/**
 *
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
#ifndef LIBMINIFI_INCLUDE_CONTROLLERS_LINUXPOWERMANAGEMENTSERVICE_H_
#define LIBMINIFI_INCLUDE_CONTROLLERS_LINUXPOWERMANAGEMENTSERVICE_H_

#include <iostream>
#include <memory>
#include "core/Resource.h"
#include "utils/StringUtils.h"
#include "io/validation.h"
#include "core/controller/ControllerService.h"
#include "core/logging/LoggerConfiguration.h"
#include "ThreadManagementService.h"

namespace org {
namespace apache {
namespace nifi {
namespace minifi {
namespace controllers {

/**
 * Purpose: Linux power management service uses a path for the battery level
 * and the status ( charging/discharging )
 */
class LinuxPowerManagerService : public ThreadManagementService {
 public:
  explicit LinuxPowerManagerService(const std::string &name, const std::string &id)
      : ThreadManagementService(name, id),
        enabled_(false),
        battery_level_(0),
        wait_period_(0),
        last_time_(0),
        trigger_(0),
        low_battery_trigger_(0),
        logger_(logging::LoggerFactory<LinuxPowerManagerService>::getLogger()) {
  }

  explicit LinuxPowerManagerService(const std::string &name, uuid_t uuid = 0)
      : ThreadManagementService(name, uuid),
        enabled_(false),
        battery_level_(0),
        wait_period_(0),
        last_time_(0),
        trigger_(0),
        low_battery_trigger_(0),
        logger_(logging::LoggerFactory<LinuxPowerManagerService>::getLogger()) {
  }

  explicit LinuxPowerManagerService(const std::string &name, const std::shared_ptr<Configure> &configuration)
      : LinuxPowerManagerService(name, nullptr) {
    setConfiguration(configuration);
    initialize();
  }

  static core::Property BatteryCapacityPath;
  static core::Property BatteryStatusPath;
  static core::Property BatteryStatusDischargeKeyword;
  static core::Property TriggerThreshold;
  static core::Property LowBatteryThreshold;
  static core::Property WaitPeriod;

  /**
   * Helps to determine if the number of tasks will increase the pools above their threshold.
   * @param new_tasks tasks to be added.
   * @return true if above max, false otherwise.
   */
  virtual bool isAboveMax(const int new_tasks);

  /**
   * Returns the max number of threads allowed by all pools
   * @return max threads.
   */
  virtual uint16_t getMaxThreads();

  /**
   * Function based on cooperative multitasking that will tell a caller whether or not the number of threads should be reduced.
   * @return true if threading impacts QOS.
   */
  virtual bool shouldReduce();

  /**
   * Function to indicate to this controller service that we've reduced threads in a threadpool
   */
  virtual void reduce();

  /**
   * Function to help callers identify if they can increase threads.
   * @return true if QOS won't be breached.
   */
  virtual bool canIncrease();

  void initialize();

  void yield();

  bool isRunning();

  bool isWorkAvailable();

  virtual void onEnable();

 protected:

  std::vector<std::pair<std::string, std::string>> paths_;

  bool enabled_;

  std::atomic<int> battery_level_;

  std::atomic<uint64_t> wait_period_;

  std::atomic<uint64_t> last_time_;

  int trigger_;

  int low_battery_trigger_;

  std::string status_keyword_;

 private:
  std::shared_ptr<logging::Logger> logger_;
};

REGISTER_RESOURCE(LinuxPowerManagerService);

} /* namespace controllers */
} /* namespace minifi */
} /* namespace nifi */
} /* namespace apache */
} /* namespace org */

#endif /* LIBMINIFI_INCLUDE_CONTROLLERS_LINUXPOWERMANAGEMENTSERVICE_H_ */