$data";
    } else {
      $proc = proc_open("/usr/bin/dot -Tsvg",
                        array(array("pipe", "r"),
                              array("pipe", "w")),
                        $pipes,
                        VARPATH . "tmp");
      fwrite($pipes[0], $data);
      fclose($pipes[0]);

      header("Content-Type: image/svg+xml");
      print(stream_get_contents($pipes[1]));
      fclose($pipes[1]);
      proc_close($proc);
    }
  }

  function i18n($action) {
    $translation_file = VARPATH . "translation.php";

    switch($action) {
    case "build":
      $t = array();
      for ($i = 0; $i < 500; $i++) {
        $t["this is message $i of many"] = "localized version of $i";
      }

      $fp = fopen($translation_file, "wb");
      fwrite($fp, "auto_render = false;
    }
  }

  function add_albums_and_photos($count) {
    srand(time());
    $parents = ORM::factory("item")->where("type", "album")->find_all()->as_array();

    try {
      $user = Session::instance()->get("user");
      $owner_id = $user ? $user->id : ORM::factory("user")->find()->id;
    } catch (Exception $e) {
      $owner_id = null;
    }

    for ($i = 0; $i < $count; $i++) {
      $parent = $parents[array_rand($parents)];
      if (!rand(0, 10)) {
        $parents[] = album::create(
          $parent->id, "rnd_" . rand(), "Rnd $i", "random album $i", $owner_id)
          ->set_thumbnail(DOCROOT . "core/tests/test.jpg", 200, 150)
          ->save();
      } else {
        photo::create($parent->id, DOCROOT . "themes/default/images/thumbnail.jpg",
                      "thumbnail.jpg", "rnd_" . rand(), "sample thumbnail", $owner_id);
      }

      if (!($i % 100)) {
        set_time_limit(30);
      }
    }
    url::redirect("welcome");
  }

  function add_comments($count) {
    $photos = ORM::factory("item")->where("type", "photo")->find_all()->as_array();

    $sample_text = "Sed ut perspiciatis, unde omnis iste natus error sit voluptatem accusantium
      doloremque laudantium, totam rem aperiam eaque ipsa, quae ab illo inventore veritatis et quasi
      architecto beatae vitae dicta sunt, explicabo. Nemo enim ipsam voluptatem, quia voluptas
      sit, aspernatur aut odit aut fugit, sed quia consequuntur magni dolores eos, qui ratione
      voluptatem sequi nesciunt, neque porro quisquam est, qui dolorem ipsum, quia dolor sit,
      amet, consectetur, adipisci velit, sed quia non numquam eius modi tempora incidunt, ut
      labore et dolore magnam aliquam quaerat voluptatem. Ut enim ad minima veniam, quis nostrum
      exercitationem ullam corporis suscipit laboriosam, nisi ut aliquid ex ea commodi
      consequatur? Quis autem vel eum iure reprehenderit, qui in ea voluptate velit esse, quam
      nihil molestiae consequatur, vel illum, qui dolorem eum fugiat, quo voluptas nulla pariatur?
      At vero eos et accusamus et iusto odio dignissimos ducimus, qui blanditiis praesentium
      voluptatum deleniti atque corrupti, quos dolores et quas molestias excepturi sint, obcaecati
      cupiditate non provident, similique sunt in culpa, qui officia deserunt mollitia animi, id
      est laborum et dolorum fuga. Et harum quidem rerum facilis est et expedita distinctio. Nam
      libero tempore, cum soluta nobis est eligendi optio, cumque nihil impedit, quo minus id,
      quod maxime placeat, facere possimus, omnis voluptas assumenda est, omnis dolor repellendus.
      Temporibus autem quibusdam et aut officiis debitis aut rerum necessitatibus saepe eveniet,
      ut et voluptates repudiandae sint et molestiae non recusandae. Itaque earum rerum hic
      tenetur a sapiente delectus, ut aut reiciendis voluptatibus maiores alias consequatur aut
      perferendis doloribus asperiores repellat.";

    if (empty($photos)) {
      url::redirect("welcome");
    }

    for ($i = 0; $i < $count; $i++) {
      $photo = $photos[array_rand($photos)];
      comment::create("John Doe", "johndoe@example.com",
        substr($sample_text, 0, rand(30, strlen($sample_text))), $photo->id,
        time() - rand(0, 2 * comment::SECONDS_IN_A_YEAR));
    }

    url::redirect("welcome");
  }

  function add_tags($count) {
    $items = ORM::factory("item")->find_all()->as_array();

    if (!empty($items)) {
      $tags = $this->_generateTags($count);

      while ($count-- > 0) {
        $tag_name = $tags[array_rand($tags)];
        $item = $items[array_rand($items)];

        tag::add($item, $tag_name);
      }
    }

    url::redirect("welcome");
  }

  private function _generateTags($number){

    list($usec, $sec) = explode(' ', microtime());
    srand((float) $sec + ((float) $usec * 100000));

    $validchars = "0123456789abcdfghjkmnpqrstvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";

    $tags = array();

    for ($tag_count = 0; $tag_count < $number; $tag_count++) {
      $tag  = "";
      $tag_length = rand(3, 16);
      for ($counter  = 0; $counter < $tag_length; $counter++) {
        $tag .= substr($validchars, rand(0, strlen($validchars)-1), 1);;
      }
      $tags[] = $tag;
   }

    return $tags;
  }

  public function session($key) {
    Session::instance()->set($key, $this->input->get("value", false));
    $this->auto_render = false;
    url::redirect("welcome");
  }

  private function _get_config_errors() {
    $errors = array();
    if (!file_exists(VARPATH)) {
      $error = new stdClass();
      $error->message = "Missing: " . VARPATH;
      $error->instructions[] = "mkdir " . VARPATH;
      $error->instructions[] = "chmod 777 " . VARPATH;
      $errors[] = $error;
    } else if (!is_writable(VARPATH)) {
      $error = new stdClass();
      $error->message = "Not writable: " . VARPATH;
      $error->instructions[] = "chmod 777 " . VARPATH;
      $errors[] = $error;
    }

    $db_php = VARPATH . "database.php";
    if (!file_exists($db_php)) {
      $error = new stdClass();
      $error->message = "Missing: $db_php 
 Run the following commands...";
      $error->instructions[] = "cp " . DOCROOT . "kohana/config/database.php $db_php";
      $error->instructions[] = "chmod 644 $db_php";
      $error->message2 = "...then edit this file and enter your database configuration settings.";
      $errors[] = $error;
    } else if (!is_readable($db_php)) {
      $error = new stdClass();
      $error->message = "Not readable: $db_php";
      $error->instructions[] = "chmod 644 $db_php";
      $error->message2 = "Then edit this file and enter your database configuration settings.";
      $errors[] = $error;
    } else {
      $old_handler = set_error_handler(array("Welcome_Controller", "_error_handler"));
      try {
        Database::instance()->connect();
      } catch (Exception $e) {
        $error = new stdClass();
        $error->message = "Database error: {$e->getMessage()}";
        $db_name = Kohana::config("database.default.connection.database");
        if (strchr($error->message, "Unknown database")) {
          $error->instructions[] = "mysqladmin -uroot create $db_name";
        } else {
          $error->instructions = array();
          $error->message2 = "Check " . VARPATH . "database.php";
        }
        $errors[] = $error;
      }
      set_error_handler($old_handler);
    }

    return $errors;
  }

  function _error_handler($x) {
  }

  function _create_directories() {
    foreach (array("logs") as $dir) {
      @mkdir(VARPATH . "$dir");
    }
  }

  /**
   * Create an array of all the modules that are install or available and the version number
   * @return array(moduleId => version)
   */
  private function _read_modules() {
    $modules = array();
    try {
      $installed = ORM::factory("module")->find_all();
      foreach ($installed as $installed_module) {
        $modules[$installed_module->name] = $installed_module->version;
      }

      foreach (glob(MODPATH . "*/helpers/*_installer.php") as $file) {
        if (empty($modules[basename(dirname(dirname($file)))])) {
          $modules[basename(dirname(dirname($file)))] = 0;
        }
      }
    } catch (Exception $e) {
      // The database may not be installed
    }
    ksort($modules);
    return $modules;
  }

  private function _load_group_info() {
    try {
      $this->template->groups = ORM::factory("group")->find_all();
    } catch (Exception $e) {
      $this->template->groups = array();
    }
  }

  private function _load_user_info() {
    try {
      $this->template->users = ORM::factory("user")->find_all();
    } catch (Exception $e) {
      $this->template->users = array();
    }
  }

  private function _load_comment_info() {
    try {
      $this->template->comment_count = ORM::factory("comment")->count_all();
    } catch (Exception $e) {
      $this->template->comment_count = 0;
    }
  }

  private function _load_tag_info() {
    try {
      $this->template->tag_count = ORM::factory("tag")->count_all();
      $this->template->most_tagged = Database::instance()
        ->select("item_id AS id", "COUNT(tag_id) AS count")
        ->from("items_tags")
        ->groupby("item_id")
        ->orderby("count", "DESC")
        ->limit(1)
        ->get()
        ->current();
    } catch (Exception $e) {
      $this->template->tag_count = 0;
      $this->template->most_tagged = 0;
    }
  }

  public function add_user() {
    $name = $this->input->post("user_name");
    $user = ORM::factory("user");
    $user->name = $name;
    $user->display_name = $name;
    $user->password = $name;
    $user->save();
    url::redirect("welcome");
  }

  public function delete_user($name) {
    ORM::factory("user")->where("name", $name)->find()->delete();
    url::redirect("welcome");
  }

  public function add_group() {
    $name = $this->input->post("group_name");
    $group = ORM::factory("group");
    $group->name = $name;
    $group->save();
    url::redirect("welcome");
  }

  public function delete_group($name) {
    ORM::factory("group")->where("name", $name)->find()->delete();
    url::redirect("welcome");
  }

}