Method copy

/**
 * Copy a folder.
 *
 * @param   string   $src         The path to the source folder.
 * @param   string   $dest        The path to the destination folder.
 * @param   string   $path        An optional base path to prefix to the file names.
 * @param   boolean  $force       Force copy.
 * @param   boolean  $useStreams  Optionally force folder/file overwrites.
 *
 * @return  boolean  True on success.
 *
 * @since   1.7.0
 * @throws  \RuntimeException
 */
public static function copy($src, $dest, $path = '', $force = false, $useStreams = false)
{
    @set_time_limit(ini_get('max_execution_time'));
    $FTPOptions = ClientHelper::getCredentials('ftp');
    if ($path) {
        $src = Path::clean($path . '/' . $src);
        $dest = Path::clean($path . '/' . $dest);
    }
    // Eliminate trailing directory separators, if any
    $src = rtrim($src, DIRECTORY_SEPARATOR);
    $dest = rtrim($dest, DIRECTORY_SEPARATOR);
    if (!self::exists($src)) {
        throw new \RuntimeException('Source folder not found', -1);
    }
    if (self::exists($dest) && !$force) {
        throw new \RuntimeException('Destination folder already exists', -1);
    }
    // Make sure the destination exists
    if (!self::create($dest)) {
        throw new \RuntimeException('Cannot create destination folder', -1);
    }
    // If we're using ftp and don't have streams enabled
    if ($FTPOptions['enabled'] == 1 && !$useStreams) {
        // Connect the FTP client
        $ftp = FtpClient::getInstance($FTPOptions['host'], $FTPOptions['port'], array(), $FTPOptions['user'], $FTPOptions['pass']);
        if (!($dh = @opendir($src))) {
            throw new \RuntimeException('Cannot open source folder', -1);
        }
        // Walk through the directory copying files and recursing into folders.
        while (($file = readdir($dh)) !== false) {
            $sfid = $src . '/' . $file;
            $dfid = $dest . '/' . $file;
            switch (filetype($sfid)) {
                case 'dir':
                    if ($file != '.' && $file != '..') {
                        $ret = self::copy($sfid, $dfid, null, $force);
                        if ($ret !== true) {
                            return $ret;
                        }
                    }
                    break;
                case 'file':
                    // Translate path for the FTP account
                    $dfid = Path::clean(str_replace(JPATH_ROOT, $FTPOptions['root'], $dfid), '/');
                    if (!$ftp->store($sfid, $dfid)) {
                        throw new \RuntimeException('Copy file failed', -1);
                    }
                    break;
            }
        }
    } else {
        if (!($dh = @opendir($src))) {
            throw new \RuntimeException('Cannot open source folder', -1);
        }
        // Walk through the directory copying files and recursing into folders.
        while (($file = readdir($dh)) !== false) {
            $sfid = $src . '/' . $file;
            $dfid = $dest . '/' . $file;
            switch (filetype($sfid)) {
                case 'dir':
                    if ($file != '.' && $file != '..') {
                        $ret = self::copy($sfid, $dfid, null, $force, $useStreams);
                        if ($ret !== true) {
                            return $ret;
                        }
                    }
                    break;
                case 'file':
                    if ($useStreams) {
                        $stream = Factory::getStream();
                        if (!$stream->copy($sfid, $dfid)) {
                            throw new \RuntimeException(sprintf("Cannot copy file: %s", Path::removeRoot($stream->getError())), -1);
                        }
                    } else {
                        if (!@copy($sfid, $dfid)) {
                            throw new \RuntimeException('Copy file failed', -1);
                        }
                    }
                    break;
            }
        }
    }
    return true;
}