package com.github.antweb.donkey

import android.bluetooth.*
import android.os.Bundle
import android.util.Log
import android.widget.TextView
import androidx.appcompat.app.AppCompatActivity
import com.github.antweb.donkey.file.FileTransfer
import java.lang.NullPointerException
import java.util.*

private const val TAG = "SendActivity"

class SendActivity : AppCompatActivity() {
    private val mtu = 128
    private val serviceUuid = "00422342-2342-2342-2342-234223422342"

    private val centralTxCharacteristicUuid = UUID.fromString("01422342-2342-2342-2342-234223422342")
    private val centralRxCharacteristicUuid = UUID.fromString("02422342-2342-2342-2342-234223422342")

    private var bluetoothGatt: BluetoothGatt? = null
    private var fileService: BluetoothGattService? = null

    private var mGatt: BluetoothGatt? = null
    private var fileTransferService: FileTransfer? = null

    private lateinit var tvConnection: TextView
    private lateinit var tvValue: TextView

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_send)

        tvValue = findViewById(R.id.text_value)
        tvConnection = findViewById(R.id.text_connection_status)
        tvConnection.text = "STATE_DISCONNECTED"

        val device = ScanActivity.selectedDevice
        if (device != null) {
            connect(device)
        } else {
            Log.e(TAG, "Device is NULL!")
        }
    }

    fun connect(device: BluetoothDevice) {
        val gattCallback = object : BluetoothGattCallback() {
            override fun onServicesDiscovered(gatt: BluetoothGatt?, status: Int) {
                if (gatt == null) {
                    throw NullPointerException()
                }

                for (service in gatt.services) {
                    Log.d(TAG, "Found service: ${service.uuid}")

                    if (service.uuid.toString() == serviceUuid) {
                        fileService = service
                    }
                }

                if (fileService == null) {
                    Log.e(TAG, "Could not find file transfer service")
                    return
                }

                gatt.requestMtu(mtu)
            }

            override fun onConnectionStateChange(gatt: BluetoothGatt?, status: Int, newState: Int) {
                when (newState) {
                    BluetoothGatt.STATE_CONNECTED -> {
                        runOnUiThread {
                            tvConnection.text = "STATE_CONNECTED"
                        }

                        mGatt = gatt
                        gatt?.discoverServices()
                    }
                    BluetoothGatt.STATE_DISCONNECTED -> tvConnection.text = "STATE_DISCONNECTED"
                    BluetoothGatt.STATE_CONNECTING -> tvConnection.text = "STATE_CONNECTING"
                    BluetoothGatt.STATE_DISCONNECTING -> tvConnection.text = "STATE_DISCONNECTING"
                }
            }

            override fun onCharacteristicChanged(gatt: BluetoothGatt?, characteristic: BluetoothGattCharacteristic?) {
                super.onCharacteristicChanged(gatt, characteristic)
            }

            override fun onCharacteristicRead(
                gatt: BluetoothGatt?,
                characteristic: BluetoothGattCharacteristic?,
                status: Int
            ) {
                super.onCharacteristicRead(gatt, characteristic, status)
            }

            override fun onMtuChanged(gatt: BluetoothGatt?, mtu: Int, status: Int) {
                Log.d(TAG, "MTU changed to: $mtu")

                runOnUiThread {
                    tvValue.text = "MTU: $mtu"
                }

                val tx = fileService?.getCharacteristic(centralTxCharacteristicUuid)
                val rx = fileService?.getCharacteristic(centralRxCharacteristicUuid)


                if (gatt != null && tx != null && rx != null) {

                    val notifySuccess = gatt.setCharacteristicNotification(rx, true)
                    if (!notifySuccess) {
                        Log.e(TAG, "Notify enable failed")
                    }

//                    fileTransferService = FileTransfer("/Download/SEND.txt", mtu)
//                    fileTransferService?.sendFile()
                }
            }

            override fun onCharacteristicWrite(
                gatt: BluetoothGatt?,
                characteristic: BluetoothGattCharacteristic?,
                status: Int
            ) {
//                Thread.sleep(3000)
//                fileTransferService?.sendNext()
//                return
            }
        }

        bluetoothGatt = device.connectGatt(this, true, gattCallback, BluetoothDevice.TRANSPORT_LE)
    }
}