<?php
/**
 * @package     Joomla.Platform
 * @subpackage  FileSystem
 *
 * @copyright   Copyright (C) 2005 - 2011 Open Source Matters, Inc. All rights reserved.
 * @license     GNU General Public License version 2 or later; see LICENSE
 */

defined('JPATH_PLATFORM') or die;

jimport('joomla.filesystem.support.stringcontroller');

/**
 * String Stream Wrapper
 *
 * This class allows you to use a PHP string like
 * you would normally use a regular stream wrapper
 *
 * @package     Joomla.Platform
 * @subpackage  FileSystem
 * @since       11.1
 */
class JStreamString
{
    private $_currentstring;

    private $_path;

    private $_mode;

    private $_options;

    private $_opened_path;

    private $_pos;

    private $_len;

    private $_stat;

    /**
     * @param   $path
     * @param   $mode
     * @param   $options
     * @param   $opened_path
     *
     * @return  boolean
     * @since   11.1
     */
    function stream_open($path, $mode, $options, &$opened_path)
    {
        $this->_currentstring = &JStringController::getRef(str_replace('string://','',$path));

        if($this->_currentstring) {
            $this->_len = strlen($this->_currentstring);
            $this->_pos = 0;
            $this->_stat = $this->url_stat($path, 0);

            return true;
        }
        else {

            return false;
        }
    }

    /**
     * @return
     * @since   11.1
     */
    function stream_stat()
    {
        return $this->_stat;
    }

    /**
     * @param   $path
     * @param   $flags
     *
     * @return
     * @since   11.1
     */
    function url_stat($path, $flags = 0)
    {
        $now = time();
        $string = &JStringController::getRef(str_replace('string://','',$path));
        $stat = array(
            'dev'       => 0,
            'ino'       => 0,
            'mode'      => 0,
            'nlink'     => 1,
            'uid'       => 0,
            'gid'       => 0,
            'rdev'      => 0,
            'size'      => strlen($string),
            'atime'     => $now,
            'mtime'     => $now,
            'ctime'     => $now,
            'blksize'   => '512',
            'blocks'    => ceil(strlen($string) / 512)
        );

        return $stat;
    }

    /**
     * @param   $count
     *
     * @return
     * @since   11.1
     */
    function stream_read($count)
    {
        $result = substr($this->_currentstring, $this->_pos, $count);
        $this->_pos += $count;

        return $result;
    }

    /**
     * @return  boolean
     * @since   11.1
     */
    function stream_write($data)
    {
        // We don't support updating the string.
        return false;
    }

    /**
     * @return
     * @since   11.1
     */
    function stream_tell()
    {
        return $this->_pos;
    }

    /**
     * @return  boolean
     * @since   11.1
     */
    function stream_eof()
    {
        if ($this->_pos > $this->_len) {
            return true;
        }

        return false;
    }

    /**
     * @param   $offset
     * @param   $whence
     *
     * @return
     * @since   11.1
     */
    function stream_seek($offset, $whence)
    {
        // $whence: SEEK_SET, SEEK_CUR, SEEK_END
        if ($offset > $this->_len) {
            // We can't seek beyond our len.
            return false; 
        }

        switch($whence)
        {
            case SEEK_SET:
                $this->_pos = $offset;
                break;

            case SEEK_CUR:
                if (($this->_pos + $offset) < $this->_len) {
                    $this->_pos += $offset;
                }
                else {
                    return false;
                }
                break;

            case SEEK_END:
                $this->_pos = $this->_len - $offset;
                break;
        }

        return true;
    }

    /**
     * @return  boolean
     * @since   11.1
     */
    function stream_flush()
    {
        // We don't store data.
        return true; 
    }
}

stream_wrapper_register('string', 'JStreamString') or die(JText::_('JLIB_FILESYSTEM_STREAM_FAILED'));