// JavaScript Document

//global variable for error flag
var errfound = false;

//function to validate by length
function ValidLength(item, len) {
   return (item.length >= len);
}

//function to validate an email address
function ValidEmail(item) {
   if (!ValidLength(item, 5)) return false;
   if (item.indexOf ('@', 0) == -1) return false;
   return true;
}

// display an error alert
function error(elem, text) {
// abort if we already found an error
   if (errfound) return;
   window.alert(text);
   elem.select();
   elem.focus();
   errfound = true;
}

// main validation function
function Validate() {
   var temp = "";
   var flag=0;
   temp="*** Please Enter The Following ***\n\n";
   errfound = false;
   if (!ValidLength(document.finance.principal.value,1))
   {
     temp = temp + "Please Enter Your Vehicle Loan Amount    \n";
	 flag=1;
   }
   if (flag==1)
     error(document.finance.principal, temp);
   
   return !errfound; /* true if there are no errors */
}

// main validation function
function Validate_Finance() {
   var temp = "";
   var flag=0;
   temp="*** Please Enter The Following ***\n\n";
   errfound = false;
   if (!ValidLength(document.financeapp.vehicle.value,1))
   {
     temp = temp + "Please Enter Your Type of Vehicle    \n";
	 flag=1;
   }
   if (!ValidLength(document.financeapp.name.value,1))
   {
     temp = temp + "Please Enter Your Name    \n";
	 flag=1;
   }
   if (!ValidLength(document.financeapp.phone.value,1))
   {
     temp = temp + "Please Enter Your Phone Number    \n";
	 flag=1;
   }
   if (flag==1)
     error(document.financeapp.vehicle, temp);
   
   return !errfound; /* true if there are no errors */
}

function calc_repayments (calc) {
  	var PB=calc.principal.value;
	if ((PB+0)!=0 && (calc.term.value+0)!=0) {
		//var I=8.95/4800;
		var I=14.89/4800;
		var S=0;	
		var n=calc.term.value;
		var OneplusItoTheN = Math.pow((1+I),n);
		var PMT=PB*(I*OneplusItoTheN/(OneplusItoTheN-1))*1/(1+(I*S));
			
		calc.repayments.value="$"+(Math.round(PMT*100)/100)
	} else {
		calc.repayments.value=""
	}
	calc.loanpayments.value = calc.repayments.value
	calc.loanterm.value = calc.term.value / 4
}