window.onload = function() {
	function all_selected() {
		var all_selected = true;
		$('input[name="cb_basketitem"]').each(function() {
			all_selected &= $(this).attr('checked');
		});
		return all_selected;
	}
	
	function update_num_selected() {
		$('span#num-selected').text($('input[name="cb_basketitem"]:checked').length);
	}
	
	$('ul.tools').after('<p><label for="select_all">Select all</label><input type="checkbox" id="select_all" /></p>');
	$('input#select_all').click(function() {
		var new_state = $(this).attr('checked');
		$('input[name="cb_basketitem"]').attr('checked', new_state);
		update_num_selected();
	});
	$('input[name="cb_basketitem"]').click(function() {
		$('#select_all').attr('checked', all_selected());
		update_num_selected();
	});
	$('#actions_container fieldset').prepend('<p><span id="num-selected">'+$('input[name="cb_basketitem"]:checked').length+'</span> items selected.</p>');
};