/**
  * 削除メッセージ操作
  *
  * @return boolean	true or false
  * @access	public
  */
 function deleteMessage()
 {
     $receiver_id = $this->_request->getParameter("receiver_id");
     if (!is_array($receiver_id)) {
         $receivers = explode(" ", $receiver_id);
     } else {
         $receivers = $receiver_id;
     }
     if (!is_array($receivers)) {
         return false;
     }
     $dropped_messages = array();
     foreach ($receivers as $receiver) {
         $message = $this->_pmView->getMessage($receiver);
         if ($message["delete_state"] == PM_MESSAGE_STATE_TRASH) {
             $delete_state = PM_MESSAGE_STATE_DELETE;
             $message_id = $message["message_id"];
             // メッセージ削除処理
             $deleteParams = array("receiver_id" => $receiver);
             // タグ設定情報削除
             if (!$this->_db->deleteExecute("pm_message_tag_link", $deleteParams)) {
                 $this->_db->addError();
             }
             // 受信人メッセージ情報削除
             if (!$this->_db->deleteExecute("pm_message_receiver", $deleteParams)) {
                 $this->_db->addError();
             }
             if ($this->_pmView->isDropedMessage($message_id, false)) {
                 $dropped_messages[] = $message_id;
             }
         } else {
             $delete_state = PM_MESSAGE_STATE_TRASH;
             // 更新受信人メッセージ情報の受信人メッセージ状態
             $updateParams = array("receiver_id" => $receiver, "delete_state" => $delete_state);
             if (!$this->_db->updateExecute("pm_message_receiver", $updateParams, "receiver_id", true)) {
                 return false;
             }
         }
     }
     if (sizeof($dropped_messages) > 0) {
         $pm_delete_upload_ids = array();
         foreach ($dropped_messages as $dropped_message_id) {
             $deleteParams = array("message_id" => $dropped_message_id);
             // メッセージ情報削除
             if (!$this->_db->deleteExecute("pm_message", $deleteParams)) {
                 $this->_db->addError();
             }
             // Upload情報削除
             $getdata =& $this->_container->getComponent("GetData");
             $modules = $getdata->getParameter("modules");
             $module_id = $modules["pm"]["module_id"];
             $upload_id = $this->_pmView->getUploadId($module_id, $dropped_message_id);
             if ($upload_id != false) {
                 $pm_delete_upload_ids[] = $upload_id;
             }
         }
         if (sizeof($pm_delete_upload_ids) > 0) {
             $this->_session->setParameter("pm_delete_upload_ids", $pm_delete_upload_ids);
         }
     }
     return true;
 }