<?php
/**
 * Ftp Destination Connect to Service.
 *
 * @since   3.5.0
 */

/**
 * Class BackWPup_Destination_Ftp_Connect.
 *
 * @since   3.5.0
 */
class BackWPup_Destination_Ftp_Connect implements BackWPup_Destination_Connect_Interface
{
    /**
     * Host.
     *
     * @since 3.5.0
     *
     * @var string The host to connect
     */
    private $host;

    /**
     * User.
     *
     * @since 3.5.0
     *
     * @var string The user name
     */
    private $user;

    /**
     * Pass.
     *
     * @since 3.5.0
     *
     * @var string The user password
     */
    private $pass;

    /**
     * Port.
     *
     * @since 3.5.0
     *
     * @var int The port where the resource is listen for
     */
    private $port;

    /**
     * Connection timeout.
     *
     * @since 3.5.0
     * @see   ftp_connect()
     *
     * @var int The connectin timeout
     */
    private $timeout;

    /**
     * Use ssl.
     *
     * @since 3.5.0
     *
     * @var bool To use ssl or not
     */
    private $use_ssl;

    /**
     * Passive.
     *
     * @since 3.5.0
     *
     * @var bool True to set passive mode, false otherwise
     */
    private $passive;

    /**
     * The Resource or Stream to the service.
     *
     * @since 3.5.0
     *
     * @var mixed Depending on the type of the connection
     */
    private $resource;

    /**
     * BackWPup_Destination_Ftp_Connect constructor.
     *
     * @since 3.5.0
     *
     * @param string $host    the host to connect
     * @param string $user    the user name for host
     * @param string $pass    the password for host
     * @param int    $port    the port in which the service is listen for
     * @param int    $timeout the connection timeout
     * @param bool   $use_ssl to connect over ssl
     * @param bool   $passive connetion should be passive or not
     */
    public function __construct($host, $user, $pass, $port, $timeout, $use_ssl, $passive)
    {
        if (!is_string($host) || '' === $host) {
            throw new \InvalidArgumentException('Invalid HOST value. The host must be a valid string.');
        }
        if (!is_string($user) || '' === $user) {
            throw new \InvalidArgumentException('Invalid USER value. The user must be a valid username string.');
        }
        if (!is_string($pass) || '' === $pass) {
            throw new \InvalidArgumentException('Invalid PASSWORD value. The user must be a valid password string.');
        }

        $this->host = $host;
        $this->user = $user;
        $this->pass = $pass;
        $this->port = $port ?: 21;
        $this->timeout = $timeout ?: 90;
        $this->use_ssl = function_exists('ftp_ssl_connect') && $use_ssl;
        $this->passive = (bool) $passive;
        $this->resource = null;
    }

    /**
     * {@inheritdoc}
     */
    public function connect()
    {
        // Don't execute the connection twice.
        if ($this->resource) {
            return $this;
        }

        if (!function_exists('ftp_connect')) {
            throw new \BackWPup_Destination_Connect_Exception(
                'Function ftp_connect does not exists. No way to connect to the server.'
            );
        }

        // Default connection type.
        $resource = ftp_connect($this->host, $this->port, $this->timeout);

        // Can be connected over ssl?
        if ($this->use_ssl) {
            $resource = ftp_ssl_connect($this->host, $this->port, $this->timeout);
        }

        if (!$resource) {
            throw new \BackWPup_Destination_Connect_Exception(
                'Something went wrong during FTP connection. Seems not possible to connect to the service.'
            );
        }

        $this->resource = $resource;

        if (!$this->login()) {
            throw new BackWPup_Destination_Connect_Exception(
                'Something went wrong during FTP connection. Seems not possible to connect to the service.'
            );
        }

        ftp_pasv($this->resource, $this->passive);

        return $this;
    }

    /**
     * {@inheritdoc}
     */
    public function resource()
    {
        return $this->resource;
    }

    /**
     * Get the FTP URL.
     *
     * @param string $path The path to the FTP file
     *
     * @return string the URL to the FTP server
     */
    public function getURL($path = null)
    {
        if ($path !== null && substr($path, 0, 1) != '/') {
            $path = '/' . $path;
        }

        return ($this->use_ssl ? 'ftps://' : 'ftp://') .
        rawurlencode($this->user) . ':' . rawurlencode($this->pass) .
        '@' . rawurlencode($this->host) . ':' . intval($this->port) . $path;
    }

    /**
     * Login.
     *
     * Perform a login to the service.
     *
     * @throws BackWPup_Destination_Connect_Exception in case isn't possible to login
     *
     * @since 3.5.0
     *
     * @return bool true if was able to login, false otherwise
     */
    private function login()
    {
        $response = false;

        if (@ftp_login($this->resource, $this->user, $this->pass)) {
            $response = true;
        }

        if (!$response) {
            ftp_raw($this->resource, 'USER ' . $this->user);
            $response = ftp_raw($this->resource, 'PASS ' . $this->pass);
        }

        // Since the ftp_raw returns an array, we check for false value.
        if (is_array($response) && substr(trim($response[0]), 0, 3) > 400) {
            $response = false;
        }

        return $response;
    }
}