function formValidation(){
	var firstName = document.getElementById('firstName');
	var lastName = document.getElementById('lastName');
	var address1 = document.getElementById('address1');
	var address2 = document.getElementById('address2');
	var city_county = document.getElementById('city_county');
	var postcode = document.getElementById('postcode').value;
	var tel_number = document.getElementById('tel_number').value;
	var email = document.getElementById('email');

	if(isAlphabet(firstName, "Please use only letters for your First Name")){
		if(isAlphabet(lastName, "Please use only letters for your Last Name")){
			if(isAlphanumeric(address1, "Please use only numbers and letters for Address1")){
				if(isAlphanumeric(address2, "Please use only numbers and letters for Address2")){
					if(isAlphabet(city_county, "Please use only letters for your city or county")){
						  if (isPostCode(postcode, "Postcode has invalid format")){							
							if(isUKTelephone(tel_number)){
								if(emailValidator(email, "Please enter a valid email address")){
										document.forms["stepForm2"].submit();
							}
						}
					}
				}
			}
		}
	
	}
}
	return false;	
	
}


//function to check newsletter signup form

function newsFormValidation(){
	var email_newsletter = document.getElementById('email_newsletter');

	if(emailValidator(email_newsletter, "Please enter a valid email")){
		submit_email(); }
	return false;
}


function notEmpty(elem, helperMsg){
	if(elem.value.length == 0){
		alert(helperMsg);
		elem.focus(); // set the focus to this input
		return false;
	}
	return true;
}

function isNumeric(elem, helperMsg){
	var numericExpression = /^[0-9]+$/;
	if(elem.value.match(numericExpression)){
		return true;
	}else{
		alert(helperMsg);
		elem.focus();
		return false;
	}
}

function isAlphabet(elem, helperMsg){
	var alphaExp = /^[ a-zA-Z]+$/;
	if(elem.value.match(alphaExp)){
		return true;
	}else{
		alert(helperMsg);
		elem.focus();
		return false;
	}
}

function isAlphanumeric(elem, helperMsg){
	var alphaExp = /^[ 0-9a-zA-Z]+$/;
	if(elem.value.match(alphaExp)){
		return true;
	}else{
		alert(helperMsg);
		elem.focus();
		return false;
	}
}

function emailValidator(elem, helperMsg){
	var emailExp = /^[\w\-\.\+]+\@[a-zA-Z0-9\.\-]+\.[a-zA-z0-9]{2,4}$/;
	if(elem.value.match(emailExp)){
		return true;
	}else{
		alert(helperMsg);
		elem.focus();
		return false;
	}
}

function isPostCode(elem, helperMsg) {

  // Permitted letters depend upon their position in the postcode.
  var alpha1 = "[abcdefghijklmnoprstuwyz]";                       // Character 1
  var alpha2 = "[abcdefghklmnopqrstuvwxy]";                       // Character 2
  var alpha3 = "[abcdefghjkpmnrstuvwxy]";                         // Character 3
  var alpha4 = "[abehmnprvwxy]";                                  // Character 4
  var alpha5 = "[abdefghjlnpqrstuwxyz]";                          // Character 5
  
  // Array holds the regular expressions for the valid postcodes
  var pcexp = new Array ();

  // Expression for postcodes: AN NAA, ANN NAA, AAN NAA, and AANN NAA
  pcexp.push (new RegExp ("^(" + alpha1 + "{1}" + alpha2 + "?[0-9]{1,2})(\\s*)([0-9]{1}" + alpha5 + "{2})$","i"));
  
  // Expression for postcodes: ANA NAA
  pcexp.push (new RegExp ("^(" + alpha1 + "{1}[0-9]{1}" + alpha3 + "{1})(\\s*)([0-9]{1}" + alpha5 + "{2})$","i"));

  // Expression for postcodes: AANA  NAA
  pcexp.push (new RegExp ("^(" + alpha1 + "{1}" + alpha2 + "{1}" + "?[0-9]{1}" + alpha4 +"{1})(\\s*)([0-9]{1}" + alpha5 + "{2})$","i"));
  
  // Exception for the special postcode GIR 0AA
  pcexp.push (/^(GIR)(\s*)(0AA)$/i);
  
  // Standard BFPO numbers
  pcexp.push (/^(bfpo)(\s*)([0-9]{1,4})$/i);
  
  // c/o BFPO numbers
  pcexp.push (/^(bfpo)(\s*)(c\/o\s*[0-9]{1,3})$/i);
  
  // Overseas Territories
  pcexp.push (/^([A-Z]{4})(\s*)(1ZZ)$/i);

  // Load up the string to check
  var postCode = elem;

  // Assume we're not going to find a valid postcode
  var valid = false;
  
  // Check the string against the types of post codes
  for ( var i=0; i<pcexp.length; i++) {
    if (pcexp[i].test(postCode)) {
    
      // The post code is valid - split the post code into component parts
      pcexp[i].exec(postCode);
      
      // Copy it back into the original string, converting it to uppercase and
      // inserting a space between the inward and outward codes
      postCode = RegExp.$1.toUpperCase() + " " + RegExp.$3.toUpperCase();
      
      // If it is a BFPO c/o type postcode, tidy up the "c/o" part
      postCode = postCode.replace (/C\/O\s*/,"c/o ");
      
      // Load new postcode back into the form element
      valid = true;
      
      // Remember that we have found that the code is valid and break from loop
      break;
    }
  }
  
  // Return with either the reformatted valid postcode or the original invalid 
  // postcode
  if (valid) {document.stepForm2.postcode.value=postCode; return true;} else {alert(helperMsg); document.stepForm2.postcode.focus(); return false;}
}


// Checks that a telephone number is valid and removes any spaces from input. BE SURE TO ADD '.value' TO GLOBAL VARIABLE DECLARATION!


function isUKTelephone(telephoneNumber) {

var telNumberErrorNo = 0;
var telNumberErrors = new Array ();
telNumberErrors[0] = "Valid UK telephone number";
telNumberErrors[1] = "Telephone number not provided";
telNumberErrors[2] = "UK telephone number without the country code, please";
telNumberErrors[3] = "UK telephone numbers should contain 10 or 11 numbers and no letters";
telNumberErrors[4] = "The telephone number should start with a 0";
telNumberErrors[5] = "The telephone number is either invalid or inappropriate";

  // Convert into a string and check that we were provided with something
  var telnum = telephoneNumber + " ";
  if (telnum.length <= 1)  
  {
     telNumberErrorNo = 1;
     alert (telNumberErrors[telNumberErrorNo]);
     document.stepForm2.tel_number.focus();     
     return false;   
  }

  telnum.length = telnum.length - 1;
  // Don't allow country codes to be included (assumes a leading "+")
  var exp = /^(\+)[\s]*(.*)$/;
  if (exp.test(telnum) == true) {
     telNumberErrorNo = 2;
     alert (telNumberErrors[telNumberErrorNo]);
     document.stepForm2.tel_number.focus();
     return false;
  }

  // Remove spaces from the telephone number to help validation
  while (telnum.indexOf(" ")!= -1)  {
    telnum = telnum.slice (0,telnum.indexOf(" ")) + telnum.slice (telnum.indexOf(" ")+1)
  }
  
  // Remove hyphens from the telephone number to help validation
  while (telnum.indexOf("-")!= -1)  {
    telnum = telnum.slice (0,telnum.indexOf("-")) + telnum.slice (telnum.indexOf("-")+1)
  }  
  
  // Now check that all the characters are digits
  exp = /^[0-9]{10,11}$/;
  if (exp.test(telnum) != true) {
     telNumberErrorNo = 3;
     alert (telNumberErrors[telNumberErrorNo]);
     document.stepForm2.tel_number.focus();
     return false;
  }
  
  // Now check that the first digit is 0
  exp = /^0[0-9]{9,10}$/;
  if (exp.test(telnum) != true) {
     telNumberErrorNo = 4;
     alert (telNumberErrors[telNumberErrorNo]);
     document.stepForm2.tel_number.focus();
     return false;
  }
	
	// Disallow numbers allocated for dramas.
	 
  // Array holds the regular expressions for the drama telephone numbers
  var tnexp = new Array ();
	tnexp.push (/^(0113|0114|0115|0116|0117|0118|0121|0131|0141|0151|0161)(4960)[0-9]{3}$/);
	tnexp.push (/^02079460[0-9]{3}$/);
	tnexp.push (/^01914980[0-9]{3}$/);
	tnexp.push (/^02890180[0-9]{3}$/);
	tnexp.push (/^02920180[0-9]{3}$/);
	tnexp.push (/^01632960[0-9]{3}$/);
	tnexp.push (/^07700900[0-9]{3}$/);
	tnexp.push (/^08081570[0-9]{3}$/);
	tnexp.push (/^09098790[0-9]{3}$/);
	tnexp.push (/^03069990[0-9]{3}$/);
	
	for (var i=0; i<tnexp.length; i++) {
    if ( tnexp[i].test(telnum) ) {
      telNumberErrorNo = 5;
      alert (telNumberErrors[telNumberErrorNo]);
      document.stepForm2.tel_number.focus();
      return false;
    }
	}
  
  // Finally check that the telephone number is appropriate.
  exp = (/^(01|02|03|05|070|071|072|073|074|075|07624|077|078|079)[0-9]+$/);
	if (exp.test(telnum) != true) {
     telNumberErrorNo = 5;
     alert (telNumberErrors[telNumberErrorNo]);
     document.stepForm2.tel_number.focus();
     return false;
  }

 // Telephone number seems to be valid - return the stripped telehone number  

  document.stepForm2.tel_number.value=telnum; return true;
}