function Booking_system() {

	// initialize the member function references
	this.create_booking_system = create_booking_system;
 	this.display_booking_system = display_booking_system;
	this.close_booking_system=close_booking_system;
    this.get_page_scroll=get_page_scroll;
    this.get_page_height=get_page_height;
    
    pay = new Pay();
	calendar = new Calendar(pay);
	booking_form = new Booking_form(calendar);
	price = new Price();
    contact = new Contact();
	
	//define methods
	function create_booking_system() {
		$("#booking_system").click(function(){
			$("#booking_system").css('visibility', 'hidden');
			display_booking_system();
		});
	}
		
	function display_booking_system() {
		$('<div>').attr('id', 'overlay').attr('class', 'overlay').appendTo('body');
        var y_scroll = get_page_scroll();
        if (y_scroll != 0) {
        	var page_height = get_page_height();
            var overlay_height = page_height+y_scroll;
            $('#overlay').css('height', overlay_height);
        } 
        $('#overlay').fadeIn("medium",function(){
        	$('<img>').attr('id', 'booking_system_loader').attr('src', 'http://www.rocklandsboulders.com/images/booking_system_loader.gif').attr('style','left:525px;top:230px;position:absolute;z-index:100;').appendTo('#main-container');
            $('<div>').attr('id', 'tabs').attr('class', 'tabs').appendTo('#main-container');
            $('#tabs').html('<ul id="tabs-list"><li><a id="avail_link" href="#fragment-1" tabindex="1">check availability</a></li><li><a id="details_link" href="#fragment-2" tabindex="2">complete details</a></li><li><a href="#fragment-3" id="pay_link" tabindex="3">pay</a></li><li><a id="price_link" href="#fragment-4" tabindex="4">pricing</a></li><li><a id="contact_link" href="#fragment-5" tabindex="5">contact</a></li></ul><div id="fragment-1"></div><div id="fragment-2"></div><div id="fragment-3"></div><div id="fragment-4"></div><div id="fragment-5"></div>');
            $('<div>').attr('id', 'all-payment-info').appendTo('#fragment-3');
            $('#all-payment-info').append('<p id="pay_details" class="div-text-holder-blue" style="margin-top:0;font-weight:bold;">PayPal</p>');
            $('<div>').attr('id', 'close-booking-system').attr('style', '').prependTo('#tabs');
            $('#close-booking-system').html('<a href="javascript:void(0);" id="close_booking_system" class="close-booking-system" tabindex="6" title="close">close</a>');		
            close_booking_system();
            $('<div>').attr('id', 'check_progress').attr('style', 'background-color:#fff;color:#000;position:absolute;z-index:200;top:0;display:none;').appendTo('main-container');
            booking_form.get_booking_form_info();
            price.create_price_tab();
            contact.create_contact_tab();
        });
	}
	
	function close_booking_system() {
		$('#close_booking_system').click(function() {
			$('#tabs').fadeOut('slow', function() {
                $('#overlay').fadeOut('slow', function() {
                    $('#overlay').remove();
                    $('#tabs').remove();
                    $('#booking_system').css('visibility', 'visible');
				});
			});
			
		});
	}
    
    function get_page_scroll() {
			var yScroll;
			if (self.pageYOffset) {
				yScroll = self.pageYOffset;
			} else if (document.documentElement && document.documentElement.scrollTop) {	 // Explorer 6 Strict
				yScroll = document.documentElement.scrollTop;
			} else if (document.body) {// all other Explorers
				yScroll = document.body.scrollTop;
			}
			return yScroll;
		};
        
    function get_page_height() {
    	var windowHeight;
        if (self.innerHeight) {	// all except Explorer
            windowHeight = self.innerHeight;
        } else if (document.documentElement && document.documentElement.clientHeight) { // Explorer 6 Strict Mode
            windowHeight = document.documentElement.clientHeight;
        } else if (document.body) { // other Explorers
            windowHeight = document.body.clientHeight;
        }	
     	return windowHeight;			
    }
}