// Create an object to handle our AJAX.
function AJAX(){
	var objSelf = this;
 
	// This struct will cache the current XmlHTTP requests
	// so that we can reference them if a call fails.
	this.CurrentRequests = {};
}
 
 
// This handles the JSON request. This checks to see if the current
// request is already being processed and also handles any error
// wiring that is required.
AJAX.prototype.GetJSON = function( $1, $2, $3, $4 ){
	var objSelf = this;
	var strName = $1;
	var strURL = $2;
	var objOptions = $3;
	var fnCallback = $4;
 
	// Check to see if there are only three arguments. If there
	// are only 3, then the first one (name of request) which is
	// optional was not passed in. Shift the other arguments
	// to the appropriate variables.
	if (arguments.length == 3){
 
		// Name is not being used.
		strName = null;
		strURL = $1;
		objOptions = $2;
		fnCallback = $3;
 
	}
 
	// First, we have to check to see if this request is
	// already being processed. We don't want the user to
	// try and fire off multiple requests of the same type.
	// Of course, if the name is NULL, then don't worry.
	if (!strName || !this.CurrentRequests[ strName ]){
 
		// Store current request.
		this.CurrentRequests[ strName ] = true;
 
		// Make actual AJAX request.
		$.ajax(
			{
				// Basic JSON properties.
				url: strURL,
				data: objOptions,
				dataType: "json",
 
				// The success call back.
				success: function( objResponse ){
					// Remove request flag.
					objSelf.CurrentRequests[ strName ] = false;
 
					// Pass off to success handler.
					fnCallback( objResponse );
				},
 
				// The error handler.
				error: function( objRequest ){
					// Remove request flag.
					objSelf.CurrentRequests[ strName ] = false;
 
					// Pass off to fail handler.
					objSelf.AJAXFailHandler(
						objRequest,
						fnCallback
						);
				}
			}
			);
 
	} else {
 
		// This request is currently being processed.
		alert( "Request being processed. Be patient." );
 
	}
}
 
 
// This will handle all AJAX failures.
AJAX.prototype.AJAXFailHandler = function( objRequest, fnCallback ){
	// Since this AJAX request failed, let's call the callback
	// but manually create a failure response.
	fnCallback(
		{
			SUCCESS: false,
			DATA: "",
			ERRORS: [ "Request failed" ]
		}
		);
}