Merge "Reland "Add ThermalStatusMonitor to toruslib to monitor system thermal...

/*

 * Copyright (C) 2025 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.

 */

package com.google.android.torus.utils.system

import android.content.Context

import android.os.PowerManager

import android.os.PowerManager.THERMAL_STATUS_SEVERE

import android.util.Log

/** Interface definition for a callback to be invoked when the device's thermal status changes. */

interface ThermalStatusCallback {

    /**

     * Called when the device's thermal status has changed.

     *

     * @param newStatus The new thermal status. This will be one of the

     *   `PowerManager.THERMAL_STATUS_*` constants.

     */

    fun onThermalStatusChanged(newStatus: Int)

}

/**

 * Monitors the device's thermal status and provides callbacks when it changes. This class requires

 * API level 29 (Android Q) or higher to function.

 *

 * @param callback The callback to be invoked when the thermal status changes.

 */

class ThermalStatusMonitor(

    private val context: Context,

    private val callback: ThermalStatusCallback,

) : PowerManager.OnThermalStatusChangedListener {

    private val powerManager: PowerManager? by lazy {

        context.getSystemService(Context.POWER_SERVICE) as PowerManager?

    }

    private var currentThermalStatus: Int = PowerManager.THERMAL_STATUS_NONE

    private var isListenerRegistered: Boolean = false

    /** If the listener is already registered, this method does nothing. */

    fun startMonitoring() {

        if (powerManager == null) {

            Log.w(TAG, "Failed to start monitoring. Power manager is null")

            return

        }

        if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.Q) {

            if (!isListenerRegistered) {

                powerManager!!.addThermalStatusListener(this)

                Log.d(TAG, "Thermal status monitoring started.")

                currentThermalStatus = powerManager!!.currentThermalStatus

                callback.onThermalStatusChanged(currentThermalStatus)

                isListenerRegistered = true

            } else {

                Log.d(TAG, "Thermal status listener already registered.")

            }

        } else {

            Log.w(TAG, "Thermal API (API 29+) not available on this device. Monitoring skipped.")

        }

    }

    /** If the listener is not currently registered, this method does nothing. */

    fun stopMonitoring() {

        if (powerManager == null) {

            Log.w(TAG, "Failed to stop monitoring. Power manager is null")

            return

        }

        if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.Q) {

            if (isListenerRegistered) {

                powerManager!!.removeThermalStatusListener(this)

                Log.d(TAG, "Thermal status monitoring stopped.")

                isListenerRegistered = false

            } else {

                Log.d(TAG, "This thermal status listener hasn't been registered.")

            }

        }

    }

    /**

     * Checks if the current thermal status is [PowerManager.THERMAL_STATUS_SEVERE] or higher.

     *

     * @return `true` if the current thermal status is severe or critical, `false` otherwise.

     */

    fun isSevereOrHigher(): Boolean {

        return currentThermalStatus >= THERMAL_STATUS_SEVERE

    }

    /**

     * Callback method invoked by the system when the thermal status changes. This method updates

     * the [currentThermalStatus] and notifies the registered [ThermalStatusCallback].

     */

    override fun onThermalStatusChanged(status: Int) {

        Log.d(TAG, "Thermal status changed from $currentThermalStatus to $status")

        currentThermalStatus = status

        callback.onThermalStatusChanged(status)

    }

    companion object {

        private const val TAG = "ThermalStatusMonitor"

    }

}