fix fee calculation taking offer within range

core/src/main/java/haveno/core/api/CoreApi.java

@@ -512,10 +512,11 @@ public class CoreApi {
 
     public void takeOffer(String offerId,
                           String paymentAccountId,
+                          long amountAsLong,
                           Consumer<Trade> resultHandler,
                           ErrorMessageHandler errorMessageHandler) {
         Offer offer = coreOffersService.getOffer(offerId);
-        coreTradesService.takeOffer(offer, paymentAccountId, resultHandler, errorMessageHandler);
+        coreTradesService.takeOffer(offer, paymentAccountId, amountAsLong, resultHandler, errorMessageHandler);
     }
 
     public void confirmPaymentSent(String tradeId,

core/src/main/java/haveno/core/api/CoreTradesService.java

@@ -89,6 +89,7 @@ class CoreTradesService {
 
     void takeOffer(Offer offer,
                    String paymentAccountId,
+                   long amountAsLong,
                    Consumer<Trade> resultHandler,
                    ErrorMessageHandler errorMessageHandler) {
         try {
@@ -101,18 +102,21 @@ class CoreTradesService {
 
             var useSavingsWallet = true;
 
+            // default to offer amount
+            BigInteger amount = amountAsLong == 0 ? offer.getAmount() : BigInteger.valueOf(amountAsLong);
+
             // synchronize access to take offer model // TODO (woodser): to avoid synchronizing, don't use stateful model
             BigInteger takerFee;
             BigInteger fundsNeededForTrade;
             synchronized (takeOfferModel) {
-                takeOfferModel.initModel(offer, paymentAccount, useSavingsWallet);
+                takeOfferModel.initModel(offer, paymentAccount, amount, useSavingsWallet);
                 takerFee = takeOfferModel.getTakerFee();
                 fundsNeededForTrade = takeOfferModel.getFundsNeededForTrade();
                 log.info("Initiating take {} offer, {}", offer.isBuyOffer() ? "buy" : "sell", takeOfferModel);
             }
 
             // take offer
-            tradeManager.onTakeOffer(offer.getAmount(),
+            tradeManager.onTakeOffer(amount,
                     takerFee,
                     fundsNeededForTrade,
                     offer,

core/src/main/java/haveno/core/offer/availability/OfferAvailabilityModel.java

@@ -32,6 +32,8 @@ import haveno.network.p2p.P2PService;
 import lombok.Getter;
 import lombok.Setter;
 
+import java.math.BigInteger;
+
 import javax.annotation.Nullable;
 
 public class OfferAvailabilityModel implements Model {
@@ -54,6 +56,8 @@ public class OfferAvailabilityModel implements Model {
     @Getter
     private String paymentAccountId;
     @Getter
+    private BigInteger tradeAmount;
+    @Getter
     private OfferUtil offerUtil;
     @Getter
     @Setter
@@ -76,6 +80,7 @@ public class OfferAvailabilityModel implements Model {
                                   TradeStatisticsManager tradeStatisticsManager,
                                   boolean isTakerApiUser,
                                   String paymentAccountId,
+                                  BigInteger tradeAmount,
                                   OfferUtil offerUtil) {
         this.offer = offer;
         this.pubKeyRing = pubKeyRing;
@@ -86,6 +91,7 @@ public class OfferAvailabilityModel implements Model {
         this.tradeStatisticsManager = tradeStatisticsManager;
         this.isTakerApiUser = isTakerApiUser;
         this.paymentAccountId = paymentAccountId;
+        this.tradeAmount = tradeAmount;
         this.offerUtil = offerUtil;
     }
 

core/src/main/java/haveno/core/offer/availability/tasks/SendOfferAvailabilityRequest.java

@@ -69,9 +69,9 @@ public class SendOfferAvailabilityRequest extends Task<OfferAvailabilityModel> {
                     offer.getId(),
                     P2PService.getMyNodeAddress(),
                     p2PService.getKeyRing().getPubKeyRing(),
-                    offer.getAmount().longValueExact(),
+                    model.getTradeAmount().longValueExact(),
                     price.getValue(),
-                    HavenoUtils.getTakerFee(offer.getAmount()).longValueExact(),
+                    HavenoUtils.getTakerFee(model.getTradeAmount()).longValueExact(),
                     user.getAccountId(),
                     paymentAccountId,
                     paymentMethodId,

core/src/main/java/haveno/core/offer/takeoffer/TakeOfferModel.java

@@ -92,6 +92,7 @@ public class TakeOfferModel implements Model {
 
     public void initModel(Offer offer,
                           PaymentAccount paymentAccount,
+                          BigInteger tradeAmount,
                           boolean useSavingsWallet) {
         this.clearModel();
         this.offer = offer;
@@ -100,7 +101,7 @@ public class TakeOfferModel implements Model {
         validateModelInputs();
 
         this.useSavingsWallet = useSavingsWallet;
-        this.amount = offer.getAmount().min(BigInteger.valueOf(getMaxTradeLimit()));
+        this.amount = tradeAmount.min(BigInteger.valueOf(getMaxTradeLimit()));
         this.securityDeposit = offer.getDirection() == SELL
                 ? offer.getBuyerSecurityDeposit()
                 : offer.getSellerSecurityDeposit();

core/src/main/java/haveno/core/trade/TradeManager.java

@@ -561,11 +561,11 @@ public class TradeManager implements PersistedDataHost, DecryptedDirectMessageLi
             }
 
             // get expected taker fee
-            BigInteger takerFee = HavenoUtils.getTakerFee(BigInteger.valueOf(offer.getOfferPayload().getAmount()));
+            BigInteger takerFee = HavenoUtils.getTakerFee(BigInteger.valueOf(request.getTradeAmount()));
 
             // create arbitrator trade
             trade = new ArbitratorTrade(offer,
-                    BigInteger.valueOf(offer.getOfferPayload().getAmount()),
+                    BigInteger.valueOf(request.getTradeAmount()),
                     takerFee,
                     offer.getOfferPayload().getPrice(),
                     xmrWalletService,
@@ -630,12 +630,12 @@ public class TradeManager implements PersistedDataHost, DecryptedDirectMessageLi
           openOfferManager.reserveOpenOffer(openOffer);
 
           // get expected taker fee
-          BigInteger takerFee = HavenoUtils.getTakerFee(BigInteger.valueOf(offer.getOfferPayload().getAmount()));
+          BigInteger takerFee = HavenoUtils.getTakerFee(BigInteger.valueOf(request.getTradeAmount()));
 
           Trade trade;
           if (offer.isBuyOffer())
               trade = new BuyerAsMakerTrade(offer,
-                      BigInteger.valueOf(offer.getOfferPayload().getAmount()),
+                      BigInteger.valueOf(request.getTradeAmount()),
                       takerFee,
                       offer.getOfferPayload().getPrice(),
                       xmrWalletService,
@@ -646,7 +646,7 @@ public class TradeManager implements PersistedDataHost, DecryptedDirectMessageLi
                       request.getArbitratorNodeAddress());
           else
               trade = new SellerAsMakerTrade(offer,
-                      BigInteger.valueOf(offer.getOfferPayload().getAmount()),
+                      BigInteger.valueOf(request.getTradeAmount()),
                       takerFee,
                       offer.getOfferPayload().getPrice(),
                       xmrWalletService,
@@ -788,9 +788,10 @@ public class TradeManager implements PersistedDataHost, DecryptedDirectMessageLi
     public void checkOfferAvailability(Offer offer,
                                        boolean isTakerApiUser,
                                        String paymentAccountId,
+                                       BigInteger tradeAmount,
                                        ResultHandler resultHandler,
                                        ErrorMessageHandler errorMessageHandler) {
-        offer.checkOfferAvailability(getOfferAvailabilityModel(offer, isTakerApiUser, paymentAccountId), resultHandler, errorMessageHandler);
+        offer.checkOfferAvailability(getOfferAvailabilityModel(offer, isTakerApiUser, paymentAccountId, tradeAmount), resultHandler, errorMessageHandler);
     }
 
     // First we check if offer is still available then we create the trade with the protocol
@@ -806,7 +807,7 @@ public class TradeManager implements PersistedDataHost, DecryptedDirectMessageLi
 
         checkArgument(!wasOfferAlreadyUsedInTrade(offer.getId()));
 
-        OfferAvailabilityModel model = getOfferAvailabilityModel(offer, isTakerApiUser, paymentAccountId);
+        OfferAvailabilityModel model = getOfferAvailabilityModel(offer, isTakerApiUser, paymentAccountId, amount);
         offer.checkOfferAvailability(model,
                 () -> {
                     if (offer.getState() == Offer.State.AVAILABLE) {
@@ -886,7 +887,7 @@ public class TradeManager implements PersistedDataHost, DecryptedDirectMessageLi
                 processModelServiceProvider.getKeyRing().getPubKeyRing());
     }
 
-    private OfferAvailabilityModel getOfferAvailabilityModel(Offer offer, boolean isTakerApiUser, String paymentAccountId) {
+    private OfferAvailabilityModel getOfferAvailabilityModel(Offer offer, boolean isTakerApiUser, String paymentAccountId, BigInteger tradeAmount) {
         return new OfferAvailabilityModel(
                 offer,
                 keyRing.getPubKeyRing(),
@@ -897,6 +898,7 @@ public class TradeManager implements PersistedDataHost, DecryptedDirectMessageLi
                 tradeStatisticsManager,
                 isTakerApiUser,
                 paymentAccountId,
+                tradeAmount,
                 offerUtil);
     }
 

core/src/main/java/haveno/core/trade/protocol/tasks/MakerSendInitTradeRequest.java

@@ -54,7 +54,7 @@ public class MakerSendInitTradeRequest extends TradeTask {
                     offer.getId(),
                     processModel.getMyNodeAddress(),
                     processModel.getPubKeyRing(),
-                    offer.getAmount().longValueExact(),
+                    trade.getAmount().longValueExact(),
                     trade.getPrice().getValue(),
                     offer.getMakerFee().longValueExact(),
                     trade.getProcessModel().getAccountId(),

daemon/src/main/java/haveno/daemon/grpc/GrpcTradesService.java

@@ -122,6 +122,7 @@ class GrpcTradesService extends TradesImplBase {
         try {
             coreApi.takeOffer(req.getOfferId(),
                     req.getPaymentAccountId(),
+                    req.getAmount(),
                     trade -> {
                         TradeInfo tradeInfo = toTradeInfo(trade);
                         var reply = TakeOfferReply.newBuilder()

desktop/src/main/java/haveno/desktop/main/offer/takeoffer/TakeOfferDataModel.java

@@ -156,6 +156,7 @@ class TakeOfferDataModel extends OfferDataModel {
             tradeManager.checkOfferAvailability(offer,
                     false,
                     paymentAccount.getId(),
+                    this.amount.get(),
                     () -> {
                     },
                     errorMessage -> new Popup().warning(errorMessage).show());

proto/src/main/proto/grpc.proto

@@ -746,6 +746,7 @@ service Trades {
 message TakeOfferRequest {
     string offer_id = 1;
     string payment_account_id = 2;
+    uint64 amount = 3 [jstype = JS_STRING];
 }
 
 message TakeOfferReply {