WordPress/wp-includes/js/media-editor.js

/* global getUserSetting, tinymce, QTags, wpActiveEditor */

// WordPress, TinyMCE, and Media
// -----------------------------
(function($){
	/**
	 * Stores the editors' `wp.media.controller.Frame` instances.
	 *
	 * @static
	 */
	var workflows = {}, cache = {};

	/**
	 * wp.media.string
	 * @namespace
	 */
	wp.media.string = {
		/**
		 * Joins the `props` and `attachment` objects,
		 * outputting the proper object format based on the
		 * attachment's type.
		 *
		 * @global wp.media.view.settings
		 * @global getUserSetting()
		 *
		 * @param {Object} [props={}] Attachment details (align, link, size, etc).
		 * @param {Object} attachment The attachment object, media version of Post.
		 * @returns {Object} Joined props
		 */
		props: function( props, attachment ) {
			var link, linkUrl, size, sizes, fallbacks,
				defaultProps = wp.media.view.settings.defaultProps;

			// Final fallbacks run after all processing has been completed.
			fallbacks = function( props ) {
				// Generate alt fallbacks and strip tags.
				if ( 'image' === props.type && ! props.alt ) {
					props.alt = props.caption || props.title || '';
					props.alt = props.alt.replace( /<\/?[^>]+>/g, '' );
					props.alt = props.alt.replace( /[\r\n]+/g, ' ' );
				}

				return props;
			};

			props = props ? _.clone( props ) : {};

			if ( attachment && attachment.type ) {
				props.type = attachment.type;
			}

			if ( 'image' === props.type ) {
				props = _.defaults( props || {}, {
					align:   defaultProps.align || getUserSetting( 'align', 'none' ),
					size:    defaultProps.size  || getUserSetting( 'imgsize', 'medium' ),
					url:     '',
					classes: []
				});
			}

			// All attachment-specific settings follow.
			if ( ! attachment ) {
				return fallbacks( props );
			}

			props.title = props.title || attachment.title;

			link = props.link || defaultProps.link || getUserSetting( 'urlbutton', 'file' );
			if ( 'file' === link || 'embed' === link ) {
				linkUrl = attachment.url;
			} else if ( 'post' === link ) {
				linkUrl = attachment.link;
			} else if ( 'custom' === link ) {
				linkUrl = props.linkUrl;
			}
			props.linkUrl = linkUrl || '';

			// Format properties for images.
			if ( 'image' === attachment.type ) {
				props.classes.push( 'wp-image-' + attachment.id );

				sizes = attachment.sizes;
				size = sizes && sizes[ props.size ] ? sizes[ props.size ] : attachment;

				_.extend( props, _.pick( attachment, 'align', 'caption', 'alt' ), {
					width:     size.width,
					height:    size.height,
					src:       size.url,
					captionId: 'attachment_' + attachment.id
				});
			} else if ( 'video' === attachment.type || 'audio' === attachment.type ) {
				_.extend( props, _.pick( attachment, 'title', 'type', 'icon', 'mime' ) );
			// Format properties for non-images.
			} else {
				props.title = props.title || attachment.filename;
				props.rel = props.rel || 'attachment wp-att-' + attachment.id;
			}

			return fallbacks( props );
		},
		/**
		 * Create link markup that is suitable for passing to the editor
		 *
		 * @global wp.html.string
		 *
		 * @param {Object} props Attachment details (align, link, size, etc).
		 * @param {Object} attachment The attachment object, media version of Post.
		 * @returns {string} The link markup
		 */
		link: function( props, attachment ) {
			var options;

			props = wp.media.string.props( props, attachment );

			options = {
				tag:     'a',
				content: props.title,
				attrs:   {
					href: props.linkUrl
				}
			};

			if ( props.rel ) {
				options.attrs.rel = props.rel;
			}

			return wp.html.string( options );
		},
		/**
		 * Create an Audio shortcode string that is suitable for passing to the editor
		 *
		 * @param {Object} props Attachment details (align, link, size, etc).
		 * @param {Object} attachment The attachment object, media version of Post.
		 * @returns {string} The audio shortcode
		 */
		audio: function( props, attachment ) {
			return wp.media.string._audioVideo( 'audio', props, attachment );
		},
		/**
		 * Create a Video shortcode string that is suitable for passing to the editor
		 *
		 * @param {Object} props Attachment details (align, link, size, etc).
		 * @param {Object} attachment The attachment object, media version of Post.
		 * @returns {string} The video shortcode
		 */
		video: function( props, attachment ) {
			return wp.media.string._audioVideo( 'video', props, attachment );
		},
		/**
		 * Helper function to create a media shortcode string
		 *
		 * @access private
		 *
		 * @global wp.shortcode
		 * @global wp.media.view.settings
		 *
		 * @param {string} type The shortcode tag name: 'audio' or 'video'.
		 * @param {Object} props Attachment details (align, link, size, etc).
		 * @param {Object} attachment The attachment object, media version of Post.
		 * @returns {string} The media shortcode
		 */
		_audioVideo: function( type, props, attachment ) {
			var shortcode, html, extension;

			props = wp.media.string.props( props, attachment );
			if ( props.link !== 'embed' )
				return wp.media.string.link( props );

			shortcode = {};

			if ( 'video' === type ) {
				if ( attachment.width ) {
					shortcode.width = attachment.width;
				}

				if ( attachment.height ) {
					shortcode.height = attachment.height;
				}
			}

			extension = attachment.filename.split('.').pop();

			if ( _.contains( wp.media.view.settings.embedExts, extension ) ) {
				shortcode[extension] = attachment.url;
			} else {
				// Render unsupported audio and video files as links.
				return wp.media.string.link( props );
			}

			html = wp.shortcode.string({
				tag:     type,
				attrs:   shortcode
			});

			return html;
		},
		/**
		 * Create image markup, optionally with a link and/or wrapped in a caption shortcode,
		 *  that is suitable for passing to the editor
		 *
		 * @global wp.html
		 * @global wp.shortcode
		 *
		 * @param {Object} props Attachment details (align, link, size, etc).
		 * @param {Object} attachment The attachment object, media version of Post.
		 * @returns {string}
		 */
		image: function( props, attachment ) {
			var img = {},
				options, classes, shortcode, html;

			props = wp.media.string.props( props, attachment );
			classes = props.classes || [];

			img.src = typeof attachment !== 'undefined' ? attachment.url : props.url;
			_.extend( img, _.pick( props, 'width', 'height', 'alt' ) );

			// Only assign the align class to the image if we're not printing
			// a caption, since the alignment is sent to the shortcode.
			if ( props.align && ! props.caption ) {
				classes.push( 'align' + props.align );
			}

			if ( props.size ) {
				classes.push( 'size-' + props.size );
			}

			img['class'] = _.compact( classes ).join(' ');

			// Generate `img` tag options.
			options = {
				tag:    'img',
				attrs:  img,
				single: true
			};

			// Generate the `a` element options, if they exist.
			if ( props.linkUrl ) {
				options = {
					tag:   'a',
					attrs: {
						href: props.linkUrl
					},
					content: options
				};
			}

			html = wp.html.string( options );

			// Generate the caption shortcode.
			if ( props.caption ) {
				shortcode = {};

				if ( img.width ) {
					shortcode.width = img.width;
				}

				if ( props.captionId ) {
					shortcode.id = props.captionId;
				}

				if ( props.align ) {
					shortcode.align = 'align' + props.align;
				}

				html = wp.shortcode.string({
					tag:     'caption',
					attrs:   shortcode,
					content: html + ' ' + props.caption
				});
			}

			return html;
		}
	};

	/**
	 * wp.media.collection
	 * @namespace
	 */
	wp.media.collection = {
		attachments : function ( prop, type ) {
			/**
			 * Retrieve attachments based on the properties of the passed shortcode
			 *
			 * @global wp.media.query
			 *
			 * @param {wp.shortcode} shortcode An instance of wp.shortcode().
			 * @returns {wp.media.model.Attachments} A Backbone.Collection containing
			 *      the media items belonging to a collection.
			 *      The 'prop' specified by the passed prop is a Backbone.Model
			 *			containing the 'props' for the gallery.
			 */
			return function( shortcode ) {
				var shortcodeString = shortcode.string(),
					result = cache[ shortcodeString ],
					attrs, args, query, others;

				delete cache[ shortcodeString ];

				if ( result ) {
					return result;
				}

				// Fill the default shortcode attributes.
				attrs = _.defaults( shortcode.attrs.named, this.defaults );
				args  = _.pick( attrs, 'orderby', 'order' );

				args.type = type;
				args.perPage = -1;

				// Mark the `orderby` override attribute.
				if ( undefined !== attrs.orderby ) {
					attrs._orderByField = attrs.orderby;
				}

				if ( 'rand' === attrs.orderby ) {
					attrs._orderbyRandom = true;
				}

				if ( -1 !== jQuery.inArray( prop, ['playlist', 'video-playlist'] ) ) {
					_.each(['tracknumbers', 'tracklist', 'images', 'artists'], function (setting) {
						if ( 'undefined' === typeof attrs[setting] ) {
							attrs['_' + setting] = wp.media[ prop ].defaults[ setting ];
						} else if ( 'true' === attrs[setting] || true === attrs[setting] ) {
							attrs['_' + setting] = true;
						}
					});
				}

				// Map the `orderby` attribute to the corresponding model property.
				if ( ! attrs.orderby || /^menu_order(?: ID)?$/i.test( attrs.orderby ) ) {
					args.orderby = 'menuOrder';
				}

				// Map the `ids` param to the correct query args.
				if ( attrs.ids ) {
					args.post__in = attrs.ids.split(',');
					args.orderby  = 'post__in';
				} else if ( attrs.include ) {
					args.post__in = attrs.include.split(',');
				}

				if ( attrs.exclude ) {
					args.post__not_in = attrs.exclude.split(',');
				}

				if ( ! args.post__in ) {
					args.uploadedTo = attrs.id;
				}

				// Collect the attributes that were not included in `args`.
				others = _.omit( attrs, 'id', 'ids', 'include', 'exclude', 'orderby', 'order' );

				query = wp.media.query( args );
				query[ prop ] = new Backbone.Model( others );
				return query;
			};
		},

		shortcodeAttrs : function ( prop, attachments ) {
			var props = attachments.props.toJSON(),
				attrs = _.pick( props, 'orderby', 'order', 'style' );

			if ( attachments[ prop ] ) {
				_.extend( attrs, attachments[ prop ].toJSON() );
			}

			// Convert all collection shortcodes to use the `ids` property.
			// Ignore `post__in` and `post__not_in`; the attachments in
			// the collection will already reflect those properties.
			attrs.ids = attachments.pluck('id');

			// Copy the `uploadedTo` post ID.
			if ( props.uploadedTo ) {
				attrs.id = props.uploadedTo;
			}

			// Check if the collection is randomly ordered.
			delete attrs.orderby;

			if ( attrs._orderbyRandom ) {
				attrs.orderby = 'rand';
			} else if ( attrs._orderByField && attrs._orderByField != 'rand' ) {
				attrs.orderby = attrs._orderByField;
			}

			delete attrs._orderbyRandom;
			delete attrs._orderByField;

			// If the `ids` attribute is set and `orderby` attribute
			// is the default value, clear it for cleaner output.
			if ( attrs.ids && 'post__in' === attrs.orderby ) {
				delete attrs.orderby;
			}

			if ( -1 !== jQuery.inArray( prop, ['playlist', 'video-playlist'] ) ) {
				_.each(['tracknumbers', 'tracklist', 'images', 'artists'], function (setting) {
					if ( 'undefined' === typeof attrs[ '_' + setting ] ) {
						attrs[ '_' + setting ] = wp.media[ prop ].defaults[ setting ];
					}

					if ( attrs['_' + setting] ) {
						attrs[setting] = true;
					} else {
						attrs[setting] = false;
					}
					delete attrs['_' + setting];
				});
			}

			// Remove default attributes from the shortcode.
			_.each( wp.media[prop].defaults, function( value, key ) {
				if ( value === attrs[ key ] ) {
					delete attrs[ key ];
				}
			});
			return attrs;
		},

		editSelection : function ( prop, shortcode ) {
			var defaultPostId = wp.media[ prop ].defaults.id,
				attachments, selection;

			// Ignore the rest of the match object.
			shortcode = shortcode.shortcode;

			if ( _.isUndefined( shortcode.get('id') ) && ! _.isUndefined( defaultPostId ) ) {
				shortcode.set( 'id', defaultPostId );
			}

			attachments = wp.media[ prop ].attachments( shortcode );

			selection = new wp.media.model.Selection( attachments.models, {
				props:    attachments.props.toJSON(),
				multiple: true
			});

			selection[ prop ] = attachments[ prop ];

			// Fetch the query's attachments, and then break ties from the
			// query to allow for sorting.
			selection.more().done( function() {
				// Break ties with the query.
				selection.props.set({ query: false });
				selection.unmirror();
				selection.props.unset('orderby');
			});

			return selection;
		},

		/**
		 *
		 * @param {string} prop The shortcode slug
		 * @param {wp.media.model.Attachments} attachments
		 * @param {wp.shortcode} shortcode
		 * @returns {wp.shortcode}
		 */
		cacheShortcode : function ( prop, attachments, shortcode ) {
			// Use a cloned version of the playlist.
			var clone = new wp.media.model.Attachments( attachments.models, {
				props: attachments.props.toJSON()
			});
			clone[ prop ] = attachments[ prop ];
			cache[ shortcode.string() ] = clone;

			return shortcode;
		},

		getEditFrame : function ( args ) {
			// Destroy the previous gallery frame.
			if ( this.frame ) {
				this.frame.dispose();
			}

			// Store the current gallery frame.
			this.frame = wp.media( _.extend( {
				frame:     'post',
				editing:   true,
				multiple:  true
			}, args ) ).open();

			return this.frame;
		},

		instance : function ( prop, args ) {
			return {
				attachments: this.attachments( prop, args.type ),
				/**
				 * Triggered when clicking 'Insert {label}' or 'Update {label}'
				 *
				 * @global wp.shortcode
				 * @global wp.media.model.Attachments
				 *
				 * @param {wp.media.model.Attachments} attachments A Backbone.Collection containing
				 *      the media items belonging to a collection.
				 *      The 'prop' specified by the passed prop is a Backbone.Model
				 *			containing the 'props' for the gallery.
				 * @returns {wp.shortcode}
				 */
				shortcode: function( attachments ) {
					var shortcode = new wp.shortcode({
						tag: prop,
						attrs: wp.media.collection.shortcodeAttrs( prop, attachments ),
						type: 'single'
					});

					return wp.media.collection.cacheShortcode( prop, attachments, shortcode );
				},
				/**
				 * Triggered when double-clicking a collection shortcode placeholder
				 *   in the editor
				 *
				 * @global wp.shortcode
				 * @global wp.media.model.Selection
				 * @global wp.media.view.l10n
				 *
				 * @param {string} content Content that is searched for possible
				 *    shortcode markup matching the passed tag name,
				 *
				 * @this wp.media.{prop}
				 *
				 * @returns {wp.media.view.MediaFrame.Select} A media workflow.
				 */
				edit: function( content ) {
					var shortcode = wp.shortcode.next( prop, content );

					// Bail if we didn't match the shortcode or all of the content.
					if ( ! shortcode || shortcode.content !== content ) {
						return;
					}

					return wp.media.collection.getEditFrame( {
						title: args.title,
						state: prop + '-edit',
						selection:	wp.media.collection.editSelection( prop, shortcode )
					} );
				}
			};
		}
	};

	wp.media.gallery = (function() {
		var gallery = {
			defaults : {
				itemtag: 'dl',
				icontag: 'dt',
				captiontag: 'dd',
				columns: '3',
				link: 'post',
				size: 'thumbnail',
				order: 'ASC',
				id: wp.media.view.settings.post.id,
				orderby : 'menu_order ID'
			}
		};

		return _.extend(gallery, wp.media.collection.instance( 'gallery', {
			type : 'image',
			title : wp.media.view.l10n.editGalleryTitle
		}));
	}());

	wp.media.playlist = (function() {
		var playlist = {
			defaults : {
				id: wp.media.view.settings.post.id,
				style: 'light',
				tracklist: true,
				tracknumbers: true,
				images: true,
				artists: true
			}
		};

		return _.extend(playlist, wp.media.collection.instance( 'playlist', {
			type : 'audio',
			title : wp.media.view.l10n.editPlaylistTitle
		}));
	}());

	wp.media['video-playlist'] = (function() {
		var playlist = {
			defaults : {
				id: wp.media.view.settings.post.id,
				style: 'light',
				tracklist: false,
				tracknumbers: false,
				images: true
			}
		};

		return _.extend(playlist, wp.media.collection.instance( 'video-playlist', {
			type : 'video',
			title : wp.media.view.l10n.editVideoPlaylistTitle
		}));
	}());

	/**
	 * wp.media.featuredImage
	 * @namespace
	 */
	wp.media.featuredImage = {
		/**
		 * Get the featured image post ID
		 *
		 * @global wp.media.view.settings
		 *
		 * @returns {wp.media.view.settings.post.featuredImageId|number}
		 */
		get: function() {
			return wp.media.view.settings.post.featuredImageId;
		},
		/**
		 * Set the featured image id, save the post thumbnail data and
		 * set the HTML in the post meta box to the new featured image.
		 *
		 * @global wp.media.view.settings
		 * @global wp.media.post
		 *
		 * @param {number} id The post ID of the featured image, or -1 to unset it.
		 */
		set: function( id ) {
			var settings = wp.media.view.settings;

			settings.post.featuredImageId = id;

			wp.media.post( 'set-post-thumbnail', {
				json:         true,
				post_id:      settings.post.id,
				thumbnail_id: settings.post.featuredImageId,
				_wpnonce:     settings.post.nonce
			}).done( function( html ) {
				$( '.inside', '#postimagediv' ).html( html );
			});
		},
		/**
		 * The Featured Image workflow
		 *
		 * @global wp.media.controller.FeaturedImage
		 * @global wp.media.view.l10n
		 *
		 * @this wp.media.featuredImage
		 *
		 * @returns {wp.media.view.MediaFrame.Select} A media workflow.
		 */
		frame: function() {
			if ( this._frame ) {
				return this._frame;
			}

			this._frame = wp.media({
				state: 'featured-image',
				states: [ new wp.media.controller.FeaturedImage() ]
			});

			this._frame.on( 'toolbar:create:featured-image', function( toolbar ) {
				/**
				 * @this wp.media.view.MediaFrame.Select
				 */
				this.createSelectToolbar( toolbar, {
					text: wp.media.view.l10n.setFeaturedImage
				});
			}, this._frame );

			this._frame.state('featured-image').on( 'select', this.select );
			return this._frame;
		},
		/**
		 * 'select' callback for Featured Image workflow, triggered when
		 *  the 'Set Featured Image' button is clicked in the media modal.
		 *
		 * @global wp.media.view.settings
		 *
		 * @this wp.media.controller.FeaturedImage
		 */
		select: function() {
			var selection = this.get('selection').single();

			if ( ! wp.media.view.settings.post.featuredImageId ) {
				return;
			}

			wp.media.featuredImage.set( selection ? selection.id : -1 );
		},
		/**
		 * Open the content media manager to the 'featured image' tab when
		 * the post thumbnail is clicked.
		 *
		 * Update the featured image id when the 'remove' link is clicked.
		 *
		 * @global wp.media.view.settings
		 */
		init: function() {
			$('#postimagediv').on( 'click', '#set-post-thumbnail', function( event ) {
				event.preventDefault();
				// Stop propagation to prevent thickbox from activating.
				event.stopPropagation();

				wp.media.featuredImage.frame().open();
			}).on( 'click', '#remove-post-thumbnail', function() {
				wp.media.view.settings.post.featuredImageId = -1;
			});
		}
	};

	$( wp.media.featuredImage.init );

	/**
	 * wp.media.editor
	 * @namespace
	 */
	wp.media.editor = {
		/**
		 * Send content to the editor
		 *
		 * @global tinymce
		 * @global QTags
		 * @global wpActiveEditor
		 * @global tb_remove() - Possibly overloaded by legacy plugins
		 *
		 * @param {string} html Content to send to the editor
		 */
		insert: function( html ) {
			var editor,
				hasTinymce = typeof tinymce !== 'undefined',
				hasQuicktags = typeof QTags !== 'undefined',
				wpActiveEditor = window.wpActiveEditor;

			// Delegate to the global `send_to_editor` if it exists.
			// This attempts to play nice with any themes/plugins that have
			// overridden the insert functionality.
			if ( window.send_to_editor ) {
				return window.send_to_editor.apply( this, arguments );
			}

			if ( ! wpActiveEditor ) {
				if ( hasTinymce && tinymce.activeEditor ) {
					editor = tinymce.activeEditor;
					wpActiveEditor = window.wpActiveEditor = editor.id;
				} else if ( ! hasQuicktags ) {
					return false;
				}
			} else if ( hasTinymce ) {
				editor = tinymce.get( wpActiveEditor );
			}

			if ( editor && ! editor.isHidden() ) {
				editor.execCommand( 'mceInsertContent', false, html );
			} else if ( hasQuicktags ) {
				QTags.insertContent( html );
			} else {
				document.getElementById( wpActiveEditor ).value += html;
			}

			// If the old thickbox remove function exists, call it in case
			// a theme/plugin overloaded it.
			if ( window.tb_remove ) {
				try { window.tb_remove(); } catch( e ) {}
			}
		},

		/**
		 * Setup 'workflow' and add to the 'workflows' cache. 'open' can
		 *  subsequently be called upon it.
		 *
		 * @global wp.media.view.l10n
		 *
		 * @param {string} id A slug used to identify the workflow.
		 * @param {Object} [options={}]
		 *
		 * @this wp.media.editor
		 *
		 * @returns {wp.media.view.MediaFrame.Select} A media workflow.
		 */
		add: function( id, options ) {
			var workflow = this.get( id );

			// only add once: if exists return existing
			if ( workflow ) {
				return workflow;
			}

			workflow = workflows[ id ] = wp.media( _.defaults( options || {}, {
				frame:    'post',
				state:    'insert',
				title:    wp.media.view.l10n.addMedia,
				multiple: true
			} ) );

			workflow.on( 'insert', function( selection ) {
				var state = workflow.state();

				selection = selection || state.get('selection');

				if ( ! selection )
					return;

				$.when.apply( $, selection.map( function( attachment ) {
					var display = state.display( attachment ).toJSON();
					/**
					 * @this wp.media.editor
					 */
					return this.send.attachment( display, attachment.toJSON() );
				}, this ) ).done( function() {
					wp.media.editor.insert( _.toArray( arguments ).join('\n\n') );
				});
			}, this );

			workflow.state('gallery-edit').on( 'update', function( selection ) {
				/**
				 * @this wp.media.editor
				 */
				this.insert( wp.media.gallery.shortcode( selection ).string() );
			}, this );

			workflow.state('playlist-edit').on( 'update', function( selection ) {
				/**
				 * @this wp.media.editor
				 */
				this.insert( wp.media.playlist.shortcode( selection ).string() );
			}, this );

			workflow.state('video-playlist-edit').on( 'update', function( selection ) {
				/**
				 * @this wp.media.editor
				 */
				this.insert( wp.media['video-playlist'].shortcode( selection ).string() );
			}, this );

			workflow.state('embed').on( 'select', function() {
				/**
				 * @this wp.media.editor
				 */
				var state = workflow.state(),
					type = state.get('type'),
					embed = state.props.toJSON();

				embed.url = embed.url || '';

				if ( 'link' === type ) {
					_.defaults( embed, {
						title:   embed.url,
						linkUrl: embed.url
					});

					this.send.link( embed ).done( function( resp ) {
						wp.media.editor.insert( resp );
					});

				} else if ( 'image' === type ) {
					_.defaults( embed, {
						title:   embed.url,
						linkUrl: '',
						align:   'none',
						link:    'none'
					});

					if ( 'none' === embed.link ) {
						embed.linkUrl = '';
					} else if ( 'file' === embed.link ) {
						embed.linkUrl = embed.url;
					}

					this.insert( wp.media.string.image( embed ) );
				}
			}, this );

			workflow.state('featured-image').on( 'select', wp.media.featuredImage.select );
			workflow.setState( workflow.options.state );
			return workflow;
		},
		/**
		 * Determines the proper current workflow id
		 *
		 * @global wpActiveEditor
		 * @global tinymce
		 *
		 * @param {string} [id=''] A slug used to identify the workflow.
		 *
		 * @returns {wpActiveEditor|string|tinymce.activeEditor.id}
		 */
		id: function( id ) {
			if ( id ) {
				return id;
			}

			// If an empty `id` is provided, default to `wpActiveEditor`.
			id = wpActiveEditor;

			// If that doesn't work, fall back to `tinymce.activeEditor.id`.
			if ( ! id && typeof tinymce !== 'undefined' && tinymce.activeEditor ) {
				id = tinymce.activeEditor.id;
			}

			// Last but not least, fall back to the empty string.
			id = id || '';
			return id;
		},
		/**
		 * Return the workflow specified by id
		 *
		 * @param {string} id A slug used to identify the workflow.
		 *
		 * @this wp.media.editor
		 *
		 * @returns {wp.media.view.MediaFrame} A media workflow.
		 */
		get: function( id ) {
			id = this.id( id );
			return workflows[ id ];
		},
		/**
		 * Remove the workflow represented by id from the workflow cache
		 *
		 * @param {string} id A slug used to identify the workflow.
		 *
		 * @this wp.media.editor
		 */
		remove: function( id ) {
			id = this.id( id );
			delete workflows[ id ];
		},
		/**
		 * @namespace
		 */
		send: {
			/**
			 * Called when sending an attachment to the editor
			 *   from the medial modal.
			 *
			 * @global wp.media.view.settings
			 * @global wp.media.post
			 *
			 * @param {Object} props Attachment details (align, link, size, etc).
			 * @param {Object} attachment The attachment object, media version of Post.
			 * @returns {Promise}
			 */
			attachment: function( props, attachment ) {
				var caption = attachment.caption,
					options, html;

				// If captions are disabled, clear the caption.
				if ( ! wp.media.view.settings.captions ) {
					delete attachment.caption;
				}

				props = wp.media.string.props( props, attachment );

				options = {
					id:           attachment.id,
					post_content: attachment.description,
					post_excerpt: caption
				};

				if ( props.linkUrl ) {
					options.url = props.linkUrl;
				}

				if ( 'image' === attachment.type ) {
					html = wp.media.string.image( props );

					_.each({
						align: 'align',
						size:  'image-size',
						alt:   'image_alt'
					}, function( option, prop ) {
						if ( props[ prop ] )
							options[ option ] = props[ prop ];
					});
				} else if ( 'video' === attachment.type ) {
					html = wp.media.string.video( props, attachment );
				} else if ( 'audio' === attachment.type ) {
					html = wp.media.string.audio( props, attachment );
				} else {
					html = wp.media.string.link( props );
					options.post_title = props.title;
				}

				return wp.media.post( 'send-attachment-to-editor', {
					nonce:      wp.media.view.settings.nonce.sendToEditor,
					attachment: options,
					html:       html,
					post_id:    wp.media.view.settings.post.id
				});
			},
			/**
			 * Called when 'Insert From URL' source is not an image. Example: YouTube url.
			 *
			 * @global wp.media.view.settings
			 *
			 * @param {Object} embed
			 * @returns {Promise}
			 */
			link: function( embed ) {
				return wp.media.post( 'send-link-to-editor', {
					nonce:   wp.media.view.settings.nonce.sendToEditor,
					src:     embed.linkUrl,
					title:   embed.title,
					html:    wp.media.string.link( embed ),
					post_id: wp.media.view.settings.post.id
				});
			}
		},
		/**
		 * Open a workflow
		 *
		 * @param {string} [id=undefined] Optional. A slug used to identify the workflow.
		 * @param {Object} [options={}]
		 *
		 * @this wp.media.editor
		 *
		 * @returns {wp.media.view.MediaFrame}
		 */
		open: function( id, options ) {
			var workflow;

			options = options || {};

			id = this.id( id );
/*
			// Save a bookmark of the caret position in IE.
			if ( typeof tinymce !== 'undefined' ) {
				editor = tinymce.get( id );

				if ( tinymce.isIE && editor && ! editor.isHidden() ) {
					editor.focus();
					editor.windowManager.insertimagebookmark = editor.selection.getBookmark();
				}
			}
*/
			workflow = this.get( id );

			// Redo workflow if state has changed
			if ( ! workflow || ( workflow.options && options.state !== workflow.options.state ) ) {
				workflow = this.add( id, options );
			}

			return workflow.open();
		},

		/**
		 * Bind click event for .insert-media using event delegation
		 *
		 * @global wp.media.view.l10n
		 */
		init: function() {
			$(document.body).on( 'click', '.insert-media', function( event ) {
				var elem = $( event.currentTarget ),
					editor = elem.data('editor'),
					options = {
						frame:    'post',
						state:    'insert',
						title:    wp.media.view.l10n.addMedia,
						multiple: true
					};

				event.preventDefault();

				// Remove focus from the `.insert-media` button.
				// Prevents Opera from showing the outline of the button
				// above the modal.
				//
				// See: http://core.trac.wordpress.org/ticket/22445
				elem.blur();

				if ( elem.hasClass( 'gallery' ) ) {
					options.state = 'gallery';
					options.title = wp.media.view.l10n.createGalleryTitle;
				} else if ( elem.hasClass( 'playlist' ) ) {
					options.state = 'playlist';
					options.title = wp.media.view.l10n.createPlaylistTitle;
				} else if ( elem.hasClass( 'video-playlist' ) ) {
					options.state = 'video-playlist';
					options.title = wp.media.view.l10n.createVideoPlaylistTitle;
				}

				wp.media.editor.open( editor, options );
			});
		}
	};

	_.bindAll( wp.media.editor, 'open' );
	$( wp.media.editor.init );
}(jQuery));