/* global pluploadL10n, plupload, _wpPluploadSettings */

/**

 * @namespace wp

 */

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

( function( exports, $ ) {

	var Uploader;

	if ( typeof _wpPluploadSettings === 'undefined' ) {

		return;

	}

	/**

	 * A WordPress uploader.

	 *

	 * The Plupload library provides cross-browser uploader UI integration.

	 * This object bridges the Plupload API to integrate uploads into the

	 * WordPress back end and the WordPress media experience.

	 *

	 * @class

	 * @memberOf wp

	 * @alias wp.Uploader

	 *

	 * @param {object} options           The options passed to the new plupload instance.

	 * @param {object} options.container The id of uploader container.

	 * @param {object} options.browser   The id of button to trigger the file select.

	 * @param {object} options.dropzone  The id of file drop target.

	 * @param {object} options.plupload  An object of parameters to pass to the plupload instance.

	 * @param {object} options.params    An object of parameters to pass to $_POST when uploading the file.

	 *                                   Extends this.plupload.multipart_params under the hood.

	 */

	Uploader = function( options ) {

		var self = this,

			elements = {

				container: 'container',

				browser:   'browse_button',

				dropzone:  'drop_element'

			},

		this.supports = {

			upload: Uploader.browser.supported

		};

		this.supported = this.supports.upload;

		if ( ! this.supported ) {

			return;

		}

		// Arguments to send to pluplad.Uploader().

		// Use deep extend to ensure that multipart_params and other objects are cloned.

		this.plupload = $.extend( true, { multipart_params: {} }, Uploader.defaults );

		this.container = document.body; // Set default container.

		$.extend( true, this, options );

		// Proxy all methods so this always refers to the current instance.

		for ( key in this ) {

			if ( $.isFunction( this[ key ] ) ) {

				this[ key ] = $.proxy( this[ key ], this );

			}

		}

		// Ensure all elements are jQuery elements and have id attributes,

		// then set the proper plupload arguments to the ids.

		for ( key in elements ) {

			if ( ! this[ key ] ) {

				continue;

			}

			this[ key ] = $( this[ key ] ).first();

			if ( ! this[ key ].length ) {

				delete this[ key ];

				continue;

			}

			if ( ! this[ key ].prop('id') ) {

				this[ key ].prop( 'id', '__wp-uploader-id-' + Uploader.uuid++ );

			}

			this.plupload[ elements[ key ] ] = this[ key ].prop('id');

		}

		// If the uploader has neither a browse button nor a dropzone, bail.

		if ( ! ( this.browser && this.browser.length ) && ! ( this.dropzone && this.dropzone.length ) ) {

			return;

		}

		// Initialize the plupload instance.

		this.uploader = new plupload.Uploader( this.plupload );

		delete this.plupload;

		// Set default params and remove this.params alias.

		this.param( this.params || {} );

		delete this.params;

		/**

		 * Custom error callback.

		 *

		 * Add a new error to the errors collection, so other modules can track

		 * and display errors. @see wp.Uploader.errors.

		 *

		 */

			if ( file.attachment ) {

				file.attachment.destroy();

			}

			Uploader.errors.unshift({

				message: message || pluploadL10n.default_error,

				data:    data,

				file:    file

			});

			self.error( message, data, file );

		};

		/**

		 * After the Uploader has been initialized, initialize some behaviors for the dropzone.

		 *

		 * @param {plupload.Uploader} uploader Uploader instance.

		 */

		this.uploader.bind( 'init', function( uploader ) {

			var timer, active, dragdrop,

				dropzone = self.dropzone;

			dragdrop = self.supports.dragdrop = uploader.features.dragdrop && ! Uploader.browser.mobile;

			// Generate drag/drop helper classes.

			if ( ! dropzone ) {

				return;

			}

			dropzone.toggleClass( 'supports-drag-drop', !! dragdrop );

			if ( ! dragdrop ) {

				return dropzone.unbind('.wp-uploader');

			}

			// 'dragenter' doesn't fire correctly, simulate it with a limited 'dragover'.

			dropzone.bind( 'dragover.wp-uploader', function() {

				if ( timer ) {

					clearTimeout( timer );

				}

				if ( active ) {

					return;

				}

				dropzone.trigger('dropzone:enter').addClass('drag-over');

				active = true;

			});

			dropzone.bind('dragleave.wp-uploader, drop.wp-uploader', function() {

				timer = setTimeout( function() {

					active = false;

					dropzone.trigger('dropzone:leave').removeClass('drag-over');

				}, 0 );

			});

			self.ready = true;

			$(self).trigger( 'uploader:ready' );

		});

		this.uploader.bind( 'postinit', function( up ) {

			up.refresh();

			self.init();

		});

		this.uploader.init();

		if ( this.browser ) {

			this.browser.on( 'mouseenter', this.refresh );

		} else {

			this.uploader.disableBrowse( true );

		}

		/**

		 * After files were filtered and added to the queue, create a model for each.

		 *

		 */

		this.uploader.bind( 'FilesAdded', function( up, files ) {

			_.each( files, function( file ) {

				var attributes, image;

				// Ignore failed uploads.

				if ( plupload.FAILED === file.status ) {

					return;

				}

				// Generate attributes for a new `Attachment` model.

				attributes = _.extend({