<?php
  
  namespace OC\Files;
  
  /**
   * class Mapper is responsible to translate logical paths to physical paths and reverse
   */
  class Mapper
  {
  	private $unchangedPhysicalRoot;
  
  	public function __construct($rootDir) {
  		$this->unchangedPhysicalRoot = $rootDir;
  	}
  
  	/**
  	 * @param string $logicPath
  	 * @param bool $create indicates if the generated physical name shall be stored in the database or not
  	 * @return string the physical path
  	 */
  	public function logicToPhysical($logicPath, $create) {
  		$physicalPath = $this->resolveLogicPath($logicPath);
  		if ($physicalPath !== null) {
  			return $physicalPath;
  		}
  
  		return $this->create($logicPath, $create);
  	}
  
  	/**
  	 * @param string $physicalPath
  	 * @return string
  	 */
  	public function physicalToLogic($physicalPath) {
  		$logicPath = $this->resolvePhysicalPath($physicalPath);
  		if ($logicPath !== null) {
  			return $logicPath;
  		}
  
  		$this->insert($physicalPath, $physicalPath);
  		return $physicalPath;
  	}
  
  	/**
  	 * @param string $path
  	 * @param bool $isLogicPath indicates if $path is logical or physical
  	 * @param $recursive
  	 * @return void
  	 */
  	public function removePath($path, $isLogicPath, $recursive) {
  		if ($recursive) {
  			$path=$path.'%';
  		}
  
  		if ($isLogicPath) {

  			\OC_DB::executeAudited('DELETE FROM `*PREFIX*file_map` WHERE `logic_path` LIKE ?', array($path));

  		} else {

  			\OC_DB::executeAudited('DELETE FROM `*PREFIX*file_map` WHERE `physic_path` LIKE ?', array($path));

  		}
  	}
  
  	/**
  	 * @param $path1
  	 * @param $path2
  	 * @throws \Exception
  	 */
  	public function copy($path1, $path2)
  	{
  		$path1 = $this->stripLast($path1);
  		$path2 = $this->stripLast($path2);
  		$physicPath1 = $this->logicToPhysical($path1, true);
  		$physicPath2 = $this->logicToPhysical($path2, true);

  		$sql = 'SELECT * FROM `*PREFIX*file_map` WHERE `logic_path` LIKE ?';
  		$result = \OC_DB::executeAudited($sql, array($path1.'%'));

  		$updateQuery = \OC_DB::prepare('UPDATE `*PREFIX*file_map`'
  			.' SET `logic_path` = ?'
  			.' , `logic_path_hash` = ?'
  			.' , `physic_path` = ?'
  			.' , `physic_path_hash` = ?'
  			.' WHERE `logic_path` = ?');
  		while( $row = $result->fetchRow()) {
  			$currentLogic = $row['logic_path'];
  			$currentPhysic = $row['physic_path'];
  			$newLogic = $path2.$this->stripRootFolder($currentLogic, $path1);
  			$newPhysic = $physicPath2.$this->stripRootFolder($currentPhysic, $physicPath1);
  			if ($path1 !== $currentLogic) {
  				try {

  					\OC_DB::executeAudited($updateQuery, array($newLogic, md5($newLogic), $newPhysic, md5($newPhysic),
  						$currentLogic));

  				} catch (\Exception $e) {
  					error_log('Mapper::Copy failed '.$currentLogic.' -> '.$newLogic.'
  '.$e);
  					throw $e;
  				}
  			}
  		}
  	}
  
  	/**
  	 * @param $path
  	 * @param $root
  	 * @return bool|string
  	 */
  	public function stripRootFolder($path, $root) {
  		if (strpos($path, $root) !== 0) {
  			// throw exception ???
  			return false;
  		}
  		if (strlen($path) > strlen($root)) {
  			return substr($path, strlen($root));
  		}
  
  		return '';
  	}
  
  	private function stripLast($path) {
  		if (substr($path, -1) == '/') {
  			$path = substr_replace($path, '', -1);
  		}
  		return $path;
  	}
  
  	private function resolveLogicPath($logicPath) {
  		$logicPath = $this->stripLast($logicPath);

  		$sql = 'SELECT * FROM `*PREFIX*file_map` WHERE `logic_path_hash` = ?';
  		$result = \OC_DB::executeAudited($sql, array(md5($logicPath)));

  		$result = $result->fetchRow();
  		if ($result === false) {
  			return null;
  		}
  
  		return $result['physic_path'];
  	}
  
  	private function resolvePhysicalPath($physicalPath) {
  		$physicalPath = $this->stripLast($physicalPath);

  		$sql = \OC_DB::prepare('SELECT * FROM `*PREFIX*file_map` WHERE `physic_path_hash` = ?');
  		$result = \OC_DB::executeAudited($sql, array(md5($physicalPath)));

  		$result = $result->fetchRow();
  
  		return $result['logic_path'];
  	}
  
  	private function create($logicPath, $store) {
  		$logicPath = $this->stripLast($logicPath);
  		$index = 0;
  
  		// create the slugified path
  		$physicalPath = $this->slugifyPath($logicPath);
  
  		// detect duplicates
  		while ($this->resolvePhysicalPath($physicalPath) !== null) {
  			$physicalPath = $this->slugifyPath($logicPath, $index++);
  		}
  
  		// insert the new path mapping if requested
  		if ($store) {
  			$this->insert($logicPath, $physicalPath);
  		}
  
  		return $physicalPath;
  	}
  
  	private function insert($logicPath, $physicalPath) {

  		$sql = 'INSERT INTO `*PREFIX*file_map` (`logic_path`, `physic_path`, `logic_path_hash`, `physic_path_hash`)
  				VALUES (?, ?, ?, ?)';
  		\OC_DB::executeAudited($sql, array($logicPath, $physicalPath, md5($logicPath), md5($physicalPath)));

  	}
  
  	public function slugifyPath($path, $index=null) {
  		$path = $this->stripRootFolder($path, $this->unchangedPhysicalRoot);
  
  		$pathElements = explode('/', $path);
  		$sluggedElements = array();
  		
  		$last= end($pathElements);
  		
  		foreach ($pathElements as $pathElement) {
  			// remove empty elements
  			if (empty($pathElement)) {
  				continue;
  			}
  
  			$sluggedElements[] = self::slugify($pathElement);
  		}
  
  		// apply index to file name
  		if ($index !== null) {
  			$last= array_pop($sluggedElements);
  			
  			// if filename contains periods - add index number before last period
  			if (preg_match('~\.[^\.]+$~i',$last,$extension)){
  				array_push($sluggedElements, substr($last,0,-(strlen($extension[0]))).'-'.$index.$extension[0]);
  			} else {
  				// if filename doesn't contain periods add index ofter the last char
  				array_push($sluggedElements, $last.'-'.$index);
  				}
  
  		}
  
  		$sluggedPath = $this->unchangedPhysicalRoot.implode('/', $sluggedElements);
  		return $this->stripLast($sluggedPath);
  	}
  
  	/**
  	 * Modifies a string to remove all non ASCII characters and spaces.
  	 *
  	 * @param string $text
  	 * @return string
  	 */
  	private function slugify($text)
  	{
  		// replace non letter or digits or dots by -
  		$text = preg_replace('~[^\\pL\d\.]+~u', '-', $text);
  
  		// trim
  		$text = trim($text, '-');
  
  		// transliterate
  		if (function_exists('iconv')) {
  			$text = iconv('utf-8', 'us-ascii//TRANSLIT//IGNORE', $text);
  		}
  
  		// lowercase
  		$text = strtolower($text);
  
  		// remove unwanted characters
  		$text = preg_replace('~[^-\w\.]+~', '', $text);
  		
  		// trim ending dots (for security reasons and win compatibility)
  		$text = preg_replace('~\.+$~', '', $text);
  
  		if (empty($text)) {
  			return uniqid();
  		}
  
  		return $text;
  	}
  }