// Registeration Page Validation:
var messageElementId = 'message';
	function getElement (elementId){
		return (document.getElementById)? document.getElementById(elementId) : document.all[elementId];
	}
	
	function showHideElement(oElement, show){
		oElement.style.display = (show)? 'block' : 'none';
	}
	
	function disableElement(oElement, disable){
		oElement.disabled = (disable)? true : false;
	}
	
	function findElementPosition( oElement ) {

		if( typeof( oElement.offsetParent ) != 'undefined' ) {
		    for( var posX = 0, posY = 0; oElement; oElement = oElement.offsetParent ) {
		      posX += oElement.offsetLeft;
		      posY += oElement.offsetTop;
		    }
		    return [ posX, posY ];
		  } else {
		    return [ oElement.x, oElement.y ];
		  }
	}

	function getElementDimensions( oElement ) {
		return [ oElement.offsetWidth, oElement.offsetHeight ];
	}	
	
	function setElementPosition(oElement, offsetLeft, offsetTop) {

		oElement.style.left = offsetLeft + 'px';
		oElement.style.top = offsetTop + 'px';
	}
	
	function showMessage(elementId, message, type){
		
		messageElement = getElement(elementId + '_' + messageElementId);
		messageElement.innerHTML = message;
		messageElement.className = (type == 'Error')? 'error': 'success';
		showHideElement(messageElement, true);

		//oElement = getElement(elementId);
		//oElementPosition = findElementPosition(oElement);
		//oElementDimension = getElementDimensions(oElement);
		//setElementPosition(oElement, oElementPosition[0] + oElementDimension[0], oElementPosition[1] + oElementDimension[1]); 
	}
	
	function validateField(oField, message, condition){
		if(condition){
			showMessage (oField.id, message, 'Error');
			oField.select();
			oField.focus();
			disableElement(getElement('send'), true);
			return false;
		}
		showHideElement(getElement(oField.id + '_' + messageElementId), false);
		disableElement(getElement('send'), false);
		return true;
	}
	
	function validateForm(oForm){
		if(oForm.user_name.value == ''){
			return validateField (oForm.user_name, 'Please enter your user name', (oForm.user_name.value == ''));
		}else if(oForm.password.value == ''){
			return validateField (oForm.password, 'Please enter your password', (oForm.password.value == ''));
		}else if(oForm.confirm_password.value == ''){
			return validateField (oForm.confirm_password, 'Please confirm your password', (oForm.confirm_password.value == ''));
		}else if(oForm.confirm_password.value != oForm.password.value){
			return validateField (oForm.confirm_password, 'Password mismatch', (oForm.confirm_password.value != oForm.password.value));
		}else if(oForm.clinic_name.value == ''){
			return validateField (oForm.clinic_name, 'Please enter your clinic name', (oForm.clinic_name.value == ''));
		}else if(oForm.phone.value == ''){
			return validateField (oForm.phone, 'Please enter your phone number', (oForm.phone.value == ''));
		}else if(oForm.fax.value == ''){
			return validateField (oForm.fax, 'Please enter your fax number', (oForm.fax.value == ''));
		}else if(oForm.post_code.value == ''){
			return validateField (oForm.post_code, 'Please enter your P.O Box number', (oForm.post_code.value == ''));
		}else if(oForm.email.value == ''){
			return validateField (oForm.email, 'Please enter your email', (oForm.email.value == ''));
		}else if(oForm.city.value == ''){
			return validateField (oForm.city, 'Please enter your city', (oForm.city.value == ''));
		}else if(oForm.address.value == ''){
			return validateField (oForm.address, 'Please enter your address', (oForm.address.value == ''));
		}else if(oForm.manager_name.value == ''){
			return validateField (oForm.manager_name, 'Please enter manager name', (oForm.manager_name.value == ''));
		}else if(oForm.security_code.value == ''){
			return validateField (oForm.security_code, 'Please enter security code', (oForm.security_code.value == ''));
		}
		//showHideElement(messageElement, false);
		disableElement(getElement('send'), false);
		return true;
	}
	
	function checkUsername(userName){
		xmlHttp=GetXmlHttpObject()
		if (xmlHttp==null){
		 alert ("Browser does not support HTTP Request")
		 return
		}
	
		xmlHttp.onreadystatechange=function(){ 
	
		 if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete"){
			 userNameMessage = getElement("user_name_message");
			 showMessage('user_name', xmlHttp.responseText, (xmlHttp.responseText.indexOf('Invalid') == 0)? 'Error' : 'success');
			 disableElement(getElement('send'), (xmlHttp.responseText.indexOf('Invalid') == 0));
			 
		 } 
	  }  	
		xmlHttp.open("GET", "check_members.ajax.php?user_name="+userName, true)
		xmlHttp.send(null)
	}
	
	function GetXmlHttpObject(){ 
		var objXMLHttp=null
		if (window.XMLHttpRequest){
			objXMLHttp=new XMLHttpRequest()
		 }else if (window.ActiveXObject){
			objXMLHttp=new ActiveXObject("Microsoft.XMLHTTP")
		 }
		return objXMLHttp
	}