blue-twilight/app/Http/Controllers/Auth/LoginController.php

<?php

namespace App\Http\Controllers\Auth;

use App\Facade\Theme;
use App\Facade\UserConfig;
use App\Http\Controllers\Controller;
use App\User;
use Illuminate\Foundation\Auth\AuthenticatesUsers;
use Illuminate\Http\Request;
use Laravel\Socialite\Two\FacebookProvider;
use Socialite;

class LoginController extends Controller
{
    /*
    |--------------------------------------------------------------------------
    | Login Controller
    |--------------------------------------------------------------------------
    |
    | This controller handles authenticating users for the application and
    | redirecting them to your home screen. The controller uses a trait
    | to conveniently provide its functionality to your applications.
    |
    */

    use AuthenticatesUsers;

    /**
     * Where to redirect users after login / registration.
     *
     * @var string
     */
    protected $redirectTo = '/';

    /**
     * Create a new controller instance.
     *
     * @return void
     */
    public function __construct()
    {
        $this->middleware('guest', ['except' => 'logout']);
    }

    protected function credentials(Request $request)
    {
        $result = $request->only($this->username(), 'password');

        // Only allow activated users to login
        $result['is_activated'] = true;

        return $result;
    }

    /**
     * Show the application's login form.
     *
     * @return \Illuminate\Http\Response
     */
    public function showLoginForm(Request $request)
    {
        return Theme::render('auth.v2_unified', [
            'active_tab' => 'login',
            'info' => $request->session()->get('info')
        ]);
    }

    /**
     * Redirect the user to the Facebook authentication page.
     *
     * @return \Illuminate\Http\Response
     */
    public function redirectToFacebook()
    {
        $socialite = $this->setSocialiteConfigs();
        return $socialite->driver('facebook')->redirect();
    }

    /**
     * Obtain the user information from Facebook.
     *
     * @return \Illuminate\Http\Response
     */
    public function handleFacebookCallback(Request $request)
    {
        $socialite = $this->setSocialiteConfigs();
        $facebookUser = $socialite->driver('facebook')->user();
        $user = User::where('facebook_id', $facebookUser->id)->first();

        if (is_null($user))
        {
            $request->getSession()->put('registerData', [
                'name' => $facebookUser->name,
                'email' => $facebookUser->email,
                'facebook_id' => $facebookUser->id,
                'is_activated' => true
            ]);

            return redirect(route('register'));
        }

        $this->guard()->login($user);

        return redirect(route('home'));
    }

    private function setSocialiteConfigs()
    {
        // Force Socialite to use our config from the database instead of hard-coded in config/services.php
        $socialite = app()->make('Laravel\Socialite\Contracts\Factory');
        $socialite->extend(
            'facebook',
            function ($app) use ($socialite) {
                $config = [
                    'client_id' => UserConfig::get('facebook_app_id'),
                    'client_secret' => decrypt(UserConfig::get('facebook_app_secret')),
                    'redirect' => route('login_callback.facebook')
                ];
                return $socialite->buildProvider(FacebookProvider::class, $config);
            }
        );

        return $socialite;
    }
}