<?php

class Token extends Db_Model
{
    static $table_name = 'tokens';

    public static function generateToken($userId, $count = 0)
    {
        if ($count > 100) {
            new Exception('Зацикливание генерации токена');
        }

        $token = md5($userId . 'littleTanchu' . time() . 'salt' . rand(1000, 9999));

        $oldUser = self::findUser($token);

        if ($oldUser) {
            if ($oldUser == $userId) {
                self::prolongToken($token, $count++);
                return $token;
            } else {
                self::generateToken($userId);
            }
        } else {
            self::create(array(
                'user_id' => $userId,
                'token' => $token,
                'valid_until' => date('Y-m-d H:i:s', strtotime('+1 day'))
            ));

            return $token;
        }
    }

    public static function findUser($token)
    {
        return self::$db->select('user_id')->from(self::$table_name)
            ->where('token = ?', $token)
            ->where('valid_until > NOW()')
            ->fetchOne();
    }

    public static function getUserData($token)
    {
        return User::$db->select('u.id', 'u.email', 'u.level as role_id', 'u.name', 'u.lang')
            ->from(User::$table_name . ' u')
            ->join(self::$table_name . ' t', 't.user_id = u.id')
            ->where('t.valid_until > NOW()')
            ->where('t.token = ?', $token)
            ->fetchRow();
    }

    public static function prolongToken($token)
    {
        if (self::findUser($token)) {
            self::update(array(
                'valid_until' => date('Y-m-d H:i:s', strtotime('+1 day'))
            ), array(
                'token' => $token
            ));
        } else {
            return false;
        }
    }

    public static function destroyToken($token)
    {
        if (self::findUser($token)) {
            return self::delete(array(
                'token' => $token
            ));
        } else {
            return false;
        }
    }
}