// Copyright 2018 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef ASH_ASSISTANT_MODEL_ASSISTANT_NOTIFICATION_MODEL_H_
#define ASH_ASSISTANT_MODEL_ASSISTANT_NOTIFICATION_MODEL_H_

#include <map>
#include <string>
#include <vector>

#include "base/component_export.h"
#include "base/observer_list.h"
#include "chromeos/ash/services/libassistant/public/cpp/assistant_notification.h"

namespace ash {

class AssistantNotificationModelObserver;

// The model belonging to AssistantNotificationController which tracks
// notification state and notifies a pool of observers.
class COMPONENT_EXPORT(ASSISTANT_MODEL) AssistantNotificationModel {
 public:
  using AssistantNotification = assistant::AssistantNotification;

  AssistantNotificationModel();

  AssistantNotificationModel(const AssistantNotificationModel&) = delete;
  AssistantNotificationModel& operator=(const AssistantNotificationModel&) =
      delete;

  ~AssistantNotificationModel();

  // Adds/removes the specified notification model |observer|.
  void AddObserver(AssistantNotificationModelObserver* observer) const;
  void RemoveObserver(AssistantNotificationModelObserver* observer) const;

  // Adds or updates the specified |notification| in the model. If there is an
  // existing notification with the same |client_id|, an update will occur.
  // Otherwise a new notification will be added.
  void AddOrUpdateNotification(AssistantNotification&& notification);

  // Removes the notification uniquely identified by |id|. If |from_server| is
  // true the request to remove was initiated by the server.
  void RemoveNotificationById(const std::string& id, bool from_server);

  // Removes the notifications identified by |grouping_key|. If |from_server| is
  // true the request to remove was initiated by the server.
  void RemoveNotificationsByGroupingKey(const std::string& grouping_key,
                                        bool from_server);

  // Removes all notifications. If |from_server| is true the request to remove
  // was initiated by the server.
  void RemoveAllNotifications(bool from_server);

  // Returns the notification uniquely identified by |id|.
  const AssistantNotification* GetNotificationById(const std::string& id) const;

  // Returns all notifications (that have not been removed).
  std::vector<const AssistantNotification*> GetNotifications() const;

  // Returns true if the model contains a notification uniquely identified by
  // |id|, otherwise false.
  bool HasNotificationForId(const std::string& id) const;

 private:
  void NotifyNotificationAdded(const AssistantNotification& notification);
  void NotifyNotificationUpdated(const AssistantNotification& notification);
  void NotifyNotificationRemoved(const AssistantNotification& notification,
                                 bool from_server);
  void NotifyAllNotificationsRemoved(bool from_server);

  // Notifications are each mapped to their unique id.
  std::map<std::string, AssistantNotification> notifications_;

  mutable base::ObserverList<AssistantNotificationModelObserver> observers_;
};

}  // namespace ash

#endif  // ASH_ASSISTANT_MODEL_ASSISTANT_NOTIFICATION_MODEL_H_