499 	 * @since 4.7.0
       
   500 	 * @access protected
       
   501 	 *
       
   502 	 * @param {HTMLFormElement} form Form.
       
   503 	 * @returns {void}
       
   504 	 */
       
   505 	api.prepareFormPreview = function prepareFormPreview( form ) {
       
   506 		var urlParser, stateParams = {};
       
   507 
       
   508 		if ( ! form.action ) {
       
   509 			form.action = location.href;
       
   510 		}
       
   511 
       
   512 		urlParser = document.createElement( 'a' );
       
   513 		urlParser.href = form.action;
       
   514 
       
   515 		// Make sure forms in preview use HTTPS if parent frame uses HTTPS.
       
   516 		if ( api.settings.channel && 'https' === api.preview.scheme.get() && 'http:' === urlParser.protocol && -1 !== api.settings.url.allowedHosts.indexOf( urlParser.host ) ) {
       
   517 			urlParser.protocol = 'https:';
       
   518 			form.action = urlParser.href;
       
   519 		}
       
   520 
       
   521 		if ( 'GET' !== form.method.toUpperCase() || ! api.isLinkPreviewable( urlParser ) ) {
       
   522 
       
   523 			// Style form as unpreviewable only if previewing in iframe; if previewing on frontend, all forms will be allowed to work normally.
       
   524 			if ( api.settings.channel ) {
       
   525 				$( form ).addClass( 'customize-unpreviewable' );
       
   526 			}
       
   527 			return;
       
   528 		}
       
   529 		$( form ).removeClass( 'customize-unpreviewable' );
       
   530 
       
   531 		stateParams.customize_changeset_uuid = api.settings.changeset.uuid;
       
   532 		if ( api.settings.changeset.autosaved ) {
       
   533 			stateParams.customize_autosaved = 'on';
       
   534 		}
       
   535 		if ( ! api.settings.theme.active ) {
       
   536 			stateParams.customize_theme = api.settings.theme.stylesheet;
       
   537 		}
       
   538 		if ( api.settings.channel ) {
       
   539 			stateParams.customize_messenger_channel = api.settings.channel;
       
   540 		}
       
   541 
       
   542 		_.each( stateParams, function( value, name ) {
       
   543 			var input = $( form ).find( 'input[name="' + name + '"]' );
       
   544 			if ( input.length ) {
       
   545 				input.val( value );
       
   546 			} else {
       
   547 				$( form ).prepend( $( '<input>', {
       
   548 					type: 'hidden',
       
   549 					name: name,
       
   550 					value: value
       
   551 				} ) );
       
   552 			}
       
   553 		} );
       
   554 
       
   555 		// Prevent links from breaking out of preview iframe.
       
   556 		if ( api.settings.channel ) {
       
   557 			form.target = '_self';
       
   558 		}
       
   559 	};
       
   560 
       
   561 	/**
       
   562 	 * Watch current URL and send keep-alive (heartbeat) messages to the parent.
       
   563 	 *
       
   564 	 * Keep the customizer pane notified that the preview is still alive
       
   565 	 * and that the user hasn't navigated to a non-customized URL.
       
   566 	 *
       
   567 	 * @since 4.7.0
       
   568 	 * @access protected
       
   569 	 */
       
   570 	api.keepAliveCurrentUrl = ( function() {
       
   571 		var previousPathName = location.pathname,
       
   572 			previousQueryString = location.search.substr( 1 ),
       
   573 			previousQueryParams = null,
       
   574 			stateQueryParams = [ 'customize_theme', 'customize_changeset_uuid', 'customize_messenger_channel', 'customize_autosaved' ];
       
   575 
       
   576 		return function keepAliveCurrentUrl() {
       
   577 			var urlParser, currentQueryParams;
       
   578 
       
   579 			// Short-circuit with keep-alive if previous URL is identical (as is normal case).
       
   580 			if ( previousQueryString === location.search.substr( 1 ) && previousPathName === location.pathname ) {
       
   581 				api.preview.send( 'keep-alive' );
       
   582 				return;
       
   583 			}
       
   584 
       
   585 			urlParser = document.createElement( 'a' );
       
   586 			if ( null === previousQueryParams ) {
       
   587 				urlParser.search = previousQueryString;
       
   588 				previousQueryParams = api.utils.parseQueryString( previousQueryString );
       
   589 				_.each( stateQueryParams, function( name ) {
       
   590 					delete previousQueryParams[ name ];
       
   591 				} );
       
   592 			}
       
   593 
       
   594 			// Determine if current URL minus customized state params and URL hash.
       
   595 			urlParser.href = location.href;
       
   596 			currentQueryParams = api.utils.parseQueryString( urlParser.search.substr( 1 ) );
       
   597 			_.each( stateQueryParams, function( name ) {
       
   598 				delete currentQueryParams[ name ];
       
   599 			} );
       
   600 
       
   601 			if ( previousPathName !== location.pathname || ! _.isEqual( previousQueryParams, currentQueryParams ) ) {
       
   602 				urlParser.search = $.param( currentQueryParams );
       
   603 				urlParser.hash = '';
       
   604 				api.settings.url.self = urlParser.href;
       
   605 				api.preview.send( 'ready', {
       
   606 					currentUrl: api.settings.url.self,
       
   607 					activePanels: api.settings.activePanels,
       
   608 					activeSections: api.settings.activeSections,
       
   609 					activeControls: api.settings.activeControls,
       
   610 					settingValidities: api.settings.settingValidities
       
   611 				} );
       
   612 			} else {
       
   613 				api.preview.send( 'keep-alive' );
       
   614 			}
       
   615 			previousQueryParams = currentQueryParams;
       
   616 			previousQueryString = location.search.substr( 1 );
       
   617 			previousPathName = location.pathname;
       
   618 		};
       
   619 	} )();
       
   620 
       
   621 	api.settingPreviewHandlers = {
       
   622 
       
   623 		/**
       
   624 		 * Preview changes to custom logo.
       
   625 		 *
       
   626 		 * @param {number} attachmentId Attachment ID for custom logo.
       
   627 		 * @returns {void}
       
   628 		 */
       
   629 		custom_logo: function( attachmentId ) {
       
   630 			$( 'body' ).toggleClass( 'wp-custom-logo', !! attachmentId );
       
   631 		},
       
   632 
       
   633 		/**
       
   634 		 * Preview changes to custom css.
       
   635 		 *
       
   636 		 * @param {string} value Custom CSS..
       
   637 		 * @returns {void}
       
   638 		 */
       
   639 		custom_css: function( value ) {
       
   640 			$( '#wp-custom-css' ).text( value );
       
   641 		},
       
   642 
       
   643 		/**
       
   644 		 * Preview changes to any of the background settings.
       
   645 		 *
       
   646 		 * @returns {void}
       
   647 		 */
       
   648 		background: function() {
       
   649 			var css = '', settings = {};
       
   650 
       
   651 			_.each( ['color', 'image', 'preset', 'position_x', 'position_y', 'size', 'repeat', 'attachment'], function( prop ) {
       
   652 				settings[ prop ] = api( 'background_' + prop );
       
   653 			} );
       
   654 
       
   655 			/*
       
   656 			 * The body will support custom backgrounds if either the color or image are set.
       
   657 			 *
       
   658 			 * See get_body_class() in /wp-includes/post-template.php
       
   659 			 */
       
   660 			$( document.body ).toggleClass( 'custom-background', !! ( settings.color() || settings.image() ) );
       
   661 
       
   662 			if ( settings.color() ) {
       
   663 				css += 'background-color: ' + settings.color() + ';';
       
   664 			}
       
   665 
       
   666 			if ( settings.image() ) {
       
   667 				css += 'background-image: url("' + settings.image() + '");';
       
   668 				css += 'background-size: ' + settings.size() + ';';
       
   669 				css += 'background-position: ' + settings.position_x() + ' ' + settings.position_y() + ';';
       
   670 				css += 'background-repeat: ' + settings.repeat() + ';';
       
   671 				css += 'background-attachment: ' + settings.attachment() + ';';
       
   672 			}
       
   673 
       
   674 			$( '#custom-background-css' ).text( 'body.custom-background { ' + css + ' }' );
       
   675 		}
       
   676 	};
       
   677 
    65 	$( function() {
   678 	$( function() {
       
   679 		var bg, setValue, handleUpdatedChangesetUuid;
       
   680 
    66 		api.settings = window._wpCustomizeSettings;
   681 		api.settings = window._wpCustomizeSettings;
    67 		if ( ! api.settings )
   682 		if ( ! api.settings ) {
    68 			return;
   683 			return;
    69 
   684 		}
    70 		var bg;
       
    71 
   685 
    72 		api.preview = new api.Preview({
   686 		api.preview = new api.Preview({
    73 			url: window.location.href,
   687 			url: window.location.href,
    74 			channel: api.settings.channel
   688 			channel: api.settings.channel
    75 		});
   689 		});
    76 
   690 
       
   691 		api.addLinkPreviewing();
       
   692 		api.addRequestPreviewing();
       
   693 		api.addFormPreviewing();
       
   694 
       
   695 		/**
       
   696 		 * Create/update a setting value.
       
   697 		 *
       
   698 		 * @param {string}  id            - Setting ID.
       
   699 		 * @param {*}       value         - Setting value.
       
   700 		 * @param {boolean} [createDirty] - Whether to create a setting as dirty. Defaults to false.
       
   701 		 */
       
   702 		setValue = function( id, value, createDirty ) {
       
   703 			var setting = api( id );
       
   704 			if ( setting ) {
       
   705 				setting.set( value );
       
   706 			} else {
       
   707 				createDirty = createDirty || false;
       
   708 				setting = api.create( id, value, {
       
   709 					id: id
       
   710 				} );
       
   711 
       
   712 				// Mark dynamically-created settings as dirty so they will get posted.
       
   713 				if ( createDirty ) {
       
   714 					setting._dirty = true;
       
   715 				}
       
   716 			}
       
   717 		};
       
   718 
    77 		api.preview.bind( 'settings', function( values ) {
   719 		api.preview.bind( 'settings', function( values ) {
    78 			$.each( values, function( id, value ) {
   720 			$.each( values, setValue );
    79 				if ( api.has( id ) )
       
    80 					api( id ).set( value );
       
    81 				else
       
    82 					api.create( id, value );
       
    83 			});
       
    84 		});
   721 		});
    85 
   722 
    86 		api.preview.trigger( 'settings', api.settings.values );
   723 		api.preview.trigger( 'settings', api.settings.values );
    87 
   724 
       
   725 		$.each( api.settings._dirty, function( i, id ) {
       
   726 			var setting = api( id );
       
   727 			if ( setting ) {
       
   728 				setting._dirty = true;
       
   729 			}
       
   730 		} );
       
   731 
    88 		api.preview.bind( 'setting', function( args ) {
   732 		api.preview.bind( 'setting', function( args ) {
    89 			var value;
   733 			var createDirty = true;
    90 
   734 			setValue.apply( null, args.concat( createDirty ) );
    91 			args = args.slice();
       
    92 
       
    93 			if ( value = api( args.shift() ) )
       
    94 				value.set.apply( value, args );
       
    95 		});
   735 		});
    96 
   736 
    97 		api.preview.bind( 'sync', function( events ) {
   737 		api.preview.bind( 'sync', function( events ) {
       
   738 
       
   739 			/*
       
   740 			 * Delete any settings that already exist locally which haven't been
       
   741 			 * modified in the controls while the preview was loading. This prevents
       
   742 			 * situations where the JS value being synced from the pane may differ
       
   743 			 * from the PHP-sanitized JS value in the preview which causes the
       
   744 			 * non-sanitized JS value to clobber the PHP-sanitized value. This
       
   745 			 * is particularly important for selective refresh partials that
       
   746 			 * have a fallback refresh behavior since infinite refreshing would
       
   747 			 * result.
       
   748 			 */
       
   749 			if ( events.settings && events['settings-modified-while-loading'] ) {
       
   750 				_.each( _.keys( events.settings ), function( syncedSettingId ) {
       
   751 					if ( api.has( syncedSettingId ) && ! events['settings-modified-while-loading'][ syncedSettingId ] ) {
       
   752 						delete events.settings[ syncedSettingId ];
       
   753 					}
       
   754 				} );
       
   755 			}
       
   756 
    98 			$.each( events, function( event, args ) {
   757 			$.each( events, function( event, args ) {
    99 				api.preview.trigger( event, args );
   758 				api.preview.trigger( event, args );
   100 			});
   759 			});
   101 			api.preview.send( 'synced' );
   760 			api.preview.send( 'synced' );
   102 		});
   761 		});
   103 
   762 
   104 		api.preview.bind( 'active', function() {
   763 		api.preview.bind( 'active', function() {
   105 			if ( api.settings.nonce ) {
   764 			api.preview.send( 'nonce', api.settings.nonce );
   106 				api.preview.send( 'nonce', api.settings.nonce );
       
   107 			}
       
   108 
   765 
   109 			api.preview.send( 'documentTitle', document.title );
   766 			api.preview.send( 'documentTitle', document.title );
       
   767 
       
   768 			// Send scroll in case of loading via non-refresh.
       
   769 			api.preview.send( 'scroll', $( window ).scrollTop() );
   110 		});
   770 		});
   111 
   771 
       
   772 		/**
       
   773 		 * Handle update to changeset UUID.
       
   774 		 *
       
   775 		 * @param {string} uuid - UUID.
       
   776 		 * @returns {void}
       
   777 		 */
       
   778 		handleUpdatedChangesetUuid = function( uuid ) {
       
   779 			api.settings.changeset.uuid = uuid;
       
   780 
       
   781 			// Update UUIDs in links and forms.
       
   782 			$( document.body ).find( 'a[href], area' ).each( function() {
       
   783 				api.prepareLinkPreview( this );
       
   784 			} );
       
   785 			$( document.body ).find( 'form' ).each( function() {
       
   786 				api.prepareFormPreview( this );
       
   787 			} );
       
   788 
       
   789 			/*
       
   790 			 * Replace the UUID in the URL. Note that the wrapped history.replaceState()
       
   791 			 * will handle injecting the current api.settings.changeset.uuid into the URL,
       
   792 			 * so this is merely to trigger that logic.
       
   793 			 */
       
   794 			if ( history.replaceState ) {
       
   795 				history.replaceState( currentHistoryState, '', location.href );
       
   796 			}
       
   797 		};
       
   798 
       
   799 		api.preview.bind( 'changeset-uuid', handleUpdatedChangesetUuid );
       
   800 
       
   801 		api.preview.bind( 'saved', function( response ) {
       
   802 			if ( response.next_changeset_uuid ) {
       
   803 				handleUpdatedChangesetUuid( response.next_changeset_uuid );
       
   804 			}
       
   805 			api.trigger( 'saved', response );
       
   806 		} );
       
   807 
       
   808 		// Update the URLs to reflect the fact we've started autosaving.
       
   809 		api.preview.bind( 'autosaving', function() {
       
   810 			if ( api.settings.changeset.autosaved ) {
       
   811 				return;
       
   812 			}
       
   813 
       
   814 			api.settings.changeset.autosaved = true; // Start deferring to any autosave once changeset is updated.
       
   815 
       
   816 			$( document.body ).find( 'a[href], area' ).each( function() {
       
   817 				api.prepareLinkPreview( this );
       
   818 			} );
       
   819 			$( document.body ).find( 'form' ).each( function() {
       
   820 				api.prepareFormPreview( this );
       
   821 			} );
       
   822 			if ( history.replaceState ) {
       
   823 				history.replaceState( currentHistoryState, '', location.href );
       
   824 			}
       
   825 		} );
       
   826 
       
   827 		/*
       
   828 		 * Clear dirty flag for settings when saved to changeset so that they
       
   829 		 * won't be needlessly included in selective refresh or ajax requests.
       
   830 		 */
       
   831 		api.preview.bind( 'changeset-saved', function( data ) {
       
   832 			_.each( data.saved_changeset_values, function( value, settingId ) {
       
   833 				var setting = api( settingId );
       
   834 				if ( setting && _.isEqual( setting.get(), value ) ) {
       
   835 					setting._dirty = false;
       
   836 				}
       
   837 			} );
       
   838 		} );
       
   839 
       
   840 		api.preview.bind( 'nonce-refresh', function( nonce ) {
       
   841 			$.extend( api.settings.nonce, nonce );
       
   842 		} );
       
   843 
       
   844 		/*
       
   845 		 * Send a message to the parent customize frame with a list of which
       
   846 		 * containers and controls are active.
       
   847 		 */
   112 		api.preview.send( 'ready', {
   848 		api.preview.send( 'ready', {
       
   849 			currentUrl: api.settings.url.self,
   113 			activePanels: api.settings.activePanels,
   850 			activePanels: api.settings.activePanels,
   114 			activeSections: api.settings.activeSections,
   851 			activeSections: api.settings.activeSections,
   115 			activeControls: api.settings.activeControls
   852 			activeControls: api.settings.activeControls,
   116 		} );
   853 			settingValidities: api.settings.settingValidities
       
   854 		} );
       
   855 
       
   856 		// Send ready when URL changes via JS.
       
   857 		setInterval( api.keepAliveCurrentUrl, api.settings.timeouts.keepAliveSend );
   117 
   858 
   118 		// Display a loading indicator when preview is reloading, and remove on failure.
   859 		// Display a loading indicator when preview is reloading, and remove on failure.
   119 		api.preview.bind( 'loading-initiated', function () {
   860 		api.preview.bind( 'loading-initiated', function () {
   120 			$( 'body' ).addClass( 'wp-customizer-unloading' );
   861 			$( 'body' ).addClass( 'wp-customizer-unloading' );
   121 			$( 'html' ).prop( 'title', api.settings.l10n.loading );
       
   122 		});
   862 		});
   123 		api.preview.bind( 'loading-failed', function () {
   863 		api.preview.bind( 'loading-failed', function () {
   124 			$( 'body' ).removeClass( 'wp-customizer-unloading' );
   864 			$( 'body' ).removeClass( 'wp-customizer-unloading' );
   125 			$( 'html' ).prop( 'title', '' );
       
   126 		});
   865 		});
   127 
   866 
   128 		/* Custom Backgrounds */
   867 		/* Custom Backgrounds */
   129 		bg = $.map(['color', 'image', 'position_x', 'repeat', 'attachment'], function( prop ) {
   868 		bg = $.map( ['color', 'image', 'preset', 'position_x', 'position_y', 'size', 'repeat', 'attachment'], function( prop ) {
   130 			return 'background_' + prop;
   869 			return 'background_' + prop;
   131 		});
   870 		} );
   132 
   871 
   133 		api.when.apply( api, bg ).done( function( color, image, position_x, repeat, attachment ) {
   872 		api.when.apply( api, bg ).done( function() {
   134 			var body = $(document.body),
       
   135 				head = $('head'),
       
   136 				style = $('#custom-background-css'),
       
   137 				update;
       
   138 
       
   139 			update = function() {
       
   140 				var css = '';
       
   141 
       
   142 				// The body will support custom backgrounds if either
       
   143 				// the color or image are set.
       
   144 				//
       
   145 				// See get_body_class() in /wp-includes/post-template.php
       
   146 				body.toggleClass( 'custom-background', !! ( color() || image() ) );
       
   147 
       
   148 				if ( color() )
       
   149 					css += 'background-color: ' + color() + ';';
       
   150 
       
   151 				if ( image() ) {
       
   152 					css += 'background-image: url("' + image() + '");';
       
   153 					css += 'background-position: top ' + position_x() + ';';
       
   154 					css += 'background-repeat: ' + repeat() + ';';
       
   155 					css += 'background-attachment: ' + attachment() + ';';
       
   156 				}
       
   157 
       
   158 				// Refresh the stylesheet by removing and recreating it.
       
   159 				style.remove();
       
   160 				style = $('<style type="text/css" id="custom-background-css">body.custom-background { ' + css + ' }</style>').appendTo( head );
       
   161 			};
       
   162 
       
   163 			$.each( arguments, function() {
   873 			$.each( arguments, function() {
   164 				this.bind( update );
   874 				this.bind( api.settingPreviewHandlers.background );
   165 			});
   875 			});
   166 		});
   876 		});
   167 
   877 
       
   878 		/**
       
   879 		 * Custom Logo
       
   880 		 *
       
   881 		 * Toggle the wp-custom-logo body class when a logo is added or removed.
       
   882 		 *
       
   883 		 * @since 4.5.0
       
   884 		 */
       
   885 		api( 'custom_logo', function ( setting ) {
       
   886 			api.settingPreviewHandlers.custom_logo.call( setting, setting.get() );
       
   887 			setting.bind( api.settingPreviewHandlers.custom_logo );
       
   888 		} );
       
   889 
       
   890 		api( 'custom_css[' + api.settings.theme.stylesheet + ']', function( setting ) {
       
   891 			setting.bind( api.settingPreviewHandlers.custom_css );
       
   892 		} );
       
   893 
   168 		api.trigger( 'preview-ready' );
   894 		api.trigger( 'preview-ready' );
   169 	});
   895 	});
   170 
   896 
   171 })( wp, jQuery );
   897 })( wp, jQuery );