function isEmail(string) {
if (string.search(/^\w+((-\w+)|(\.\w+))*\@[A-Za-z0-9]+((\.|-)[A-Za-z0-9]+)*\.[A-Za-z0-9]+$/) != -1)
return true;
else
return false;
}


function jumpBox(list) {
   location.href = list.options[list.selectedIndex].value
   }

function checkNumber(input, min, max, msg)

{

   msg =  "Please enter a loan amount between 100 and 5000000, number of years between 1 and 25, and an interest rate between 1 and 99 percent" 





    var str = input.value;

    for (var i = 0; i < str.length; i++) {

        var ch = str.substring(i, i + 1)

        if ((ch < "0" || "9" < ch) && ch != '.') {

            alert(msg);

            return false;

        }

    }

    var num = 0 + str

    if (num < min || max < num) {

        alert(msg);

        return false;

    }

    input.value = str;

    return true;

}



function computeField(input)

{

    if (input.value != null && input.value.length != 0)

        input.value = "" + eval(input.value);

    computeForm(input.form);

}



function computeForm(form)

{

    if ((form.payments.value == null || form.payments.value.length == 0) ||

        (form.interest.value == null || form.interest.value.length == 0) ||

        (form.principal.value == null || form.principal.value.length == 0)) {

        return;

    }



    if (!checkNumber(form.payments, 1, 25, "No. of Years") ||

        !checkNumber(form.interest, .001, 99, "Interest") ||

        !checkNumber(form.principal, 100, 5000000, "Capital Value")) {

        form.payment.value = "error";
	
		form.payment4.value = "error";

        form.qau.value = "error";
	
		form.month.value = "error";

        return;

    }


  	var b = form.principal.value;



   var i = form.interest.value;

  if (i > 1.0) {

      i = i / 100.0;

     form.interest.value = i;

  }


 var c = i/4;

 i /= 12;
	

   var m = form.payments.value;
	
	m = m * 12;

    var pow = 1;

    for (var j = 0; j < m; j++)

        pow = pow * (1 + i);

    form.payment.value = (form.principal.value * pow * i) / (pow - 1);



		
		form.totalint.value = (form.payment.value * m)
    - form.principal.value

	form.payment.value = Math.round(form.payment.value);


   var q = form.payments.value;
	
	q = q * 4;

    var pow = 1;

    for (var j = 0; j < q; j++)

        pow = pow * (1 + c);

    form.payment4.value = (form.principal.value * pow * c) / (pow - 1);



		
		form.totalint.value = (form.payment4.value * q)
    - form.principal.value

	form.payment4.value = Math.round(form.payment4.value);

    form.qau.value = q;
    form.month.value = m;

}



function clearForm(form)

{

    form.payments.value = "";

    form.interest.value = "";

    form.principal.value = "";

}

function validate(form) {
//form.rawTrack.value = escape(document.location);
reg3 = /^[A-Za-z]{1,2}\d{1,2}[A-Za-z]? ?\d[A-Za-z]{2}$/; 
	if (form.title.value == "") {
        alert("Please enter your title");
		form.title.focus();
		return false;
    }
	if (form.firstName.value == "") {
        alert("Please enter your name");
		form.firstName.focus();
		return false;
    }
	if (form.secondName.value == "") {
        alert("Please enter your name");
		form.secondName.focus();
		return false;
    }
if (form.secondName.value.length > 25){
	alert("Your second name must be no longer than 25 characters");
		form.secondName.focus();
		return false;

}
	if (form.birthDay.value == "00") {
        alert("Please enter your Birth-day");
		form.birthDay.focus();
		return false;
    }
	if (form.birthMonth.value == "00") {
        alert("Please enter your Birth-month");
		form.birthMonth.focus();
		return false;
    }
	if (form.birthYear.value == "00") {
        alert("Please enter your Birth-year");
		form.birthYear.focus();
		return false;
    }

	if (form.houseNo.value == "") {
        alert("Please enter your house number or name");
		form.houseNo.focus();
		return false;
    }
	if (form.street.value == "") {
        alert("Please enter your street name");
		form.street.focus();
		return false;
    }
	if (form.town.value == "") {
        alert("Please enter your town/city name");
		form.town.focus();
		return false;
    }
	if (form.county.value == "") {
        alert("Plesae enter your county name");
		form.county.focus();
		return false;
    }
	if (form.postcode.value == "") {
        alert("Please enter your postcode");
		form.postcode.focus();
		return false;
    }
	if(!reg3.test(form.postcode.value))
	{
		alert("Please enter a valid postcode");
		form.postcode.focus();
		return false;
	}
	
	if (form.email.value == "" | !isEmail(form.email.value)) {
        alert("Please enter a valid email address");
		form.email.focus();
		return false;
    }
	if (form.contact.value == "" | form.contact.value.length < 10 | form.contact.value.length > 13) {
        	
		alert("Please enter a valid landline or mobile number including an area code");
		form.contact.focus();
		return false;
    }
	if (form.mobile.value== "" | form.mobile.value.length < 10 | form.mobile.value.length > 12) {
        	
		alert("Please enter a valid mobile or work number including an area code (we require 2 contact numbers)");
		form.contact.focus();
		return false;
    }
	if (form.value.value == "") {
        alert("Please enter value of the property");
		form.value.focus();
		return false;
    }
	if (form.purpose.value == 0) {
        alert("Please enter the purpose for the mortgage");
		form.purpose.focus();
		return false;
    	}
		
	if (form.mortgageTerm.value == 0) {
        alert("Please enter the Term of the mortgage");
		form.mortgageTerm.focus();
		return false;
    	}

	if (form.amount.value == "") {
        alert("Please enter the amount of mortgage you require");
		form.amount.focus();
		return false;
    	}
	if (form.startDay.value == 00) {
	    alert("Please enter the mortgage start-day");
		form.startDay.focus();
		return false;
    }
	if (form.startMonth.value == 00) {
        alert("Please enter the mortgage start-Month");
		form.startMonth.focus();
		return false;
    }
	if (form.startYear.value == 00) {
        alert("Please enter the mortgage start-Year");
		form.startYear.focus();
		return false;
    }
	if (form.selfCert.value == '') {
        alert("Please specify whether you are self-certified");
		form.selfCert.focus();
		return false;
    }

	
	LockButton(form,'big_submit');
    return true;
}