/*
 * Copyright (C) 2022 The Android Open Source Project
 *
 * Licensed 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.
 */

#pragma once

#include <aidl/android/hardware/thermal/Temperature.h>

#include <functional>
#include <queue>
#include <set>
#include <shared_mutex>
#include <string>
#include <unordered_map>
#include <unordered_set>

#include "power_files.h"
#include "thermal_info.h"
#include "thermal_stats_helper.h"

namespace aidl {
namespace android {
namespace hardware {
namespace thermal {
namespace implementation {

struct ThermalThrottlingStatus {
    std::unordered_map<std::string, int> pid_power_budget_map;
    std::unordered_map<std::string, int> pid_cdev_request_map;
    std::unordered_map<std::string, int> hardlimit_cdev_request_map;
    std::unordered_map<std::string, int> throttling_release_map;
    std::unordered_map<std::string, int> cdev_status_map;
    float prev_err;
    float i_budget;
    float prev_target;
    float prev_power_budget;
    float budget_transient;
    int tran_cycle;
    std::string profile;
};

// Return the control temp target of PID algorithm
size_t getTargetStateOfPID(const SensorInfo &sensor_info, const ThrottlingSeverity curr_severity);

// A helper class for conducting thermal throttling
class ThermalThrottling {
  public:
    ThermalThrottling() = default;
    ~ThermalThrottling() = default;
    // Disallow copy and assign.
    ThermalThrottling(const ThermalThrottling &) = delete;
    void operator=(const ThermalThrottling &) = delete;

    // Clear throttling data
    void clearThrottlingData(std::string_view sensor_name);
    // Register map for throttling algo
    bool registerThermalThrottling(
            std::string_view sensor_name, const std::shared_ptr<ThrottlingInfo> &throttling_info,
            const std::unordered_map<std::string, CdevInfo> &cooling_device_info_map);
    // Get throttling status map
    const std::unordered_map<std::string, ThermalThrottlingStatus> &GetThermalThrottlingStatusMap()
            const {
        std::shared_lock<std::shared_mutex> _lock(thermal_throttling_status_map_mutex_);
        return thermal_throttling_status_map_;
    }
    // Update thermal throttling request for the specific sensor
    void thermalThrottlingUpdate(
            const Temperature &temp, const SensorInfo &sensor_info,
            const ThrottlingSeverity curr_severity, const std::chrono::milliseconds time_elapsed_ms,
            const std::unordered_map<std::string, PowerStatus> &power_status_map,
            const std::unordered_map<std::string, CdevInfo> &cooling_device_info_map,
            const bool max_throttling = false,
            const std::vector<float> &sensor_predictions = std::vector<float>{});

    // Compute the throttling target from all the sensors' request
    void computeCoolingDevicesRequest(std::string_view sensor_name, const SensorInfo &sensor_info,
                                      const ThrottlingSeverity curr_severity,
                                      std::vector<std::string> *cooling_devices_to_update,
                                      ThermalStatsHelper *thermal_stats_helper);
    // Get the aggregated (from all sensor) max request for a cooling device
    bool getCdevMaxRequest(std::string_view cdev_name, int *max_state);

  private:
    // Check if the thermal throttling profile need to be switched
    void parseProfileProperty(std::string_view sensor_name, const SensorInfo &sensor_info);
    // PID algo - get the total power budget
    float updatePowerBudget(
            const Temperature &temp, const SensorInfo &sensor_info,
            const std::unordered_map<std::string, CdevInfo> &cooling_device_info_map,
            std::chrono::milliseconds time_elapsed_ms, ThrottlingSeverity curr_severity,
            const bool max_throttling,
            const std::vector<float> &sensor_predictions = std::vector<float>{});

    // PID algo - return the power number from excluded power rail list
    float computeExcludedPower(const SensorInfo &sensor_info,
                               const ThrottlingSeverity curr_severity,
                               const std::unordered_map<std::string, PowerStatus> &power_status_map,
                               std::string *log_buf, std::string_view sensor_name);

    // PID algo - allocate the power to target CDEV according to the ODPM
    bool allocatePowerToCdev(
            const Temperature &temp, const SensorInfo &sensor_info,
            const ThrottlingSeverity curr_severity, const std::chrono::milliseconds time_elapsed_ms,
            const std::unordered_map<std::string, PowerStatus> &power_status_map,
            const std::unordered_map<std::string, CdevInfo> &cooling_device_info_map,
            const bool max_throttling, const std::vector<float> &sensor_predictions);
    // PID algo - map the target throttling state according to the power budget
    void updateCdevRequestByPower(
            std::string sensor_name,
            const std::unordered_map<std::string, CdevInfo> &cooling_device_info_map);
    // Hard limit algo - assign the throttling state according to the severity
    void updateCdevRequestBySeverity(std::string_view sensor_name, const SensorInfo &sensor_info,
                                     ThrottlingSeverity curr_severity);
    // Throttling release algo - decide release step according to the predefined power threshold,
    // return false if the throttling release is not registered in thermal config
    bool throttlingReleaseUpdate(
            std::string_view sensor_name,
            const std::unordered_map<std::string, CdevInfo> &cooling_device_info_map,
            const std::unordered_map<std::string, PowerStatus> &power_status_map,
            const ThrottlingSeverity severity, const SensorInfo &sensor_info);
    // Update the cooling device request set for new request and notify the caller if there is
    // change in max_request for the cooling device.
    bool updateCdevMaxRequestAndNotifyIfChange(std::string_view cdev_name, int cur_request,
                                               int new_request);
    mutable std::shared_mutex thermal_throttling_status_map_mutex_;
    // Thermal throttling status from each sensor
    std::unordered_map<std::string, ThermalThrottlingStatus> thermal_throttling_status_map_;
    std::shared_mutex cdev_all_request_map_mutex_;
    // Set of all request for a cooling device from each sensor
    std::unordered_map<std::string, std::multiset<int, std::greater<int>>> cdev_all_request_map_;
};

}  // namespace implementation
}  // namespace thermal
}  // namespace hardware
}  // namespace android
}  // namespace aidl