var IOCalculator = {
	
	init:function(){
	
			IOCalculator.LoanAmount 	= document.getElementById('LoanAmount');	
			IOCalculator.NoteRate 		= document.getElementById('NoteRate');	
			IOCalculator.MonthlyPayment	= document.getElementById('MonthlyPayment');		
			
			IOCalculator.addListeners();
			IOCalculator.setFields();
	},

	addListeners: function(e){
	
			IOCalculator.addEvent(this.LoanAmount, 	'blur', this.setFields, false);
			IOCalculator.addEvent(this.NoteRate, 	'blur', this.setFields, false);

	},
	
	setFields: function(){
	
		var LoanAmount 		= Number(StripCurrency(IOCalculator.LoanAmount.value));
		var NoteRate 		= Number(StripPercent(IOCalculator.NoteRate.value));
		var	MonthlyPayment	= IOCalculator.calcMonthlyInterestOnly(LoanAmount, NoteRate);
	 
		IOCalculator.LoanAmount.value 		= DollarFormat(LoanAmount);
		IOCalculator.NoteRate.value 		= PercentFormat(NoteRate,4);
		IOCalculator.MonthlyPayment.value 	= DollarFormat(MonthlyPayment);

	},		

	addEvent: function(elm, evType, fn, useCapture){
		if (elm.addEventListener){
			elm.addEventListener(evType, fn, useCapture);
			return true;
		} else if (elm.attachEvent){
			var r = elm.attachEvent('on' + evType, fn);
			return r;
		} else {
			elm['on' + evType] = fn;
		}
	},	

	calcMonthlyInterestOnly: function(LoanAmount, NoteRate){
		return (LoanAmount * (NoteRate / 100)) / 12;
	}

};

IOCalculator.addEvent(window, 'load', IOCalculator.init, false);