function submission()
{
    var a = document.getElementById("form_forename");
    var b = document.getElementById("form_surname");
    var c = document.getElementById("form_from_email");
    var d = c.value.indexOf("@");
    var e = document.getElementById("form_comments");
    
    
    if(a.value == "")
    {
        alert("Please enter your forename");
        a.focus();
        return false;
    }
    if(b.value == "")
    {
        alert("Please enter your Surname");
        b.focus();
        return false;
    }
      
    if(!echeck(c.value))
    {
        alert("Please enter a valid Email Address");
        c.focus();
        return false;
    }   
    
    if (e.value == "")
    {   
        alert("Please enter your Comments");
        e.focus();
        return false;
    } 
    
    var answer = document.getElementById("answer");
    
    if(answer != null)
    {
        if(answer.value == "")
        {
            alert("You must answer the verification question");
            answer.focus();
            return false;
        } 
       
        var ajaxRequest;  // The variable that makes Ajax possible!
	
	   try
	   {
		  // Opera 8.0+, Firefox, Safari
		  ajaxRequest = new XMLHttpRequest();
	   } 
	   catch (e)
	   {
		  // Internet Explorer Browsers
		  try
		  {		  
			 ajaxRequest = new ActiveXObject("Msxml2.XMLHTTP");
		  } 
		  catch (e) 
		  {
			 try
			 {
        	    ajaxRequest = new ActiveXObject("Microsoft.XMLHTTP");
    	     } 
    	     catch (e)
    	     {
				    // Something went wrong
				    alert("Your browser broke!");
				return false;
			 }
		  }
       }
	 
	   ajaxRequest.onreadystatechange = function()
	   {
            if(ajaxRequest.readyState == 4)
            {
                if(ajaxRequest.responseText == "match")
                { 
                    var a = document.forms["contact_form"].elements["form_contact_form"];
                    a.value = "Submit";
                    document.forms["contact_form"].submit();
                    return;
                }
                else
                    if(ajaxRequest.responseText == null)
                    {
                        document.getElementById("captcha").innerHTML = "<div id=\"captcha_title\">System Error</div> <div class=\"captcha_text\">We are currently having technical problems with our submissions system.<br/> We are trying to resolve the problem as quickly as possible. <br/>Please attempt submission at another time</div>";
                        return;
                    }
                    else
                    {
                        alert("You did not answer the question correctly! Try again.");
                        document.getElementById("captcha").innerHTML = ajaxRequest.responseText;
                        var answer = document.getElementById("answer").focus();
                        return;
                    }                
		    }
	   }
	   
	   var number = document.getElementById("captcha_number").value;
	
	   ajaxRequest.open("GET", "/includes/ajax/add_listing_submission_form_ajax.php?number=" + number + "&answer=" + answer.value, true);
	   ajaxRequest.send(null);        
    }
    
    return false;
       
}


function echeck(str) 
{
		var at="@";
		var dot=".";
		var lat=str.indexOf(at);
		var lstr=str.length;
		var ldot=str.indexOf(dot);
		if (str.indexOf(at)==-1)
		{
		   return false;
		}

		if (str.indexOf(at)==-1 || str.indexOf(at)==0 || str.indexOf(at)==lstr)
		{
		   return false;
		}

		if (str.indexOf(dot)==-1 || str.indexOf(dot)==0 || str.indexOf(dot)==lstr)
		{
		    return false;
		}

		 if (str.indexOf(at,(lat+1))!=-1)
		 {
		    return false;
		 }

		 if (str.substring(lat-1,lat)==dot || str.substring(lat+1,lat+2)==dot)
		 {
		    return false;
		 }

		 if (str.indexOf(dot,(lat+2))==-1)
		 {
		    return false
		 }
		
		 if (str.indexOf(" ")!=-1)
		 {
		    return false;
		 }

    return true;					
}