Titanium FourSquare API Integration

fourSquareAPI.js

/*
Author: James Shrager (@jshrager)
Intended use: Appcelerator Titanium
Usage: http://www.LearningTitanium.com (@learningTi)
*/

var client_id = "YOUR_CLIENT_ID";
var client_secret = "YOUR_CLIENT_SECRET";
var redirectUri = 'http://YOUR_URL/foursquareCallback.php';
var ui = require('ui/ui');
var overlay = require('ui/overlayHUD');

/*
*	ONCE YOU HAVE AN ACTIVE TOKEN YOU CAN CALL THE API FROM WITHIN THE APP AS FOLLOWS:
*	var foursquare = require('services/fourSqAPI');
*	foursquare.callAPI("GET","venues/search", "ll="+lastCoords+"&limit=30&intent=checkin&radius=500, onSuccess_venues, onError);
*/

exports.callAPI = function(method, route, params, success, error)
{
            var xhr = Titanium.Network.createHTTPClient();

            xhr.open(method, "https://api.foursquare.com/v2/" + route + "?" + params + "&client_id=" + client_id+"&client_secret="+client_secret+"&v=20111208&oauth_token="+Ti.App.Properties.getString('foursquareToken'));
			
            xhr.onerror = function(e) {
                if ( error ) {
                	/* CALL THE ERROR FUNCTION PASSED IN */
					error(e);
				}
            };

            xhr.onload = function(_xhr) {
           		/* IF THERE IS A SUCCESS CALLBACK FUNCTION THEN CALL IT */
                if ( success ) {
					try{
						var response = JSON.parse(xhr.responseText);
						if(response.meta.code == 200)
						{
							/* CALL THE SUCCESS FUNCTION PASSED IN */
							success(response);
							response = null;
						}
						else
						{
							/* CALL THE ERROR FUNCTION PASSED IN */
							error();
						}
					}
					catch(e)
					{
						/* CALL THE ERROR FUNCTION PASSED IN */
						error();
					}

				}
            };

            xhr.send();
};

exports.authorize = function(_args) {

	var win, webView;

	function authorizeUICallback(e)
	{

		/*
		*	IF URL LOADED HAS #access_token THEN REDIRECT TO A SCRIPT TO CHECK IF USER IS REGISTERED
		*	SAVE ACCESS TOKEN TO LOCAL PROPERTY
		*	IF LOGIN OR REGISTER SCRIPT LOADED THEN USER SIGNUP / LOGIN FLOW IS COMPLETE:
		*		CLOSE WINDOW
		*		CLOSE NAV GROUP
		*		FIRE START APP FUNCTION IN CONTROLLER
		*/

	 if (e.url.indexOf('#access_token') != -1)
		 {
		    var token = e.url.split("=")[1];
		    
		    Ti.App.Properties.setString("foursquareToken",token);

			/* call a script with token in URL - check DB for token - if token exists then user exists - call login.php, if not call register.php */
			webView.url = "YOUR_URL.php?token="+token;

		} else if (e.url.indexOf('#error') != -1) {
			alert("We're sorry, something went wrong. Please try again.");
		   _args.navGroup.hide();
			_args.navGroup.close(win);
			_args.baseWindow.close();
		} else if(e.url.indexOf("register.php") != -1 || e.url.indexOf("login.php") != -1)
		{
			/* HAS AUTHORIZED */
			var userId = e.url.split("=")[1];
			Ti.App.Properties.setString('userId',userId);
			Ti.App.Properties.setBool("foursquareAuth", true);
			_args.navGroup.hide();
			_args.navGroup.close(win);
			_args.navGroup.close(_args.mainWind);
			_args.baseWindow.close();
			Ti.App.fireEvent("GLOBALLISTENER", {"TYPE": "startApp"});
		}
	}
	
	/*
	*	LOAD A WEBVIEW AND INITIALISE THE FOURSQUARE OUTH FLOW
	*	WHEN PAGES LOAD CHECK IF THEY ARE FROM YOUR URL OR FOURSQUARE - IF NOT THERE IS AN ERROR
	*	WHEN URL IS FOURSQUARECALLBACK THEN CALL AUTHORIZEUICALLBACK SCRIPT AND DISPLAY A LOADING INDICATOR

	*/

	function showAuthorizeUI(pUrl)
	{
	    win = Ti.UI.createWindow({
			modal:true,
			navBarHidden: false,
			barColor: '#c42026',
			title: null,
			backgroundColor: '#f1f1f1',
			barImage: 'images/navBar.png'
	    });
	    
	    webView = ui.webView({url: pUrl});
        //Ti.API.debug('Setting:[' + Ti.UI.AUTODETECT_NONE + ']');
        
        webView.addEventListener('load',
	        function(e) {
	            if (e.url.indexOf('http://YOUR_URL/') != -1 || e.url.indexOf('foursquare.com') != -1) {
	                Titanium.API.debug(e);
					 if (e.url.indexOf('foursquareCallback.php#') != -1 || e.url.indexOf('https://YOUR_URL/register.php') != -1 || e.url.indexOf('https://YOURURL/login.php') != -1)
					 {
						if (e.url.indexOf('foursquareCallback.php#') != -1)
						{
							overlay.load('Checking Details...').show(win);
						}
		                authorizeUICallback(e);
		            }
	            }
	            else
	            {
					alert("We're sorry, something went wrong. Please try again.");
					_args.navGroup.hide();
					_args.navGroup.close(win);
					_args.baseWindow.close();
	            }
	        });
        
	    win.add(webView);
	    _args.navGroup.open(win);
	}
	
	showAuthorizeUI(String.format('https://foursquare.com/oauth2/authenticate?response_type=token&client_id=%s&redirect_uri=%s',client_id,redirectUri));
}