$(document).ready(function(){
	var result1 = 0;
	var result2 = 0;
	var result = 0;
	
	$("input").change( function() {
		$(this).removeClass('empty_box');
		var val = $.trim($(this).val());
		if(val != '') {
			val = parseFloat(val);
		}
		if(isNaN(val)) {
			val = 'Error';
			$(this).addClass('empty_box');
		}
		$(this).attr("value", val);
	});
	 
	$('#calc_form'). submit(function() {
		$("input").removeClass('empty_box');									  
		
		var cost_pp = jQuery.trim($("#cost_pp").val());
		var guests = jQuery.trim($("#guests").val());
		var clients = jQuery.trim($("#clients").val());
		var revenue = jQuery.trim($("#revenue").val());
		
		if(cost_pp == '' || guests == '' || clients == '' || revenue == '') {
			$("input[value='']").addClass('empty_box');
			return false;
		}
		
		cost_pp = parseFloat(cost_pp);
		guests = parseFloat(guests);
		clients = parseFloat(clients);
		revenue = parseFloat(revenue);
		isNaN
		
		if(isNaN(cost_pp) || isNaN(guests) || isNaN(clients) || isNaN(revenue)) {
			//$("input[value='']").addClass('empty_box');
			return false;
		}
		
		
		var total_spend = (cost_pp * guests);
		$('#total_spend').html('£ ' + total_spend);
		
		var total_revenue =  (clients * revenue);
		$('#total_revenue').html('£ ' + total_revenue);
		
		var turnover = (total_revenue - total_spend);
		$('#turnover').html('£ ' + turnover);
		
		var turnover_percent = Math.round((turnover/total_spend)*100);
		$('#turnover_percent').html(turnover_percent + '%');
		
		return false;
	});
});