	(function( $ ) {
		$.widget( "ui.combobox", {
			_create: function() {
				var input,
					that = this,
					wasOpen = false,
					select = this.element.hide(),
					selected = select.children( ":selected" ),
					value = selected.val() ? selected.text() : "",
					wrapper = this.wrapper = $( "<span>" )
						.addClass( "ui-combobox" )
						.insertAfter( select );

				function removeIfInvalid( element ) {
					var value = $( element ).val(),
						matcher = new RegExp( "^" + $.ui.autocomplete.escapeRegex( value ) + "$", "i" ),
						valid = false;
					select.children( "option" ).each(function() {
						if ( $( this ).text().match( matcher ) ) {
							this.selected = valid = true;
							return false;
						}
					});

					if ( !valid ) {
						// remove invalid value, as it didn't match anything
						$( element )
							.val( "" )
							.attr( "title", value + " didn't match any item" )
							.tooltip( "open" );
						select.val( "" );
						setTimeout(function() {
							input.tooltip( "close" ).attr( "title", "" );
						}, 2500 );
						input.data( "ui-autocomplete" ).term = "";
					}
				}

				input = $( "<input>" )
					.appendTo( wrapper )
					.val( value )
					.attr( "title", "" )
					.addClass( "ui-state-default ui-combobox-input" )
					.autocomplete({
						delay: 0,
						minLength: 0,
						source: function( request, response ) {
							var matcher = new RegExp( $.ui.autocomplete.escapeRegex(request.term), "i" );
							response( select.children( "option" ).map(function() {
								var text = $( this ).text();
								if ( this.value && ( !request.term || matcher.test(text) ) )
									return {
										label: text.replace(
											new RegExp(
												"(?![^&;]+;)(?!<[^<>]*)(" +
												$.ui.autocomplete.escapeRegex(request.term) +
												")(?![^<>]*>)(?![^&;]+;)", "gi"
											), "<strong>$1</strong>" ),
										value: text,
										option: this
									};
							}) );
						},
						select: function( event, ui ) {
							ui.item.option.selected = true;
							that._trigger( "selected", event, {
								item: ui.item.option
							});
						},
						change: function( event, ui ) {
							if ( !ui.item ) {
								removeIfInvalid( this );
							}
						}
					})
					.addClass( "ui-widget ui-widget-content ui-corner-left" );

				input.data( "ui-autocomplete" )._renderItem = function( ul, item ) {
					return $( "<li>" )
						.append( "<a>" + item.label + "</a>" )
						.appendTo( ul );
				};

				$( "<a>" )
					.attr( "tabIndex", -1 )
					.tooltip()
					.appendTo( wrapper )
					.button({
						icons: {
							primary: "ui-icon-triangle-1-s"
						},
						text: false
					})
					.removeClass( "ui-corner-all" )
					.addClass( "ui-corner-right ui-combobox-toggle" )
					.mousedown(function() {
						wasOpen = input.autocomplete( "widget" ).is( ":visible" );
					})
					.click(function() {
						input.focus();

						// close if already visible
						if ( wasOpen ) {
							return;
						}

						// pass empty string as value to search for, displaying all results
						input.autocomplete( "search", "" );
					});

				input.tooltip({
					tooltipClass: "ui-state-highlight"
				});
			},

			_destroy: function() {
				this.wrapper.remove();
				this.element.show();
			}
		});
	})( jQuery );

	$(function() {
		$( "#combobox" ).combobox();
		$( "#toggle" ).click(function() {
			$( "#combobox" ).toggle();
		});
	});