var express = require('express');
var http = require('http');
var path = require('path');
var passport = require('passport');
var GoogleStrategy = require('passport-google-oauth').OAuth2Strategy;

var GOOGLE_CLIENT_ID = "xyz1234.apps.googleusercontent.com";
var GOOGLE_CLIENT_SECRET = "--google client secret";

// Serialized and deserialized methods when got from session
passport.serializeUser(function(user, done) {
    done(null, user);
});

passport.deserializeUser(function(user, done) {
    done(null, user);
});

// Define a middleware function to be used for every secured routes
var ensureAuthenticated = function(req, res, next){
  if (!req.isAuthenticated())
    res.send(401);
  else
  next();
};
//==================================================================

passport.use(new GoogleStrategy({
    clientID: GOOGLE_CLIENT_ID,
    clientSecret: GOOGLE_CLIENT_SECRET,
    callbackURL: "http://127.0.0.1:3000/auth/google/return"
  },
  function(accessToken, refreshToken, profile, done) {
    // asynchronous verification, for effect...
    process.nextTick(function () {

      // To keep the example simple, the user's Google profile is returned to
      // represent the logged-in user.  In a typical application, you would want
      // to associate the Google account with a user record in your database,
      // and return that user instead.
      return done(null, profile);
    });
  }
));



// Start express application
var app = express();

// all environments
app.set('port', process.env.PORT || 3000);
app.set('views', __dirname + '/views');
app.set('view engine', 'ejs');
app.use(express.favicon());
app.use(express.logger('dev'));
app.use(express.cookieParser()); 
app.use(express.bodyParser());
app.use(express.methodOverride());
app.use(express.session({ secret: 'securedsession' }));
app.use(passport.initialize()); // Add passport initialization
app.use(passport.session());    // Add passport initialization
app.use(app.router);
app.use(express.static(path.join(__dirname, 'public')));

// development only
if ('development' == app.get('env')) {
  app.use(express.errorHandler());
}

//==================================================================
// routes
app.get('/', function(req, res){
  res.render('index', { title: 'Express' });
});

app.get('/users', ensureAuthenticated, function(req, res){
  res.send([{name: "user1"}, {name: "user2"}]);
});
//==================================================================

//==================================================================
// route to test if the user is logged in or not
app.get('/loggedin', function(req, res) {
  res.send(req.isAuthenticated() ? req.user : '0');
});


//using "prompt" option in passport-google-oauth
app.get('/login-google',
  passport.authenticate('google', {prompt:'select_account', scope: ['https://www.googleapis.com/auth/userinfo.profile',
    'https://www.googleapis.com/auth/userinfo.email'] }),
  function(req, res){
    // The request will be redirected to Google for authentication, so this
    // function will not be called.
  });


app.get('/auth/google/return',
  passport.authenticate('google', { failureRedirect: '/#/loginfailure' }),
  function(req, res) {
    res.redirect('/');
  });

// route to log out
app.post('/logout', function(req, res){
  req.logOut();
  res.send(200);
});
//==================================================================

http.createServer(app).listen(app.get('port'), function(){
  console.log('Express server listening on port ' + app.get('port'));
});