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jquery.comaCollection.js

(function($){

	$.fn.comaCollection = function(){
		
		var args = Array.prototype.slice.call(arguments);
	
		if(args.length > 0 && typeof(args[0]) == 'string') {
		
			var api = $(this).data('comaCollection');
			var method = args.shift();
			
			return api[method](args);
		
		} else {
	
			this.each(function(){

				var collection = $(this);
				var items = collection.find('tbody');
				var actions = collection.find('div.actions');
				var adder = actions.find('a.add');
				var remover = actions.find('a.remove');
				var proto = collection.find('script[type="text/html"]').text();
				var count = (new Date()).getTime();

				items
				.find('td>a.remove')
				.live('click', remove);

				adder.click(add);

				remover.click(removeAll);

				check();

				function remove(event) {

					event.preventDefault();
					$(this)
					.parentsUntil('tr')
					.parent()
					.remove();

					check();

				}

				function removeAll(event) {

					event.preventDefault();
					items.empty();
					check();

				}

				function addRow(data) {

					var id = '@' + count++;

					var row = $(proto.replace(/\$\$name\$\$/g, id));
					
					$.each(data, function(i) {
						
						row.find('[name$="[' + i + ']"]').val(this);
						
					});

					return row.appendTo(items);
					

				}

				function add(event) {

					event.preventDefault();

					addRow([])
					.find('[name]:visible')
					.first()
					.focus();

					check();

				}

				function check() {

					if(items.children().length > 0) {

						actions.addClass('margen');
						remover.show();

					} else {

						actions.removeClass('margen');
						remover.hide();

					}

				}
			
				var api = {
					set: function(args) {

						items.empty();
						
						$.each(args[0], function(i) {
						
							addRow(this);

						});
						
						check();
						
						return items;

					},
					add: function(args) {
						
						return addRow(args[0]);
						
					}
				}

				collection.data('comaCollection', api);

			});

			return this;
			
		}

	}

})(jQuery);

$(function() {
	
	$('.collection').comaCollection();
	
});