<?php
  /**
   * Copyright (c) 2013 Robin Appelman <icewind@owncloud.com>
   * This file is licensed under the Affero General Public License version 3 or
   * later.
   * See the COPYING-README file.
   */
  
  namespace OC\Files\Stream;
  
  class StaticStream {

  	const MODE_FILE = 0100000;

  	public $context;
  	protected static $data = array();
  
  	protected $path = '';
  	protected $pointer = 0;
  	protected $writable = false;
  
  	public function stream_close() {
  	}
  
  	public function stream_eof() {
  		return $this->pointer >= strlen(self::$data[$this->path]);
  	}
  
  	public function stream_flush() {
  	}

  	public static function clear() {
  		self::$data = array();
  	}

  	public function stream_open($path, $mode, $options, &$opened_path) {
  		switch ($mode[0]) {
  			case 'r':
  				if (!isset(self::$data[$path])) return false;
  				$this->path = $path;
  				$this->writable = isset($mode[1]) && $mode[1] == '+';
  				break;
  			case 'w':
  				self::$data[$path] = '';
  				$this->path = $path;
  				$this->writable = true;
  				break;
  			case 'a':
  				if (!isset(self::$data[$path])) self::$data[$path] = '';
  				$this->path = $path;
  				$this->writable = true;
  				$this->pointer = strlen(self::$data[$path]);
  				break;
  			case 'x':
  				if (isset(self::$data[$path])) return false;
  				$this->path = $path;
  				$this->writable = true;
  				break;
  			case 'c':
  				if (!isset(self::$data[$path])) self::$data[$path] = '';
  				$this->path = $path;
  				$this->writable = true;
  				break;
  			default:
  				return false;
  		}
  		$opened_path = $this->path;
  		return true;
  	}
  
  	public function stream_read($count) {
  		$bytes = min(strlen(self::$data[$this->path]) - $this->pointer, $count);
  		$data = substr(self::$data[$this->path], $this->pointer, $bytes);
  		$this->pointer += $bytes;
  		return $data;
  	}
  
  	public function stream_seek($offset, $whence = SEEK_SET) {
  		$len = strlen(self::$data[$this->path]);
  		switch ($whence) {
  			case SEEK_SET:
  				if ($offset <= $len) {
  					$this->pointer = $offset;
  					return true;
  				}
  				break;
  			case SEEK_CUR:
  				if ($this->pointer + $offset <= $len) {
  					$this->pointer += $offset;
  					return true;
  				}
  				break;
  			case SEEK_END:
  				if ($len + $offset <= $len) {
  					$this->pointer = $len + $offset;
  					return true;
  				}
  				break;
  		}
  		return false;
  	}
  
  	public function stream_stat() {

  		return $this->url_stat($this->path);

  	}
  
  	public function stream_tell() {
  		return $this->pointer;
  	}
  
  	public function stream_write($data) {
  		if (!$this->writable) return 0;
  		$size = strlen($data);
  		if ($this->stream_eof()) {
  			self::$data[$this->path] .= $data;
  		} else {
  			self::$data[$this->path] = substr_replace(
  				self::$data[$this->path],
  				$data,
  				$this->pointer
  			);
  		}
  		$this->pointer += $size;
  		return $size;
  	}
  
  	public function unlink($path) {
  		if (isset(self::$data[$path])) {
  			unset(self::$data[$path]);
  		}
  		return true;
  	}
  
  	public function url_stat($path) {
  		if (isset(self::$data[$path])) {
  			$size = strlen(self::$data[$path]);
  			$time = time();

  			$data = array(

  				'dev' => 0,

  				'ino' => 0,

  				'mode' => self::MODE_FILE | 0777,

  				'nlink' => 1,

  				'uid' => 0,

  				'gid' => 0,

  				'rdev' => '',

  				'size' => $size,

  				'atime' => $time,

  				'mtime' => $time,

  				'ctime' => $time,

  				'blksize' => -1,

  				'blocks' => -1,
  			);

  			return array_values($data) + $data;

  		}
  		return false;
  	}
  }