// email address validation
function emailCheck(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					
}


// validate and submit form

function submitForm(form){
	
	//for each form element that has a class 'validate'
	
	var form = document.getElementById(form);
	
	for (var n=0; n < form.elements.length; n++) {
		
		if((form.elements[n].type == 'text') && (form.elements[n].className.match('validate'))){
			
			var field = form.elements[n];
	
			if ((field.value == null) || (field.value == '')){
				document.getElementById('fielderror').innerHTML = 'All mandatory fields marked * must be completed.';
				field.focus()
				return false
			}
			
			//check for valid email address
			if(form.elements[n].name == 'email'){
			
				if (emailCheck(field.value) == false){
					document.getElementById('fielderror').innerHTML = 'You must enter a valid email address.';
					field.focus()
					return false
				}
				
			}
			
		}
	}
		
	var params = "";
	
	//for each form element that is either a text, radio or textarea field add element name and value to params variable
	for (var n=0; n < form.elements.length; n++) {
		if(form.elements[n].type == 'text' || form.elements[n].type == 'textarea'){
			params = params + form.elements[n].name + '=' + form.elements[n].value + '&';
		}else if(form.elements[n].type == 'radio' && form.elements[n].checked){
			params = params + form.elements[n].name + '=' + form.elements[n].value + '&';
		}else if(form.elements[n].type == 'select-one'){
			params = params + form.elements[n].name + '=' + form.elements[n].options[form.elements[n].selectedIndex].text + '&';
		}
	}
	
	xmlHttp=getXmlHttpObject();
	
	var url='contact_send.php?'+params;
	
	xmlHttp.open('GET',url,true);
	
	xmlHttp.onreadystatechange = function()
		{ 
			if (xmlHttp.readyState==4)
			{
			document.getElementById('contact-form').innerHTML=xmlHttp.responseText;
			}
		}

	xmlHttp.send(null);
}