public function init( $config = NULL )
    {
        $this->mailer = new PHPMailer();

        foreach ( $config as $key => $value )
        {
            switch ( $key )
            {
                case 'from_email':
                    $this->mailer->From = $value;
                    break;

                case 'from_name':
                    $this->mailer->FromName = $value;
                    break;

                case 'is_html':
                    $this->mailer->isHTML( ( bool ) $value );
                    break;

                case 'smtp':
                    if ( !empty( $value ) )
                    {
                        // mark it as SMTP mail
                        $this->mailer->isSMTP();

                        $this->mailer->Host       = $value[ 'host' ];
                        $this->mailer->SMTPAuth   = $value[ 'auth' ];
                        $this->mailer->Username   = $value[ 'username' ];
                        $this->mailer->Password   = $value[ 'password' ];
                        $this->mailer->SMTPSecure = $value[ 'security' ];
                        $this->mailer->Port       = $value[ 'port' ];
                    }
                    break;

                case 'reply_to':
                    if ( !empty( $value ) )
                    {
                        $this->mailer->addReplyTo( $value[ 'email' ], $value[ 'name' ] );
                    }
                    break;

                default:
                    // do nothing
                    break;
            }
        }
    }