<?php

/*
 * This file is part of SwiftMailer.
 * (c) 2004-2009 Chris Corbyn
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

/**
 * Wraps an IoBuffer to send/receive SMTP commands/responses.
 *
 * @author Chris Corbyn
 */
interface Swift_Transport_SmtpAgent
{
    /**
     * Get the IoBuffer where read/writes are occurring.
     *
     * @return Swift_Transport_IoBuffer
     */
    public function getBuffer();

    /**
     * Run a command against the buffer, expecting the given response codes.
     *
     * If no response codes are given, the response will not be validated.
     * If codes are given, an exception will be thrown on an invalid response.
     *
     * @param string   $command
     * @param int[]    $codes
     * @param string[] $failures An array of failures by-reference
     */
    public function executeCommand($command, $codes = [], &$failures = null);
}