cake_wallet/lib/bitcoin/electrum.dart
2020-09-07 18:13:39 +03:00

345 lines
9.5 KiB
Dart

import 'dart:async';
import 'dart:convert';
import 'dart:io';
import 'dart:typed_data';
import 'package:cake_wallet/bitcoin/script_hash.dart';
import 'package:flutter/foundation.dart';
import 'package:rxdart/rxdart.dart';
String jsonrpcparams(List<Object> params) {
final _params = params?.map((val) => '"${val.toString()}"')?.join(',');
return '[$_params]';
}
String jsonrpc(
{String method, List<Object> params, int id, double version = 2.0}) =>
'{"jsonrpc": "$version", "method": "$method", "id": "$id", "params": ${json.encode(params)}}\n';
class SocketTask {
SocketTask({this.completer, this.isSubscription, this.subject});
final Completer completer;
final BehaviorSubject subject;
final bool isSubscription;
}
class ElectrumClient {
ElectrumClient()
: _id = 0,
_isConnected = false,
_tasks = {};
static const connectionTimeout = Duration(seconds: 5);
bool get isConnected => _isConnected;
Socket socket;
void Function(bool) onConnectionStatusChange;
int _id;
final Map<String, SocketTask> _tasks;
bool _isConnected;
Timer _aliveTimer;
Future<void> connectToUri(String uri) async {
final _uri = Uri.parse(uri);
final host = _uri.scheme;
final port = int.parse(_uri.path);
await connect(host: host, port: port);
}
Future<void> connect({@required String host, @required int port}) async {
try {
await socket?.close();
} catch (_) {}
socket = await SecureSocket.connect(host, port, timeout: connectionTimeout);
_setIsConnected(true);
socket.listen((Uint8List event) {
try {
final jsoned =
json.decode(utf8.decode(event.toList())) as Map<String, Object>;
print(jsoned);
final method = jsoned['method'];
final id = jsoned['id'] as String;
final params = jsoned['result'];
if (method is String) {
_methodHandler(method: method, request: jsoned);
return;
}
_finish(id, params);
} catch (e) {
print(e);
}
}, onError: (Object error) {
print(error.toString());
_setIsConnected(false);
}, onDone: () => _setIsConnected(false));
keepAlive();
}
void keepAlive() {
_aliveTimer?.cancel();
// FIXME: Unnamed constant.
_aliveTimer = Timer.periodic(Duration(seconds: 2), (_) 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, Object>> getBalance(String scriptHash) =>
call(method: 'blockchain.scripthash.get_balance', params: [scriptHash])
.then((dynamic result) {
if (result is Map<String, Object>) {
return result;
}
return <String, Object>{};
});
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, Object>) {
return val;
}
return <String, Object>{};
}).toList();
}
return [];
});
Future<List<Map<String, dynamic>>> getListUnspentWithAddress(
String address) =>
call(
method: 'blockchain.scripthash.listunspent',
params: [scriptHash(address)]).then((dynamic result) {
if (result is List) {
return result.map((dynamic val) {
if (val is Map<String, Object>) {
val['address'] = address;
return val;
}
return <String, Object>{};
}).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, Object>) {
return val;
}
return <String, Object>{};
}).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, Object>) {
return val;
}
return <String, Object>{};
}).toList();
}
return [];
});
Future<Map<String, Object>> getTransactionRaw(
{@required String hash}) async =>
call(method: 'blockchain.transaction.get', params: [hash, true])
.then((dynamic result) {
if (result is Map<String, Object>) {
return result;
}
return <String, Object>{};
});
Future<Map<String, Object>> getTransactionExpanded(
{@required String hash}) async {
final originalTx = await getTransactionRaw(hash: hash);
final vins = originalTx['vin'] as List<Object>;
for (dynamic vin in vins) {
if (vin is Map<String, Object>) {
vin['tx'] = await getTransactionRaw(hash: vin['txid'] as String);
}
}
return originalTx;
}
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;
});
BehaviorSubject<Object> scripthashUpdate(String scripthash) =>
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 []}) {
final subscription = BehaviorSubject<T>();
_regisrySubscription(id, subscription);
socket.write(jsonrpc(method: method, id: _id, params: params));
return subscription;
}
Future<dynamic> call({String method, List<Object> params = const []}) {
final completer = Completer<dynamic>();
_id += 1;
final id = _id;
_regisryTask(id, completer);
socket.write(jsonrpc(method: method, id: _id, params: params));
return completer.future;
}
Future<dynamic> callWithTimeout(
{String method,
List<Object> params = const [],
int timeout = 2000}) async {
final completer = Completer<dynamic>();
_id += 1;
final id = _id;
_regisryTask(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;
}
void request({String method, List<Object> params = const []}) {
_id += 1;
socket.write(jsonrpc(method: method, id: _id, params: params));
}
void _regisryTask(int id, Completer completer) => _tasks[id.toString()] =
SocketTask(completer: completer, isSubscription: false);
void _regisrySubscription(String id, BehaviorSubject 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[id] = null;
} else {
_tasks[id].subject.add(data);
}
}
void _methodHandler(
{@required String method, @required Map<String, Object> 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;
}
}
class RequestFailedTimeoutException implements Exception {
RequestFailedTimeoutException(this.method, this.id);
final String method;
final int id;
}