/*
 * Copyright (C) 2020 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.car.settings.bluetooth;

import static android.car.hardware.power.PowerComponent.BLUETOOTH;
import static android.os.UserManager.DISALLOW_BLUETOOTH;
import static android.os.UserManager.DISALLOW_CONFIG_BLUETOOTH;

import static com.android.car.settings.enterprise.EnterpriseUtils.getAvailabilityStatusRestricted;

import android.bluetooth.BluetoothAdapter;
import android.car.drivingstate.CarUxRestrictions;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.content.pm.PackageManager;
import android.os.UserManager;
import android.widget.Toast;

import androidx.annotation.VisibleForTesting;

import com.android.car.settings.R;
import com.android.car.settings.common.ColoredSwitchPreference;
import com.android.car.settings.common.FragmentController;
import com.android.car.settings.common.PowerPolicyListener;
import com.android.car.settings.common.PreferenceController;
import com.android.car.settings.enterprise.EnterpriseUtils;
import com.android.settingslib.bluetooth.LocalBluetoothManager;

/**
 * Enables/disables bluetooth state via SwitchPreference.
 */
public class BluetoothStateSwitchPreferenceController extends
        PreferenceController<ColoredSwitchPreference> {

    private final Context mContext;
    private final IntentFilter mIntentFilter = new IntentFilter(
            BluetoothAdapter.ACTION_STATE_CHANGED);
    private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            int state = intent.getIntExtra(BluetoothAdapter.EXTRA_STATE, BluetoothAdapter.ERROR);
            handleStateChanged(state);
        }
    };
    private final BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
    private LocalBluetoothManager mLocalBluetoothManager;
    private UserManager mUserManager;
    private boolean mUpdating = false;
    private boolean mIsPowerOn = true;

    @VisibleForTesting
    final PowerPolicyListener mPowerPolicyListener;

    public BluetoothStateSwitchPreferenceController(Context context,
            String preferenceKey,
            FragmentController fragmentController,
            CarUxRestrictions uxRestrictions) {
        super(context, preferenceKey, fragmentController, uxRestrictions);
        mContext = context;
        mPowerPolicyListener = new PowerPolicyListener(context, BLUETOOTH,
                isPowerOn -> {
                    mIsPowerOn = isPowerOn;
                    enableSwitchPreference(getPreference(), /* enabled= */ mIsPowerOn);
                });
    }

    @Override
    protected Class<ColoredSwitchPreference> getPreferenceType() {
        return ColoredSwitchPreference.class;
    }

    @Override
    protected void updateState(ColoredSwitchPreference preference) {
        updateSwitchPreference(mBluetoothAdapter.getState() == BluetoothAdapter.STATE_ON
                || mBluetoothAdapter.getState() == BluetoothAdapter.STATE_TURNING_ON);
    }

    @Override
    protected boolean handlePreferenceChanged(ColoredSwitchPreference preference,
            Object newValue) {
        if (mUpdating) {
            return false;
        }
        enableSwitchPreference(preference, /* enabled= */ false);
        boolean bluetoothEnabled = (Boolean) newValue;
        if (bluetoothEnabled) {
            mBluetoothAdapter.enable();
        } else {
            mBluetoothAdapter.disable();
        }
        return true;
    }

    @Override
    protected void onCreateInternal() {
        mUserManager = mContext.getSystemService(UserManager.class);
        mLocalBluetoothManager = BluetoothUtils.getLocalBtManager(mContext);
        if (mLocalBluetoothManager == null) {
            getFragmentController().goBack();
        }
        ColoredSwitchPreference preference = getPreference();
        preference.setContentDescription(
                mContext.getString(R.string.bluetooth_state_switch_content_description));
        preference.setClickableWhileDisabled(true);
        preference.setDisabledClickListener(p -> {
            // This is logic when clicking while disabled:
            // 1. If power is off, then show a toast with the related error message;
            // 2. If restricted by DPM, show a dialog message with the related restriction message;
            // 3. Do nothing otherwise.
            if (!mIsPowerOn) {
                Toast.makeText(getContext(),
                        getContext().getString(R.string.power_component_disabled),
                        Toast.LENGTH_LONG).show();
            } else if (getAvailabilityStatus() == AVAILABLE_FOR_VIEWING) {
                EnterpriseUtils.onClickWhileDisabled(mContext, getFragmentController(),
                        DISALLOW_CONFIG_BLUETOOTH);
            }
        });
    }

    @Override
    protected int getDefaultAvailabilityStatus() {
        if (!mContext.getPackageManager().hasSystemFeature(PackageManager.FEATURE_BLUETOOTH)) {
            return UNSUPPORTED_ON_DEVICE;
        }
        return getAvailabilityStatusRestricted(mContext, DISALLOW_CONFIG_BLUETOOTH);
    }

    @Override
    protected void onStartInternal() {
        mContext.registerReceiver(mReceiver, mIntentFilter);
        mLocalBluetoothManager.setForegroundActivity(mContext);
        handleStateChanged(mBluetoothAdapter.getState());
    }

    @Override
    protected void onResumeInternal() {
        mPowerPolicyListener.handleCurrentPolicy();
    }

    @Override
    protected void onStopInternal() {
        mContext.unregisterReceiver(mReceiver);
        mLocalBluetoothManager.setForegroundActivity(null);
    }

    @Override
    protected void onDestroyInternal() {
        mPowerPolicyListener.release();
    }

    private boolean isUserRestricted() {
        return mUserManager.hasUserRestriction(DISALLOW_BLUETOOTH);
    }

    @VisibleForTesting
    void handleStateChanged(int state) {
        // Set updating state to prevent additional updates while trying to reflect the new
        // adapter state.
        mUpdating = true;
        switch (state) {
            case BluetoothAdapter.STATE_TURNING_ON:
                enableSwitchPreference(getPreference(), /* enabled= */ false);
                updateSwitchPreference(true);
                break;
            case BluetoothAdapter.STATE_ON:
                enableSwitchPreference(getPreference(), /* enabled= */ !isUserRestricted());
                updateSwitchPreference(true);
                break;
            case BluetoothAdapter.STATE_TURNING_OFF:
                enableSwitchPreference(getPreference(), /* enabled= */ false);
                updateSwitchPreference(false);
                break;
            case BluetoothAdapter.STATE_OFF:
            default:
                enableSwitchPreference(getPreference(), /* enabled= */ !isUserRestricted());
                updateSwitchPreference(false);
        }
        mUpdating = false;
    }

    private void updateSwitchPreference(boolean enabled) {
        String bluetoothName = BluetoothAdapter.getDefaultAdapter().getName();
        getPreference().setSummary(enabled ? getContext()
                .getString(R.string.bluetooth_state_switch_summary, bluetoothName) : null);
        getPreference().setChecked(enabled);
    }

    private void enableSwitchPreference(ColoredSwitchPreference preference, boolean enabled) {
        preference.setEnabled(enabled && getAvailabilityStatus() == AVAILABLE);
    }
}