invoiceninja/app/Libraries/OAuth.php

<?php
/**
 * Invoice Ninja (https://invoiceninja.com)
 *
 * @link https://github.com/invoiceninja/invoiceninja source repository
 *
 * @copyright Copyright (c) 2019. Invoice Ninja LLC (https://invoiceninja.com)
 *
 * @license https://opensource.org/licenses/AAL
 */

namespace App\Libraries;

use App\Models\User;
use Illuminate\Support\Facades\Session;
use Laravel\Socialite\Facades\Socialite;

/**
 * Class OAuth
 * @package App\Libraries
 */
class OAuth
{

    protected $provider_instance;

    protected $provider_id;

    /**
     * Socialite Providers
     */
    const SOCIAL_GOOGLE = 1;
    const SOCIAL_FACEBOOK = 2;
    const SOCIAL_GITHUB = 3;
    const SOCIAL_LINKEDIN = 4;
    const SOCIAL_TWITTER = 5;
    const SOCIAL_BITBUCKET = 6;

    /**
     * @param Socialite $user
     */

    public static function handleAuth(object $user, string $provider)
    {
        /** 1. Ensure user arrives on the correct provider **/

        $query = [
            'oauth_user_id' =>$user->getId(),
            'oauth_provider_id'=>$provider
        ];

        if($user = MultiDB::hasUser($query))
        {
            return $user;
        }
        else
            return false;

    }

    /* Splits a socialite user name into first and last names */
    public static function splitName($name)
    {
        $name = trim($name);
        $last_name = (strpos($name, ' ') === false) ? '' : preg_replace('#.*\s([\w-]*)$#', '$1', $name);
        $first_name = trim(preg_replace('#' . preg_quote($last_name, '/') . '#', '', $name));

        return [$first_name, $last_name];
    }

    public static function providerToString(int $social_provider) : string
    {
        switch ($social_provider)
        {
            case SOCIAL_GOOGLE:
                return 'google';
            case SOCIAL_FACEBOOK:
                return 'facebook';
            case SOCIAL_GITHUB:
                return 'github';
            case SOCIAL_LINKEDIN:
                return 'linkedin';
            case SOCIAL_TWITTER:
                return 'twitter';
            case SOCIAL_BITBUCKET:
                return 'bitbucket';
        }
    }

    public static function providerToInt(string $social_provider) : int
    {
        switch ($social_provider)
        {
            case 'google':
                return SOCIAL_GOOGLE;
            case 'facebook':
                return SOCIAL_FACEBOOK;
            case 'github':
                return SOCIAL_GITHUB;
            case 'linkedin':
                return SOCIAL_LINKEDIN;
            case 'twitter':
                return SOCIAL_TWITTER;
            case 'bitbucket':
                return SOCIAL_BITBUCKET;
        }
    }

    public function getProvider($provider)
    {
        switch ($provider)
        {
            case 'google';
                $this->provider_instance = new Providers\Google();
                $this->provider_id = self::SOCIAL_GOOGLE;
                return $this;

            default:
                return null;
                break;
        }
    }

    public function getTokenResponse($token)
    {
        $user = false;

        $payload = $this->provider_instance->getTokenResponse($token);

        $oauth_user_id = $this->provider_instance->harvestSubField($payload);

         $query = [
            'oauth_user_id' => oauth_user_id,
            'oauth_provider_id'=> $this->provider_id
        ];

        if($user = MultiDB::hasUser($query))
        {
            return $user;
        }
        else
            return false;

    }
}