<?php

/**

 * PHP-Gettext External Library: StreamReader classes

 *

 * @package External

 * @subpackage PHP-gettext

 *

 * @internal

   Copyright (c) 2003, 2005 Danilo Segan <danilo@kvota.net>.

   This file is part of PHP-gettext.

   PHP-gettext is free software; you can redistribute it and/or modify

   it under the terms of the GNU General Public License as published by

   the Free Software Foundation; either version 2 of the License, or

   (at your option) any later version.

   PHP-gettext is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License

   along with PHP-gettext; if not, write to the Free Software

   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 */

// Simple class to wrap file streams, string streams, etc.

// seek is essential, and it should be byte stream

class StreamReader {

  // should return a string [FIXME: perhaps return array of bytes?]

  function read($bytes) {

    return false;

  }

  // should return new position

  function seekto($position) {

    return false;

  }

  // returns current position

  function currentpos() {

    return false;

  }

  // returns length of entire stream (limit for seekto()s)

  function length() {

    return false;

  }

}

class StringReader {

  var $_pos;

  var $_str;

  function StringReader($str='') {

    $this->_str = $str;

    $this->_pos = 0;

    // If string functions are overloaded, we need to use the mb versions

    $this->is_overloaded = ((ini_get("mbstring.func_overload") & 2) != 0) && function_exists('mb_substr');

  }

  function _substr($string, $start, $length) {

	if ($this->is_overloaded) {

		return mb_substr($string,$start,$length,'ascii');

	} else {

		return substr($string,$start,$length);

	}

  }

  function _strlen($string) {

	if ($this->is_overloaded) {

		return mb_strlen($string,'ascii');

	} else {

		return strlen($string);

	}

  }

  function read($bytes) {

	  $data = $this->_substr($this->_str, $this->_pos, $bytes);

    $this->_pos += $bytes;

    if ($this->_strlen($this->_str)<$this->_pos)

      $this->_pos = $this->_strlen($this->_str);

    return $data;

  }

  function seekto($pos) {

    $this->_pos = $pos;

    if ($this->_strlen($this->_str)<$this->_pos)

      $this->_pos = $this->_strlen($this->_str);

    return $this->_pos;

  }

  function currentpos() {

    return $this->_pos;

  }

  function length() {

    return $this->_strlen($this->_str);

  }

}

class FileReader {

  var $_pos;

  var $_fd;

  var $_length;

  function FileReader($filename) {

    if (file_exists($filename)) {

      $this->_length=filesize($filename);

      $this->_pos = 0;

      $this->_fd = fopen($filename,'rb');

      if (!$this->_fd) {

	$this->error = 3; // Cannot read file, probably permissions

	return false;

      }

    } else {

      $this->error = 2; // File doesn't exist

      return false;

    }

  }

  function read($bytes) {

    if ($bytes) {

      fseek($this->_fd, $this->_pos);

      // PHP 5.1.1 does not read more than 8192 bytes in one fread()

      // the discussions at PHP Bugs suggest it's the intended behaviour

      while ($bytes > 0) {

        $chunk  = fread($this->_fd, $bytes);

        $data  .= $chunk;

        $bytes -= strlen($chunk);

      }

      $this->_pos = ftell($this->_fd);

      return $data;

    } else return '';

  }

  function seekto($pos) {

    fseek($this->_fd, $pos);

    $this->_pos = ftell($this->_fd);

    return $this->_pos;

  }

  function currentpos() {

    return $this->_pos;

  }

  function length() {

    return $this->_length;

  }

  function close() {

    fclose($this->_fd);

  }

}

// Preloads entire file in memory first, then creates a StringReader

// over it (it assumes knowledge of StringReader internals)

class CachedFileReader extends StringReader {

  function CachedFileReader($filename) {

    parent::StringReader();

    if (file_exists($filename)) {

      $length=filesize($filename);

      $fd = fopen($filename,'rb');

      if (!$fd) {

        $this->error = 3; // Cannot read file, probably permissions

        return false;

      }

      $this->_str = fread($fd, $length);

	  fclose($fd);

    } else {

      $this->error = 2; // File doesn't exist

      return false;

    }

  }

}

?>