var View = wp.media.View,
	$ = jQuery,
	Attachment;

/**
 * wp.media.view.Attachment
 *
 * @memberOf wp.media.view
 *
 * @class
 * @augments wp.media.View
 * @augments wp.Backbone.View
 * @augments Backbone.View
 */
Attachment = View.extend(/** @lends wp.media.view.Attachment.prototype */{
	tagName:   'li',
	className: 'attachment',
	template:  wp.template('attachment'),

	attributes: function() {
		return {
			'tabIndex':     0,
			'role':         'checkbox',
			'aria-label':   this.model.get( 'title' ),
			'aria-checked': false,
			'data-id':      this.model.get( 'id' )
		};
	},

	events: {
		'click':                          'toggleSelectionHandler',
		'change [data-setting]':          'updateSetting',
		'change [data-setting] input':    'updateSetting',
		'change [data-setting] select':   'updateSetting',
		'change [data-setting] textarea': 'updateSetting',
		'click .attachment-close':        'removeFromLibrary',
		'click .check':                   'checkClickHandler',
		'keydown':                        'toggleSelectionHandler'
	},

	buttons: {},

	initialize: function() {
		var selection = this.options.selection,
			options = _.defaults( this.options, {
				rerenderOnModelChange: true
			} );

		if ( options.rerenderOnModelChange ) {
			this.listenTo( this.model, 'change', this.render );
		} else {
			this.listenTo( this.model, 'change:percent', this.progress );
		}
		this.listenTo( this.model, 'change:title', this._syncTitle );
		this.listenTo( this.model, 'change:caption', this._syncCaption );
		this.listenTo( this.model, 'change:artist', this._syncArtist );
		this.listenTo( this.model, 'change:album', this._syncAlbum );

		// Update the selection.
		this.listenTo( this.model, 'add', this.select );
		this.listenTo( this.model, 'remove', this.deselect );
		if ( selection ) {
			selection.on( 'reset', this.updateSelect, this );
			// Update the model's details view.
			this.listenTo( this.model, 'selection:single selection:unsingle', this.details );
			this.details( this.model, this.controller.state().get('selection') );
		}

		this.listenTo( this.controller.states, 'attachment:compat:waiting attachment:compat:ready', this.updateSave );
	},
	/**
	 * @return {wp.media.view.Attachment} Returns itself to allow chaining.
	 */
	dispose: function() {
		var selection = this.options.selection;

		// Make sure all settings are saved before removing the view.
		this.updateAll();

		if ( selection ) {
			selection.off( null, null, this );
		}
		/**
		 * call 'dispose' directly on the parent class
		 */
		View.prototype.dispose.apply( this, arguments );
		return this;
	},
	/**
	 * @return {wp.media.view.Attachment} Returns itself to allow chaining.
	 */
	render: function() {
		var options = _.defaults( this.model.toJSON(), {
				orientation:   'landscape',
				uploading:     false,
				type:          '',
				subtype:       '',
				icon:          '',
				filename:      '',
				caption:       '',
				title:         '',
				dateFormatted: '',
				width:         '',
				height:        '',
				compat:        false,
				alt:           '',
				description:   ''
			}, this.options );

		options.buttons  = this.buttons;
		options.describe = this.controller.state().get('describe');

		if ( 'image' === options.type ) {
			options.size = this.imageSize();
		}

		options.can = {};
		if ( options.nonces ) {
			options.can.remove = !! options.nonces['delete'];
			options.can.save = !! options.nonces.update;
		}

		if ( this.controller.state().get('allowLocalEdits') ) {
			options.allowLocalEdits = true;
		}

		if ( options.uploading && ! options.percent ) {
			options.percent = 0;
		}

		this.views.detach();
		this.$el.html( this.template( options ) );

		this.$el.toggleClass( 'uploading', options.uploading );

		if ( options.uploading ) {
			this.$bar = this.$('.media-progress-bar div');
		} else {
			delete this.$bar;
		}

		// Check if the model is selected.
		this.updateSelect();

		// Update the save status.
		this.updateSave();

		this.views.render();

		return this;
	},

	progress: function() {
		if ( this.$bar && this.$bar.length ) {
			this.$bar.width( this.model.get('percent') + '%' );
		}
	},

	/**
	 * @param {Object} event
	 */
	toggleSelectionHandler: function( event ) {
		var method;

		// Don't do anything inside inputs and on the attachment check and remove buttons.
		if ( 'INPUT' === event.target.nodeName || 'BUTTON' === event.target.nodeName ) {
			return;
		}

		// Catch arrow events.
		if ( 37 === event.keyCode || 38 === event.keyCode || 39 === event.keyCode || 40 === event.keyCode ) {
			this.controller.trigger( 'attachment:keydown:arrow', event );
			return;
		}

		// Catch enter and space events.
		if ( 'keydown' === event.type && 13 !== event.keyCode && 32 !== event.keyCode ) {
			return;
		}

		event.preventDefault();

		// In the grid view, bubble up an edit:attachment event to the controller.
		if ( this.controller.isModeActive( 'grid' ) ) {
			if ( this.controller.isModeActive( 'edit' ) ) {
				// Pass the current target to restore focus when closing.
				this.controller.trigger( 'edit:attachment', this.model, event.currentTarget );
				return;
			}

			if ( this.controller.isModeActive( 'select' ) ) {
				method = 'toggle';
			}
		}

		if ( event.shiftKey ) {
			method = 'between';
		} else if ( event.ctrlKey || event.metaKey ) {
			method = 'toggle';
		}

		this.toggleSelection({
			method: method
		});

		this.controller.trigger( 'selection:toggle' );
	},
	/**
	 * @param {Object} options
	 */
	toggleSelection: function( options ) {
		var collection = this.collection,
			selection = this.options.selection,
			model = this.model,
			method = options && options.method,
			single, models, singleIndex, modelIndex;

		if ( ! selection ) {
			return;
		}

		single = selection.single();
		method = _.isUndefined( method ) ? selection.multiple : method;

		// If the `method` is set to `between`, select all models that
		// exist between the current and the selected model.
		if ( 'between' === method && single && selection.multiple ) {
			// If the models are the same, short-circuit.
			if ( single === model ) {
				return;
			}

			singleIndex = collection.indexOf( single );
			modelIndex  = collection.indexOf( this.model );

			if ( singleIndex < modelIndex ) {
				models = collection.models.slice( singleIndex, modelIndex + 1 );
			} else {
				models = collection.models.slice( modelIndex, singleIndex + 1 );
			}

			selection.add( models );
			selection.single( model );
			return;

		// If the `method` is set to `toggle`, just flip the selection
		// status, regardless of whether the model is the single model.
		} else if ( 'toggle' === method ) {
			selection[ this.selected() ? 'remove' : 'add' ]( model );
			selection.single( model );
			return;
		} else if ( 'add' === method ) {
			selection.add( model );
			selection.single( model );
			return;
		}

		// Fixes bug that loses focus when selecting a featured image.
		if ( ! method ) {
			method = 'add';
		}

		if ( method !== 'add' ) {
			method = 'reset';
		}

		if ( this.selected() ) {
			/*
			 * If the model is the single model, remove it.
			 * If it is not the same as the single model,
			 * it now becomes the single model.
			 */
			selection[ single === model ? 'remove' : 'single' ]( model );
		} else {
			/*
			 * If the model is not selected, run the `method` on the
			 * selection. By default, we `reset` the selection, but the
			 * `method` can be set to `add` the model to the selection.
			 */
			selection[ method ]( model );
			selection.single( model );
		}
	},

	updateSelect: function() {
		this[ this.selected() ? 'select' : 'deselect' ]();
	},
	/**
	 * @return {unresolved|Boolean}
	 */
	selected: function() {
		var selection = this.options.selection;
		if ( selection ) {
			return !! selection.get( this.model.cid );
		}
	},
	/**
	 * @param {Backbone.Model} model
	 * @param {Backbone.Collection} collection
	 */
	select: function( model, collection ) {
		var selection = this.options.selection,
			controller = this.controller;

		/*
		 * Check if a selection exists and if it's the collection provided.
		 * If they're not the same collection, bail; we're in another
		 * selection's event loop.
		 */
		if ( ! selection || ( collection && collection !== selection ) ) {
			return;
		}

		// Bail if the model is already selected.
		if ( this.$el.hasClass( 'selected' ) ) {
			return;
		}

		// Add 'selected' class to model, set aria-checked to true.
		this.$el.addClass( 'selected' ).attr( 'aria-checked', true );
		//  Make the checkbox tabable, except in media grid (bulk select mode).
		if ( ! ( controller.isModeActive( 'grid' ) && controller.isModeActive( 'select' ) ) ) {
			this.$( '.check' ).attr( 'tabindex', '0' );
		}
	},
	/**
	 * @param {Backbone.Model} model
	 * @param {Backbone.Collection} collection
	 */
	deselect: function( model, collection ) {
		var selection = this.options.selection;

		/*
		 * Check if a selection exists and if it's the collection provided.
		 * If they're not the same collection, bail; we're in another
		 * selection's event loop.
		 */
		if ( ! selection || ( collection && collection !== selection ) ) {
			return;
		}
		this.$el.removeClass( 'selected' ).attr( 'aria-checked', false )
			.find( '.check' ).attr( 'tabindex', '-1' );
	},
	/**
	 * @param {Backbone.Model} model
	 * @param {Backbone.Collection} collection
	 */
	details: function( model, collection ) {
		var selection = this.options.selection,
			details;

		if ( selection !== collection ) {
			return;
		}

		details = selection.single();
		this.$el.toggleClass( 'details', details === this.model );
	},
	/**
	 * @param {string} size
	 * @return {Object}
	 */
	imageSize: function( size ) {
		var sizes = this.model.get('sizes'), matched = false;

		size = size || 'medium';

		// Use the provided image size if possible.
		if ( sizes ) {
			if ( sizes[ size ] ) {
				matched = sizes[ size ];
			} else if ( sizes.large ) {
				matched = sizes.large;
			} else if ( sizes.thumbnail ) {
				matched = sizes.thumbnail;
			} else if ( sizes.full ) {
				matched = sizes.full;
			}

			if ( matched ) {
				return _.clone( matched );
			}
		}

		return {
			url:         this.model.get('url'),
			width:       this.model.get('width'),
			height:      this.model.get('height'),
			orientation: this.model.get('orientation')
		};
	},
	/**
	 * @param {Object} event
	 */
	updateSetting: function( event ) {
		var $setting = $( event.target ).closest('[data-setting]'),
			setting, value;

		if ( ! $setting.length ) {
			return;
		}

		setting = $setting.data('setting');
		value   = event.target.value;

		if ( this.model.get( setting ) !== value ) {
			this.save( setting, value );
		}
	},

	/**
	 * Pass all the arguments to the model's save method.
	 *
	 * Records the aggregate status of all save requests and updates the
	 * view's classes accordingly.
	 */
	save: function() {
		var view = this,
			save = this._save = this._save || { status: 'ready' },
			request = this.model.save.apply( this.model, arguments ),
			requests = save.requests ? $.when( request, save.requests ) : request;

		// If we're waiting to remove 'Saved.', stop.
		if ( save.savedTimer ) {
			clearTimeout( save.savedTimer );
		}

		this.updateSave('waiting');
		save.requests = requests;
		requests.always( function() {
			// If we've performed another request since this one, bail.
			if ( save.requests !== requests ) {
				return;
			}

			view.updateSave( requests.state() === 'resolved' ? 'complete' : 'error' );
			save.savedTimer = setTimeout( function() {
				view.updateSave('ready');
				delete save.savedTimer;
			}, 2000 );
		});
	},
	/**
	 * @param {string} status
	 * @return {wp.media.view.Attachment} Returns itself to allow chaining.
	 */
	updateSave: function( status ) {
		var save = this._save = this._save || { status: 'ready' };

		if ( status && status !== save.status ) {
			this.$el.removeClass( 'save-' + save.status );
			save.status = status;
		}

		this.$el.addClass( 'save-' + save.status );
		return this;
	},

	updateAll: function() {
		var $settings = this.$('[data-setting]'),
			model = this.model,
			changed;

		changed = _.chain( $settings ).map( function( el ) {
			var $input = $('input, textarea, select, [value]', el ),
				setting, value;

			if ( ! $input.length ) {
				return;
			}

			setting = $(el).data('setting');
			value = $input.val();

			// Record the value if it changed.
			if ( model.get( setting ) !== value ) {
				return [ setting, value ];
			}
		}).compact().object().value();

		if ( ! _.isEmpty( changed ) ) {
			model.save( changed );
		}
	},
	/**
	 * @param {Object} event
	 */
	removeFromLibrary: function( event ) {
		// Catch enter and space events.
		if ( 'keydown' === event.type && 13 !== event.keyCode && 32 !== event.keyCode ) {
			return;
		}

		// Stop propagation so the model isn't selected.
		event.stopPropagation();

		this.collection.remove( this.model );
	},

	/**
	 * Add the model if it isn't in the selection, if it is in the selection,
	 * remove it.
	 *
	 * @param  {[type]} event [description]
	 * @return {[type]}       [description]
	 */
	checkClickHandler: function ( event ) {
		var selection = this.options.selection;
		if ( ! selection ) {
			return;
		}
		event.stopPropagation();
		if ( selection.where( { id: this.model.get( 'id' ) } ).length ) {
			selection.remove( this.model );
			// Move focus back to the attachment tile (from the check).
			this.$el.focus();
		} else {
			selection.add( this.model );
		}

		// Trigger an action button update.
		this.controller.trigger( 'selection:toggle' );
	}
});

// Ensure settings remain in sync between attachment views.
_.each({
	caption: '_syncCaption',
	title:   '_syncTitle',
	artist:  '_syncArtist',
	album:   '_syncAlbum'
}, function( method, setting ) {
	/**
	 * @function _syncCaption
	 * @memberOf wp.media.view.Attachment
	 * @instance
	 *
	 * @param {Backbone.Model} model
	 * @param {string} value
	 * @return {wp.media.view.Attachment} Returns itself to allow chaining.
	 */
	/**
	 * @function _syncTitle
	 * @memberOf wp.media.view.Attachment
	 * @instance
	 *
	 * @param {Backbone.Model} model
	 * @param {string} value
	 * @return {wp.media.view.Attachment} Returns itself to allow chaining.
	 */
	/**
	 * @function _syncArtist
	 * @memberOf wp.media.view.Attachment
	 * @instance
	 *
	 * @param {Backbone.Model} model
	 * @param {string} value
	 * @return {wp.media.view.Attachment} Returns itself to allow chaining.
	 */
	/**
	 * @function _syncAlbum
	 * @memberOf wp.media.view.Attachment
	 * @instance
	 *
	 * @param {Backbone.Model} model
	 * @param {string} value
	 * @return {wp.media.view.Attachment} Returns itself to allow chaining.
	 */
	Attachment.prototype[ method ] = function( model, value ) {
		var $setting = this.$('[data-setting="' + setting + '"]');

		if ( ! $setting.length ) {
			return this;
		}

		/*
		 * If the updated value is in sync with the value in the DOM, there
		 * is no need to re-render. If we're currently editing the value,
		 * it will automatically be in sync, suppressing the re-render for
		 * the view we're editing, while updating any others.
		 */
		if ( value === $setting.find('input, textarea, select, [value]').val() ) {
			return this;
		}

		return this.render();
	};
});

module.exports = Attachment;
