mirror of
https://github.com/cake-tech/cake_wallet.git
synced 2024-12-26 21:50:27 +00:00
639 lines
20 KiB
Dart
639 lines
20 KiB
Dart
import 'dart:async';
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import 'dart:convert';
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import 'dart:math';
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import 'dart:typed_data';
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import 'package:cw_core/unspent_coins_info.dart';
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import 'package:hive/hive.dart';
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import 'package:cw_bitcoin/electrum_wallet_addresses.dart';
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import 'package:mobx/mobx.dart';
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import 'package:rxdart/subjects.dart';
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import 'package:flutter/foundation.dart';
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import 'package:bitcoin_flutter/bitcoin_flutter.dart' as bitcoin;
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import 'package:cw_bitcoin/electrum_transaction_info.dart';
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import 'package:cw_core/pathForWallet.dart';
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import 'package:cw_bitcoin/address_to_output_script.dart';
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import 'package:cw_bitcoin/bitcoin_address_record.dart';
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import 'package:cw_bitcoin/electrum_balance.dart';
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import 'package:cw_bitcoin/bitcoin_mnemonic.dart';
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import 'package:cw_bitcoin/bitcoin_transaction_credentials.dart';
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import 'package:cw_bitcoin/electrum_transaction_history.dart';
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import 'package:cw_bitcoin/bitcoin_transaction_no_inputs_exception.dart';
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import 'package:cw_bitcoin/bitcoin_transaction_priority.dart';
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import 'package:cw_bitcoin/bitcoin_transaction_wrong_balance_exception.dart';
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import 'package:cw_bitcoin/bitcoin_unspent.dart';
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import 'package:cw_bitcoin/bitcoin_wallet_keys.dart';
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import 'package:cw_bitcoin/file.dart';
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import 'package:cw_bitcoin/pending_bitcoin_transaction.dart';
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import 'package:cw_bitcoin/script_hash.dart';
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import 'package:cw_bitcoin/utils.dart';
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import 'package:cw_core/wallet_base.dart';
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import 'package:cw_core/node.dart';
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import 'package:cw_core/sync_status.dart';
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import 'package:cw_core/transaction_priority.dart';
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import 'package:cw_core/wallet_info.dart';
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import 'package:cw_bitcoin/electrum.dart';
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import 'package:hex/hex.dart';
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import 'package:cw_core/crypto_currency.dart';
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part 'electrum_wallet.g.dart';
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class ElectrumWallet = ElectrumWalletBase with _$ElectrumWallet;
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abstract class ElectrumWalletBase extends WalletBase<ElectrumBalance,
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ElectrumTransactionHistory, ElectrumTransactionInfo> with Store {
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ElectrumWalletBase(
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{@required String password,
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@required WalletInfo walletInfo,
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@required Box<UnspentCoinsInfo> unspentCoinsInfo,
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@required List<BitcoinAddressRecord> initialAddresses,
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@required this.networkType,
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@required this.mnemonic,
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ElectrumClient electrumClient,
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ElectrumBalance initialBalance})
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: balance = ObservableMap<CryptoCurrency, ElectrumBalance>.of({
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CryptoCurrency.btc: initialBalance ??
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const ElectrumBalance(confirmed: 0, unconfirmed: 0)}),
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hd = bitcoin.HDWallet.fromSeed(mnemonicToSeedBytes(mnemonic),
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network: networkType)
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.derivePath("m/0'/0"),
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syncStatus = NotConnectedSyncStatus(),
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_password = password,
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_feeRates = <int>[],
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_isTransactionUpdating = false,
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super(walletInfo) {
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this.electrumClient = electrumClient ?? ElectrumClient();
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this.walletInfo = walletInfo;
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this.unspentCoinsInfo = unspentCoinsInfo;
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transactionHistory =
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ElectrumTransactionHistory(walletInfo: walletInfo, password: password);
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unspentCoins = [];
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_scripthashesUpdateSubject = {};
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}
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static int estimatedTransactionSize(int inputsCount, int outputsCounts) =>
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inputsCount * 146 + outputsCounts * 33 + 8;
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final bitcoin.HDWallet hd;
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final String mnemonic;
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ElectrumClient electrumClient;
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Box<UnspentCoinsInfo> unspentCoinsInfo;
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@override
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ElectrumWalletAddresses walletAddresses;
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@override
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@observable
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ObservableMap<CryptoCurrency, ElectrumBalance> balance;
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@override
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@observable
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SyncStatus syncStatus;
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List<String> get scriptHashes => walletAddresses.addresses
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.map((addr) => scriptHash(addr.address, networkType: networkType))
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.toList();
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List<String> get publicScriptHashes => walletAddresses.addresses
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.where((addr) => !addr.isHidden)
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.map((addr) => scriptHash(addr.address, networkType: networkType))
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.toList();
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String get xpub => hd.base58;
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@override
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String get seed => mnemonic;
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bitcoin.NetworkType networkType;
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@override
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BitcoinWalletKeys get keys => BitcoinWalletKeys(
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wif: hd.wif, privateKey: hd.privKey, publicKey: hd.pubKey);
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final String _password;
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List<BitcoinUnspent> unspentCoins;
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List<int> _feeRates;
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Map<String, BehaviorSubject<Object>> _scripthashesUpdateSubject;
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bool _isTransactionUpdating;
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Future<void> init() async {
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await walletAddresses.init();
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await transactionHistory.init();
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await save();
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}
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@action
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@override
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Future<void> startSync() async {
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try {
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syncStatus = StartingSyncStatus();
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await walletAddresses.discoverAddresses();
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await updateTransactions();
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_subscribeForUpdates();
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await _updateBalance();
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await updateUnspent();
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_feeRates = await electrumClient.feeRates();
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Timer.periodic(const Duration(minutes: 1),
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(timer) async => _feeRates = await electrumClient.feeRates());
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syncStatus = SyncedSyncStatus();
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} catch (e) {
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print(e.toString());
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syncStatus = FailedSyncStatus();
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}
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}
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@action
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@override
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Future<void> connectToNode({@required Node node}) async {
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try {
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syncStatus = ConnectingSyncStatus();
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await electrumClient.connectToUri(node.uri);
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electrumClient.onConnectionStatusChange = (bool isConnected) {
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if (!isConnected) {
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syncStatus = LostConnectionSyncStatus();
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}
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};
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syncStatus = ConnectedSyncStatus();
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} catch (e) {
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print(e.toString());
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syncStatus = FailedSyncStatus();
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}
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}
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@override
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Future<PendingBitcoinTransaction> createTransaction(
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Object credentials) async {
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const minAmount = 546;
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final transactionCredentials = credentials as BitcoinTransactionCredentials;
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final inputs = <BitcoinUnspent>[];
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final outputs = transactionCredentials.outputs;
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final hasMultiDestination = outputs.length > 1;
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var allInputsAmount = 0;
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if (unspentCoins.isEmpty) {
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await updateUnspent();
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}
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for (final utx in unspentCoins) {
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if (utx.isSending) {
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allInputsAmount += utx.value;
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inputs.add(utx);
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}
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}
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if (inputs.isEmpty) {
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throw BitcoinTransactionNoInputsException();
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}
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final allAmountFee = feeAmountForPriority(
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transactionCredentials.priority, inputs.length, outputs.length);
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final allAmount = allInputsAmount - allAmountFee;
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var credentialsAmount = 0;
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var amount = 0;
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var fee = 0;
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if (hasMultiDestination) {
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if (outputs.any((item) => item.sendAll
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|| item.formattedCryptoAmount <= 0)) {
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throw BitcoinTransactionWrongBalanceException(currency);
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}
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credentialsAmount = outputs.fold(0, (acc, value) =>
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acc + value.formattedCryptoAmount);
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if (allAmount - credentialsAmount < minAmount) {
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throw BitcoinTransactionWrongBalanceException(currency);
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}
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amount = credentialsAmount;
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fee = calculateEstimatedFee(transactionCredentials.priority, amount,
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outputsCount: outputs.length + 1);
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} else {
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final output = outputs.first;
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credentialsAmount = !output.sendAll
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? output.formattedCryptoAmount
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: 0;
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if (credentialsAmount > allAmount) {
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throw BitcoinTransactionWrongBalanceException(currency);
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}
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amount = output.sendAll || allAmount - credentialsAmount < minAmount
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? allAmount
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: credentialsAmount;
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fee = output.sendAll || amount == allAmount
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? allAmountFee
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: calculateEstimatedFee(transactionCredentials.priority, amount);
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}
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if (fee == 0) {
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throw BitcoinTransactionWrongBalanceException(currency);
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}
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final totalAmount = amount + fee;
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if (totalAmount > balance[currency].confirmed || totalAmount > allInputsAmount) {
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throw BitcoinTransactionWrongBalanceException(currency);
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}
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final txb = bitcoin.TransactionBuilder(network: networkType);
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final changeAddress = await walletAddresses.getChangeAddress();
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var leftAmount = totalAmount;
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var totalInputAmount = 0;
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inputs.clear();
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for (final utx in unspentCoins) {
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if (utx.isSending) {
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leftAmount = leftAmount - utx.value;
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totalInputAmount += utx.value;
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inputs.add(utx);
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if (leftAmount <= 0) {
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break;
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}
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}
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}
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if (inputs.isEmpty) {
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throw BitcoinTransactionNoInputsException();
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}
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if (amount <= 0 || totalInputAmount < totalAmount) {
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throw BitcoinTransactionWrongBalanceException(currency);
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}
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txb.setVersion(1);
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inputs.forEach((input) {
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if (input.isP2wpkh) {
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final p2wpkh = bitcoin
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.P2WPKH(
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data: generatePaymentData(
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hd: input.address.isHidden ? walletAddresses.sideHd : walletAddresses.mainHd,
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index: input.address.index),
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network: networkType)
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.data;
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txb.addInput(input.hash, input.vout, null, p2wpkh.output);
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} else {
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txb.addInput(input.hash, input.vout);
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}
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});
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outputs.forEach((item) {
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final outputAmount = hasMultiDestination
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? item.formattedCryptoAmount
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: amount;
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final outputAddress = item.isParsedAddress
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? item.extractedAddress
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: item.address;
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txb.addOutput(
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addressToOutputScript(outputAddress, networkType),
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outputAmount);
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});
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final estimatedSize =
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estimatedTransactionSize(inputs.length, outputs.length + 1);
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final feeAmount = feeRate(transactionCredentials.priority) * estimatedSize;
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final changeValue = totalInputAmount - amount - feeAmount;
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if (changeValue > minAmount) {
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txb.addOutput(changeAddress, changeValue);
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}
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for (var i = 0; i < inputs.length; i++) {
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final input = inputs[i];
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final keyPair = generateKeyPair(
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hd: input.address.isHidden ? walletAddresses.sideHd : walletAddresses.mainHd,
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index: input.address.index,
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network: networkType);
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final witnessValue = input.isP2wpkh ? input.value : null;
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txb.sign(vin: i, keyPair: keyPair, witnessValue: witnessValue);
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}
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return PendingBitcoinTransaction(txb.build(), type,
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electrumClient: electrumClient, amount: amount, fee: fee)
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..addListener((transaction) async {
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transactionHistory.addOne(transaction);
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await _updateBalance();
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});
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}
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String toJSON() => json.encode({
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'mnemonic': mnemonic,
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'account_index': walletAddresses.currentReceiveAddressIndex.toString(),
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'change_address_index': walletAddresses.currentChangeAddressIndex.toString(),
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'addresses': walletAddresses.addresses.map((addr) => addr.toJSON()).toList(),
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'balance': balance[currency]?.toJSON()
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});
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int feeRate(TransactionPriority priority) {
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try {
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if (priority is BitcoinTransactionPriority) {
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return _feeRates[priority.raw];
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}
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return 0;
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} catch(_) {
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return 0;
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}
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}
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int feeAmountForPriority(BitcoinTransactionPriority priority, int inputsCount,
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int outputsCount) =>
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feeRate(priority) * estimatedTransactionSize(inputsCount, outputsCount);
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@override
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int calculateEstimatedFee(TransactionPriority priority, int amount,
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{int outputsCount}) {
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if (priority is BitcoinTransactionPriority) {
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int inputsCount = 0;
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if (amount != null) {
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int totalValue = 0;
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for (final input in unspentCoins) {
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if (totalValue >= amount) {
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break;
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}
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if (input.isSending) {
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totalValue += input.value;
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inputsCount += 1;
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}
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}
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if (totalValue < amount) return 0;
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} else {
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for (final input in unspentCoins) {
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if (input.isSending) {
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inputsCount += 1;
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}
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}
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}
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// If send all, then we have no change value
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final _outputsCount = outputsCount ?? (amount != null ? 2 : 1);
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return feeAmountForPriority(
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priority, inputsCount, _outputsCount);
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}
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return 0;
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}
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@override
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Future<void> save() async {
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final path = await makePath();
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await write(path: path, password: _password, data: toJSON());
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await transactionHistory.save();
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}
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bitcoin.ECPair keyPairFor({@required int index}) =>
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generateKeyPair(hd: hd, index: index, network: networkType);
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@override
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Future<void> rescan({int height}) async => throw UnimplementedError();
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@override
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Future<void> close() async {
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try {
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await electrumClient?.close();
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} catch (_) {}
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}
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Future<String> makePath() async =>
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pathForWallet(name: walletInfo.name, type: walletInfo.type);
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Future<void> updateUnspent() async {
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final unspent = await Future.wait(walletAddresses
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.addresses.map((address) => electrumClient
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.getListUnspentWithAddress(address.address, networkType)
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.then((unspent) => unspent
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.map((unspent) => BitcoinUnspent.fromJSON(address, unspent)))));
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unspentCoins = unspent.expand((e) => e).toList();
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if (unspentCoinsInfo.isEmpty) {
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unspentCoins.forEach((coin) => _addCoinInfo(coin));
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return;
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}
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if (unspentCoins.isNotEmpty) {
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unspentCoins.forEach((coin) {
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final coinInfoList = unspentCoinsInfo.values.where((element) =>
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element.walletId.contains(id) && element.hash.contains(coin.hash));
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if (coinInfoList.isNotEmpty) {
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final coinInfo = coinInfoList.first;
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coin.isFrozen = coinInfo.isFrozen;
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coin.isSending = coinInfo.isSending;
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coin.note = coinInfo.note;
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} else {
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_addCoinInfo(coin);
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}
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});
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}
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await _refreshUnspentCoinsInfo();
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}
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Future<void> _addCoinInfo(BitcoinUnspent coin) async {
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final newInfo = UnspentCoinsInfo(
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walletId: id,
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hash: coin.hash,
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isFrozen: coin.isFrozen,
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isSending: coin.isSending,
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note: coin.note
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);
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await unspentCoinsInfo.add(newInfo);
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}
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Future<void> _refreshUnspentCoinsInfo() async {
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try {
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final List<dynamic> keys = <dynamic>[];
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final currentWalletUnspentCoins = unspentCoinsInfo.values
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.where((element) => element.walletId.contains(id));
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if (currentWalletUnspentCoins.isNotEmpty) {
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currentWalletUnspentCoins.forEach((element) {
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final existUnspentCoins = unspentCoins
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?.where((coin) => element.hash.contains(coin?.hash));
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if (existUnspentCoins?.isEmpty ?? true) {
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keys.add(element.key);
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}
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});
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}
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if (keys.isNotEmpty) {
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await unspentCoinsInfo.deleteAll(keys);
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}
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} catch (e) {
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print(e.toString());
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}
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}
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Future<ElectrumTransactionBundle> getTransactionExpanded(
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{@required String hash, @required int height}) async {
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final verboseTransaction = await electrumClient.getTransactionRaw(hash: hash);
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final transactionHex = verboseTransaction['hex'] as String;
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final original = bitcoin.Transaction.fromHex(transactionHex);
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final ins = <bitcoin.Transaction>[];
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final time = verboseTransaction['time'] as int;
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final confirmations = verboseTransaction['confirmations'] as int ?? 0;
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for (final vin in original.ins) {
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final id = HEX.encode(vin.hash.reversed.toList());
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final txHex = await electrumClient.getTransactionHex(hash: id);
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final tx = bitcoin.Transaction.fromHex(txHex);
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ins.add(tx);
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}
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return ElectrumTransactionBundle(
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original,
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ins: ins,
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time: time,
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confirmations: confirmations);
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}
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Future<ElectrumTransactionInfo> fetchTransactionInfo(
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{@required String hash, @required int height}) async {
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final tx = await getTransactionExpanded(hash: hash, height: height);
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final addresses = walletAddresses.addresses.map((addr) => addr.address).toSet();
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return ElectrumTransactionInfo.fromElectrumBundle(
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tx,
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walletInfo.type,
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networkType,
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addresses: addresses,
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height: height);
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}
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@override
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Future<Map<String, ElectrumTransactionInfo>> fetchTransactions() async {
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final addressHashes = <String, BitcoinAddressRecord>{};
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final normalizedHistories = <Map<String, dynamic>>[];
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walletAddresses.addresses.forEach((addressRecord) {
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if (addressRecord.isHidden) {
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return;
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}
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final sh = scriptHash(addressRecord.address, networkType: networkType);
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addressHashes[sh] = addressRecord;
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});
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final histories =
|
|
addressHashes.keys.map((scriptHash) => electrumClient
|
|
.getHistory(scriptHash)
|
|
.then((history) => {scriptHash: history}));
|
|
final historyResults = await Future.wait(histories);
|
|
historyResults.forEach((history) {
|
|
history.entries.forEach((historyItem) {
|
|
if (historyItem.value.isNotEmpty) {
|
|
final address = addressHashes[historyItem.key];
|
|
address.setAsUsed();
|
|
normalizedHistories.addAll(historyItem.value);
|
|
}
|
|
});
|
|
});
|
|
final historiesWithDetails = await Future.wait(
|
|
normalizedHistories
|
|
.map((transaction) => fetchTransactionInfo(
|
|
hash: transaction['tx_hash'] as String,
|
|
height: transaction['height'] as int)));
|
|
|
|
return historiesWithDetails.fold<Map<String, ElectrumTransactionInfo>>(
|
|
<String, ElectrumTransactionInfo>{}, (acc, tx) {
|
|
acc[tx.id] = acc[tx.id]?.updated(tx) ?? tx;
|
|
return acc;
|
|
});
|
|
}
|
|
|
|
Future<void> updateTransactions() async {
|
|
try {
|
|
if (_isTransactionUpdating) {
|
|
return;
|
|
}
|
|
|
|
_isTransactionUpdating = true;
|
|
final transactions = await fetchTransactions();
|
|
transactionHistory.addMany(transactions);
|
|
walletAddresses.updateReceiveAddresses();
|
|
await transactionHistory.save();
|
|
_isTransactionUpdating = false;
|
|
} catch (e) {
|
|
print(e);
|
|
_isTransactionUpdating = false;
|
|
}
|
|
}
|
|
|
|
void _subscribeForUpdates() {
|
|
scriptHashes.forEach((sh) async {
|
|
await _scripthashesUpdateSubject[sh]?.close();
|
|
_scripthashesUpdateSubject[sh] = electrumClient.scripthashUpdate(sh);
|
|
_scripthashesUpdateSubject[sh]?.listen((event) async {
|
|
try {
|
|
await _updateBalance();
|
|
await updateUnspent();
|
|
await updateTransactions();
|
|
} catch (e) {
|
|
print(e.toString());
|
|
}
|
|
});
|
|
});
|
|
}
|
|
|
|
Future<ElectrumBalance> _fetchBalances() async {
|
|
final addresses = walletAddresses.addresses.toList();
|
|
final balanceFutures = <Future<Map<String, dynamic>>>[];
|
|
|
|
for (var i = 0; i < addresses.length; i++) {
|
|
final addressRecord = addresses[i];
|
|
final sh = scriptHash(addressRecord.address, networkType: networkType);
|
|
final balanceFuture = electrumClient.getBalance(sh);
|
|
balanceFutures.add(balanceFuture);
|
|
}
|
|
|
|
final balances = await Future.wait(balanceFutures);
|
|
var totalConfirmed = 0;
|
|
var totalUnconfirmed = 0;
|
|
|
|
for (var i = 0; i < balances.length; i++) {
|
|
final addressRecord = addresses[i];
|
|
final balance = balances[i];
|
|
final confirmed = balance['confirmed'] as int ?? 0;
|
|
final unconfirmed = balance['unconfirmed'] as int ?? 0;
|
|
totalConfirmed += confirmed;
|
|
totalUnconfirmed += unconfirmed;
|
|
|
|
if (confirmed > 0 || unconfirmed > 0) {
|
|
addressRecord.setAsUsed();
|
|
}
|
|
}
|
|
|
|
return ElectrumBalance(confirmed: totalConfirmed, unconfirmed: totalUnconfirmed);
|
|
}
|
|
|
|
Future<void> _updateBalance() async {
|
|
balance[currency] = await _fetchBalances();
|
|
await save();
|
|
}
|
|
|
|
String getChangeAddress() {
|
|
const minCountOfHiddenAddresses = 5;
|
|
final random = Random();
|
|
var addresses = walletAddresses.addresses
|
|
.where((addr) => addr.isHidden)
|
|
.toList();
|
|
|
|
if (addresses.length < minCountOfHiddenAddresses) {
|
|
addresses = walletAddresses.addresses.toList();
|
|
}
|
|
|
|
return addresses[random.nextInt(addresses.length)].address;
|
|
}
|
|
}
|