Files
LBJ_Console/lib/services/ble_service.dart

376 lines
11 KiB
Dart

import 'dart:async';
import 'dart:convert';
import 'dart:math';
import 'package:flutter_blue_plus/flutter_blue_plus.dart';
import 'package:lbjconsole/models/train_record.dart';
import 'package:lbjconsole/services/database_service.dart';
class BLEService {
static final BLEService _instance = BLEService._internal();
factory BLEService() => _instance;
BLEService._internal();
static const String TAG = "LBJ_BT_FLUTTER";
static final Guid serviceUuid = Guid("0000ffe0-0000-1000-8000-00805f9b34fb");
static final Guid charUuid = Guid("0000ffe1-0000-1000-8000-00805f9b34fb");
BluetoothDevice? _connectedDevice;
BluetoothCharacteristic? _characteristic;
StreamSubscription<List<int>>? _valueSubscription;
StreamSubscription<BluetoothConnectionState>? _connectionStateSubscription;
StreamSubscription<List<ScanResult>>? _scanResultsSubscription;
final StreamController<String> _statusController =
StreamController<String>.broadcast();
final StreamController<TrainRecord> _dataController =
StreamController<TrainRecord>.broadcast();
final StreamController<bool> _connectionController =
StreamController<bool>.broadcast();
final StreamController<DateTime?> _lastReceivedTimeController =
StreamController<DateTime?>.broadcast();
Stream<String> get statusStream => _statusController.stream;
Stream<TrainRecord> get dataStream => _dataController.stream;
Stream<bool> get connectionStream => _connectionController.stream;
Stream<DateTime?> get lastReceivedTimeStream =>
_lastReceivedTimeController.stream;
String _deviceStatus = "未连接";
String? _lastKnownDeviceAddress;
String _targetDeviceName = "LBJReceiver";
DateTime? _lastReceivedTime;
bool _isConnecting = false;
bool _isManualDisconnect = false;
bool _isAutoConnectBlocked = false;
Timer? _heartbeatTimer;
final StringBuffer _dataBuffer = StringBuffer();
void initialize() {
_loadSettings();
FlutterBluePlus.adapterState.listen((state) {
if (state == BluetoothAdapterState.on) {
ensureConnection();
} else {
_updateConnectionState(false, "蓝牙已关闭");
stopScan();
}
});
_startHeartbeat();
}
void _startHeartbeat() {
_heartbeatTimer?.cancel();
_heartbeatTimer = Timer.periodic(const Duration(seconds: 7), (timer) {
ensureConnection();
});
}
Future<void> _loadSettings() async {
try {
final settings = await DatabaseService.instance.getAllSettings();
if (settings != null) {
_targetDeviceName = settings['deviceName'] ?? 'LBJReceiver';
}
} catch (e) {}
}
void ensureConnection() {
if (isConnected || _isConnecting) {
return;
}
_tryReconnectDirectly();
}
Future<void> _tryReconnectDirectly() async {
if (_lastKnownDeviceAddress == null) {
startScan();
return;
}
_isConnecting = true;
_statusController.add("正在重连...");
try {
final connected = await FlutterBluePlus.connectedSystemDevices;
final matchingDevices =
connected.where((d) => d.remoteId.str == _lastKnownDeviceAddress);
BluetoothDevice? target =
matchingDevices.isNotEmpty ? matchingDevices.first : null;
if (target != null) {
await connect(target);
} else {
startScan();
_isConnecting = false;
}
} catch (e) {
startScan();
_isConnecting = false;
}
}
Future<void> startScan({
String? targetName,
Duration? timeout,
Function(List<BluetoothDevice>)? onScanResults,
}) async {
if (FlutterBluePlus.isScanningNow) {
return;
}
_targetDeviceName = targetName ?? _targetDeviceName;
_statusController.add("正在扫描...");
_scanResultsSubscription?.cancel();
_scanResultsSubscription = FlutterBluePlus.scanResults.listen((results) {
final allFoundDevices = results.map((r) => r.device).toList();
final filteredDevices = allFoundDevices.where((device) {
if (_targetDeviceName.isEmpty) return true;
return device.platformName.toLowerCase() ==
_targetDeviceName.toLowerCase();
}).toList();
onScanResults?.call(filteredDevices);
if (isConnected ||
_isConnecting ||
_isManualDisconnect ||
_isAutoConnectBlocked) return;
for (var device in allFoundDevices) {
if (_shouldAutoConnectTo(device)) {
stopScan();
connect(device);
break;
}
}
});
try {
await FlutterBluePlus.startScan(timeout: timeout);
} catch (e) {
_statusController.add("扫描失败");
}
}
bool _shouldAutoConnectTo(BluetoothDevice device) {
final deviceName = device.platformName;
final deviceAddress = device.remoteId.str;
if (_targetDeviceName.isNotEmpty &&
deviceName.toLowerCase() == _targetDeviceName.toLowerCase())
return true;
if (_lastKnownDeviceAddress != null &&
_lastKnownDeviceAddress == deviceAddress) return true;
return false;
}
Future<void> stopScan() async {
await FlutterBluePlus.stopScan();
_scanResultsSubscription?.cancel();
}
Future<void> connect(BluetoothDevice device) async {
if (isConnected) return;
_isConnecting = true;
_isManualDisconnect = false;
_statusController.add("正在连接: ${device.platformName}");
try {
_connectionStateSubscription?.cancel();
_connectionStateSubscription = device.connectionState.listen((state) {
if (state == BluetoothConnectionState.disconnected) {
_onDisconnected();
}
});
await device.connect(timeout: const Duration(seconds: 15));
await _onConnected(device);
} catch (e) {
_onDisconnected();
}
}
Future<void> _onConnected(BluetoothDevice device) async {
_connectedDevice = device;
_lastKnownDeviceAddress = device.remoteId.str;
await _discoverServicesAndSetupNotifications(device);
}
void _onDisconnected() {
final wasConnected = isConnected;
_updateConnectionState(false, "连接已断开");
_connectionStateSubscription?.cancel();
if (wasConnected && !_isManualDisconnect) {
ensureConnection();
}
_isConnecting = false;
}
Future<void> _discoverServicesAndSetupNotifications(
BluetoothDevice device) async {
try {
final services = await device.discoverServices();
for (var service in services) {
if (service.uuid == serviceUuid) {
for (var char in service.characteristics) {
if (char.uuid == charUuid) {
_characteristic = char;
await device.requestMtu(512);
await char.setNotifyValue(true);
_valueSubscription = char.lastValueStream.listen(_onDataReceived);
_updateConnectionState(true, "已连接");
_isConnecting = false;
return;
}
}
}
}
await device.disconnect();
} catch (e) {
await device.disconnect();
}
}
Future<void> connectManually(BluetoothDevice device) async {
_isManualDisconnect = false;
_isAutoConnectBlocked = false;
stopScan();
await connect(device);
}
Future<void> disconnect() async {
_isManualDisconnect = true;
stopScan();
await _connectionStateSubscription?.cancel();
await _valueSubscription?.cancel();
if (_connectedDevice != null) {
await _connectedDevice!.disconnect();
}
_onDisconnected();
}
void _onDataReceived(List<int> value) {
if (value.isEmpty) return;
try {
final data = utf8.decode(value);
_dataBuffer.write(data);
_processDataBuffer();
} catch (e) {}
}
void _processDataBuffer() {
String bufferContent = _dataBuffer.toString();
if (bufferContent.isEmpty) return;
int firstBrace = bufferContent.indexOf('{');
if (firstBrace == -1) {
_dataBuffer.clear();
return;
}
bufferContent = bufferContent.substring(firstBrace);
int braceCount = 0;
int lastValidJsonEnd = -1;
for (int i = 0; i < bufferContent.length; i++) {
if (bufferContent[i] == '{') {
braceCount++;
} else if (bufferContent[i] == '}') {
braceCount--;
}
if (braceCount == 0 && i > 0) {
lastValidJsonEnd = i;
String jsonToParse = bufferContent.substring(0, lastValidJsonEnd + 1);
_parseAndNotify(jsonToParse);
bufferContent = bufferContent.substring(lastValidJsonEnd + 1);
i = -1;
firstBrace = bufferContent.indexOf('{');
if (firstBrace != -1) {
bufferContent = bufferContent.substring(firstBrace);
} else {
break;
}
}
}
_dataBuffer.clear();
if (braceCount > 0) {
_dataBuffer.write(bufferContent);
}
}
void _parseAndNotify(String jsonData) {
try {
final decodedJson = jsonDecode(jsonData);
if (decodedJson is Map<String, dynamic>) {
final now = DateTime.now();
final recordData = Map<String, dynamic>.from(decodedJson);
recordData['uniqueId'] =
'${now.millisecondsSinceEpoch}_${Random().nextInt(9999)}';
recordData['receivedTimestamp'] = now.millisecondsSinceEpoch;
if (!recordData.containsKey('timestamp')) {
recordData['timestamp'] = now.millisecondsSinceEpoch;
}
_lastReceivedTime = now;
_lastReceivedTimeController.add(_lastReceivedTime);
final trainRecord = TrainRecord.fromJson(recordData);
_dataController.add(trainRecord);
DatabaseService.instance.insertRecord(trainRecord);
}
} catch (e) {
print("$TAG: JSON Decode Error: $e, Data: $jsonData");
}
}
void _updateConnectionState(bool connected, String status) {
if (connected) {
_deviceStatus = "已连接";
} else {
_deviceStatus = status;
_connectedDevice = null;
_characteristic = null;
_lastReceivedTime = null;
_lastReceivedTimeController.add(null);
}
_statusController.add(_deviceStatus);
_connectionController.add(connected);
}
void onAppResume() {
ensureConnection();
}
void setAutoConnectBlocked(bool blocked) {
_isAutoConnectBlocked = blocked;
}
bool get isConnected => _connectedDevice != null;
String get deviceStatus => _deviceStatus;
String? get deviceAddress => _connectedDevice?.remoteId.str;
bool get isScanning => FlutterBluePlus.isScanningNow;
BluetoothDevice? get connectedDevice => _connectedDevice;
bool get isManualDisconnect => _isManualDisconnect;
void dispose() {
_heartbeatTimer?.cancel();
disconnect();
_statusController.close();
_dataController.close();
_connectionController.close();
_lastReceivedTimeController.close();
}
}