/******************* form field validation ********************/
/*********** Martin Works Inc. http://martinworks.com *********/

/********* color for cell good and bad ***********/
var goodcolor='#ffffff';
var errcolor='#ffff00';


function validateEmpty(fieldname) {
    var error = "";

    if (fieldname.value.length == 0) {
        fieldname.style.background = errcolor;
        error = "The required field " + fieldname.name + " has not been filled in.\n"
    } else {
        fieldname.style.background = goodcolor;
    }
    return error;
}

function trim(s)
{
  return s.replace(/^\s+|\s+$/, '');
}

function validateEmail(fieldname) {
    var error="";
    var tfieldname = trim(fieldname.value);                        // value of field with whitespace trimmed off
    var emailFilter = /^[^@]+@[^@.]+\.[^@]*\w\w$/ ;
    var illegalChars= /[\(\)\<\>\,\;\:\\\"\[\]]/ ;

    if (fieldname.value == "") {
        fieldname.style.background = errcolor;
        error = "You didn't enter an email address.\n";
    } else if (!emailFilter.test(tfieldname)) {              //test email for illegal characters
        fieldname.style.background = errcolor;
        error = "Please enter a valid email address.\n";
    } else if (fieldname.value.match(illegalChars)) {
        fieldname.style.background = errcolor;
        error = "The email address contains illegal characters.\n";
    } else {
        fieldname.style.background = goodcolor;
    }
    return error;
}

function validatePhone(fieldname) {
    var error = "";
    var stripped = fieldname.value.replace(/[\(\)\.\-\Xx ]/g, '');

   if (fieldname.value == "") {
        error = "You didn't enter a phone number.\n";
        fieldname.style.background = errcolor;
    } else if (isNaN(parseInt(stripped))) {
        error = "The phone number contains illegal characters.\n";
        fieldname.style.background = errcolor;
    } else if (!(stripped.length >= 10)) {
        error = "The phone number is the wrong length. Make sure you included an area code.\n";
        fieldname.style.background = errcolor;
    } else {
        fieldname.style.background = goodcolor;
    }
    return error;
}

function validateForm(formName) {
var reason = "";
  reason += validateEmail(formName.email);
  reason += validatePhone(formName.phone);
  reason += validateEmpty(formName.product);
  reason += validateEmpty(formName.name);
  reason += validateEmpty(formName.address);

  if (reason != "") {
    alert("Some fields need correction:\n" + reason);
    return false;
  }
  return true;
}