import 'dart:typed_data'; import 'package:cw_ethereum/pending_ethereum_transaction.dart'; import 'package:http/http.dart'; import 'package:web3dart/web3dart.dart'; import 'package:cw_core/node.dart'; import 'package:cw_ethereum/ethereum_transaction_priority.dart'; class EthereumClient { Web3Client? _client; bool connect(Node node) { try { _client = Web3Client(node.uri.toString(), Client()); return true; } catch (e) { return false; } } Future getBalance(EthereumAddress address) async => await _client!.getBalance(address); Future getGasUnitPrice() async { final gasPrice = await _client!.getGasPrice(); return gasPrice.getInWei.toInt(); } Future> getEstimatedGasForPriorities() async { // TODO: there is no difference, find out why // [53000, 53000, 53000] final result = await Future.wait(EthereumTransactionPriority.all.map( (priority) => _client!.estimateGas( maxPriorityFeePerGas: EtherAmount.fromUnitAndValue(EtherUnit.gwei, priority.tip), maxFeePerGas: EtherAmount.fromUnitAndValue(EtherUnit.gwei, priority.tip), ), )); return result.map((e) => e.toInt()).toList(); } Future signTransaction( EthPrivateKey privateKey, String toAddress, String amount, int gas, EthereumTransactionPriority priority, ) async { final estimatedGas = await _client!.estimateGas( maxPriorityFeePerGas: EtherAmount.fromUnitAndValue(EtherUnit.gwei, priority.tip), maxFeePerGas: EtherAmount.fromUnitAndValue(EtherUnit.gwei, 100), value: EtherAmount.inWei(BigInt.parse(amount)), sender: privateKey.address, to: EthereumAddress.fromHex(toAddress), ); final price = await _client!.getGasPrice(); final transaction = Transaction( from: privateKey.address, to: EthereumAddress.fromHex(toAddress), maxGas: gas, gasPrice: price, value: EtherAmount.inWei(BigInt.parse(amount)), ); final signedTransaction = await _client!.signTransaction(privateKey, transaction); return PendingEthereumTransaction( signedTransaction: signedTransaction, amount: amount, fee: estimatedGas * price.getInWei, sendTransaction: () => sendTransaction(signedTransaction), ); } Future sendTransaction(Uint8List signedTransaction) async => await _client!.sendRawTransaction(signedTransaction); Future getTransactionDetails(String transactionHash) async { // Wait for the transaction receipt to become available TransactionReceipt? receipt; while (receipt == null) { print("&&&&&&&&&&&&&&&&&&&&&&&&&&&&&"); receipt = await _client!.getTransactionReceipt(transactionHash); await Future.delayed(Duration(seconds: 1)); } // Print the receipt information print('Transaction Hash: ${receipt.transactionHash}'); print('Block Hash: ${receipt.blockHash}'); print('Block Number: ${receipt.blockNumber}'); print('Gas Used: ${receipt.gasUsed}'); /* Transaction Hash: [112, 244, 4, 238, 89, 199, 171, 191, 210, 236, 110, 42, 185, 202, 220, 21, 27, 132, 123, 221, 137, 90, 77, 13, 23, 43, 12, 230, 93, 63, 221, 116] I/flutter ( 4474): Block Hash: [149, 44, 250, 119, 111, 104, 82, 98, 17, 89, 30, 190, 25, 44, 218, 118, 127, 189, 241, 35, 213, 106, 25, 95, 195, 37, 55, 131, 185, 180, 246, 200] I/flutter ( 4474): Block Number: 17120242 I/flutter ( 4474): Gas Used: 21000 */ // Wait for the transaction receipt to become available TransactionInformation? transactionInformation; while (transactionInformation == null) { print("********************************"); transactionInformation = await _client!.getTransactionByHash(transactionHash); await Future.delayed(Duration(seconds: 1)); } // Print the receipt information print('Transaction Hash: ${transactionInformation.hash}'); print('Block Hash: ${transactionInformation.blockHash}'); print('Block Number: ${transactionInformation.blockNumber}'); print('Gas Used: ${transactionInformation.gas}'); /* Transaction Hash: 0x70f404ee59c7abbfd2ec6e2ab9cadc151b847bdd895a4d0d172b0ce65d3fdd74 I/flutter ( 4474): Block Hash: 0x952cfa776f68526211591ebe192cda767fbdf123d56a195fc3253783b9b4f6c8 I/flutter ( 4474): Block Number: 17120242 I/flutter ( 4474): Gas Used: 53000 */ } // Future> fetchTransactions(String address) async { // get(Uri.https( // "https://api.etherscan.io", // "api/", // { // "module": "account", // "action": "txlist", // "address": address, // "apikey": secrets., // }, // )); // } }