<?php

class Qs_Job
{
    const ERROR_CONNECTION_FAILED = 1;
    const ERROR_WRITE_SOCKET      = 2;

    protected static $_ip;
    protected static $_port;
    protected static $_timeout;
    protected static $_config;

    /**
     * Directly run job using wget
     *
     * @static
     *
     * @param string $url
     * @param null|string   $token
     */
    public static function run($url, $token = null)
    {
        $url = Qs_Auth::addAuthCredentials($url);
        $tries = 1;
        $timeout = 60;
        $extra = array();

        if ($token) {
            $extra[] = '--header=' . escapeshellarg('X-Job-Token: ' . $token);
        }

        $cmd = 'wget -q '
            . ' --tries=' . $tries
            . ($timeout ? ' --timeout=' . $timeout : '')
            . ($extra ? ' '. implode(' ', $extra) : '')
            . ' -O-'
            . ' ' . escapeshellarg($url)
            . ' > /dev/null &';

        exec($cmd);

        return;
    }

    /**
     * @static
     * @param string $url Url of job
     * @param null|int $port [OPTIONAL]
     * @return bool|int Returns true on success or error code on fail
     */
    public static function start($url, $port = null)
    {
        if (null === $port) {
            $port = Qs_Job::getPort();
        }
        $ip = Qs_Job::getIp();
        $timeout = Qs_Job::getTimeout();
        $errorNumber = '';
        $errorString = '';
        $handle = fsockopen('tcp://' . $ip, $port, $errorNumber, $errorString, $timeout);
        if (!$handle) {
            $message = 'Error ' . $errorNumber . ': ' . $errorString
                . 'Connection failed: ' . 'tcp://' . $ip . ':' . $port;
            trigger_error($message, E_USER_WARNING);
            return Qs_Job::ERROR_CONNECTION_FAILED;
        }
        // TODO: check if written length less than string length
        if (false === fwrite($handle, 'START ' . $url)) {
            $message = 'Error ' . $errorNumber . ': ' . $errorString
                . 'Can not write to socket: ' . 'tcp://' . $ip . ':' . $port;
            trigger_error($message, E_USER_WARNING);
            return Qs_Job::ERROR_WRITE_SOCKET;
        }
        // TODO: check if server sent 'ACCEPTED' status
        fclose($handle);
        return true;
    }

    /**
     * @static
     * @return int
     */
    public static function getIp()
    {
        if (null === Qs_Job::$_ip) {
            Qs_Job::$_ip = Qs_Job::_getConfig('ip');
        }
        return Qs_Job::$_ip;
    }

    /**
     * Sets ip address of the script that handles the jobs
     * @static
     * @param string $ip
     * @return void
     */
    public static function setIp($ip)
    {
        Qs_Job::$_ip = $ip;
    }

    public static function getPort()
    {
        if (null === Qs_Job::$_port) {
            Qs_Job::$_port = Qs_Job::_getConfig('port');
        }
        return Qs_Job::$_port;
    }

    /**
     * Sets port of the script that handles the jobs
     * @static
     * @param int $port
     * @return void
     */
    public static function setPort($port)
    {
        Qs_Job::$_port = $port;
    }

    public static function getTimeout()
    {
        if (null === Qs_Job::$_timeout) {
            Qs_Job::$_timeout = Qs_Job::_getConfig('timeout');
        }
        return Qs_Job::$_timeout;
    }

    /**
     * Sets connection timeout in seconds
     * @param int $timeout Connection timeout in seconds
     * @return void
     */
    public function setTimeout($timeout)
    {
        Qs_Job::$_timeout = $timeout;
    }

    public static function getErrorMessage($errorNumber)
    {
        switch ($errorNumber) {
            case Qs_Job::ERROR_CONNECTION_FAILED:
                $errorMessage = 'Can not connect to the job processing script';
                break;
            case Qs_Job::ERROR_WRITE_SOCKET:
                $errorMessage = 'Can not write to the socket';
                break;
            default:
                $errorMessage = 'Unknown error';
        }
        return $errorMessage;
    }

    protected static function _getConfig($field, $default = null)
    {
        if (null === Qs_Job::$_config) {
            // Qs_Job::$_config = Qs_Config::get('job', 'qs')->toArray();
        }
        if (false === $field) {
            return Qs_Job::$_config;
        }
        if (array_key_exists($field, (array)Qs_Job::$_config)) {
            return Qs_Job::$_config[$field];
        }
        return $default;
    }
}