<?php


/**
 * @file
 * A destination type for saving locally to the server.
 */

/**
 * A destination type for saving locally to the server.
 *
 * @ingroup backup_migrate_destinations
 */

class backup_migrate_destination_files extends backup_migrate_destination {
  var $supported_ops = array('scheduled backup', 'manual backup', 'restore', 'list files', 'configure', 'delete');

  function type_name() {
    return t("Server Directory");
  }

  /**
   * Get the file location.
   */
  function get_realpath() {
    return drupal_realpath($this->get_location());
  }

  /**
   * File save destination callback.
   */
  function _save_file($file, $settings) {
    if ($dir = $this->get_location()) {
      if ($dir = $this->check_dir($dir)) {
        $filepath = rtrim($dir, "/") ."/". $file->filename();
        if (file_unmanaged_move($file->filepath(), $filepath)) {
  
          // chmod, chown and chgrp the file if needed.
          if ($chmod = $this->settings('chmod')) {
            if (!@drupal_chmod($filepath, octdec($chmod))) {
              _backup_migrate_message('Unable to set the file mode for: @file', array('@file' => $filepath), 'error');
            }
          }
          if ($chgrp = $this->settings('chgrp')) {
            if (!@chgrp($filepath, $chgrp)) {
              _backup_migrate_message('Unable to set the file group for: @file', array('@file' => $filepath), 'error');
            }
          }
          return $file;
        }
        else {
          _backup_migrate_message('Unable to save the file to the directory: @dir', array('@dir' => $dir), 'error');
        }
      }
    }
  }

  /**
   * Determine if we can read the given file.
   */
  function can_read_file($file_id) {
    return $this->op('restore') && is_readable($this->get_filepath($file_id));
  }

  /**
   * File load destination callback.
   */
  function load_file($file_id) {
    $filepath = $this->get_filepath($file_id);
    if (file_exists($filepath)) {
      backup_migrate_include('files');
      return new backup_file(array('filepath' => $filepath));
    }
  }

  /**
   * File list destination callback.
   */
  function _list_files() {
    $files = array();
    if ($dir = $this->get_realpath()) {
      if ($handle = @opendir($dir)) {
        backup_migrate_include('files');
        while (FALSE !== ($file = readdir($handle))) {
          $filepath = $dir ."/". $file;
          $files[$file] = new backup_file(array('filepath' => $filepath));
        }
      }
    }
    return $files;
  }

  /**
   * File delete destination callback.
   */
  function _delete_file($file_id) {
    $filepath = $this->get_filepath($file_id);
    file_unmanaged_delete($filepath);
  }

  /**
   * Get the filepath from the given file id.
   */
  function get_filepath($file_id) {
    if ($dir = $this->get_realpath()) {
      $filepath = rtrim($dir, '/') .'/'. $file_id;
      return $filepath;
    }
    return FALSE;
  }

  /**
   * Get the form for the settings for the files destination.
   */
  function edit_form() {
    $form = parent::edit_form();
    $form['location'] = array(
      "#type" => "textfield",
      "#title" => t("Directory path"),
      "#default_value" => $this->get_location(),
      "#required" => TRUE,
      "#description" => t('Enter the path to the directory to save the backups to. Use a relative path to pick a path relative to your Drupal root directory. The web server must be able to write to this path.'),
    );
    $form['settings'] = array(
      '#type' => 'fieldset',
      '#title' => t('Advanced Settings'),
      '#tree' => TRUE,
      '#collapsible' => TRUE,
      '#collapsed' => TRUE,
    );
    if (function_exists('chmod')) {
      $form['settings']['chmod'] = array(
        '#type' => 'textfield',
        '#title' => t('Change file mode (chmod)'),
        '#size' => 5,
        '#default_value' => $this->settings('chmod'),
        '#description' => t('If you enter a value here, backup files will be chmoded with the mode you specify. Specify the mode in octal form (e.g. 644 or 0644) or leave blank to disable this feature.'),
      );
    }
    if (function_exists('chgrp')) {
      $form['settings']['chgrp'] = array(
        '#type' => 'textfield',
        '#title' => t('Change file group (chgrp)'),
        '#size' => 5,
        '#default_value' => $this->settings('chgrp'),
        '#description' => t('If you enter a value here, backup files will be chgrped to the group you specify. Leave blank to disable this feature.'),
      );
    }
    return $form;
  }

  /**
   * Validate the form for the settings for the files destination.
   */
  function edit_form_validate($form, &$form_state) {
    $values = $form_state['values'];
    if (isset($values['settings']['chmod']) && !empty($values['settings']['chmod']) && !preg_match('/0?[0-7]{3}/', $values['settings']['chmod'])) {
      form_set_error('chmod', t('You must enter a valid chmod octal value (e.g. 644 or 0644) in the change mode field, or leave it blank.'));
    }
    parent::edit_form_validate($form, $form_state);
  }

  /**
   * Submit the form for the settings for the files destination.
   */
  function edit_form_submit($form, &$form_state) {
    // Add a 0 to the start of a 3 digit file mode to make it proper PHP encoded octal.
    if (strlen($form_state['values']['settings']['chmod']) == 3) {
      $form_state['values']['settings']['chmod'] = '0' . $form_state['values']['settings']['chmod'];
    }
    parent::edit_form_submit($form, $form_state);
  }

  /**
   * Prepare the destination directory for the backups.
   */
  function check_dir($directory) {
    if (!file_prepare_directory($directory, FILE_CREATE_DIRECTORY)) {
      // Unable to create destination directory.
      _backup_migrate_message("Unable to create or write to the save directory '%directory'. Please check the file permissions that directory and try again.", array('%directory' => $directory), "error");
      return FALSE;
    }
    // If the destination directory is within the webroot, then secure it as best we can.
    if ($this->dir_in_webroot($directory)) {
      $directory = $this->check_web_dir($directory);
    }

    return $directory;
  }

  /**
   * Check that a web accessible directory has been properly secured, othewise attempt to secure it.
   */
  function check_web_dir($directory) {
    file_create_htaccess($directory, TRUE);

    // Check the user agent to make sure we're not responding to a request from drupal itself.
    // That should prevent infinite loops which could be caused by poormanscron in some circumstances.
    if (strpos($_SERVER['HTTP_USER_AGENT'], 'Drupal') !== FALSE) {
      return FALSE;
    }

    // Check to see if the destination is publicly accessible
    $test_contents = "this file should not be publicly accessible";
    // Create the the text.txt file if it's not already there.
    if (!is_file($directory .'/test.txt') || file_get_contents($directory .'/test.txt') != $test_contents) {
      if ($fp = fopen($directory .'/test.txt', 'w')) {
        @fputs($fp, $test_contents);
        fclose($fp);
      }
      else {
        $message = t("Security notice: Backup and Migrate was unable to write a test text file to the destination directory %directory, and is therefore unable to check the security of the backup destination. Backups to the server will be disabled until the destination becomes writable and secure.", array('%directory' => $directory));
        drupal_set_message($message, "error");
        return FALSE;
      }
    }

    // Attempt to read the test file via http. This may fail for other reasons,
    // so it's not a bullet-proof check.
    if ($this->test_file_readable_remotely($directory .'/test.txt', $test_contents)) {
      $message = t("Security notice: Backup and Migrate will not save backup files to the server because the destination directory is publicly accessible. If you want to save files to the server, please secure the '%directory' directory", array('%directory' => $directory));
      drupal_set_message($message, "error");
      return FALSE;
    }
    return $directory;
  }

  /**
   * Check if the given directory is within the webroot and is therefore web accessible.
   */
  function dir_in_webroot($directory) {
    if (strpos(drupal_realpath($directory), realpath($_SERVER['DOCUMENT_ROOT'])) !== FALSE) {
      return TRUE;
    }
    return FALSE;
  }

  /**
   * Check if a file can be read remotely via http.
   */
  function test_file_readable_remotely($path, $contents) {
    $url = file_create_url($path);
    // TODO: Proper checking for absolute paths.
    $result = drupal_http_request($url);
    if (!empty($result->data) && strpos($result->data, $contents) !== FALSE) {
      return TRUE;
    }
    return FALSE;
  }
}

/**
 * The manual files directory.
 */
class backup_migrate_destination_files_manual extends backup_migrate_destination_files {
  var $supported_ops = array('manual backup', 'restore', 'list files', 'configure', 'delete');
  function __construct($params = array()) {
    $dir = 'private://backup_migrate/manual';
    parent::__construct($params + array('location' => $dir, 'name' => t('Manual Backups Directory')));
  }
}

/**
 * The scheduled files directory.
 */
class backup_migrate_destination_files_scheduled extends backup_migrate_destination_files {
  var $supported_ops = array('scheduled backup', 'restore', 'list files', 'configure', 'delete');
  function __construct($params = array()) {
    $dir = 'private://backup_migrate/scheduled';
    parent::__construct($params + array('location' => $dir, 'name' => t('Scheduled Backups Directory')));
  }
}
