/*
 * Copyright (C) 2014 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.android.systemui.statusbar.policy;

import android.app.AlarmManager;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.UserHandle;

import androidx.annotation.NonNull;

import com.android.systemui.Dumpable;
import com.android.systemui.broadcast.BroadcastDispatcher;
import com.android.systemui.dagger.SysUISingleton;
import com.android.systemui.dagger.qualifiers.Main;
import com.android.systemui.dump.DumpManager;
import com.android.systemui.settings.UserTracker;

import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Date;
import java.util.concurrent.Executor;

import javax.inject.Inject;

/**
 * Implementation of {@link NextAlarmController}
 */
@SysUISingleton
public class NextAlarmControllerImpl extends BroadcastReceiver
        implements NextAlarmController, Dumpable {

    private final ArrayList<NextAlarmChangeCallback> mChangeCallbacks = new ArrayList<>();

    private final UserTracker mUserTracker;
    private AlarmManager mAlarmManager;
    private AlarmManager.AlarmClockInfo mNextAlarm;

    private final UserTracker.Callback mUserChangedCallback =
            new UserTracker.Callback() {
                @Override
                public void onUserChanged(int newUser, @NonNull Context userContext) {
                    updateNextAlarm();
                }
            };

    /**
     */
    @Inject
    public NextAlarmControllerImpl(
            @Main Executor mainExecutor,
            AlarmManager alarmManager,
            BroadcastDispatcher broadcastDispatcher,
            DumpManager dumpManager,
            UserTracker userTracker) {
        dumpManager.registerDumpable("NextAlarmController", this);
        mAlarmManager = alarmManager;
        mUserTracker = userTracker;
        IntentFilter filter = new IntentFilter();
        filter.addAction(AlarmManager.ACTION_NEXT_ALARM_CLOCK_CHANGED);
        broadcastDispatcher.registerReceiver(this, filter, null, UserHandle.ALL);
        mUserTracker.addCallback(mUserChangedCallback, mainExecutor);
        updateNextAlarm();
    }

    @Override
    public void dump(PrintWriter pw, String[] args) {
        pw.print("mNextAlarm=");
        if (mNextAlarm != null) {
            pw.println(new Date(mNextAlarm.getTriggerTime()));
            pw.print("  PendingIntentPkg=");
            if (mNextAlarm.getShowIntent() != null) {
                pw.println(mNextAlarm.getShowIntent().getCreatorPackage());
            } else {
                pw.println("showIntent=null");
            }
        } else {
            pw.println("null");
        }

        pw.println("Registered Callbacks:");
        for (NextAlarmChangeCallback callback : mChangeCallbacks) {
            pw.print("    "); pw.println(callback.toString());
        }
    }

    @Override
    public void addCallback(@NonNull NextAlarmChangeCallback cb) {
        mChangeCallbacks.add(cb);
        cb.onNextAlarmChanged(mNextAlarm);
    }

    @Override
    public void removeCallback(@NonNull NextAlarmChangeCallback cb) {
        mChangeCallbacks.remove(cb);
    }

    public void onReceive(Context context, Intent intent) {
        final String action = intent.getAction();
        if (action.equals(AlarmManager.ACTION_NEXT_ALARM_CLOCK_CHANGED)) {
            updateNextAlarm();
        }
    }

    private void updateNextAlarm() {
        mNextAlarm = mAlarmManager.getNextAlarmClock(mUserTracker.getUserId());
        fireNextAlarmChanged();
    }

    private void fireNextAlarmChanged() {
        ArrayList<NextAlarmChangeCallback> copy = new ArrayList<>(mChangeCallbacks);
        int n = copy.size();
        for (int i = 0; i < n; i++) {
            copy.get(i).onNextAlarmChanged(mNextAlarm);
        }
    }
}