cake_wallet/cw_nano/lib/nano_client.dart
2023-08-02 11:47:00 -04:00

413 lines
12 KiB
Dart

import 'dart:async';
import 'dart:convert';
import 'dart:math';
import 'package:cw_core/crypto_currency.dart';
import 'package:cw_core/erc20_token.dart';
import 'package:cw_nano/nano_balance.dart';
import 'package:cw_nano/nano_transaction_model.dart';
import 'package:cw_nano/nano_util.dart';
import 'package:flutter/services.dart';
import 'package:http/http.dart' as http;
import 'package:nanodart/nanodart.dart';
import 'package:web3dart/web3dart.dart';
import 'package:web3dart/contracts/erc20.dart';
import 'package:cw_core/node.dart';
class NanoClient {
// bit of a hack since we need access to a node in a weird location:
static const String BACKUP_NODE_URI = "rpc.nano.to";
static const String DEFAULT_REPRESENTATIVE =
"nano_38713x95zyjsqzx6nm1dsom1jmm668owkeb9913ax6nfgj15az3nu8xkx579";
StreamSubscription<Transfer>? subscription;
Node? _node;
bool connect(Node node) {
try {
_node = node;
return true;
} catch (e) {
return false;
}
}
Future<NanoBalance> getBalance(String address) async {
final response = await http.post(
_node!.uri,
headers: {"Content-Type": "application/json"},
body: jsonEncode(
{
"action": "account_balance",
"account": address,
},
),
);
final data = await jsonDecode(response.body);
final String currentBalance = data["balance"] as String;
final String receivableBalance = data["receivable"] as String;
final BigInt cur = BigInt.parse(currentBalance);
final BigInt rec = BigInt.parse(receivableBalance);
return NanoBalance(currentBalance: cur, receivableBalance: rec);
}
Future<dynamic> getAccountInfo(String address) async {
try {
final response = await http.post(
_node!.uri,
headers: {"Content-Type": "application/json"},
body: jsonEncode(
{
"action": "account_info",
"representative": "true",
"account": address,
},
),
);
final data = await jsonDecode(response.body);
return data;
} catch (e) {
print("error while getting account info");
rethrow;
}
}
Future<String> requestWork(String hash) async {
return http
.post(
Uri.parse("https://rpc.nano.to"), // TODO: make a setting
headers: {'Content-type': 'application/json'},
body: json.encode(
{
"action": "work_generate",
"hash": hash,
},
),
)
.then((http.Response response) {
if (response.statusCode == 200) {
final Map<String, dynamic> decoded = json.decode(response.body) as Map<String, dynamic>;
if (decoded.containsKey("error")) {
throw Exception("Received error ${decoded["error"]}");
}
return decoded["work"] as String;
} else {
throw Exception("Received error ${response.statusCode}");
}
});
}
Future<String> send({
required String privateKey,
required String amountRaw,
required String destinationAddress,
}) async {
final Map<String, String> sendBlock = await constructSendBlock(
privateKey: privateKey,
amountRaw: amountRaw,
destinationAddress: destinationAddress,
);
return await processBlock(sendBlock, "send");
}
Future<String> processBlock(Map<String, String> block, String subtype) async {
final headers = {"Content-Type": "application/json"};
final processBody = jsonEncode({
"action": "process",
"json_block": "true",
"subtype": subtype,
"block": block,
});
final processResponse = await http.post(
_node!.uri,
headers: headers,
body: processBody,
);
final Map<String, dynamic> decoded = json.decode(processResponse.body) as Map<String, dynamic>;
if (decoded.containsKey("error")) {
throw Exception("Received error ${decoded["error"]}");
}
// return the hash of the transaction:
return decoded["hash"].toString();
}
Future<Map<String, String>> constructSendBlock({
required String privateKey,
required String amountRaw,
required String destinationAddress,
BigInt? balanceAfterTx,
String? previousHash,
}) async {
try {
// our address:
final String publicAddress = NanoUtil.privateKeyToAddress(privateKey);
// first get the current account balance:
if (balanceAfterTx == null) {
final BigInt currentBalance = (await getBalance(publicAddress)).currentBalance;
final BigInt txAmount = BigInt.parse(amountRaw);
balanceAfterTx = currentBalance - txAmount;
}
// get the account info (we need the frontier and representative):
final headers = {"Content-Type": "application/json"};
final infoBody = jsonEncode({
"action": "account_info",
"representative": "true",
"account": publicAddress,
});
final infoResponse = await http.post(
_node!.uri,
headers: headers,
body: infoBody,
);
String frontier = jsonDecode(infoResponse.body)["frontier"].toString();
// override if provided:
if (previousHash != null) {
frontier = previousHash;
}
final String representative = jsonDecode(infoResponse.body)["representative"].toString();
// link = destination address:
final String link = NanoAccounts.extractPublicKey(destinationAddress);
final String linkAsAccount = destinationAddress;
// construct the send block:
Map<String, String> sendBlock = {
"type": "state",
"account": publicAddress,
"previous": frontier,
"representative": representative,
"balance": balanceAfterTx.toString(),
"link": link,
};
// sign the send block:
final String hash = NanoBlocks.computeStateHash(
NanoAccountType.NANO,
sendBlock["account"]!,
sendBlock["previous"]!,
sendBlock["representative"]!,
BigInt.parse(sendBlock["balance"]!),
sendBlock["link"]!,
);
final String signature = NanoSignatures.signBlock(hash, privateKey);
// get PoW for the send block:
final String work = await requestWork(frontier);
sendBlock["link_as_account"] = linkAsAccount;
sendBlock["signature"] = signature;
sendBlock["work"] = work;
// ready to post send block:
return sendBlock;
} catch (e) {
print(e);
rethrow;
}
}
Future<void> receiveBlock({
required String blockHash,
required String source,
required String amountRaw,
required String destinationAddress,
required String privateKey,
}) async {
bool openBlock = false;
final headers = {
"Content-Type": "application/json",
};
// first check if the account is open:
// get the account info (we need the frontier and representative):
final infoBody = jsonEncode({
"action": "account_info",
"representative": "true",
"account": destinationAddress,
});
final infoResponse = await http.post(
_node!.uri,
headers: headers,
body: infoBody,
);
final infoData = jsonDecode(infoResponse.body);
if (infoData["error"] != null) {
// account is not open yet, we need to create an open block:
openBlock = true;
}
// first get the account balance:
final balanceBody = jsonEncode({
"action": "account_balance",
"account": destinationAddress,
});
final balanceResponse = await http.post(
_node!.uri,
headers: headers,
body: balanceBody,
);
final balanceData = jsonDecode(balanceResponse.body);
final BigInt currentBalance = BigInt.parse(balanceData["balance"].toString());
final BigInt txAmount = BigInt.parse(amountRaw);
final BigInt balanceAfterTx = currentBalance + txAmount;
String frontier = infoData["frontier"].toString();
String representative = infoData["representative"].toString();
if (openBlock) {
// we don't have a representative set yet:
representative = DEFAULT_REPRESENTATIVE;
}
// link = send block hash:
final String link = blockHash;
// this "linkAsAccount" is meaningless:
final String linkAsAccount = NanoAccounts.createAccount(NanoAccountType.NANO, blockHash);
// construct the receive block:
Map<String, String> receiveBlock = {
"type": "state",
"account": destinationAddress,
"previous":
openBlock ? "0000000000000000000000000000000000000000000000000000000000000000" : frontier,
"representative": representative,
"balance": balanceAfterTx.toString(),
"link": link,
"link_as_account": linkAsAccount,
};
// sign the receive block:
final String hash = NanoBlocks.computeStateHash(
NanoAccountType.NANO,
receiveBlock["account"]!,
receiveBlock["previous"]!,
receiveBlock["representative"]!,
BigInt.parse(receiveBlock["balance"]!),
receiveBlock["link"]!,
);
final String signature = NanoSignatures.signBlock(hash, privateKey);
// get PoW for the receive block:
String? work;
if (openBlock) {
work = await requestWork(NanoAccounts.extractPublicKey(destinationAddress));
} else {
work = await requestWork(frontier);
}
receiveBlock["link_as_account"] = linkAsAccount;
receiveBlock["signature"] = signature;
receiveBlock["work"] = work;
// process the receive block:
final processBody = jsonEncode({
"action": "process",
"json_block": "true",
"subtype": "receive",
"block": receiveBlock,
});
final processResponse = await http.post(
_node!.uri,
headers: headers,
body: processBody,
);
final Map<String, dynamic> decoded = json.decode(processResponse.body) as Map<String, dynamic>;
if (decoded.containsKey("error")) {
throw Exception("Received error ${decoded["error"]}");
}
}
// returns the number of blocks received:
Future<int> confirmAllReceivable({
required String destinationAddress,
required String privateKey,
}) async {
final receivableResponse = await http.post(_node!.uri,
headers: {"Content-Type": "application/json"},
body: jsonEncode({
"action": "receivable",
"account": destinationAddress,
"count": "-1",
"source": true,
}));
final receivableData = await jsonDecode(receivableResponse.body);
if (receivableData["blocks"] == "" || receivableData["blocks"] == null) {
return 0;
}
dynamic blocks;
if (receivableData["blocks"] is List<dynamic>) {
var listBlocks = receivableData["blocks"] as List<dynamic>;
if (listBlocks.isEmpty) {
return 0;
}
blocks = {for (var block in listBlocks) block['hash']: block};
} else {
blocks = receivableData["blocks"] as Map<String, dynamic>;
}
blocks = blocks as Map<String, dynamic>;
// confirm all receivable blocks:
for (final blockHash in blocks.keys) {
final block = blocks[blockHash];
final String amountRaw = block["amount"] as String;
final String source = block["source"] as String;
await receiveBlock(
blockHash: blockHash,
source: source,
amountRaw: amountRaw,
privateKey: privateKey,
destinationAddress: destinationAddress,
);
// a bit of a hack:
await Future<void>.delayed(const Duration(seconds: 2));
}
return blocks.keys.length;
}
Future<dynamic> getTransactionDetails(String transactionHash) async {
throw UnimplementedError();
}
void stop() {
subscription?.cancel();
}
Future<List<NanoTransactionModel>> fetchTransactions(String address) async {
try {
final response = await http.post(_node!.uri,
headers: {"Content-Type": "application/json"},
body: jsonEncode({
"action": "account_history",
"account": address,
"count": "250", // TODO: pick a number
// "raw": true,
}));
final data = await jsonDecode(response.body);
final transactions = data["history"] is List ? data["history"] as List<dynamic> : [];
// Map the transactions list to NanoTransactionModel using the factory
// reversed so that the DateTime is correct when local_timestamp is absent
return transactions.reversed
.map<NanoTransactionModel>((transaction) => NanoTransactionModel.fromJson(transaction))
.toList();
} catch (e) {
print(e);
return [];
}
}
}