var princ;
var ratepc;
var years;

function calcAmt(frm) {
	frm.pr.value = formatCurrency((Number(frm.saleprice.value) - Number(frm.deposit.value)) + Number(frm.warranty.value));
	
	princ = formatCurrency(frm.pr.value);
	ratepc = formatCurrency(frm.rt.value);
	years = formatCurrency(frm.yr.value);
	frm.amt.value = Math.round(princ*(Math.pow((1+ratepc/100),years))*100)/100;
	frm.intr.value = Math.round((princ*(Math.pow((1+ratepc/100),years))-princ)*100)/100;
	frm.repay.value = formatCurrency(Math.round(frm.amt.value / (years * 12)));
	frm.repayweek.value = formatCurrency(Math.round(frm.amt.value / (years * 52)));
}

function checkRate(frm) {
	if (ratepc == 0 || ratepc > 30) {
		window.alert("Make sure that the Interest Rate really is " +   ratepc +"%?")
	}
}

function checkTerm(frm) {
	if (years == 0 || years > 30) {
		window.alert("Make sure that the Term really is " + years + " years?")
	}
}

function formatCurrency(num) {
	num = num.toString().replace(/\$|\,/g,'');
	if(isNaN(num))
	num = "0";
	sign = (num == (num = Math.abs(num)));
	num = Math.floor(num*100+0.50000000001);
	cents = num%100;
	num = Math.floor(num/100).toString();
	if(cents<10)
	cents = "0" + cents;
	for (var i = 0; i < Math.floor((num.length-(1+i))/3); i++)
	num = num.substring(0,num.length-(4*i+3))+
	num.substring(num.length-(4*i+3));
	return (((sign)?'':'-') + num + '.' + cents);
}

var strTableBorder = "#0076AA"
var strTableColour = "#F4F4F4"
var strCellColour = "#F4F4F4"
var strFontFace = "Verdana"
var strFontSize = "8pt"
var strFontColour = "#000000"

document.write("<form method=\"GET\" name=\"frm\" onReset=\"frm.pr.focus()\">");
document.write("<input type=\"hidden\" name=\"intr\">")
document.write("<input type=\"hidden\" name=\"amt\">")
document.write("<table border=\"1\" bordercolor=\"" + strTableBorder + "\" bgcolor=\"" + strTableColour + "\" cellpadding=\"2\" cellspacing=\"0\">");
document.write("  <tr bordercolor=\"#0076AA\" bgcolor=\"#0076AA\">");
document.write("    <td colspan=2><p style=\"margin-top: 0px; margin-bottom: 0px; color: #FFFFFF\">Finance Calculator</p></td>");
document.write("  </tr>");

document.write("  <tr bordercolor=\"" + strCellColour + "\">");
document.write("    <td valign=\"top\">");

document.write("<table border=\"0\">");
document.write("  <tr bordercolor=\"" + strCellColour + "\">");
document.write("    <td nowrap align=\"right\"><p style=\"font-family: " + strFontFace + "; color: " + strFontColour + "; font-size: " + strFontSize + "\">Sale Price</p></td>");
document.write("    <td nowrap><p style=\"font-family: " + strFontFace + "; color: " + strFontColour + "; font-size: " + strFontSize + "\">$</p></td>");
document.write("    <td nowrap><input type=\"text\" name=\"saleprice\" value=\"29995.00\" size=\"10\" maxlength=\"10\" onChange=\"calcAmt(this.form)\"></td>");
document.write("  </tr>");
document.write("  <tr bordercolor=\"" + strCellColour + "\">");
document.write("    <td nowrap align=\"right\"><p style=\"font-family: " + strFontFace + "; color: " + strFontColour + "; font-size: " + strFontSize + "\">Deposit (eg. 15%)</p></td>");
document.write("    <td nowrap><p style=\"font-family: " + strFontFace + "; color: " + strFontColour + "; font-size: " + strFontSize + "\">$</p></td>");
document.write("    <td><input type=\"text\" name=\"deposit\" value=\"4499.25\" size=\"10\" maxlength=\"10\" onChange=\"calcAmt(this.form)\"></td>");
document.write("  </tr>");
document.write("  <tr bordercolor=\"" + strCellColour + "\">");
document.write("    <td nowrap align=\"right\"><p style=\"font-family: " + strFontFace + "; color: " + strFontColour + "; font-size: " + strFontSize + "\">Plus Warranty</p></td>");
document.write("    <td nowrap><p style=\"font-family: " + strFontFace + "; color: " + strFontColour + "; font-size: " + strFontSize + "\">$</p></td>");
document.write("    <td nowrap><input type=\"text\" name=\"warranty\" value=\"700.00\" size=\"10\" maxlength=\"10\" onChange=\"calcAmt(this.form)\"></td>");
document.write("  </tr>");
document.write("  <tr bordercolor=\"" + strCellColour + "\">");
document.write("    <td nowrap align=\"right\"><p style=\"font-family: " + strFontFace + "; color: " + strFontColour + "; font-size: " + strFontSize + "\">Loan amount</p></td>");
document.write("    <td nowrap><p style=\"font-family: " + strFontFace + "; color: " + strFontColour + "; font-size: " + strFontSize + "\">$</p></td>");
document.write("    <td nowrap><input type=\"text\" name=\"pr\" value=\"26195.75\" size=\"10\" maxlength=\"10\" onChange=\"calcAmt(this.form)\"></td>");
document.write("  </tr>");
document.write("</table>");

document.write("    </td>");
document.write("    <td valign=\"top\">");


document.write("<table border=\"0\">");
document.write("  <tr bordercolor=\"" + strCellColour + "\">");
document.write("    <td nowrap align=\"right\"><p style=\"font-family: " + strFontFace + "; color: " + strFontColour + "; font-size: " + strFontSize + "\">Interest Rate</p></td>");
document.write("    <td nowrap>&nbsp;</td>");
document.write("    <td nowrap><p style=\"font-family: " + strFontFace + "; color: " + strFontColour + "; font-size: " + strFontSize + "\"><input type=\"text\" name=\"rt\" value=\"14\" size=\"5\" maxlength=\"6\" onChange=\"calcAmt(this.form); checkRate(this.form)\">%</p></td>");
document.write("  </tr>");
document.write("  <tr bordercolor=\"" + strCellColour + "\">");
document.write("    <td nowrap align=\"right\"><p style=\"font-family: " + strFontFace + "; color: " + strFontColour + "; font-size: " + strFontSize + "\">Term (Years)</p></td>");
document.write("    <td nowrap>&nbsp;</td>");
document.write("    <td nowrap><input type=\"text\" name=\"yr\" value=\"4\" size=\"5\" maxlength=\"6\" onChange=\"calcAmt(this.form); checkTerm(this.form)\"></td>");
document.write("  </tr>");
document.write("  <tr bordercolor=\"" + strCellColour + "\">");
document.write("    <td nowrap align=\"right\"><p style=\"font-family: " + strFontFace + "; color: " + strFontColour + "; font-size: " + strFontSize + "\">Monthly</p></td>");
document.write("    <td nowrap><p style=\"font-family: " + strFontFace + "; color: " + strFontColour + "; font-size: " + strFontSize + "\">$</p></td>");
document.write("    <td nowrap><input type=\"text\" name=\"repay\" value=\"\" size=\"10\"></td>");
document.write("  </tr>");
document.write("  <tr bordercolor=\"" + strCellColour + "\">");
document.write("    <td nowrap align=\"right\"><p style=\"font-family: " + strFontFace + "; color: " + strFontColour + "; font-size: " + strFontSize + "\">Weekly</p></td>");
document.write("    <td nowrap><p style=\"font-family: " + strFontFace + "; color: " + strFontColour + "; font-size: " + strFontSize + "\">$</p></td>");
document.write("    <td nowrap><input type=\"text\" name=\"repayweek\" value=\"\" size=\"10\"></td>");
document.write("  </tr>");
document.write("  <tr bordercolor=\"" + strCellColour + "\">");
document.write("    <td nowrap><input type=\"reset\" name=\"clear\" value=\"Clear\" style=\"width: 75px\" class=\"button\"></td>");
document.write("    <td nowrap>&nbsp;</td>");
document.write("    <td nowrap align=\"right\"><input type=\"button\" name=\"calc\" value=\"Calculate\" size=\"10\" onClick=\"calcAmt(this.form)\" STYLE=\"width: 75px\" class=\"button\"></td>");
document.write("  </tr>");
document.write("</table>");

document.write("    </td>");
document.write("  </tr>");
document.write("</table>");

document.write("</form>");

calcAmt(frm);