hash-wallet/lib/exchange/provider/exolix_exchange_provider.dart

import 'dart:convert';

import 'package:cake_wallet/.secrets.g.dart' as secrets;
import 'package:cake_wallet/core/lightning_invoice_service.dart';
import 'package:cake_wallet/exchange/exchange_provider_description.dart';
import 'package:cake_wallet/exchange/limits.dart';
import 'package:cake_wallet/exchange/provider/exchange_provider.dart';
import 'package:cake_wallet/exchange/trade.dart';
import 'package:cake_wallet/exchange/trade_not_found_exception.dart';
import 'package:cake_wallet/exchange/trade_request.dart';
import 'package:cake_wallet/exchange/trade_state.dart';
import 'package:cake_wallet/wallet_type_utils.dart';
import 'package:cw_core/utils/proxy_wrapper.dart';
import 'package:cw_core/crypto_currency.dart';
import 'package:cw_core/utils/print_verbose.dart';
import 'package:cake_wallet/utils/exchange_provider_logger.dart';

class ExolixExchangeProvider extends ExchangeProvider {
  ExolixExchangeProvider();

  static final apiKey = isMoneroOnly ? secrets.exolixMoneroApiKey : secrets.exolixCakeWalletApiKey;
  static const apiBaseUrl = 'exolix.com';
  static const transactionsPath = '/api/v2/transactions';
  static const ratePath = '/api/v2/rate';

  @override
  String get title => 'Exolix';

  @override
  bool get isAvailable => true;

  @override
  bool get isEnabled => true;

  @override
  bool get supportsFixedRate => true;

  @override
  ExchangeProviderDescription get description => ExchangeProviderDescription.exolix;

  @override
  Future<bool> checkIsAvailable() async => true;

  @override
  Future<Limits?> fetchLimits({
    required CryptoCurrency from,
    required CryptoCurrency to,
    required bool isFixedRateMode,
  }) async {
    final params = <String, String>{
      'rateType': _getRateType(isFixedRateMode),
      'amount': '1',
      'apiToken': apiKey,
    };

    if (isFixedRateMode) {
      params['coinFrom'] = _normalizeCurrency(to);
      params['coinTo'] = _normalizeCurrency(_overrideFromCryptoCurrency(from));
      params['networkFrom'] = _networkFor(to);
      params['networkTo'] = _networkFor(from);
    } else {
      params['coinFrom'] = _normalizeCurrency(_overrideFromCryptoCurrency(from));
      params['coinTo'] = _normalizeCurrency(to);
      params['networkFrom'] = _networkFor(from);
      params['networkTo'] = _networkFor(to);
    }

    // Maximum of 2 attempts to fetch limits
    for (int i = 0; i < 2; i++) {
      final uri = Uri.https(apiBaseUrl, ratePath, params);
      final response = await ProxyWrapper().get(clearnetUri: uri);
      
      
      if (response.statusCode == 200) {
        final responseJSON = json.decode(response.body) as Map<String, dynamic>;
        final minAmount = responseJSON['minAmount'];
        final maxAmount = responseJSON['maxAmount'];
        return Limits(min: _toDouble(minAmount), max: _toDouble(maxAmount));
      } else if (response.statusCode == 422) {
        final errorResponse = json.decode(response.body) as Map<String, dynamic>;
        if (errorResponse.containsKey('minAmount')) {
          params['amount'] = errorResponse['minAmount'].toString();
          continue;
        }
        throw Exception('Error 422: ${errorResponse['message'] ?? 'Unknown error'}');
      } else {
        throw Exception('Unexpected HTTP status: ${response.statusCode}');
      }
    }

    throw Exception('Failed to fetch limits after retrying.');
  }

  @override
  Future<double> fetchRate({
    required CryptoCurrency from,
    required CryptoCurrency to,
    required double amount,
    required bool isFixedRateMode,
    required bool isReceiveAmount
  }) async {
    try {
      if (amount == 0) return 0.0;

      final params = {
        'coinFrom': _normalizeCurrency(_overrideFromCryptoCurrency(from)),
        'coinTo': _normalizeCurrency(to),
        'networkFrom': _networkFor(from),
        'networkTo': _networkFor(to),
        'rateType': _getRateType(isFixedRateMode),
        'apiToken': apiKey,
      };

      if (isReceiveAmount)
        params['withdrawalAmount'] = amount.toString();
      else
        params['amount'] = amount.toString();

      final uri = Uri.https(apiBaseUrl, ratePath, params);
      final response = await ProxyWrapper().get(clearnetUri: uri);
      
      final responseJSON = json.decode(response.body) as Map<String, dynamic>;

      if (response.statusCode != 200) {
        final message = responseJSON['message'] as String?;
        
        ExchangeProviderLogger.logError(
          provider: description,
          function: 'fetchRate',
          error: Exception(message ?? 'Unknown error'),
          stackTrace: StackTrace.current,
          requestData: {
            'from': from.title,
            'to': to.title,
            'amount': amount,
            'isFixedRateMode': isFixedRateMode,
            'isReceiveAmount': isReceiveAmount,
            'params': params,
            'url': uri.toString(),
          },
        );
        
        throw Exception(message);
      }

      final rate = double.tryParse(responseJSON['rate']?.toString() ?? '') ?? 0.0;

      ExchangeProviderLogger.logSuccess(
        provider: description,
        function: 'fetchRate',
        requestData: {
          'from': from.title,
          'to': to.title,
          'amount': amount,
          'isFixedRateMode': isFixedRateMode,
          'isReceiveAmount': isReceiveAmount,
          'params': params,
          'url': uri.toString(),
        },
        responseData: {
          'rate': rate,
          'statusCode': response.statusCode,
          'responseJSON': responseJSON,
        },
      );

      return rate;
    } catch (e, s) {
      ExchangeProviderLogger.logError(
        provider: description,
        function: 'fetchRate',
        error: e,
        stackTrace: s,
        requestData: {
          'from': from.title,
          'to': to.title,
          'amount': amount,
          'isFixedRateMode': isFixedRateMode,
          'isReceiveAmount': isReceiveAmount,
        },
      );
      printV(e.toString());
      printV(s.toString());
      return 0.0;
    }
  }

  @override
  Future<Trade> createTrade({
    required TradeRequest request,
    required bool isFixedRateMode,
    required bool isSendAll,
  }) async {
    final headers = {'Content-Type': 'application/json'};
    final body = {
      'coinFrom': _normalizeCurrency(_overrideFromCryptoCurrency(request.fromCurrency)),
      'coinTo': _normalizeCurrency(_overrideToCryptoCurrency(request.toCurrency, request.toAddress)),
      'networkFrom': _networkFor(request.fromCurrency),
      'networkTo': _networkFor(request.toCurrency),
      'withdrawalAddress': await _normalizeAddress(request.toAddress),
      'refundAddress': await _normalizeAddress(request.refundAddress),
      'rateType': _getRateType(isFixedRateMode),
      'apiToken': apiKey,
    };

    if (isFixedRateMode)
      body['withdrawalAmount'] = request.toAmount;
    else
      body['amount'] = request.fromAmount;

    final uri = Uri.https(apiBaseUrl, transactionsPath);
    final response = await ProxyWrapper().post(
      clearnetUri: uri,
      headers: headers,
      body: json.encode(body),
    );

    if (response.statusCode == 400) {
      final responseJSON = json.decode(response.body) as Map<String, dynamic>;
      final errors = responseJSON['error'] as Map<String, String>;
      final errorMessage = errors.values.join(', ');
      
      ExchangeProviderLogger.logError(
        provider: description,
        function: 'createTrade',
        error: Exception(errorMessage),
        stackTrace: StackTrace.current,
        requestData: {
          'from': request.fromCurrency.title,
          'to': request.toCurrency.title,
          'fromAmount': request.fromAmount,
          'toAmount': request.toAmount,
          'toAddress': request.toAddress,
          'refundAddress': request.refundAddress,
          'isFixedRateMode': isFixedRateMode,
          'isSendAll': isSendAll,
          'body': body,
          'url': uri.toString(),
        },
      );
      
      throw Exception(errorMessage);
    }

    if (response.statusCode != 200 && response.statusCode != 201) {
      ExchangeProviderLogger.logError(
        provider: description,
        function: 'createTrade',
        error: Exception('Unexpected http status: ${response.statusCode}'),
        stackTrace: StackTrace.current,
        requestData: {
          'from': request.fromCurrency.title,
          'to': request.toCurrency.title,
          'fromAmount': request.fromAmount,
          'toAmount': request.toAmount,
          'toAddress': request.toAddress,
          'refundAddress': request.refundAddress,
          'isFixedRateMode': isFixedRateMode,
          'isSendAll': isSendAll,
          'body': body,
          'url': uri.toString(),
        },
      );
      throw Exception('Unexpected http status: ${response.statusCode}');
    }

    final responseJSON = json.decode(response.body) as Map<String, dynamic>;
    final id = responseJSON['id'] as String;
    final inputAddress = responseJSON['depositAddress'] as String;
    final refundAddress = responseJSON['refundAddress'] as String?;
    final extraId = responseJSON['depositExtraId'] as String?;
    final payoutAddress = responseJSON['withdrawalAddress'] as String;
    final amount = responseJSON['amount'].toString();
    final receiveAmount = responseJSON['amountTo']?.toString();

    ExchangeProviderLogger.logSuccess(
      provider: description,
      function: 'createTrade',
      requestData: {
        'from': request.fromCurrency.title,
        'to': request.toCurrency.title,
        'fromAmount': request.fromAmount,
        'toAmount': request.toAmount,
        'toAddress': request.toAddress,
        'refundAddress': request.refundAddress,
        'isFixedRateMode': isFixedRateMode,
        'isSendAll': isSendAll,
        'body': body,
        'url': uri.toString(),
      },
      responseData: {
        'id': id,
        'inputAddress': inputAddress,
        'refundAddress': refundAddress,
        'extraId': extraId,
        'payoutAddress': payoutAddress,
        'amount': amount,
        'receiveAmount': receiveAmount,
        'statusCode': response.statusCode,
        'responseJSON': responseJSON,
      },
    );

    return Trade(
      id: id,
      from: request.fromCurrency,
      to: request.toCurrency,
      provider: description,
      inputAddress: inputAddress,
      refundAddress: refundAddress,
      extraId: extraId,
      createdAt: DateTime.now(),
      amount: amount,
      receiveAmount: receiveAmount ?? request.toAmount,
      state: TradeState.created,
      payoutAddress: payoutAddress,
      userCurrencyFromRaw: '${request.fromCurrency.title}_${request.fromCurrency.tag ?? ''}',
      userCurrencyToRaw: '${request.toCurrency.title}_${request.toCurrency.tag ?? ''}',
      isSendAll: isSendAll,
    );
  }

  @override
  Future<Trade> findTradeById({required String id}) async {
    final findTradeByIdPath = '$transactionsPath/$id';
    final uri = Uri.https(apiBaseUrl, findTradeByIdPath);
    final response = await ProxyWrapper().get(clearnetUri: uri);
    
    if (response.statusCode == 404) throw TradeNotFoundException(id, provider: description);

    if (response.statusCode == 400) {
      final responseJSON = json.decode(response.body) as Map<String, dynamic>;
      final errors = responseJSON['errors'] as Map<String, String>;
      final errorMessage = errors.values.join(', ');

      throw TradeNotFoundException(id, provider: description, description: errorMessage);
    }

    if (response.statusCode != 200)
      throw Exception('Unexpected http status: ${response.statusCode}');

    final responseJSON = json.decode(response.body) as Map<String, dynamic>;

    // Parsing 'from' currency
    final coinFrom = responseJSON['coinFrom']['coinCode'] as String;
    final coinFromNetwork = responseJSON['coinFrom']['network'] as String?;
    final _normalizedFromNetwork = _normalizeNetworkType(coinFromNetwork ?? '');
    final fromTag = coinFrom.toUpperCase() == _normalizedFromNetwork.toUpperCase() ? null : coinFromNetwork;
    final from = CryptoCurrency.safeParseCurrencyFromString(coinFrom, tag: fromTag);

    // Parsing 'to' currency
    final coinTo = responseJSON['coinTo']['coinCode'] as String;
    final coinToNetwork = responseJSON['coinTo']['network'] as String?;
    final _normalizedToNetwork = _normalizeNetworkType(coinToNetwork ?? '');
    final toTag = coinTo.toUpperCase() == _normalizedToNetwork.toUpperCase() ? null : coinToNetwork;
    final to = CryptoCurrency.safeParseCurrencyFromString(coinTo, tag: toTag);

    final inputAddress = responseJSON['depositAddress'] as String;
    final amount = responseJSON['amount'].toString();
    final status = responseJSON['status'] as String;
    final extraId = responseJSON['depositExtraId'] as String?;
    final outputTransaction = responseJSON['hashOut']['hash'] as String?;
    final payoutAddress = responseJSON['withdrawalAddress'] as String;

    return Trade(
        id: id,
        from: from,
        to: to,
        provider: description,
        inputAddress: inputAddress,
        amount: amount,
        state: TradeState.deserialize(raw: _prepareStatus(status)),
        extraId: extraId,
        outputTransaction: outputTransaction,
        payoutAddress: payoutAddress,
      userCurrencyFromRaw: '${coinFrom.toUpperCase()}' + '_' + '${fromTag?.toUpperCase() ?? ''}',
      userCurrencyToRaw: '${coinTo.toUpperCase()}' + '_' + '${toTag?.toUpperCase() ?? ''}',
    );
  }

  String _getRateType(bool isFixedRate) => isFixedRate ? 'fixed' : 'float';

  String _prepareStatus(String status) {
    switch (status) {
      case 'deleted':
      case 'error':
        return 'overdue';
      default:
        return status;
    }
  }

  String _networkFor(CryptoCurrency currency) {
    switch (currency) {
      case CryptoCurrency.arb:
        return 'ARBITRUM';
      case CryptoCurrency.btcln:
        return 'LIGHTNING';
      default:
        return currency.tag != null ? _normalizeTag(currency.tag!) : currency.title;
    }
  }

  String _normalizeNetworkType(String network) {
    return switch (network.toUpperCase()) {
      'ARBITRUM' => 'ARB',
      _ => network,
    };
  }

  CryptoCurrency _overrideFromCryptoCurrency(CryptoCurrency currency) {
    if (currency == CryptoCurrency.zec)
      return CryptoCurrency.zaddr; // Sending is always shielded zcash
    return currency;
  }

  CryptoCurrency _overrideToCryptoCurrency(CryptoCurrency currency, String address) {
    if (RegExp(r'u1[a-zA-Z0-9]{100,300}').hasMatch(address) && currency == CryptoCurrency.zec)
      return CryptoCurrency.zaddr; // If the user pastes a unified address use shielded zcash
    return currency;
  }

  String _normalizeCurrency(CryptoCurrency currency) {
    switch (currency) {
      case CryptoCurrency.nano:
        return 'XNO';
      case CryptoCurrency.bttc:
        return 'BTT';
      case CryptoCurrency.zec:
        return 'ZEC';
      case CryptoCurrency.zaddr:
        return 'ZEC-SHIELDED';
      default:
        return currency.title;
    }
  }

  String _normalizeTag(String tag) {
    switch (tag) {
      case 'POLY':
        return 'Polygon';
        case 'ARB':
        return 'Arbitrum';
      default:
        return tag;
    }
  }

  Future<String> _normalizeAddress(String address) async {
    if (address.startsWith('bitcoincash:'))
      return address.replaceFirst('bitcoincash:', '');

    // Lightning addresses
    if(address.contains("@"))
      return await getBolt11FromLightingAddress(address) ?? address;

    return address;
  }


  static double? _toDouble(dynamic value) {
    if (value is int) {
      return value.toDouble();
    } else if (value is double) {
      return value;
    } else if (value is String) {
      return double.tryParse(value);
    }
    return null;
  }
}