var CurrentCell = '';
var CellList = new Array("Amount", "APR", "Period", "Taxes", "Insurance");
function initScreen()
{
	setTimeout("window.scrollTo(0,1);",100);
}
function activatediv(DivName)
{
	CurrentCell = DivName;
	document.getElementById("keypad").style.visibility = "visible";
	switch(CurrentCell)
	{
		case "Amount":
			document.getElementById("keypad").style.top = "150px";
			setTimeout("window.scrollTo(0,120);",100);
			break;
			
		case "APR":
			document.getElementById("keypad").style.top = "180px";
			setTimeout("window.scrollTo(0,140);",100);
			break;

		case "Period":
			document.getElementById("keypad").style.top = "210px";
			setTimeout("window.scrollTo(0,180);",100);
			break;
			
		case "Taxes":
			document.getElementById("keypad").style.top = "240px";
			setTimeout("window.scrollTo(0,210);",100);
			break;

		case "Insurance":
			document.getElementById("keypad").style.top = "270px";
			setTimeout("window.scrollTo(0,240);",100);
			break;

	}
} 

function doKeypadDone()
{
	document.body.focus();
	document.getElementById("keypad").style.visibility = "hidden";
}
function doKeypadNext()
{
	var cells = CellList.length - 1;
	if(CellList[cells]==CurrentCell)
		activatediv(CellList[0]);
	else
		for (var x = 0; x<=cells; x++)
		{
			if(CellList[x]==CurrentCell)
			{
				activatediv(CellList[x +1]);
				break;
			}	
		}

}

function doKeypadPrev()
{
	var cells = CellList.length - 1;
	if(CellList[0]==CurrentCell)
		activatediv(CellList[cells]);
	else
		for (var x = cells; x>=0; x--)
		{
			if(CellList[x]==CurrentCell)
			{
				activatediv(CellList[x - 1]);
				break;
			}	
		}

}
function doKeypadCalc()
{
	Calc();
}
function Calc()
{
	document.getElementById("keypad").style.visibility = "hidden";

	var LoanAmt = Number(document.getElementById("Amount").innerHTML);
	var DownPmt =  0;//Number(document.getElementById("DownPmt").innerHTML);
	var APR = Number(document.getElementById("APR").innerHTML);
	var Period = Number(document.getElementById("Period").innerHTML);
	var Taxes = Number(document.getElementById("Taxes").innerHTML);
	var _monthlyTaxes = Taxes/12;
	var Insurance = Number(document.getElementById("Insurance").innerHTML);
	var _monthlyInsurance = Insurance/12;
	var _monthlyPayment = Number(0);
	
	if(LoanAmt == 0 | APR == 0 | Period == 0)
	{
		document.getElementById("MonthlyPayment").innerHTML = 0;
		document.getElementById("MonthlyTaxes").innerHTML = 0;
		document.getElementById("MonthlyInsurance").innerHTML = 0;
		document.getElementById("TotalPayment").innerHTML = 0;
		return;
	}
	LoanAmt = LoanAmt - DownPmt;
	APR = APR / 100 / 12;
	Period = Period * 12; //for years make switch for months vs years;
	//MonthlyPayment = (LoanAmt * APR)/(1 - (Math.pow(1 + APR, Number(0) - Period)));
	
	var tempx = (1 + APR)
	tempx = Math.pow(tempx, Period);
	
	_monthlyPayment = LoanAmt * (APR * tempx/(tempx - 1));
	//MonthlyPayment = MonthlyPayment + Taxes + Insurance;
	
	document.getElementById("MonthlyPayment").innerHTML = Math.round(_monthlyPayment*100)/100;
	if(Taxes != 0)
		document.getElementById("MonthlyTaxes").innerHTML = Math.round(_monthlyTaxes*100)/100;
	else
	{
		document.getElementById("MonthlyTaxes").innerHTML = 0;
		_monthlyTaxes = 0;
	}
	if(Insurance != 0)
		document.getElementById("MonthlyInsurance").innerHTML = Math.round(_monthlyInsurance*100)/100;
	else
	{
		document.getElementById("MonthlyInsurance").innerHTML = 0;
		_monthlyInsurance = 0;
	}
	
	document.getElementById("TotalPayment").innerHTML = Math.round((_monthlyPayment + _monthlyTaxes + _monthlyInsurance)*100)/100;
	
	//alert(APR);
	//alert(MonthlyPayment);
}



/*Keypad Functions */
function click_zero() {	_appendDigit("0"); }
function click_one() {	_appendDigit("1"); }
function click_two() {	_appendDigit("2"); }
function click_three() {	_appendDigit("3"); }
function click_four() {	_appendDigit("4"); }
function click_five() {	_appendDigit("5"); }
function click_six() {	_appendDigit("6"); }
function click_seven() {	_appendDigit("7"); }
function click_eight() {	_appendDigit("8"); }
function click_nine() {	_appendDigit("9"); }

function click_point() { 
	var DigitsSoFar = document.getElementById(CurrentCell).innerHTML;
	if(DigitsSoFar == "0")
		_appendDigit("0.");
	else if (DigitsSoFar == "0.0")
		return;
	else
		{
		//alert(DigitsSoFar.indexOf(".") == -1);
		if(DigitsSoFar.indexOf(".") == -1)
			{
				//alert(".");
				_appendDigit(".");
			}
	 	}
	 }


function _appendDigit(Digit)
{
	//alert(Digit);
	//alert(CurrentCell);
	var DigitsSoFar = document.getElementById(CurrentCell).innerHTML;
	//alert(DigitsSoFar)
	/*if(document.getElementById("arithfunction").innerHTML == "")
	{
		var ClearDigits = document.getElementById("cleardigitsbit").innerHTML;
		if(ClearDigits == "Y")
			{
				document.getElementById(CurrentCell).innerHTML = Digit;
				document.getElementById("cleardigitsbit").innerHTML = "N";
			}
		else 
		*/
		if(DigitsSoFar == "0" | DigitsSoFar == "0.0")
			document.getElementById(CurrentCell).innerHTML = Digit;
		else
			document.getElementById(CurrentCell).innerHTML = DigitsSoFar + Digit;
	/*
	}
	else
	{
		document.getElementById("currentarith").innerHTML = document.getElementById("arithfunction").innerHTML
		document.getElementById("arithfunction").innerHTML = "";
		document.getElementById(CurrentCell).innerHTML = Digit;
	}
	*/
	//alert("Click() " + DigitsSoFar);
	
}

function click_clear()
{
	document.getElementById(CurrentCell).innerHTML = "0";
//	document.getElementById("yval").innerHTML = "0";
//	document.getElementById("xval").innerHTML = "0";
//	document.getElementById("arithfunction").innerHTML = "";
//	document.getElementById("currentarith").innerHTML = "";
	//document.getElementById("arithfunction").innerHTML = "";
}

function click_allclear()
{
	var cells = CellList.length - 1;
	for (var x = 0; x<=cells; x++)
	{
		document.getElementById(CellList[x]).innerHTML = 0;
	}
	document.getElementById("Period").innerHTML = 30;
	document.getElementById("MonthlyPayment").innerHTML = "&nbsp;";
	document.getElementById("MonthlyTaxes").innerHTML = "&nbsp;";
	document.getElementById("MonthlyInsurance").innerHTML = "&nbsp;";
	document.getElementById("TotalPayment").innerHTML = "&nbsp;";

	
}

function click_backsp()
{

	var DigitsSoFar = document.getElementById(CurrentCell).innerHTML;
	
	if (DigitsSoFar == "0" | DigitsSoFar == "0.0" | DigitsSoFar ==".0")	
		return;
	else 
	{
		if(DigitsSoFar.length > 1)
			document.getElementById(CurrentCell).innerHTML = DigitsSoFar.substring(0 ,DigitsSoFar.length-1)
		else
			document.getElementById(CurrentCell).innerHTML = "0";
	}
}