/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "nsISupports.idl"

interface mozIStorageConnection;
interface nsIActivity;
interface nsIActivityProcess;
interface nsIVariant;

/**
 * See https://wiki.mozilla.org/Thunderbird:Activity_Manager/Developer for UML
 * diagram and sample codes.
 */

/**
 * An interface to get notified by the major Activity Manager events.
 * Mostly used by UI glue code in activity.js.
 */
[scriptable, uuid(14cfad1c-3401-4c44-ab04-4a11b6662663)]
interface nsIActivityMgrListener : nsISupports {
  /**
   * Called _after_ activity manager adds an activity into
   * the managed list.
   */
  void onAddedActivity(in unsigned long aID, in nsIActivity aActivity);
  
  /**
   * Called _after_ activity manager removes an activity from
   * the managed list.
   */
  void onRemovedActivity(in unsigned long aID);
};

/**
 * Activity Manager is a simple component that understands how do display a
 * combination of user activity and history. The activity manager works in
 * conjunction with the 'Interactive Status Bar' to give the user the right
 * level of notifications concerning what Thunderbird is doing on it's own and
 * how Thunderbird has handled user requests.
 *
 * There are 3 different classifications of activity items which can be
 * displayed in the Activity Manager Window:
 *  o Process: Processes are transient in the display. They are not written to
 *    disk as they are always acting on some data that already exists
 *    locally or remotely. If a process has finished and needs to keep
 *    some state for the user (like last sync time) it can convert
 *    itself into an event.
 * o Event: Historical actions performed by the user and created by a process
 *   for the Activity Manager Window. Events can show up in the
 *   'Interactive Status Bar' and be displayed to users as they are
 *   created.
 * o Warning: Alerts sent by Thunderbird or servers (i.e. imap server) that need
 *   attention by the user. For example a Quota Alert from the imap
 *   server can be represented as a Warning to the user. They are not
 *   written to disk.
 */
[scriptable, uuid(9BFCC031-50E1-4D30-A35F-23509ABCB8D1)]
interface nsIActivityManager : nsISupports {
    
  /**
   * Adds the given activity into the managed activities list.
   *
   * @param aActivity The activity that will be added.
   *
   * @return Unique activity identifier.
   */
  unsigned long addActivity(in nsIActivity aActivity);
  
  /**
   * Removes the activity with the given id if it's not currently
   * in-progress.
   *
   * @param aID The unique ID of the activity.
   *
   * @throws NS_ERROR_FAILURE if the activity is in-progress.
   * @throws NS_ERROR_NOT_AVAILABLE if the activity is not in the list.
   */
  void removeActivity(in unsigned long aID);

  /**
   * Retrieves an activity managed by the activity manager. This can be one that
   * is in progress, or one that has completed in the past and is stored in the
   * persistent store.
   *
   * @param aID The unique ID of the activity.
   *
   * @return The activity with the specified ID.
   * @throws NS_ERROR_NOT_AVAILABLE if the activity is not in the list.
   */
  nsIActivity getActivity(in unsigned long aID);
  
  /**
   * Tests wether the activity in question in the activity list or not.
   */
  boolean containsActivity(in unsigned long aID);
  
  /**
   * Retrieves all activities managed by the activity manager. This can be one
   * that is in progress (process), one that is represented as a warning, or one
   * that has completed (event) in the past and is stored in the persistent
   * store.
   *
   * @return A read-only list of activities managed by the activity manager.
   */
  void getActivities(out unsigned long length,
                  [retval, array, size_is(length)] out nsIActivity aActivities);
  
  /**
   * Retrieves processes with given context type and object.
   *
   * @return A read-only list of processes matching to given criteria.
   */
  void getProcessesByContext(in AString aContextType,
                             in nsIVariant aContextObject,
                             out unsigned long length,
                             [retval, array, size_is(length)] out nsIActivityProcess aProcesses);

  /**
   *  Call to remove all activities apart from those that are in progress.
   */
  void cleanUp();

  /**
   * The number of processes in the activity list.
   */
  readonly attribute long processCount;
  
  /**
   * Adds a listener.
   */
  void addListener(in nsIActivityMgrListener aListener);

  /**
   * Removes the given listener.
   */
  void removeListener(in nsIActivityMgrListener aListener);
};