// Copyright 2015 The Chromium OS Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef THERMALD_THERMAL_ZONE_CONTROLLER_H_
#define THERMALD_THERMAL_ZONE_CONTROLLER_H_

#include <memory>
#include <string>
#include <vector>

#include "base/macros.h"
#include "base/memory/weak_ptr.h"

#include "thermald/key_value_publisher.h"
#include "thermald/temperature_monitor_interface.h"
#include "thermald/thermal_state_engine.h"
#include "thermald/thermal_zone.h"

namespace thermald {

// Controls the temperature of a thermal zone. Subscribes to the temperature
// monitors of the zone and processes notifications about temperature
// updates. Uses a thermal state machine object to determine the current
// thermal state of the zone. When a new state is entered it sets the output
// values corresponding to this state.
class ThermalZoneController {
 public:
  // Does not take ownership of the thermal zone and the temperature monitors.
  // The caller must ensure that these objects are valid during the lifetime
  // of the thermal zone controller.
  ThermalZoneController(
      const ThermalZone *zone,
      KeyValuePublisher *output_values,
      std::vector<TemperatureMonitorInterface *> temperature_monitors);

  ~ThermalZoneController();

  // Starts monitoring of the temperatures of the thermal zone.
  // Subscribes to temperature monitors of the zone. Thermal outputs are
  // published using the KeyValuePublisher passed in the constructor until
  // Stop() is called. Returns true on success or false if the controller is
  // already running.
  bool Start();

  // Stops monitoring of the temperatures of the thermal zone.
  // Returns true on success or false if the controller is not running.
  bool Stop();

 private:
  friend class ThermalZoneControllerTest;

  // Processes a temperature update. If the thermal state of the zone has
  // changed it sets the outputs corresponding to the new state.
  void ProcessTemperatureUpdate(const std::string &sensor, int temperature);

  const ThermalZone *zone_;
  std::vector<TemperatureMonitorInterface *> temperature_monitors_;
#if BASE_VER < 860220
  std::vector<std::unique_ptr<TemperatureMonitorInterface::Subscription>>
      subscriptions_;
#else
  std::vector<base::CallbackListSubscription> subscriptions_;
#endif
  bool is_running_;
  ThermalStateEngine thermal_state_engine_;
  const ThermalState *cur_thermal_state_;
  KeyValuePublisher *outputs_;
  base::WeakPtrFactory<ThermalZoneController> weak_ptr_factory_;

  DISALLOW_COPY_AND_ASSIGN(ThermalZoneController);
};

}  // namespace thermald

#endif  // THERMALD_THERMAL_ZONE_CONTROLLER_H_