<?php

/**
 * Checks if the SMTP connection configured through PHP.ini works as expected.
 *
 * Only checks socket connection with HELO command, not actually sending the email.
 */
class SMTPConnectCheck implements EnvironmentCheck
{
    /**
     * @var string
     */
    protected $host;

    /**
     * @var int
     */
    protected $port;

    /**
     * Timeout (in seconds).
     *
     * @var int
     */
    protected $timeout;

    /**
     * @param null|string $host
     * @param null|int $port
     * @param int $timeout
     */
    public function __construct($host = null, $port = null, $timeout = 15)
    {
        $this->host = ($host) ? $host : ini_get('SMTP');
        if (!$this->host) {
            $this->host = 'localhost';
        }
        
        $this->port = ($port) ? $port : ini_get('smtp_port');
        if (!$this->port) {
            $this->port = 25;
        }

        $this->timeout = $timeout;
    }

    /**
     * @inheritdoc
     *
     * @return array
     */
    public function check()
    {
        $f = @fsockopen($this->host, $this->port, $errno, $errstr, $this->timeout);
        if (!$f) {
            return array(
                EnvironmentCheck::ERROR,
                sprintf("Couldn't connect to SMTP on %s:%s (Error: %s %s)", $this->host, $this->port, $errno, $errstr)
            );
        }

        fwrite($f, "HELO its_me\r\n");
        $response = fread($f, 26);
        if (substr($response, 0, 3) != '220') {
            return array(
                EnvironmentCheck::ERROR,
                sprintf("Invalid mail server response: %s", $response)
            );
        }

        return array(EnvironmentCheck::OK, '');
    }
}