// JavaScript Document

function DoSubmit()

{

    if (!Validate())

    {

        // Not validated

        BlankFields();

    }

    else

    {

        // Calculate

        Calculate();

    }

}

 

function BlankFields()

{

    document.getElementById("RFC").innerHTML = " ";

    document.getElementById("SAV").innerHTML = " ";

    document.getElementById("TOT").innerHTML = " ";

}

 

function Calculate()

{

    var mpy = document.nitro.MilesDrivenPerYear.value;

    var agp = document.nitro.AverageGasPrice.value;

    var mpg = document.nitro.MPG.value;

    var tir = document.nitro.CostToReplaceTire.value;

    

    var amt = ((agp / mpg) * mpy) * .04; //.035;

    var sav = tir * .44444;

    var tot = sav + amt;

    

    //RFC, SAV, TOT

    document.getElementById("RFC").innerHTML = " " + toCash(amt*100, '$', ',') ;

    document.getElementById("SAV").innerHTML = " " + toCash(sav*100,"$",",",".") ;

    document.getElementById("TOT").innerHTML = " " + toCash(tot*100,"$",",",".") ;
	
    document.getElementById("result").style.display="";
	
	document.getElementById("calc").style.display="none";

}

 
 function DoReturn() {

    document.getElementById("calc").style.display="";

	document.getElementById("result").style.display="none";
	
	document.getElementById("mpg").value="";
}
 
 

function Validate()

{

    if (document.nitro.MilesDrivenPerYear.value =="" || (!isNumeric(document.nitro.MilesDrivenPerYear.value)))

            {

                alert("Please enter a number for Miles Driven Per year!")

                return false;

            }

            if (document.nitro.CostToReplaceTire.value =="" || (!isNumeric(document.nitro.CostToReplaceTire.value)))

            {

                alert("Please enter a number for Cost to Replace Tire!")

                return false;

            }

            if (document.nitro.AverageGasPrice.value =="" || (!isNumeric(document.nitro.AverageGasPrice.value)))

            {

                alert("Please enter a number for Average Gas Price!")

                return false;

            }

            if (document.nitro.MPG.value =="" || (!isNumeric(document.nitro.MPG.value)))

            {

                alert("Please enter a number for MPG!")

                return false;

            }

            if (document.nitro.MPG.value<1)

            {

                alert("Please enter a number greater than 1 for MPG!")

                return false;

            }

 

            return true;            

}


// Validation Routines //

function isNumeric(str) {

            return str.match(/^[ ]*[+-]?\d*\.?\d+[ ]*$/);

} 

// Formatting Routines // 

function toCash(p, c, t, d) {

  var s = (0 > p) ? '-' : ''

  var m = String(Math.round(Math.abs(p)))

  var j, k = '', f

  c = c || '' ; t = t || '' ; d = d || '.'

 

  while (m.length < 3) m = '0' + m

  f = m.substring((j = m.length - 2))

  while (j > 3) { k = t + m.substring(j - 3, j) + k ; j -= 3 }

  k = m.substring(0, j) + k

  return s + c + k + d + f }