window.addEvent('domready',function()
{
	var issue = 1000;
	var subscription = 3500;
	var total = 3500;
	
	var discount = $('discount').value;
	
	if(discount != 0)
	{
		issue = Math.floor((issue/100) * (100-discount));	
		subscription = Math.floor((subscription/100) * (100-discount));	
		total = Math.floor((total/100) * (100-discount));	
		$('subscription_value').value = subscription;
	}
	
	var total_length = String(total).length;
	var pounds = String(total).substring(0, total_length - 2);
	var pence = String(total).substring(total_length - 2, total_length);
	
	updateSubtotal();
	
	/*form quantity*/
	$('content-container').getElements('.subtract').addEvent('click',function()
	{
		updateQuantity(this, 'subtract');
	});
	
	$('content-container').getElements('img.add').addEvent('click',function()
	{
		updateQuantity(this, 'add');
	});
	
	function updateQuantity(object, action)
	{
		if(action == 'add')
		{
			var input = object.getPrevious();
			var currentValue = parseInt(input.value);
			currentValue = currentValue + 1;
			
			var trueValue = String(input.id+'_value');
			
			if(input.id == 'subscription')
			{
				$(trueValue).value = subscription * currentValue;
			}
			else
			{
				$(trueValue).value = issue * currentValue;
			}
		}
		else
		{
			var input = object.getNext();
			var currentValue = parseInt(input.value);
			currentValue = currentValue - 1;
			
			var trueValue = String(input.id+'_value');

			if(currentValue >= 0)
			{
				if(input.id == 'subscription')
				{
					$(trueValue).value = subscription * currentValue;
				}
				else
				{
					$(trueValue).value = issue * currentValue;
				}
			}
		}
		
		if(currentValue >= 0)
		{
			input.value = currentValue;
		}
		
		updateSubtotal();
		
	}
	
	function updateSubtotal()
	{
		var subtotals = $('content-container').getElements('.subtotal-value');
		var running_total = 0;
		for(var i=0; i<subtotals.length; i++)
		{
			//console.log('Before: '+running_total);
			running_total = running_total + parseFloat(subtotals[i].value);
			
			
			/*console.log('Value: '+subtotals[i].value);
			console.log('After: '+running_total);
			console.log('               ');*/
		}
		
		var total_length = String(running_total).length;
		var pounds = String(running_total).substring(0, total_length - 2);
		var pence = String(running_total).substring(total_length - 2, total_length);
		
		$('subtotal-value').innerHTML = pounds+'.'+pence;	
		
		if( (pounds+'.'+pence) == '.0')
		{
			$('subtotal-value').innerHTML = '0.00';	
		}
	}
	
	/*scroll*/
	var currentLeft = 0;
	var viewWidth = 381;
	var multiples = 129;
	
	var totalWidth = $('back-issue-viewfinder').getStyle('width');
	totalWidth = totalWidth.replace('px','');
	
	var items = $('back-issue-viewfinder').getElements('.back-issue-item');
	var items = items.length;
	
	
	var maxLeft = 0;
	var minLeft = 0 - ((totalWidth - viewWidth));
	
	var viewFinder = $('back-issue-viewfinder');
	var viewFinderScroll = new Fx.Tween(viewFinder, {duration:400});
	
	$('scroll-right').addEvent('click',function()
	{
		if((currentLeft - multiples) >= minLeft)
		{
			viewFinderScroll.start('left', currentLeft - multiples);
			currentLeft = currentLeft - multiples;
		}
	});
	
	$('scroll-left').addEvent('click',function()
	{
		if((currentLeft + multiples) <= maxLeft)
		{
			viewFinderScroll.start('left', currentLeft + multiples);
			currentLeft = currentLeft + multiples;
		}
	});
	
	/*** tooltips ***/
	var myTips = new Tips('.back-issue-img', {
		title: function(object)
		{
			var description = object.getNext();
			return description.innerHTML;
		},
		className: 'back-issue-tip'
	});
	
});