/*
 * Copyright (C) 2017 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.googlecode.android_scripting.facade;

import android.content.Context;
import android.os.PowerManager;
import android.os.PowerManager.WakeLock;

import com.googlecode.android_scripting.jsonrpc.RpcReceiver;
import com.googlecode.android_scripting.rpc.Rpc;

import java.util.HashMap;
import java.util.Map;
import java.util.Map.Entry;

/**
 * A facade exposing some of the functionality of the PowerManager, in particular wake locks.
 *
 */
public class WakeLockFacade extends RpcReceiver {

    private final static String WAKE_LOCK_TAG =
            "com.googlecode.android_scripting.facade.PowerManagerFacade";
    private final PowerManager mmPowerManager;

    private enum WakeLockType {
        FULL, PARTIAL, BRIGHT, DIM
    }

    private class WakeLockManager {
        private final Map<WakeLockType, WakeLock> mmLocks = new HashMap<WakeLockType, WakeLock>();

        public WakeLockManager(PowerManager mmPowerManager) {
            addWakeLock(WakeLockType.PARTIAL, PowerManager.PARTIAL_WAKE_LOCK);
            addWakeLock(WakeLockType.FULL, PowerManager.FULL_WAKE_LOCK
                    | PowerManager.ON_AFTER_RELEASE);
            addWakeLock(WakeLockType.BRIGHT, PowerManager.SCREEN_BRIGHT_WAKE_LOCK
                    | PowerManager.ON_AFTER_RELEASE);
            addWakeLock(WakeLockType.DIM, PowerManager.SCREEN_DIM_WAKE_LOCK
                    | PowerManager.ON_AFTER_RELEASE);
        }

        private void addWakeLock(WakeLockType type, int flags) {
            WakeLock full = mmPowerManager.newWakeLock(flags, WAKE_LOCK_TAG);
            full.setReferenceCounted(false);
            mmLocks.put(type, full);
        }

        public void acquire(WakeLockType type) {
            mmLocks.get(type).acquire();
            for (Entry<WakeLockType, WakeLock> entry : mmLocks.entrySet()) {
                if (entry.getKey() != type) {
                    entry.getValue().release();
                }
            }
        }

        public void release() {
            for (Entry<WakeLockType, WakeLock> entry : mmLocks.entrySet()) {
                entry.getValue().release();
            }
        }
    }

    private final WakeLockManager mManager;

    public WakeLockFacade(FacadeManager manager) {
        super(manager);
        mmPowerManager = (PowerManager) manager.getService()
                .getSystemService(Context.POWER_SERVICE);
        mManager = new WakeLockManager(mmPowerManager);
    }

    @Rpc(description = "Acquires a full wake lock (CPU on, screen bright, keyboard bright).")
    public void wakeLockAcquireFull() {
        mManager.acquire(WakeLockType.FULL);
    }

    @Rpc(description = "Acquires a partial wake lock (CPU on).")
    public void wakeLockAcquirePartial() {
        mManager.acquire(WakeLockType.PARTIAL);
    }

    @Rpc(description = "Acquires a bright wake lock (CPU on, screen bright).")
    public void wakeLockAcquireBright() {
        mManager.acquire(WakeLockType.BRIGHT);
    }

    @Rpc(description = "Acquires a dim wake lock (CPU on, screen dim).")
    public void wakeLockAcquireDim() {
        mManager.acquire(WakeLockType.DIM);
    }

    @Rpc(description = "Releases the wake lock.")
    public void wakeLockRelease() {
        mManager.release();
    }

    @Override
    public void shutdown() {
        wakeLockRelease();
    }
}