var slideshow = {
  validate: function(slideshow) {
    var title = $(slideshow+'_title');
    var slideshowSubmit = $('slideshow_submit');
    var errors = "";
    if (title.value == "") {
      title.setStyle({backgroundColor: "#FFFDBB"});
			errors += "* Please enter a title\n";
		}
    if (errors == "") {
		  slideshowSubmit.value = "Processing...";
			return true;
		} else {
			alert("Please fix the following errors:\n"+errors);
			return false;
		}
  }
}
function MultiSelector(list_target, max) {
  this.list_target = list_target;
	this.count = 0;
	this.id = 0;if( max ){
		this.max = max;
	} else {
		this.max = -1;
	};
	this.addElement = function( element ){
		if( element.tagName == 'INPUT' && element.type == 'file' ){
			element.name = 'attachment[file_' + (this.id++) + ']';
			element.multi_selector = this;
			element.onchange = function(){
				var new_element = document.createElement( 'input' );
				new_element.type = 'file';
				this.parentNode.insertBefore( new_element, this );
				this.multi_selector.addElement( new_element );
				this.multi_selector.addListRow( this );
				this.style.position = 'absolute';
				this.style.left = '-1000px';
			};
			if( this.max != -1 && this.count >= this.max ){
				element.disabled = true;
			};
			this.count++;
			this.current_element = element;
		} else {
			alert( 'Error: not a file input element' );
		};
	};
	this.addListRow = function( element ){
		var new_row = document.createElement('li');
		var new_row_button = document.createElement( 'a' );
		new_row_button.title = 'Remove This Image';
		new_row_button.href = '#';
		new_row_button.innerHTML = 'Remove';
		new_row.element = element;
		new_row_button.onclick= function(){
			this.parentNode.element.parentNode.removeChild( this.parentNode.element );
			this.parentNode.parentNode.removeChild( this.parentNode );
			this.parentNode.element.multi_selector.count--;
			this.parentNode.element.multi_selector.current_element.disabled = false;
			return false;
		};
		new_row.innerHTML = element.value.split('/')[element.value.split('/').length - 1];
		new_row.appendChild( new_row_button );this.list_target.appendChild( new_row );
	};
}