import 'dart:async'; import 'dart:convert'; import 'dart:io'; import 'dart:typed_data'; import 'package:bitcoin_flutter/bitcoin_flutter.dart'; import 'package:cw_bitcoin/bitcoin_amount_format.dart'; import 'package:cw_bitcoin/script_hash.dart'; import 'package:flutter/foundation.dart'; import 'package:rxdart/rxdart.dart'; import 'package:collection/collection.dart'; String jsonrpcparams(List<Object> params) { final _params = params?.map((val) => '"${val.toString()}"')?.join(','); return '[$_params]'; } String jsonrpc( {required String method, required List<Object> params, required int id, double version = 2.0}) => '{"jsonrpc": "$version", "method": "$method", "id": "$id", "params": ${json.encode(params)}}\n'; class SocketTask { SocketTask({ required this.isSubscription, this.completer, this.subject}); final Completer<dynamic>? completer; final BehaviorSubject<dynamic>? subject; final bool isSubscription; } class ElectrumClient { ElectrumClient() : _id = 0, _isConnected = false, _tasks = {}, unterminatedString = ''; static const connectionTimeout = Duration(seconds: 5); static const aliveTimerDuration = Duration(seconds: 4); bool get isConnected => _isConnected; Socket? socket; void Function(bool)? onConnectionStatusChange; int _id; final Map<String, SocketTask> _tasks; bool _isConnected; Timer? _aliveTimer; String unterminatedString; Future<void> connectToUri(Uri uri) async => await connect(host: uri.host, port: uri.port); Future<void> connect({required String host, required int port}) async { try { await socket?.close(); } catch (_) {} socket = await SecureSocket.connect(host, port, timeout: connectionTimeout, onBadCertificate: (_) => true); _setIsConnected(true); socket!.listen((Uint8List event) { try { final msg = utf8.decode(event.toList()); final messagesList = msg.split("\n"); for (var message in messagesList) { if (message.isEmpty) { continue; } _parseResponse(message); } } catch (e) { print(e.toString()); } }, onError: (Object error) { print(error.toString()); unterminatedString = ''; _setIsConnected(false); }, onDone: () { unterminatedString = ''; _setIsConnected(false); }); keepAlive(); } void _parseResponse(String message) { try { final response = json.decode(message) as Map<String, dynamic>; _handleResponse(response); } on FormatException catch (e) { final msg = e.message.toLowerCase(); if (e.source is String) { unterminatedString += e.source as String; } if (msg.contains("not a subtype of type")) { unterminatedString += e.source as String; return; } if (isJSONStringCorrect(unterminatedString)) { final response = json.decode(unterminatedString) as Map<String, dynamic>; _handleResponse(response); unterminatedString = ''; } } on TypeError catch (e) { if (!e.toString().contains('Map<String, Object>') && !e.toString().contains('Map<String, dynamic>')) { return; } unterminatedString += message; if (isJSONStringCorrect(unterminatedString)) { final response = json.decode(unterminatedString) as Map<String, dynamic>; _handleResponse(response); // unterminatedString = null; unterminatedString = ''; } } catch (e) { print(e.toString()); } } void keepAlive() { _aliveTimer?.cancel(); _aliveTimer = Timer.periodic(aliveTimerDuration, (_) async => ping()); } Future<void> ping() async { try { await callWithTimeout(method: 'server.ping'); _setIsConnected(true); } on RequestFailedTimeoutException catch (_) { _setIsConnected(false); } } Future<List<String>> version() => call(method: 'server.version').then((dynamic result) { if (result is List) { return result.map((dynamic val) => val.toString()).toList(); } return []; }); Future<Map<String, dynamic>> getBalance(String scriptHash) => call(method: 'blockchain.scripthash.get_balance', params: [scriptHash]) .then((dynamic result) { if (result is Map<String, dynamic>) { return result; } return <String, dynamic>{}; }); Future<List<Map<String, dynamic>>> getHistory(String scriptHash) => call(method: 'blockchain.scripthash.get_history', params: [scriptHash]) .then((dynamic result) { if (result is List) { return result.map((dynamic val) { if (val is Map<String, dynamic>) { return val; } return <String, dynamic>{}; }).toList(); } return []; }); Future<List<Map<String, dynamic>>> getListUnspentWithAddress( String address, NetworkType networkType) => call( method: 'blockchain.scripthash.listunspent', params: [scriptHash(address, networkType: networkType)]) .then((dynamic result) { if (result is List) { return result.map((dynamic val) { if (val is Map<String, dynamic>) { val['address'] = address; return val; } return <String, dynamic>{}; }).toList(); } return []; }); Future<List<Map<String, dynamic>>> getListUnspent(String scriptHash) => call(method: 'blockchain.scripthash.listunspent', params: [scriptHash]) .then((dynamic result) { if (result is List) { return result.map((dynamic val) { if (val is Map<String, dynamic>) { return val; } return <String, dynamic>{}; }).toList(); } return []; }); Future<List<Map<String, dynamic>>> getMempool(String scriptHash) => call(method: 'blockchain.scripthash.get_mempool', params: [scriptHash]) .then((dynamic result) { if (result is List) { return result.map((dynamic val) { if (val is Map<String, dynamic>) { return val; } return <String, dynamic>{}; }).toList(); } return []; }); Future<Map<String, dynamic>> getTransactionRaw( {required String hash}) async => callWithTimeout(method: 'blockchain.transaction.get', params: [hash, true], timeout: 10000) .then((dynamic result) { if (result is Map<String, dynamic>) { return result; } return <String, dynamic>{}; }); Future<String> getTransactionHex( {required String hash}) async => callWithTimeout(method: 'blockchain.transaction.get', params: [hash, false], timeout: 10000) .then((dynamic result) { if (result is String) { return result; } return ''; }); Future<String> broadcastTransaction( {required String transactionRaw}) async => call(method: 'blockchain.transaction.broadcast', params: [transactionRaw]) .then((dynamic result) { if (result is String) { return result; } return ''; }); Future<Map<String, dynamic>> getMerkle( {required String hash, required int height}) async => await call( method: 'blockchain.transaction.get_merkle', params: [hash, height]) as Map<String, dynamic>; Future<Map<String, dynamic>> getHeader({required int height}) async => await call(method: 'blockchain.block.get_header', params: [height]) as Map<String, dynamic>; Future<double> estimatefee({required int p}) => call(method: 'blockchain.estimatefee', params: [p]) .then((dynamic result) { if (result is double) { return result; } if (result is String) { return double.parse(result); } return 0; }); Future<List<List<int>>> feeHistogram() => call(method: 'mempool.get_fee_histogram').then((dynamic result) { if (result is List) { // return result.map((dynamic e) { // if (e is List) { // return e.map((dynamic ee) => ee is int ? ee : null).toList(); // } // return null; // }).toList(); final histogram = <List<int>>[]; for (final e in result) { if (e is List) { final eee = <int>[]; for (final ee in e) { if (ee is int) { eee.add(ee); } } histogram.add(eee); } } return histogram; } return []; }); Future<List<int>> feeRates() async { try { final topDoubleString = await estimatefee(p: 1); final middleDoubleString = await estimatefee(p: 5); final bottomDoubleString = await estimatefee(p: 100); final top = (stringDoubleToBitcoinAmount(topDoubleString.toString()) / 1000) .round(); final middle = (stringDoubleToBitcoinAmount(middleDoubleString.toString()) / 1000) .round(); final bottom = (stringDoubleToBitcoinAmount(bottomDoubleString.toString()) / 1000) .round(); return [bottom, middle, top]; } catch (_) { return []; } } BehaviorSubject<Object>? scripthashUpdate(String scripthash) { _id += 1; return subscribe<Object>( id: 'blockchain.scripthash.subscribe:$scripthash', method: 'blockchain.scripthash.subscribe', params: [scripthash]); } BehaviorSubject<T>? subscribe<T>( {required String id, required String method, List<Object> params = const []}) { try { final subscription = BehaviorSubject<T>(); _regisrySubscription(id, subscription); socket!.write(jsonrpc(method: method, id: _id, params: params)); return subscription; } catch(e) { print(e.toString()); return null; } } Future<dynamic> call({required String method, List<Object> params = const []}) async { final completer = Completer<dynamic>(); _id += 1; final id = _id; _registryTask(id, completer); socket!.write(jsonrpc(method: method, id: id, params: params)); return completer.future; } Future<dynamic> callWithTimeout( {required String method, List<Object> params = const [], int timeout = 4000}) async { try { final completer = Completer<dynamic>(); _id += 1; final id = _id; _registryTask(id, completer); socket!.write(jsonrpc(method: method, id: id, params: params)); Timer(Duration(milliseconds: timeout), () { if (!completer.isCompleted) { completer.completeError(RequestFailedTimeoutException(method, id)); } }); return completer.future; } catch(e) { print(e.toString()); } } Future<void> close() async { _aliveTimer?.cancel(); await socket?.close(); onConnectionStatusChange = null; } void _registryTask(int id, Completer<dynamic> completer) => _tasks[id.toString()] = SocketTask(completer: completer, isSubscription: false); void _regisrySubscription(String id, BehaviorSubject<dynamic> subject) => _tasks[id] = SocketTask(subject: subject, isSubscription: true); void _finish(String id, Object? data) { if (_tasks[id] == null) { return; } if (!(_tasks[id]?.completer?.isCompleted ?? false)) { _tasks[id]?.completer!.complete(data); } if (!(_tasks[id]?.isSubscription ?? false)) { _tasks.remove(id); } else { _tasks[id]?.subject?.add(data); } } void _methodHandler( {required String method, required Map<String, dynamic> request}) { switch (method) { case 'blockchain.scripthash.subscribe': final params = request['params'] as List<dynamic>; final scripthash = params.first as String?; final id = 'blockchain.scripthash.subscribe:$scripthash'; _tasks[id]?.subject?.add(params.last); break; default: break; } } void _setIsConnected(bool isConnected) { if (_isConnected != isConnected) { onConnectionStatusChange?.call(isConnected); } _isConnected = isConnected; } void _handleResponse(Map<String, dynamic> response) { final method = response['method']; final id = response['id'] as String?; final result = response['result']; if (method is String) { _methodHandler(method: method, request: response); return; } if (id != null){ _finish(id, result); } } } // FIXME: move me bool isJSONStringCorrect(String source) { try { json.decode(source); return true; } catch (_) { return false; } } class RequestFailedTimeoutException implements Exception { RequestFailedTimeoutException(this.method, this.id); final String method; final int id; }