chore: Initial commit

3 files changed, 269 insertions, 0 deletions

diff --git a/app/src/main/java/com/arslaancodes/zwznfreefit/BleManager.kt b/app/src/main/java/com/arslaancodes/zwznfreefit/BleManager.kt
new file mode 100644
index 0000000..c138ead
--- /dev/null
+++ b/app/src/main/java/com/arslaancodes/zwznfreefit/BleManager.kt
@@ -0,0 +1,121 @@
+package com.arslaancodes.zwznfreefit
+
+import android.bluetooth.*
+import android.bluetooth.le.*
+import android.content.Context
+import android.os.ParcelUuid
+import java.util.UUID
+
+val SERVICE_UUID = UUID.fromString("6E40FC00-B5A3-F393-E0A9-E50E24DCCA9E")
+val WRITE_UUID   = UUID.fromString("6E40FC20-B5A3-F393-E0A9-E50E24DCCA9E")
+val NOTIFY_UUID  = UUID.fromString("6E40FC21-B5A3-F393-E0A9-E50E24DCCA9E")
+
+class BleManager(private val context: Context) {
+	companion object {
+		lateinit var instance: BleManager
+	}
+
+	init {
+		instance = this
+	}
+
+	private val adapter = BluetoothAdapter.getDefaultAdapter()
+	private var gatt: BluetoothGatt? = null
+	private var onNotify: ((ByteArray) -> Unit)? = null
+
+	fun scan(onFound: (BluetoothDevice) -> Unit) {
+		val scanner = adapter.bluetoothLeScanner
+		android.util.Log.d("BLE", "Starting scan, scanner=$scanner")
+		if (scanner == null) {
+			android.util.Log.e("BLE", "Scanner is null! Bluetooth off?")
+			return
+		}
+		val settings = ScanSettings.Builder().build()
+		scanner.startScan(null, settings, object : ScanCallback() {
+			override fun onScanResult(callbackType: Int, result: ScanResult) {
+				android.util.Log.d("BLE", "Found: ${result.device.name} ${result.device.address}")
+				onFound(result.device)
+			}
+			override fun onScanFailed(errorCode: Int) {
+				android.util.Log.e("BLE", "Scan failed: $errorCode")
+			}
+		})
+	}
+
+	fun connect(device: BluetoothDevice, onConnected: (BluetoothGatt) -> Unit) {
+		gatt = device.connectGatt(context, false, object : BluetoothGattCallback() {
+			override fun onConnectionStateChange(g: BluetoothGatt, status: Int, newState: Int) {
+				if (newState == BluetoothProfile.STATE_CONNECTED) {
+					g.discoverServices()
+				}
+			}
+			override fun onServicesDiscovered(g: BluetoothGatt, status: Int) {
+				val notifyChar = g.getService(SERVICE_UUID)?.getCharacteristic(NOTIFY_UUID)
+				if (notifyChar != null) {
+					g.setCharacteristicNotification(notifyChar, true)
+					val descriptor = notifyChar.getDescriptor(
+						UUID.fromString("00002902-0000-1000-8000-00805f9b34fb")
+					)
+					descriptor?.value = BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE
+					g.writeDescriptor(descriptor)
+				}
+				onConnected(g)
+			}
+			override fun onCharacteristicChanged(g: BluetoothGatt, characteristic: BluetoothGattCharacteristic) {
+				if (characteristic.uuid == NOTIFY_UUID) {
+					onNotify?.invoke(characteristic.value)
+				}
+			}
+		})
+	}
+
+	fun write(data: ByteArray) {
+		val char = gatt?.getService(SERVICE_UUID)?.getCharacteristic(WRITE_UUID)
+		char?.value = data
+		gatt?.writeCharacteristic(char)
+	}
+
+	fun syncTime() {
+		val now = System.currentTimeMillis() / 1000
+		val tzOffset = java.util.TimeZone.getDefault().getOffset(System.currentTimeMillis()) / 1000
+
+		val packet = ByteArray(12)
+		packet[0] = 0x01
+		packet[1] = (now shr 24).toByte()
+		packet[2] = (now shr 16).toByte()
+		packet[3] = (now shr 8).toByte()
+		packet[4] = now.toByte()
+		packet[5] = (tzOffset shr 24).toByte()
+		packet[6] = (tzOffset shr 16).toByte()
+		packet[7] = (tzOffset shr 8).toByte()
+		packet[8] = tzOffset.toByte()
+		packet[9] = 0x00
+		packet[10] = 0x00 // language code, 0 = english
+		packet[11] = 0x00
+
+		write(packet)
+	}
+
+	fun switchFindBand(flag: Int) {
+		// find/vibrate band 
+		// these functions are usually named after their freefit/ferefit counterparts
+		val packet = ByteArray(2)
+		packet[0] = 0x51 // command
+		packet[1] = flag.toByte() // 0x01 = start, 0x00 = stop
+		write(packet)
+	}
+
+	fun configRealTimeMeasure(type: Int, start: Boolean, onResult: (ByteArray) -> Unit) {
+		// measure heart rate/other stuff
+		// confirmed working types so far is just 0x00 for heart rate, will RE more later
+		// yet again, function named after freefit counterparts from RE'd protocol/decompiled APKs
+		// all code in this file is intellectual property of Arslaan Pathan, no pieces of decompiled freefit code have been used anywhere in the app
+		// freefit decompilation was merely used as a reference for reverse-engineering the protocol
+		onNotify = onResult
+		val packet = ByteArray(3)
+		packet[0] = 0x60.toByte()
+		packet[1] = type.toByte()
+		packet[2] = if (start) 0x01.toByte() else 0x00.toByte()
+		write(packet)
+	}
+}
diff --git a/app/src/main/java/com/arslaancodes/zwznfreefit/DeviceActivity.kt b/app/src/main/java/com/arslaancodes/zwznfreefit/DeviceActivity.kt
new file mode 100644
index 0000000..38862bd
--- /dev/null
+++ b/app/src/main/java/com/arslaancodes/zwznfreefit/DeviceActivity.kt
@@ -0,0 +1,73 @@
+package com.arslaancodes.zwznfreefit
+
+import android.bluetooth.BluetoothAdapter
+import android.os.Bundle
+import android.widget.TextView
+import android.widget.Button
+import androidx.appcompat.app.AppCompatActivity
+
+class DeviceActivity : AppCompatActivity() {
+	private lateinit var statusText: TextView
+	private val handler = android.os.Handler(android.os.Looper.getMainLooper())
+	private val syncRunnable = object : Runnable {
+		override fun run() {
+			BleManager.instance.syncTime()
+			handler.postDelayed(this, 5 * 60 * 1000)
+		}
+	}
+
+	override fun onResume() {
+		super.onResume()
+		handler.post(syncRunnable)
+	}
+
+	override fun onPause() {
+		super.onPause()
+		handler.removeCallbacks(syncRunnable)
+	}
+
+	override fun onCreate(savedInstanceState: Bundle?) {
+		super.onCreate(savedInstanceState)
+		setContentView(R.layout.activity_device)
+		window.decorView.systemUiVisibility = (
+			android.view.View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
+			or android.view.View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY
+		)
+
+		val address = intent.getStringExtra("device_address")
+		val device = BluetoothAdapter.getDefaultAdapter().getRemoteDevice(address)
+
+		statusText = findViewById(R.id.deviceStatusText)
+		statusText.text = "Connected to: ${device.name ?: device.address}"
+		BleManager.instance.syncTime();
+		findViewById<Button>(R.id.syncTimeButton).setOnClickListener {
+			BleManager.instance.syncTime()
+		}
+
+		findViewById<Button>(R.id.findBandButton).setOnClickListener {
+			BleManager.instance.switchFindBand(0x01)
+		}
+
+		findViewById<Button>(R.id.stopFindBandButton).setOnClickListener {
+			BleManager.instance.switchFindBand(0x00)
+		}
+
+		findViewById<Button>(R.id.configRealTimeMeasureHeartRateButton).setOnClickListener {
+			BleManager.instance.configRealTimeMeasure(0x00, true, { data ->
+				runOnUiThread {
+					if (data[0] == 0x94.toByte()) {
+						val heartRate = data[1].toInt() and 0xFF
+						statusText.text = "Got generic measurement ${heartRate}"
+					}
+					if (data[0] == 0xE1.toByte()) {
+						val rate1 = data[1].toInt() and 0xFF
+						val rate2 = data[5].toInt() and 0xFF
+						val rate3 = data[6].toInt() and 0xFF
+						val rate4 = data[7].toInt() and 0xFF
+						statusText.text = "Got aggregate rates ${rate1}, ${rate2}, ${rate3}, ${rate4}"
+					}
+				}
+			})
+		}
+	}
+}
diff --git a/app/src/main/java/com/arslaancodes/zwznfreefit/MainActivity.kt b/app/src/main/java/com/arslaancodes/zwznfreefit/MainActivity.kt
new file mode 100644
index 0000000..59bff65
--- /dev/null
+++ b/app/src/main/java/com/arslaancodes/zwznfreefit/MainActivity.kt
@@ -0,0 +1,75 @@
+package com.arslaancodes.zwznfreefit
+
+import android.Manifest
+import android.bluetooth.BluetoothDevice
+import android.content.pm.PackageManager
+import android.os.Bundle
+import android.widget.*
+import androidx.appcompat.app.AppCompatActivity
+import androidx.core.app.ActivityCompat
+import android.content.Intent
+
+class MainActivity : AppCompatActivity() {
+	private lateinit var bleManager: BleManager
+	private lateinit var statusText: TextView
+	private lateinit var scanButton: Button
+	private lateinit var deviceList: ListView
+
+	private val devices = mutableListOf<BluetoothDevice>()
+	private val deviceNames = mutableListOf<String>()
+	private lateinit var adapter: ArrayAdapter<String>
+
+	override fun onCreate(savedInstanceState: Bundle?) {
+		super.onCreate(savedInstanceState)
+		setContentView(R.layout.activity_main)
+		window.decorView.systemUiVisibility = (
+			android.view.View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
+			or android.view.View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY
+		)
+
+		bleManager = BleManager(this)
+		statusText = findViewById(R.id.statusText)
+		scanButton = findViewById(R.id.scanButton)
+		deviceList = findViewById(R.id.deviceList)
+
+		adapter = ArrayAdapter(this, android.R.layout.simple_list_item_1, deviceNames)
+		deviceList.adapter = adapter
+
+		deviceList.setOnItemClickListener { _, _, position, _ ->
+			val device = devices[position]
+			statusText.text = "Connecting to ${device.name ?: device.address}..."
+			bleManager.connect(device) {
+				runOnUiThread {
+					val intent = Intent(this, DeviceActivity::class.java)
+					intent.putExtra("device_address", device.address)
+					startActivity(intent)
+				}
+			}
+		}
+
+		scanButton.setOnClickListener {
+			if (ActivityCompat.checkSelfPermission(this, Manifest.permission.BLUETOOTH_SCAN) != PackageManager.PERMISSION_GRANTED || ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED || ActivityCompat.checkSelfPermission(this, Manifest.permission.BLUETOOTH_CONNECT) != PackageManager.PERMISSION_GRANTED) {
+				ActivityCompat.requestPermissions(this,
+					arrayOf(
+						Manifest.permission.BLUETOOTH_SCAN,
+						Manifest.permission.BLUETOOTH_CONNECT,
+						Manifest.permission.ACCESS_FINE_LOCATION
+					), 1)
+				return@setOnClickListener
+			}
+			devices.clear()
+			deviceNames.clear()
+			adapter.notifyDataSetChanged()
+			statusText.text = "Scanning..."
+			bleManager.scan { device ->
+				runOnUiThread {
+					if (devices.none { it.address == device.address }) {
+						devices.add(device)
+						deviceNames.add(device.name ?: device.address)
+						adapter.notifyDataSetChanged()
+					}
+				}
+			}
+		}
+	}
+}