//*******************************************
//DO NOT REMOVE THIS COPYWRITE INFO!
//Automobile Affordability Calculator
//2002 Daniel C. Peterson ALL RIGHTS RESERVED
//Created: 12/14/2002
//Last Modified: 12/14/2002
//This script may not be copied, edited, distributed or reproduced
//without express written permission from
//Daniel C. Peterson of Web Winder Website Services
//For commercial use rates, contact:
//Dan Peterson:
//Web Winder Website Services
//P.O. Box 11
//Bemidji, MN  56619
//dan@webwinder.com
//http://www.webwinder.com
//Commercial User Licence #:5782-1237-88-1198
//Commercial Licence Date:2008-09-11
//*******************************************



function stripNum(num) {

   num=num.toString();


   var len = num.length;
   var rnum = "";
   var test = "";
   var j = 0;

   var b = num.substring(0,1);
   if(b == "-") {
      rnum = "-";
   }

   for(i = 0; i <= len; i++) {

      b = num.substring(i,i+1);

      if(b == "0" || b == "1" || b == "2" || b == "3" || b == "4" || b == "5" || b == "6" || b == "7" || b == "8" || b == "9" || b == ".") {
         rnum = rnum + "" + b;

      }

   }

   if(rnum == "" || rnum == "-") {
      rnum = 0;
   }

   rnum = Number(rnum);

   return rnum;

}



function formatNumberDec(num, places, comma) {

var isNeg=0;

    if(num < 0) {
       num=num*-1;
       isNeg=1;
    }

    var myDecFact = 1;
    var myPlaces = 0;
    var myZeros = "";
    while(myPlaces < places) {
       myDecFact = myDecFact * 10;
       myPlaces = eval(myPlaces) + eval(1);
       myZeros = myZeros + "0";
    }
    
	onum=Math.round(num*myDecFact)/myDecFact;
		
	integer=Math.floor(onum);

	if (Math.ceil(onum) == integer) {
		decimal=myZeros;
	} else{
		decimal=Math.round((onum-integer)* myDecFact)
	}
	decimal=decimal.toString();
	if (decimal.length<places) {
        fillZeroes = places - decimal.length;
	   for (z=0;z<fillZeroes;z++) {
        decimal="0"+decimal;
        }
     }

   if(places > 0) {
      decimal = "." + decimal;
   }

   if(comma == 1) {
	integer=integer.toString();
	var tmpnum="";
	var tmpinteger="";
	var y=0;

	for (x=integer.length;x>0;x--) {
		tmpnum=tmpnum+integer.charAt(x-1);
		y=y+1;
		if (y==3 & x>1) {
			tmpnum=tmpnum+",";
			y=0;
		}
	}

	for (x=tmpnum.length;x>0;x--) {
		tmpinteger=tmpinteger+tmpnum.charAt(x-1);
	}


	finNum=tmpinteger+""+decimal;
   } else {
      finNum=integer+""+decimal;
   }

    if(isNeg == 1) {
       finNum = "-" + finNum;
    }

	return finNum;
}


function computeForm(form) {

if(form.moPmt.value.length == 0) {
   alert("Please the monthly payment amount you can afford.");
   form.moPmt.focus();
} else
if(form.intRate.value.length == 0) {
   alert("Please enter the loan's expected annual interest rate (enter zero for no-interest loans).");
   form.intRate.focus();
} else
if(form.months.value.length == 0) {
   alert("Please enter the term of the loan in months.");
   form.months.focus();
} else {

var VdownPay = stripNum(form.downPay.value);
var VmoPmt = stripNum(form.moPmt.value);
var VintRate = stripNum(form.intRate.value);
var Vmonths = stripNum(form.months.value);
var VtradeInVal = stripNum(form.tradeInVal.value);
var Vrebate = stripNum(form.rebate.value);

var VloanAmt = 0;
var VaffordCost = 0;

if(VintRate == 0) {

   VloanAmt = VmoPmt * Vmonths;
   form.loanAmt.value = "$" + formatNumberDec(VloanAmt,0,1);

   VaffordCost = eval(VloanAmt) + eval(VdownPay) + eval(VtradeInVal) + eval(Vrebate);
form.affordCost.value =  "$" + formatNumberDec(VaffordCost,0,1);

} else {

if(VintRate >= 1) {
   VintRate /= 100;
}
VintRate /= 12;

var pow = 1;

for (var j = 0; j < Vmonths; j++)
    pow = pow * (1 + VintRate);

VloanAmt = ((pow - 1) * VmoPmt) / (pow * VintRate);

form.loanAmt.value = "$" + formatNumberDec(VloanAmt,0,1);

VaffordCost = eval(VloanAmt) + eval(VdownPay) + eval(VtradeInVal) + eval(Vrebate);
form.affordCost.value =  "$" + formatNumberDec(VaffordCost,0,1);

}
}
}