abstract class AbstractSQLBase {

    const DRIVER = 'mysql';

    protected $pdo;

    public function __construct() {
        $dsn = self::DRIVER.':host='.Config::SQL_HOST.';port='.Config::SQL_PORT.';dbname='.Config::SQL_DATABASE_NAME;
        try {
            $this->pdo = new PDO($dsn, Config::SQL_USER, Config::SQL_PASSWORD);
            $this->pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
        } catch (PDOException $e) {
            print "Erreur SQL : " . $e->getMessage() . "<br/>";
            die();
        }
    }

}

class UserManager extends AbstractSQLBase {

    private function hashPassword($password) {
        return md5('sa'.$password.'lt');
    }

    public function authenticate($username, $password) {
        $query = $this->pdo->prepare("SELECT id, first_name, last_name, email, username, password, avatar_path, is_admin FROM users WHERE username=:user");
        $query->bindValue(':user',$username);
        $query->execute();

        $result = $query->fetch(PDO::FETCH_OBJ);

        if($result && $result->password == $this->hashPassword($password) ) {
            return new User($result->id, $result->first_name,$result->last_name,$result->email,$result->username,$result->avatar_path,$result->is_admin);
        } else {
            throw new UserNotFoundException('Login incorrect');
        }
    }

    private function getUserByParam($param_id,$param_value,$error) {
        $query = $this->pdo->prepare("SELECT id, first_name, last_name, email, username, password, avatar_path, is_admin FROM users WHERE ".$param_id."=:param");
        $query->bindValue(':param',$param_value);
        $query->execute();

        $result = $query->fetch(PDO::FETCH_OBJ);
        if($result) {
            return new User($result->id, $result->first_name,$result->last_name,$result->email,$result->username,$result->avatar_path,$result->is_admin);
        } else {
            throw new UserNotFoundException($error);
        }
    }

    public function getUserById($id) {
        return $this->getUserByParam("id",$id,'ID introuvable');
    }

    public function getUserByUsername($username) {
        return $this->getUserByParam("username",$username,'Username introuvable');
    }

    public function getUserByEmail($email) {
        return $this->getUserByParam("email",$email,'Email introuvable');
    }

    public function register(User $user, $password) {
        $query = $this->pdo->prepare("INSERT INTO users (first_name, last_name, email, username, password, avatar_path, is_admin) VALUES (:first_name, :last_name, :email, :username, :password, :avatar_path, 0)");
        $query->bindValue(':first_name', $user->getFirst_name());
        $query->bindValue(':last_name', $user->getLast_name());
        $query->bindValue(':email', $user->getEmail());
        $query->bindValue(':username', $user->getUsername());
        $query->bindValue(':password', $this->hashPassword($password));
        $query->bindValue(':avatar_path', $user->getAvatar_path());
        return $query->execute();
    }
}