<?php
  /**
   * Copyright (c) 2012 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\Storage;

  require_once __DIR__ . '/../3rdparty/smb4php/smb.php';

  
  class SMB extends \OC\Files\Storage\StreamWrapper{
  	private $password;
  	private $user;
  	private $host;
  	private $root;
  	private $share;
  
  	public function __construct($params) {
  		if (isset($params['host']) && isset($params['user']) && isset($params['password']) && isset($params['share'])) {
  			$this->host=$params['host'];
  			$this->user=$params['user'];
  			$this->password=$params['password'];
  			$this->share=$params['share'];
  			$this->root=isset($params['root'])?$params['root']:'/';
  			if ( ! $this->root || $this->root[0]!='/') {
  				$this->root='/'.$this->root;
  			}
  			if (substr($this->root, -1, 1)!='/') {
  				$this->root.='/';
  			}
  			if ( ! $this->share || $this->share[0]!='/') {
  				$this->share='/'.$this->share;
  			}
  			if (substr($this->share, -1, 1)=='/') {
  				$this->share = substr($this->share, 0, -1);
  			}
  		} else {

  			throw new \Exception('Invalid configuration');

  		}
  	}
  
  	public function getId(){
  		return 'smb::' . $this->user . '@' . $this->host . '/' . $this->share . '/' . $this->root;
  	}
  
  	public function constructUrl($path) {
  		if (substr($path, -1)=='/') {

  			$path = substr($path, 0, -1);

  		}

  		if (substr($path, 0, 1)=='/') {
  			$path = substr($path, 1);
  		}
  		// remove trailing dots which some versions of samba don't seem to like
  		$path = rtrim($path, '.');

  		$path = urlencode($path);
  		$user = urlencode($this->user);
  		$pass = urlencode($this->password);
  		return 'smb://'.$user.':'.$pass.'@'.$this->host.$this->share.$this->root.$path;
  	}
  
  	public function stat($path) {
  		if ( ! $path and $this->root=='/') {//mtime doesn't work for shares

  			$stat=stat($this->constructUrl($path));

  			if (empty($stat)) {
  				return false;
  			}
  			$mtime=$this->shareMTime();

  			$stat['mtime']=$mtime;
  			return $stat;
  		} else {

  			$stat = stat($this->constructUrl($path));
  
  			// smb4php can return an empty array if the connection could not be established
  			if (empty($stat)) {
  				return false;
  			}
  
  			return $stat;
  		}
  	}
  
  	/**
  	 * Unlinks file or directory

  	 * @param string $path

  	 */
  	public function unlink($path) {
  		if ($this->is_dir($path)) {
  			$this->rmdir($path);
  		}
  		else {
  			$url = $this->constructUrl($path);
  			unlink($url);
  			clearstatcache(false, $url);

  		}

  		// smb4php still returns false even on success so
  		// check here whether file was really deleted
  		return !file_exists($path);

  	}
  
  	/**
  	 * check if a file or folder has been updated since $time
  	 * @param string $path
  	 * @param int $time
  	 * @return bool
  	 */
  	public function hasUpdated($path,$time) {
  		if(!$path and $this->root=='/') {
  			// mtime doesn't work for shares, but giving the nature of the backend,
  			// doing a full update is still just fast enough
  			return true;
  		} else {
  			$actualTime=$this->filemtime($path);
  			return $actualTime>$time;
  		}
  	}
  
  	/**
  	 * get the best guess for the modification time of the share
  	 */
  	private function shareMTime() {
  		$dh=$this->opendir('');
  		$lastCtime=0;
  		if(is_resource($dh)) {
  			while (($file = readdir($dh)) !== false) {
  				if ($file!='.' and $file!='..') {
  					$ctime=$this->filemtime($file);
  					if ($ctime>$lastCtime) {
  						$lastCtime=$ctime;
  					}
  				}
  			}
  		}
  		return $lastCtime;
  	}

  
  	/**
  	 * check if smbclient is installed
  	 */
  	public static function checkDependencies() {
  		if (function_exists('shell_exec')) {
  			$output=shell_exec('command -v smbclient 2> /dev/null');
  			if (!empty($output)) {
  				return true;
  			}
  		}
  		return array('smbclient');
  	}

  }