/*  Copyright (C) 2020-2024 Arjan Schrijver, Damien Gaignon, Da Pa

    This file is part of Gadgetbridge.

    Gadgetbridge is free software: you can redistribute it and/or modify
    it under the terms of the GNU Affero General Public License as published
    by the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    Gadgetbridge is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Affero General Public License for more details.

    You should have received a copy of the GNU Affero General Public License
    along with this program.  If not, see <https://www.gnu.org/licenses/>. */
package nodomain.freeyourgadget.gadgetbridge.service.devices.jyou;

import android.bluetooth.BluetoothGatt;
import android.bluetooth.BluetoothGattCharacteristic;
import android.widget.Toast;

import org.slf4j.Logger;

import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.Calendar;

import nodomain.freeyourgadget.gadgetbridge.deviceevents.GBDeviceEventBatteryInfo;
import nodomain.freeyourgadget.gadgetbridge.deviceevents.GBDeviceEventVersionInfo;
import nodomain.freeyourgadget.gadgetbridge.devices.jyou.JYouConstants;
import nodomain.freeyourgadget.gadgetbridge.impl.GBDevice;
import nodomain.freeyourgadget.gadgetbridge.model.Alarm;
import nodomain.freeyourgadget.gadgetbridge.model.CallSpec;
import nodomain.freeyourgadget.gadgetbridge.model.NotificationSpec;
import nodomain.freeyourgadget.gadgetbridge.service.btle.AbstractBTLEDeviceSupport;
import nodomain.freeyourgadget.gadgetbridge.service.btle.TransactionBuilder;
import nodomain.freeyourgadget.gadgetbridge.util.AlarmUtils;
import nodomain.freeyourgadget.gadgetbridge.util.GB;
import nodomain.freeyourgadget.gadgetbridge.util.StringUtils;

public class JYouSupport extends AbstractBTLEDeviceSupport {

    private Logger logger;

    protected BluetoothGattCharacteristic ctrlCharacteristic = null;

    protected final GBDeviceEventVersionInfo versionCmd = new GBDeviceEventVersionInfo();
    protected final GBDeviceEventBatteryInfo batteryCmd = new GBDeviceEventBatteryInfo();

    public JYouSupport(Logger logger) {
        super(logger);
        this.logger = logger;
        if (logger == null) {
            throw new IllegalArgumentException("logger must not be null");
        }
        addSupportedService(JYouConstants.UUID_SERVICE_JYOU);
    }

    @Override
    protected TransactionBuilder initializeDevice(TransactionBuilder builder) {
        logger.info("Initializing");

        gbDevice.setState(GBDevice.State.INITIALIZING);
        gbDevice.sendDeviceUpdateIntent(getContext());

        BluetoothGattCharacteristic measureCharacteristic = getCharacteristic(JYouConstants.UUID_CHARACTERISTIC_MEASURE);
        ctrlCharacteristic = getCharacteristic(JYouConstants.UUID_CHARACTERISTIC_CONTROL);

        builder.setCallback(this);
        builder.notify(measureCharacteristic, true);

        syncSettings(builder);

        gbDevice.setState(GBDevice.State.INITIALIZED);
        gbDevice.sendDeviceUpdateIntent(getContext());

        logger.info("Initialization Done");

        return builder;
    }

    @Override
    public boolean onCharacteristicChanged(BluetoothGatt gatt,
                                           BluetoothGattCharacteristic characteristic) {
        return super.onCharacteristicChanged(gatt, characteristic);
    }

    protected void syncDateAndTime(TransactionBuilder builder) {
        Calendar cal = Calendar.getInstance();
        String strYear = String.valueOf(cal.get(Calendar.YEAR));
        byte year1 = (byte)Integer.parseInt(strYear.substring(0, 2));
        byte year2 = (byte)Integer.parseInt(strYear.substring(2, 4));
        byte month = (byte)cal.get(Calendar.MONTH);
        byte day = (byte)cal.get(Calendar.DAY_OF_MONTH);
        byte hour = (byte)cal.get(Calendar.HOUR_OF_DAY);
        byte minute = (byte)cal.get(Calendar.MINUTE);
        byte second = (byte)cal.get(Calendar.SECOND);
        byte weekDay = (byte)cal.get(Calendar.DAY_OF_WEEK);

        builder.write(ctrlCharacteristic, commandWithChecksum(
                JYouConstants.CMD_SET_DATE_AND_TIME,
                (year1 << 24) | (year2 << 16) | (month << 8) | day,
                (hour << 24) | (minute << 16) | (second << 8) | weekDay
        ));
    }

    protected void syncSettings(TransactionBuilder builder) {
    }

    private void showNotification(byte icon, String title, String message) {
        try {
            TransactionBuilder builder = performInitialized("ShowNotification");

            byte[] titleBytes = stringToUTF8Bytes(title, 16);
            byte[] messageBytes = stringToUTF8Bytes(message, 80);

            for (int i = 1; i <= 7; i++)
            {
                byte[] currentPacket = new byte[20];
                currentPacket[0] = JYouConstants.CMD_ACTION_SHOW_NOTIFICATION;
                currentPacket[1] = 7;
                currentPacket[2] = (byte)i;
                switch(i) {
                    case 1:
                        currentPacket[4] = icon;
                        break;
                    case 2:
                        if (titleBytes != null) {
                            System.arraycopy(titleBytes, 0, currentPacket, 3, 6);
                            System.arraycopy(titleBytes, 6, currentPacket, 10, 10);
                        }
                        break;
                    default:
                        if (messageBytes != null) {
                            System.arraycopy(messageBytes, 16 * (i - 3), currentPacket, 3, 6);
                            System.arraycopy(messageBytes, 6 + 16 * (i - 3), currentPacket, 10, 10);
                        }
                        break;
                }
                builder.write(ctrlCharacteristic, currentPacket);
            }
            performConnected(builder.getTransaction());
        } catch (IOException e) {
            logger.warn(e.getMessage());
        }
    }

    @Override
    public boolean useAutoConnect() {
        return true;
    }

    @Override
    public void onNotification(NotificationSpec notificationSpec) {
        String notificationTitle = StringUtils.getFirstOf(notificationSpec.sender, notificationSpec.title);
        byte icon;
        switch (notificationSpec.type) {
            case GENERIC_SMS:
                icon = JYouConstants.ICON_SMS;
                break;
            case FACEBOOK:
            case FACEBOOK_MESSENGER:
                icon = JYouConstants.ICON_FACEBOOK;
                break;
            case TWITTER:
                icon = JYouConstants.ICON_TWITTER;
                break;
            case WHATSAPP:
                icon = JYouConstants.ICON_WHATSAPP;
                break;
            default:
                icon = JYouConstants.ICON_LINE;
                break;
        }
        showNotification(icon, notificationTitle, notificationSpec.body);
    }

    @Override
    public void onSetAlarms(ArrayList<? extends Alarm> alarms) {
        try {
            TransactionBuilder builder = performInitialized("SetAlarms");

            for (int i = 0; i < alarms.size(); i++)
            {
                byte cmd;
                switch (i) {
                    case 0:
                        cmd = JYouConstants.CMD_SET_ALARM_1;
                        break;
                    case 1:
                        cmd = JYouConstants.CMD_SET_ALARM_2;
                        break;
                    case 2:
                        cmd = JYouConstants.CMD_SET_ALARM_3;
                        break;
                    default:
                        return;
                }
                Calendar cal = AlarmUtils.toCalendar(alarms.get(i));
                builder.write(ctrlCharacteristic, commandWithChecksum(
                        cmd,
                        alarms.get(i).getEnabled() ? cal.get(Calendar.HOUR_OF_DAY) : -1,
                        alarms.get(i).getEnabled() ? cal.get(Calendar.MINUTE) : -1
                ));
            }
            performConnected(builder.getTransaction());
            GB.toast(getContext(), "Alarm settings applied - do note that the current device does not support day specification", Toast.LENGTH_LONG, GB.INFO);
        } catch(IOException e) {
            logger.warn(e.getMessage());
        }
    }

    @Override
    public void onSetTime() {
        try {
            TransactionBuilder builder = performInitialized("SetTime");
            syncDateAndTime(builder);
            performConnected(builder.getTransaction());
        } catch(IOException e) {
            logger.warn(e.getMessage());
        }
    }

    @Override
    public void onSetCallState(CallSpec callSpec) {
        if(callSpec.command == CallSpec.CALL_INCOMING) {
            showNotification(JYouConstants.ICON_CALL, callSpec.name, callSpec.number);
        }
    }

    @Override
    public void onEnableRealtimeSteps(boolean enable) {
        onEnableRealtimeHeartRateMeasurement(enable);
    }

    @Override
    public void onReset(int flags) {
        try {
            TransactionBuilder builder = performInitialized("Reboot");
            builder.write(ctrlCharacteristic, commandWithChecksum(
                    JYouConstants.CMD_ACTION_REBOOT_DEVICE, 0, 0
            ));
            performConnected(builder.getTransaction());
        } catch(Exception e) {
            logger.warn(e.getMessage());
        }
    }

    @Override
    public void onHeartRateTest() {
        try {
            TransactionBuilder builder = performInitialized("HeartRateTest");
            builder.write(ctrlCharacteristic, commandWithChecksum(
                    JYouConstants.CMD_ACTION_HEARTRATE_SWITCH, 0, 1
            ));
            performConnected(builder.getTransaction());
        } catch(Exception e) {
            logger.warn(e.getMessage());
        }
    }

    @Override
    public void onEnableRealtimeHeartRateMeasurement(boolean enable) {
        try {
            TransactionBuilder builder = performInitialized("RealTimeHeartMeasurement");
            builder.write(ctrlCharacteristic, commandWithChecksum(
                    JYouConstants.CMD_SET_HEARTRATE_AUTO, 0, enable ? 1 : 0
            ));
            builder.queue(getQueue());
        } catch(Exception e) {
            logger.warn(e.getMessage());
        }
    }

    @Override
    public void onFindDevice(boolean start) {
        if (start) {
            showNotification(JYouConstants.ICON_QQ, "Gadgetbridge", "Bzzt! Bzzt!");
            GB.toast(getContext(), "As your device doesn't have sound, it will only vibrate 3 times consecutively", Toast.LENGTH_LONG, GB.INFO);
        }
    }

    protected byte[] commandWithChecksum(byte cmd, int argSlot1, int argSlot2)
    {
        ByteBuffer buf = ByteBuffer.allocate(10);
        buf.put(cmd);
        buf.putInt(argSlot1);
        buf.putInt(argSlot2);

        byte[] bytesToWrite = buf.array();

        byte checksum = 0;
        for (byte b : bytesToWrite) {
            checksum += b;
        }

        bytesToWrite[9] = checksum;

        return bytesToWrite;
    }

    private byte[] stringToUTF8Bytes(String src, int byteCount) {
        try {
            if (src == null)
                return null;

            for (int i = src.length(); i > 0; i--) {
                String sub = src.substring(0, i);
                byte[] subUTF8 = sub.getBytes("UTF-8");

                if (subUTF8.length == byteCount) {
                    return subUTF8;
                }

                if (subUTF8.length < byteCount) {
                    byte[] largerSubUTF8 = new byte[byteCount];
                    System.arraycopy(subUTF8, 0, largerSubUTF8, 0, subUTF8.length);
                    return largerSubUTF8;
                }
            }
        } catch (UnsupportedEncodingException e) {
            logger.warn(e.getMessage());
        }
        return null;
    }

    @Override
    public boolean getImplicitCallbackModify() {
        return true;
    }

    @Override
    public boolean getSendWriteRequestResponse() {
        return false;
    }
}