generic changenow impl

lib/services/exchange/change_now/change_now_api.dart

@@ -11,6 +11,7 @@ import 'package:stackwallet/models/exchange/change_now/exchange_transaction.dart
 import 'package:stackwallet/models/exchange/change_now/exchange_transaction_status.dart';
 import 'package:stackwallet/models/exchange/change_now/fixed_rate_market.dart';
 import 'package:stackwallet/models/exchange/response_objects/currency.dart';
+import 'package:stackwallet/models/exchange/response_objects/range.dart';
 import 'package:stackwallet/services/exchange/exchange_response.dart';
 import 'package:stackwallet/utilities/logger.dart';
 
@@ -266,6 +267,46 @@ class ChangeNowAPI {
     }
   }
 
+  /// The API endpoint returns minimal payment amount and maximum payment amount
+  /// required to make an exchange. If you try to exchange less than minimum or
+  /// more than maximum, the transaction will most likely fail. Any pair of
+  /// assets has minimum amount and some of pairs have maximum amount.
+  Future<ExchangeResponse<Range>> getRange({
+    required String fromTicker,
+    required String toTicker,
+    required bool isFixedRate,
+    String? apiKey,
+  }) async {
+    Map<String, dynamic>? params = {"api_key": apiKey ?? kChangeNowApiKey};
+
+    final uri = _buildUri(
+        "/exchange-range${isFixedRate ? "/fixed-rate" : ""}/${fromTicker}_$toTicker",
+        params);
+
+    try {
+      final jsonObject = await _makeGetRequest(uri);
+
+      final json = Map<String, dynamic>.from(jsonObject as Map);
+      return ExchangeResponse(
+        value: Range(
+          max: Decimal.tryParse(json["maxAmount"] as String? ?? ""),
+          min: Decimal.tryParse(json["minAmount"] as String? ?? ""),
+        ),
+      );
+    } catch (e, s) {
+      Logging.instance.log(
+        "getRange exception: $e\n$s",
+        level: LogLevel.Error,
+      );
+      return ExchangeResponse(
+        exception: ExchangeException(
+          e.toString(),
+          ExchangeExceptionType.generic,
+        ),
+      );
+    }
+  }
+
   /// Get estimated amount of [toTicker] cryptocurrency to receive
   /// for [fromAmount] of [fromTicker]
   Future<ExchangeResponse<EstimatedExchangeAmount>> getEstimatedExchangeAmount({
@@ -309,6 +350,59 @@ class ChangeNowAPI {
     }
   }
 
+  /// Get estimated amount of [toTicker] cryptocurrency to receive
+  /// for [fromAmount] of [fromTicker]
+  Future<ExchangeResponse<EstimatedExchangeAmount>>
+      getEstimatedExchangeAmountFixedRate({
+    required String fromTicker,
+    required String toTicker,
+    required Decimal fromAmount,
+    required bool reversed,
+    String? apiKey,
+  }) async {
+    Map<String, dynamic> params = {"api_key": apiKey ?? kChangeNowApiKey};
+
+    late final Uri uri;
+    if (reversed) {
+      uri = _buildUri(
+        "/exchange-deposit/fixed-rate/${fromAmount.toString()}/${fromTicker}_$toTicker",
+        params,
+      );
+    } else {
+      uri = _buildUri(
+        "/exchange-amount/fixed-rate/${fromAmount.toString()}/${fromTicker}_$toTicker",
+        params,
+      );
+    }
+
+    try {
+      // simple json object is expected here
+      final json = await _makeGetRequest(uri);
+
+      try {
+        final value = EstimatedExchangeAmount.fromJson(
+            Map<String, dynamic>.from(json as Map));
+        return ExchangeResponse(value: value);
+      } catch (_) {
+        return ExchangeResponse(
+          exception: ExchangeException(
+            "Failed to serialize $json",
+            ExchangeExceptionType.serializeResponseError,
+          ),
+        );
+      }
+    } catch (e, s) {
+      Logging.instance.log("getEstimatedExchangeAmount exception: $e\n$s",
+          level: LogLevel.Error);
+      return ExchangeResponse(
+        exception: ExchangeException(
+          e.toString(),
+          ExchangeExceptionType.generic,
+        ),
+      );
+    }
+  }
+
   // old v1 version
   /// This API endpoint returns fixed-rate estimated exchange amount of
   /// [toTicker] cryptocurrency to receive for [fromAmount] of [fromTicker]

lib/services/exchange/change_now/change_now_exchange.dart

@@ -1,10 +1,13 @@
 import 'package:decimal/decimal.dart';
+import 'package:stackwallet/models/exchange/change_now/estimated_exchange_amount.dart';
 import 'package:stackwallet/models/exchange/response_objects/currency.dart';
 import 'package:stackwallet/models/exchange/response_objects/pair.dart';
 import 'package:stackwallet/models/exchange/response_objects/range.dart';
 import 'package:stackwallet/models/exchange/response_objects/trade.dart';
+import 'package:stackwallet/services/exchange/change_now/change_now_api.dart';
 import 'package:stackwallet/services/exchange/exchange.dart';
 import 'package:stackwallet/services/exchange/exchange_response.dart';
+import 'package:uuid/uuid.dart';
 
 class ChangeNowExchange extends Exchange {
   @override
@@ -25,8 +28,10 @@ class ChangeNowExchange extends Exchange {
   Future<ExchangeResponse<List<Currency>>> getAllCurrencies(
     bool fixedRate,
   ) async {
-    // TODO: implement getAllCurrencies
-    throw UnimplementedError();
+    return await ChangeNowAPI.instance.getAvailableCurrencies(
+      fixedRate: fixedRate ? true : null,
+      active: true,
+    );
   }
 
   @override
@@ -41,19 +46,41 @@ class ChangeNowExchange extends Exchange {
     String to,
     Decimal amount,
     bool fixedRate,
+    bool reversed,
   ) async {
-    // TODO: implement getEstimate
-    throw UnimplementedError();
+    late final ExchangeResponse<EstimatedExchangeAmount> response;
+    if (fixedRate) {
+      response =
+          await ChangeNowAPI.instance.getEstimatedExchangeAmountFixedRate(
+        fromTicker: from,
+        toTicker: to,
+        fromAmount: amount,
+        reversed: reversed,
+      );
+    } else {
+      response = await ChangeNowAPI.instance.getEstimatedExchangeAmount(
+        fromTicker: from,
+        toTicker: to,
+        fromAmount: amount,
+      );
+    }
+    if (response.exception != null) {
+      return ExchangeResponse(exception: response.exception);
+    }
+    return ExchangeResponse(value: response.value?.estimatedAmount);
   }
 
   @override
-  Future<ExchangeResponse<Range>> getMinMaxExchangeAmounts(
+  Future<ExchangeResponse<Range>> getRange(
     String from,
     String to,
     bool fixedRate,
   ) async {
-    // TODO: implement getMinMaxExchangeAmounts
-    throw UnimplementedError();
+    return await ChangeNowAPI.instance.getRange(
+      fromTicker: from,
+      toTicker: to,
+      isFixedRate: fixedRate,
+    );
   }
 
   @override
@@ -67,8 +94,76 @@ class ChangeNowExchange extends Exchange {
 
   @override
   Future<ExchangeResponse<Trade>> getTrade(String tradeId) async {
-    // TODO: implement getTrade
-    throw UnimplementedError();
+    final response =
+        await ChangeNowAPI.instance.getTransactionStatus(id: tradeId);
+    if (response.exception != null) {
+      return ExchangeResponse(exception: response.exception);
+    }
+    final t = response.value!;
+    final timestamp = DateTime.tryParse(t.createdAt) ?? DateTime.now();
+
+    final trade = Trade(
+      uuid: const Uuid().v1(),
+      tradeId: tradeId,
+      rateType: "",
+      direction: "",
+      timestamp: timestamp,
+      updatedAt: DateTime.tryParse(t.updatedAt) ?? timestamp,
+      payInCurrency: t.fromCurrency,
+      payInAmount: t.expectedSendAmountDecimal,
+      payInAddress: t.payinAddress,
+      payInNetwork: "",
+      payInExtraId: t.payinExtraId,
+      payInTxid: "",
+      payOutCurrency: t.toCurrency,
+      payOutAmount: t.expectedReceiveAmountDecimal,
+      payOutAddress: t.payoutAddress,
+      payOutNetwork: "",
+      payOutExtraId: t.payoutExtraId,
+      payOutTxid: "",
+      refundAddress: t.refundAddress,
+      refundExtraId: t.refundExtraId,
+      status: t.status.name,
+    );
+
+    return ExchangeResponse(value: trade);
+  }
+
+  @override
+  Future<ExchangeResponse<Trade>> updateTrade(Trade trade) async {
+    final response =
+        await ChangeNowAPI.instance.getTransactionStatus(id: trade.tradeId);
+    if (response.exception != null) {
+      return ExchangeResponse(exception: response.exception);
+    }
+    final t = response.value!;
+    final timestamp = DateTime.tryParse(t.createdAt) ?? DateTime.now();
+
+    final _trade = Trade(
+      uuid: trade.uuid,
+      tradeId: trade.tradeId,
+      rateType: "",
+      direction: "",
+      timestamp: timestamp,
+      updatedAt: DateTime.tryParse(t.updatedAt) ?? timestamp,
+      payInCurrency: t.fromCurrency,
+      payInAmount: t.expectedSendAmountDecimal,
+      payInAddress: t.payinAddress,
+      payInNetwork: "",
+      payInExtraId: t.payinExtraId,
+      payInTxid: "",
+      payOutCurrency: t.toCurrency,
+      payOutAmount: t.expectedReceiveAmountDecimal,
+      payOutAddress: t.payoutAddress,
+      payOutNetwork: "",
+      payOutExtraId: t.payoutExtraId,
+      payOutTxid: "",
+      refundAddress: t.refundAddress,
+      refundExtraId: t.refundExtraId,
+      status: t.status.name,
+    );
+
+    return ExchangeResponse(value: _trade);
   }
 
   @override

lib/services/exchange/exchange.dart

@@ -18,10 +18,11 @@ abstract class Exchange {
   Future<ExchangeResponse<List<Pair>>> getAllPairs(bool fixedRate);
 
   Future<ExchangeResponse<Trade>> getTrade(String tradeId);
+  Future<ExchangeResponse<Trade>> updateTrade(Trade trade);
 
   Future<ExchangeResponse<List<Trade>>> getTrades();
 
-  Future<ExchangeResponse<Range>> getMinMaxExchangeAmounts(
+  Future<ExchangeResponse<Range>> getRange(
     String from,
     String to,
     bool fixedRate,
@@ -32,6 +33,7 @@ abstract class Exchange {
     String to,
     Decimal amount,
     bool fixedRate,
+    bool reversed,
   );
 
   Future<ExchangeResponse<Trade>> createTrade({

lib/services/exchange/simpleswap/simpleswap_api.dart

@@ -334,6 +334,7 @@ class SimpleSwapAPI {
   Future<ExchangeResponse<Trade>> getExchange({
     required String exchangeId,
     String? apiKey,
+    Trade? oldTrade,
   }) async {
     final uri = _buildUri(
       "/get_exchange",
@@ -349,7 +350,7 @@ class SimpleSwapAPI {
       final json = Map<String, dynamic>.from(jsonObject as Map);
       final ts = DateTime.parse(json["timestamp"] as String);
       final trade = Trade(
-        uuid: const Uuid().v1(),
+        uuid: oldTrade?.uuid ?? const Uuid().v1(),
         tradeId: json["id"] as String,
         rateType: json["type"] as String,
         direction: "direct",

lib/services/exchange/simpleswap/simpleswap_exchange.dart

@@ -73,6 +73,7 @@ class SimpleSwapExchange extends Exchange {
     String to,
     Decimal amount,
     bool fixedRate,
+    bool reversed,
   ) async {
     final response = await SimpleSwapAPI.instance.getEstimated(
       isFixedRate: fixedRate,
@@ -88,7 +89,7 @@ class SimpleSwapExchange extends Exchange {
   }
 
   @override
-  Future<ExchangeResponse<Range>> getMinMaxExchangeAmounts(
+  Future<ExchangeResponse<Range>> getRange(
     String from,
     String to,
     bool fixedRate,
@@ -114,6 +115,14 @@ class SimpleSwapExchange extends Exchange {
     return await SimpleSwapAPI.instance.getExchange(exchangeId: tradeId);
   }
 
+  @override
+  Future<ExchangeResponse<Trade>> updateTrade(Trade trade) async {
+    return await SimpleSwapAPI.instance.getExchange(
+      exchangeId: trade.tradeId,
+      oldTrade: trade,
+    );
+  }
+
   @override
   Future<ExchangeResponse<List<Trade>>> getTrades() async {
     // TODO: implement getTrades