function startXMLHTTP()  {
	var xmlHttp;
		try {
			// Firefox, Opera 8.0+, Safari
			xmlHttp=new XMLHttpRequest();
		} catch (e){
			// Internet Explorer
			try {
				xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
			} catch (e) {
			  
			  try{
				xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
			   } catch (e) {
				alert("Your browser does not support AJAX!");
				return false;
			   }
		}
	}
	return xmlHttp;
}


function joinNewsletter() {
	
		
	if ( (!document.frm.fname.value) || (!document.frm.lname.value) || (!document.frm.email.value) ) {
		
		alert('Please fill in all fields \nfor newsletter registration');
	
	} else {
		
		var strFName = document.frm.fname.value;
		var strLName = document.frm.lname.value;
		var strEmail = document.frm.email.value;
		
		var appendTo = "?strFName="+strFName+"&strLName="+strLName+"&strEmail="+strEmail;
		
		
		var xmlHttp = startXMLHTTP();
		
		xmlHttp.onreadystatechange=function() {
    		if(xmlHttp.readyState==4) {
        		document.getElementById("signupOutput").innerHTML=xmlHttp.responseText;
        	}
		}
		
		xmlHttp.open("GET","assets/templates/terrasound/php_library/Ajax/newsletter_signup.php"+appendTo, true);
		xmlHttp.send(null);
		
	}
}

/* form validation snippets */

function isValid(reqFields) {
  
	var bStatus = true;
	for(i = 0; i < reqFields.length; i++) {
	
		var currentField = document.getElementById(reqFields[i]);
		
		// in case there was previous error, reset background color
		currentField.style.backgroundColor = '#FFFFFF';
		
		if(currentField.value == '') {
			
			// set background color to alert
			currentField.style.backgroundColor = '#CC9999';
			currentField.focus();
			bStatus = false;
			break;
		}
	}

  return bStatus;

} 



function isNumeric(sText) {
   var ValidChars = "0123456789.";
   var IsNumber=true;
   var Char;

 
   for (i = 0; i < sText.length && IsNumber == true; i++)  { 
      Char = sText.charAt(i); 
      if (ValidChars.indexOf(Char) == -1)  {
         IsNumber = false;
		 break;
      }
   }
   return IsNumber;
   
}



function checkContactForm() {
	
	var reqFields = new Array('txtTo','txtSubject','txtMessage', 'txtSenderName', 'txtSenderEmail');
		
	if (!isValid(reqFields)) {
		alert('All information required for submission');
		return false;
	} else {
		return true;
	}
}

function checkEmailSignup() {
	
	var reqFields = new Array('strFName','strLName','strEmail');
		
	if (!isValid(reqFields)) {
		alert('All information required for newsletter signup');
		return false;
	} else {
		return true;
	}
}