BluetoothAdapter — その概要、メソッド、およびAndroidでのBluetooth管理

// BluetoothAdapterの取得（推奨）
import android.bluetooth.BluetoothAdapter
import android.bluetooth.BluetoothManager
import android.content.Context

class BluetoothHelper(context: Context) {

    private val bluetoothAdapter: BluetoothAdapter?

    init {
        // 方法1：BluetoothManager経由（API 18+）
        val manager = context.getSystemService(Context.BLUETOOTH_SERVICE)
                as BluetoothManager?
        bluetoothAdapter = manager?.adapter

        // 方法2：静的メソッド経由（API 5+）
        // val adapter = BluetoothAdapter.getDefaultAdapter()

        // nullチェック
        if (bluetoothAdapter == null) {
            // デバイスがBluetoothをサポートしていません
        }
    }

    // Bluetooth状態を確認
    fun isBluetoothEnabled(): Boolean {
        return bluetoothAdapter?.isEnabled == true
    }

    // アダプター情報を取得
    fun getAdapterInfo(): Map<String, String> {
        return mapOf(
            "name" to (bluetoothAdapter?.name ?: "N/A"),
            "address" to (bluetoothAdapter?.address ?: "N/A"),
            "state" to (bluetoothAdapter?.state?.toString() ?: "N/A"),
            "scanMode" to (bluetoothAdapter?.scanMode?.toString() ?: "N/A")
        )
    }
}

// 古い（非推奨）BLEスキャンAPI vs 新しいAPI
import android.bluetooth.BluetoothAdapter
import android.bluetooth.le.*

class BLEScanner(private val bluetoothAdapter: BluetoothAdapter?) {

    // 非推奨：startLeScan（API 18+、API 21）
    @Suppress("DEPRECATION")
    fun legacyScan() {
        bluetoothAdapter?.startLeScan { device, rssi, scanRecord ->
            print("Found (LE Scan): $device.name, RSSI: $rssi")
        }
    }

    // 新：BluetoothLeScanner（API 21+）
    fun modernScan() {
        val scanner = bluetoothAdapter?.bluetoothLeScanner
            ?: return

        // スキャン設定
        val settings = ScanSettings.Builder()
            .setScanMode(ScanSettings.SCAN_MODE_LOW_LATENCY)
            .setCallbackType(ScanSettings.CALLBACK_TYPE_ALL_MATCHES)
            .setMatchMode(ScanSettings.MATCH_MODE_AGGRESSIVE)
            .build()

        // サービスでフィルタリング（心拍数UUID）
        val filters = listOf(
            ScanFilter.Builder()
                .setServiceUuid(ParcelUuid.fromString("0000180D-0000-1000-8000-00805F9B34FB"))
                .build()
        )

        // スキャン開始
        scanner.startScan(filters, settings, object : ScanCallback() {
            override fun onScanResult(callbackType: Int, result: ScanResult) {
                val device = result.device
                val rssi = result.rssi
                print("Found (BLE Scanner): ${device.name}, RSSI: $rssi, address: ${device.address}")
            }

            override fun onScanFailed(errorCode: Int) {
                print("Scan error: $errorCode")
            }
        })
    }
}

// BLEにBluetoothManagerを使用
class BLEConnection(context: Context) {

    private val bluetoothManager: BluetoothManager =
        context.getSystemService(Context.BLUETOOTH_SERVICE) as BluetoothManager

    private val adapter: BluetoothAdapter? = bluetoothManager.adapter

    // 接続済みBLEデバイスリストを取得
    fun getConnectedDevices(): List<BluetoothDevice> {
        return bluetoothManager.getConnectedDevices(
            BluetoothProfile.GATT
        )
    }

    // 状態でデバイスをフィルタリング
    fun getDevicesByState(states: IntArray): List<BluetoothDevice> {
        return bluetoothManager.getDevicesMatchingConnectionStates(
            BluetoothProfile.GATT, states
        )
    }

    // デバイスのBLEサポートを確認
    fun isBLESupported(): Boolean {
        return adapter != null && context.packageManager
            .hasSystemFeature(PackageManager.FEATURE_BLUETOOTH_LE)
    }

    // システムダイアログ経由でBluetooth有効化を要求
    fun requestEnableBluetooth(activity: MainActivity) {
        if (adapter?.isEnabled == false) {
            val intent = Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE)
            activity.startActivityForResult(intent, REQUEST_ENABLE_BT)
        }
    }

    companion object {
        const val REQUEST_ENABLE_BT = 1001
    }
}

// Android 12+でBluetooth権限を要求
import android.Manifest
import android.content.pm.PackageManager
import android.os.Build
import androidx.core.content.ContextCompat

class PermissionHelper(context: Context) {

    fun getRequiredPermissions(): Array<String> {
        return if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.S) {
            // Android 12+：BLE-
            arrayOf(
                Manifest.permission.BLUETOOTH_SCAN,
                Manifest.permission.BLUETOOTH_CONNECT,
                Manifest.permission.BLUETOOTH_ADVERTISE
            )
        } else {
            // Android 6-11：BLE
            arrayOf(
                Manifest.permission.ACCESS_FINE_LOCATION,
                Manifest.permission.BLUETOOTH,
                Manifest.permission.BLUETOOTH_ADMIN
            )
        }
    }

    // すべての権限を確認
    fun hasPermissions(context: Context): Boolean {
        return getRequiredPermissions().all { permission ->
            ContextCompat.checkSelfPermission(context, permission)
                    == PackageManager.PERMISSION_GRANTED
        }
    }
}

// Kotlinの完全なBLEマネージャー
class BLEManager(private val context: Context) {

    private val bluetoothManager: BluetoothManager =
        context.getSystemService(Context.BLUETOOTH_SERVICE) as BluetoothManager
    private val adapter: BluetoothAdapter? = bluetoothManager.adapter
    private var scanner: BluetoothLeScanner? = adapter?.bluetoothLeScanner
    private var gatt: BluetoothGatt? = null

    // 1. サービス検出
    fun canScan(): Boolean {
        return adapter?.isEnabled == true
                && scanner != null
                && PermissionHelper(context).hasPermissions(context)
    }

    // 2. フィルター付き
    fun startScanning(callback: (BluetoothDevice, Int) -> Unit) {
        if (!canScan()) return

        val settings = ScanSettings.Builder()
            .setScanMode(ScanSettings.SCAN_MODE_LOW_LATENCY)
            .setReportDelay(0)
            .build()

        scanner?.startScan(null, settings, object : ScanCallback() {
            override fun onScanResult(callbackType: Int, result: ScanResult) {
                callback(result.device, result.rssi)
            }
        })
    }

    // 3. スキャン停止
    fun stopScanning() {
        scanner?.stopScan(object : ScanCallback() {})
    }

    // 4. BLEデバイスに接続
    fun connectToDevice(device: BluetoothDevice) {
        if (adapter?.isEnabled != true) return

        gatt = device.connectGatt(
            context,
            false,
            object : BluetoothGattCallback() {
                override fun onConnectionStateChange(gatt: BluetoothGatt, status: Int, newState: Int) {
                    if (newState == BluetoothProfile.STATE_CONNECTED) {
                        gatt.discoverServices()
                    }
                }

                override fun onServicesDiscovered(gatt: BluetoothGatt, status: Int) {
                    // サービスが見つかりました、特性を読み取れます
                }
            },
            BluetoothDevice.TRANSPORT_LE
        )
    }

    // 5. リソースを解放
    fun disconnect() {
        gatt?.disconnect()
        gatt?.close()
        gatt = null
    }
}