<?php
// $Id: filebrowser.module,v 1.2 2006/08/16 11:33:41 coders Exp $

/**
 * @file
 * Enables users with appropriate permissions to browse a 
 * folder of files on an FTP-like interface.
 */

/**
 * Implementation of hook_help().
 * Provides page level help generated from description files.
 */
function filebrowser_help($section = NULL, $sethelp = NULL) {
  static $pagehelp = '';
  if (!isset($section)) {
    $pagehelp = $sethelp;
  }
  else {
    switch ($section) {
      case 'admin/modules#description':
        return t('Provides FTP-like browsing capabilities.');
      // Display help set from directory description file
      case $_GET['q']:
        if ($pagehelp) {
          return $pagehelp;
        }
    }
  }
}

/**
 * Implementation of hook_settings().
 */
function filebrowser_settings() {
  return array(
    'filebrowser_root' => array(
      '#type' => 'textfield',
      '#title' => t('Root directory'),
      '#default_value' => filebrowser_root(),
      '#maxlength' => '100',
      '#size' => '70',
      '#description' => t('Root directory used to present the filebrowser interface. Users will not be able to go up from this folder. Only a directory name under the Drupal root is accepted. Example: "public/files". No trailing slash. For super-user access to all web files, enter "." (at your own risk) '),
    ),
    'filebrowser_icons' => array(
      '#type' => 'textfield',
      '#title' => t('Icon directory'),
      '#default_value' => variable_get('filebrowser_icons', ''),
      '#maxlength' => '100',
      '#size' => '70',
      '#description' => t('Name of directory, where file type icons are stored. Files should be named "file-txt.png", "file-gif.png", etc. The default icon is "file-default.png".')
    ),
    'filebrowser_hide_description_files' => array(
      '#type' => 'radios',
      '#title' => t('Display of description files'),
      '#default_value' => variable_get('filebrowser_hide_description_files', 0),
      '#options' => array(t('Show'), t('Hide')),
      '#description' => t('Whether to show or hide description files from directory listings.'),
    )
  );
}

/**
 * Implementation of hook_perm().
 */
function filebrowser_perm() {
  return array('access filebrowser');
}

/**
 * Implementation of hook_menu().
 */
function filebrowser_menu($may_cache) {
  $items = array();
  if ($may_cache) {
    $items[] = array('path' => 'filebrowser', 'title' => t('filebrowser'),
      'access' => user_access('access filebrowser'), 'callback' => 'filebrowser_page',
      'type' => MENU_SUGGESTED_ITEM);
  }
  return $items;
}

/**
 * Prints a folder layout
 */
function filebrowser_page() {
  // Build breadcrumb list for uplevel folders
  $parts = func_get_args();
  $subfolder = join('/',$parts);
  
  // set context for later filebrowser links
  $filebrowser_base = filebrowser_base($subfolder);
  filebrowser_proper_path('', $filebrowser_base);

  filebrowser_set_breadcrumbs($parts);

  // Set page title
  drupal_set_title(t('%dirname directory', array("%dirname" => $dirname)));

  // Default list of columns to render
  $cols = array('icon','name','size','age','info');
  
  if($_REQUEST['edit']['cols']){$cols = $_REQUEST['edit']['cols'];}
  filebrowser_set_context($filebrowser_base, $cols);

  // LIST FETCHED HERE
  // No files to list, return with an empty page
  if (!($files = filebrowser_get_list($subfolder, $cols))) {
    drupal_set_message(t("Unable to get files for this directory '%subfolder'",array('%subfolder'=>$subfolder)));
    return theme("filebrowser_page", '');
  }

  // Prepare headers for display
  $headers = array_map(
    create_function(
      '$colname',
      '$func = "filebrowser_get_cell_".$colname; if(function_exists($func))return $func(""); '
    ),
    $cols
  ); 
  
  // Set sorting criteria eg. array(the 'field' key's associated value, asc/desc)
  filebrowser_sort_table(array(tablesort_get_order($headers), tablesort_get_sort($headers)));

  // Protect folders from being resorted
  $folders = array();
  foreach ($files as $rnum => $filei) {
    if ($filei['size']['data'] == '') {
      $folders[] = $filei;
      unset($files[$rnum]);
    }
  }
  usort($files, 'filebrowser_sort_table');
  $files = array_merge($folders, $files);
    
  // Drop attributes only used for sorting, so
  // these will not end up in the HTML output
  foreach($files as $rnum => $filei) {
    foreach($filei as $cnum => $cell) {
      if (is_array($cell)) {
        unset($filei[$cnum]['sv']);
      }
    }
    $files[$rnum] = $filei;
  }
    
  // Allow modules to inject content above the table
  $pre = join('', module_invoke_all('filebrowser_pre', $subfolder));

  // Allow for themeing of the table
  return theme('filebrowser_page', $files, $headers, $pre);
}

/**
 * Theme a filebrowser page, if files are available or not.
 * Here you have some possibility to reformat the data or the table layout.
 */
function theme_filebrowser_page(&$files, $header = NULL, $pre = NULL) {
  if ($files) {
    // CSS can hook on this ID to style table elements differently
    return '<div id="filebrowser-page" class="filebrowser">' . $pre . theme("table", $header, $files) . '</div>';
  }
  else {
    return '';
  }
}

/**
 * Returns a list of files in a subfolder under the admin
 * specified filebrowser root. File system details (size, last 
 * modification) is added, plus a metafile is parsed to gather
 * more information, if available.
 * @param $subfolder the folder to scan. Must be under and relative to the
 * system files dir unless $unsafe is set
 * @param $columns a list of column identifiers to show
 * @param $unsafe If set, the listing will NOT prepend the file path to the
 * subfolder. File listings from anywhere in the server become possible!
 * @return an array of table cells
 */
function filebrowser_get_list($subfolder = '', $cols = array('expander','icon','name','size','age','info'), $unsafe=FALSE) {
  $folder = ($unsafe)?$subfolder:filebrowser_safe_folder($subfolder);
  if(is_file($folder)){$folder = dirname($folder);}
  $inroot = ($folder == filebrowser_root() );

  if(!$folder){$folder='.';}  
  // Signal error in case of bogus directory name
  if (!(is_dir($folder) && ($dir = opendir($folder)))) {
    drupal_set_message($folder." was not readable");
    return FALSE;
  }

  // Collect folders and files separately and check for a metainfo file
  $files = $folders = array();
  $infofile = FALSE;
  while (($entry = readdir($dir)) !== FALSE) {
    if (is_dir("$folder/$entry")) {
      // Skip version control system folders
      if (!in_array($entry, array(".svn", "CVS"))) {
        $folders[] = $entry;
      }
    }
    else {
      // Grab information file, decide whether it should be shown or not
      if (in_array(strtolower($entry), array("descript.ion", "files.bbs"))) {
        $infofile = $entry;
        filebrowser_get_cell_info("$folder/$infofile"); // prefetch the info
        if (!variable_get('filebrowser_hide_description_files', 0)) {
          $files[] = $entry;
        }
      }
      // Display every other file
      else {
        $files[] = $entry;
      }
    }
  }
  closedir($dir);
  
  // Order folders first, then files
  sort($folders);
  sort($files);
  $files = array_merge($folders, $files);
    
    
  // Build detailed list of files
  $details = array();
  foreach ($files as $file) {
    if ( $file == '.'){continue;}
    if ($inroot && $file == '..'){continue;}
    // no up from the top, but it's allowed the rest of the time.
    
    // Some real folder or file
    $completepath = ($folder && $folder != '.') ? "$folder/$file" : $file;
    if ($stat = stat($completepath)) {
      $row = array();
      // populate the columns
      foreach($cols as $colname){
        $func = 'filebrowser_get_cell_'.$colname;
        if(function_exists($func)){
          $row[$colname] =  $func($completepath);
        }
      }
     $details[] = $row;
    }
  }
  return $details;
}


function filebrowser_build_table($files,$folder,$cols){
  $inroot = ($folder == filebrowser_root());
  // Build detailed list of files
  $details = array();
  foreach ($files as $file) {
    if ( $file == '.'){continue;}
    if ($inroot && $file == '..'){continue;}
    // the up link is now treated almost normally

    // Some real folder or file
    $completepath = "$folder/$file";
    if ($stat = stat($completepath)) {
      $row = array();
      // populate the columns
      foreach($cols as $colname){
        $func = 'filebrowser_get_cell_'.$colname;
        $row[$colname] = (function_exists($func)) ? $func($completepath) : '';
      }
     $details[] = $row;
    }
  }
  return $details;  
}


/**
 * Callback to render just one cell of data - the name link
 * A filebrowser_get_cell_hook()
 */
function filebrowser_get_cell_name($completepath){
  if(! $completepath){return array('data' => t("Name"), 'field' => 'name');  }
  $file = basename($completepath);
  if (is_dir($completepath)) {
    // for this link I need to prefix the filebrowser relink, BUT chop the filebrowser directory part
    $relpath = filebrowser_trim_root($completepath);
    $href = filebrowser_proper_path($relpath);
  }
  else {
    $href = $completepath;
  }
  if ($file == ".." ) { $file = ".. up " ;}

  $link = l($file, $href);
  return array('data' => $link, 'class' => 'filename', 'sv' => $file);
}


/**
 * Return the formatted size of this file.
 * A filebrowser_get_cell_hook()
 */
function filebrowser_get_cell_size($completepath){
  if(! $completepath){return array('data' => t("Size"), 'field' => 'size');  }
  if(is_dir($completepath)){return array();}
  $size = filesize($completepath);
  return array('data' => $size?format_size($size):'', 'class' => 'size', 'sv' => ($size ? $size : 0));
} 

/**
 * Return the formatted age of this file.
 * A filebrowser_get_cell_hook()
 */
function filebrowser_get_cell_age($completepath){
  if(! $completepath){return array('data' => t("Age"), 'field' => 'age');  }
  $age = time() - filemtime($completepath);
  return array('data' => format_interval($age), 'class' => 'age', 'sv' => $age);
} 

/**
 * Return the deduced description or extended info for this file.
 * A filebrowser_get_cell_hook()
 */
function filebrowser_get_cell_info($completepath){
  if(! $completepath){return array('data' => t("Info"));  }
  static $info;

  if(! isset($info)){
    // The first time this cell is requested, look hard into the current directory
    // cache results
    if(!is_file($completepath)){
      $subfolder = (is_dir($completepath))?$completepath:dirname($completepath);
      $completepath = $subfolder.'/descript.ion'; 
      if(! file_exists($completepath)){
        $completepath = $subfolder.'/files.bbs';
      }
    }

    if(is_file($completepath)){
      $info = filebrowser_get_fileinfo($completepath, dirname($completepath));
    }
    else {
      $info = array();
    }
  } 

  $file = basename($completepath);
  // each info returned was an array. - not sure how to deal with that in one cell
  $detail = (is_array($info[$file])) ? array_pop($info[$file]) : $info[$file] ;
  return array('data' => $detail, 'class' => 'info');
} 



/**
 * Loads file metainformation from the specified file. Also
 * allows the file to specify a *callback* with which the
 * descriptions are parsed, so more metainformation can be
 * presented on the output.
 */
function filebrowser_get_fileinfo($fullpath = NULL, $subfolder = '') {
  static $metacols = array();

  // Return (previously generated) meta column list
  if (!isset($fullpath)) {
    return $metacols;
  }
  
  // Build meta information list
  $metainfo = array();
  if (is_readable($fullpath) && ($file = file($fullpath))) {
    foreach ($file as $line) {
      // Skip empty and commented lines 
      if (trim($line) == '' || strpos(trim($line), '#') === 0) {
        continue;
      }
      list($name, $description) = explode(" ", $line, 2);
      if (isset($metainfo[$name])) {
        $metainfo[$name] .= trim($description) . " ";
      }
      else {
        $metainfo[$name] = trim($description) . " ";
      }
    }
    
    $callback = FALSE;
    if (isset($metainfo['*callback*']) && function_exists(trim($metainfo['*callback*']))) {
      $callback = trim($metainfo['*callback*']);
      unset($metainfo['*callback*']);
    }
    if (isset($metainfo['.'])) {
      filebrowser_help(NULL, $metainfo['.']);
      unset($metainfo['.']);
    }
    
    foreach ($metainfo as $name => $description) {
      $metainfo[$name] = ($callback ? $callback(trim($description), $subfolder, $name) : array(trim($description)));
    }
    $metacols = ($callback ? $callback() : array(t('Description')));
  }
  return $metainfo;
}

/**
 * Returns the appropriate HTML code for an icon representing
 * a file, based on the extension of the file. A specific icon
 * can also be requested with the second parameter.
 */
function filebrowser_get_cell_icon($fullpath = NULL, $iconname = NULL) {
  if (isset($fullpath)) {
    $iconname = (is_dir($fullpath) ? 'folder' : preg_replace("!^.+\\.([^\\.]+)$!", "\\1", $fullpath));
  }
  elseif (!isset($iconname)) {
    $iconname = 'default';
  }
  $iconfiles = array(
    variable_get('filebrowser_icons', '') . "/file-$iconname.png",
    variable_get('filebrowser_icons', '') . "/file-default.png"
  );
  foreach ($iconfiles as $icon) {
    if (file_exists($icon)) {
      return theme("image", $icon, $iconname." file", $iconname." file");
    }
  }
  return '';
}

/**
 * Convert windows path values to use slashes, prevent slashes used 
 * repeatedly, and try to catch and eliminate path walkback attemepts.
 * Also prevent from accessing version control system folders.
 */
function filebrowser_safe_folder($subfolder) {
  $folder = filebrowser_root() . ($subfolder?"/$subfolder":'');
  while (TRUE) {
    $safer = str_replace(array("\\", "../", "/.svn", "/CVS", ".."), array("/", "", "", "", ""), $folder);
    if ($safer !== $folder) {
      $folder = $safer;
    }
    else {
      break;
    }
  }
  $folder = preg_replace("!^/*([^/].+[^/])/*$!", "\\1", $folder);
  // handle the case when superuser has set files folder to '.'
  $folder = preg_replace("!^./!", "", $folder); 
  return preg_replace("!/+!", "/", $folder);
}

/**
 * Prepend the filebrowser location to the path.
 * Allows  easy path generation even if $path has a leading slash. Setting the
 * second parameter allows filebrowser to run from different contexts.
 * @param $path
 * @param $filebrowser_base 
 * 				Define where filebrowser is run from. Requires trailing slash.
 */
function filebrowser_proper_path($path, $filebrowser_base=NULL) {
  static $base; if(!$base){$base='filebrowser/';}
  if($filebrowser_base){$base=$filebrowser_base;}
  return preg_replace("|//+|", "/", $base.'/'.$path);
}

/**
 * Does the custom sorting of the table contents based on the
 * sort values (sv) added previously.
 * Note this sorts by named columns, not field numbers as tablesort usually
 * does.
 */
function filebrowser_sort_table($a, $b = NULL) {
  static $orderby = 0;
  static $sort = '';
  // Set sorting criteria
  if (!isset($b)) {
    $orderby = $a[0]['sql']; // NAME of field to sort with
    $sort = $a[1]; // asc/desc
  }
  // Sort two values with the sorting criteria
  elseif (is_array($a) && isset($a[$orderby]) && isset($a[$orderby]['sv'])) {
    if ($a[$orderby]['sv'] == $b[$orderby]['sv']) {
      return 0;
    }
    if ($sort == 'asc') {
      return $a[$orderby]['sv'] > $b[$orderby]['sv'];
    }
    else {
      return $a[$orderby]['sv'] < $b[$orderby]['sv'];
    }
  }
}

function filebrowser_set_breadcrumbs($parts){
  $breadcrumb = array();
  $dirname = t('root');
  if ($parts) {
    $breadcrumb[] = $dirname = array_pop($parts);
    while (count($parts)) {
      $breadcrumb[] = l($parts[count($parts) -1], filebrowser_proper_path(join("/", $parts)));
      array_pop($parts);
    }
    $breadcrumb[] = l(t('Filebrowser root'), filebrowser_proper_path(''));
  } else {
    $breadcrumb[] = t('Filebrowser');
  }
  $breadcrumb[] = l(t('Home'), NULL);
  drupal_set_breadcrumb(array_reverse($breadcrumb));
}

/**
 * Returns the base of the allowed area for filebrowsing.
 * May be independant of the files directory, and different for different users.
 */
function filebrowser_root(){
  return variable_get('filebrowser_root', file_directory_path());
}
/**
 * Chop the filebrowser root directory (not the url base) off the start of a
 * path - translate from a filepath to a relative path.
 *
 * May operate by reference.
 */
function filebrowser_trim_root(&$path){
  $fbr = filebrowser_root();
  if(substr($path,0,strlen($fbr)) == $fbr){
    $path = substr($path,strlen($fbr)+1); // trim slash also
  }
  return $path;
}

/**
 * Separate the request from the function.
 * Custom filebrowsers can be invoked from any path on the server, and their
 * relative subfolders are tacked onto the end of the URL.
 * 
 *    [admin/custom/filebrowser/][my/special/files]
 * 
 * Find where to split this request.
 * @return the base filebrowser path for the current job. Contains trailing
 * slash.
 */
function filebrowser_base($subfolder){
  $filebrowser_base = $subfolder ? substr($_GET['q'],0,strpos($_GET['q'],$subfolder)) : $_GET['q'].'/';
  return $filebrowser_base;
}

/**
 * Tell the system to remember what cols to display when this lookup is called
 * again by ajax. An internal memo, so the page which is called asynchronously
 * knows what its parent expects to see.
 */
function filebrowser_set_context($context, $cols){
  $filebrowser_contexts = variable_get('filebrowser_contexts',array());
  $filebrowser_contexts[$context] = $cols;
  variable_set('filebrowser_contexts',$filebrowser_contexts);
}