Handle burning man selection height edge-cases

If trader A's block height is 134 his burning man selection height is
120, and if trader B's block height is 135 his burning man selection
height is 130.

The current burning man selection height verification code doesn't
handle these edge-cases.

core/src/main/java/bisq/core/dao/burningman/DelayedPayoutTxReceiverService.java

@@ -217,7 +217,7 @@ private static int getSnapshotHeight(int genesisHeight, int height, int grid) {
 
     // Borrowed from DaoStateSnapshotService. We prefer to not reuse to avoid dependency to an unrelated domain.
     @VisibleForTesting
-    static int getSnapshotHeight(int genesisHeight, int height, int grid, int minSnapshotHeight) {
+    public static int getSnapshotHeight(int genesisHeight, int height, int grid, int minSnapshotHeight) {
         if (height > (genesisHeight + 3 * grid)) {
             int ratio = (int) Math.round(height / (double) grid);
             return Math.max(minSnapshotHeight, ratio * grid - grid);

core/src/main/java/bisq/core/offer/OpenOfferManager.java

@@ -47,6 +47,7 @@
 import bisq.core.trade.ClosedTradableManager;
 import bisq.core.trade.bisq_v1.TransactionResultHandler;
 import bisq.core.trade.model.TradableList;
+import bisq.core.trade.protocol.bisq_v1.tasks.maker.MakerProcessesInputsForDepositTxRequest;
 import bisq.core.trade.statistics.TradeStatisticsManager;
 import bisq.core.user.Preferences;
 import bisq.core.user.User;
@@ -857,7 +858,10 @@ private void handleOfferAvailabilityRequest(OfferAvailabilityRequest request, No
                 checkArgument(takersBurningManSelectionHeight > 0, "takersBurningManSelectionHeight must not be 0");
 
                 int makersBurningManSelectionHeight = delayedPayoutTxReceiverService.getBurningManSelectionHeight();
-                checkArgument(takersBurningManSelectionHeight == makersBurningManSelectionHeight,
+
+                boolean areBurningManSelectionHeightsValid = MakerProcessesInputsForDepositTxRequest
+                        .verifyBurningManSelectionHeight(takersBurningManSelectionHeight, makersBurningManSelectionHeight);
+                checkArgument(areBurningManSelectionHeightsValid,
                         "takersBurningManSelectionHeight does no match makersBurningManSelectionHeight. " +
                                 "takersBurningManSelectionHeight=" + takersBurningManSelectionHeight + "; makersBurningManSelectionHeight=" + makersBurningManSelectionHeight);
             } catch (Throwable t) {

core/src/main/java/bisq/core/trade/protocol/bisq_v1/tasks/maker/MakerProcessesInputsForDepositTxRequest.java

@@ -17,6 +17,7 @@
 
 package bisq.core.trade.protocol.bisq_v1.tasks.maker;
 
+import bisq.core.dao.burningman.DelayedPayoutTxReceiverService;
 import bisq.core.exceptions.TradePriceOutOfToleranceException;
 import bisq.core.offer.Offer;
 import bisq.core.support.dispute.mediation.mediator.Mediator;
@@ -83,8 +84,12 @@ protected void run() {
             checkArgument(takersBurningManSelectionHeight > 0, "takersBurningManSelectionHeight must not be 0");
 
             int makersBurningManSelectionHeight = processModel.getDelayedPayoutTxReceiverService().getBurningManSelectionHeight();
-            checkArgument(takersBurningManSelectionHeight == makersBurningManSelectionHeight,
+
+            boolean areBurningManSelectionHeightsValid = verifyBurningManSelectionHeight(
+                    takersBurningManSelectionHeight, makersBurningManSelectionHeight);
+            checkArgument(areBurningManSelectionHeightsValid,
                     "takersBurningManSelectionHeight does no match makersBurningManSelectionHeight");
+
             processModel.setBurningManSelectionHeight(makersBurningManSelectionHeight);
 
             // We set the taker fee only in the processModel yet not in the trade as the tx was only created but not
@@ -132,4 +137,21 @@ protected void run() {
             failed(t);
         }
     }
+
+    public static boolean verifyBurningManSelectionHeight(int takersBurningManSelectionHeight,
+                                                   int makersBurningManSelectionHeight) {
+        if (takersBurningManSelectionHeight == makersBurningManSelectionHeight) {
+            return true;
+
+        } else if (takersBurningManSelectionHeight < makersBurningManSelectionHeight) {
+            int takersNextBlockBurningManSelectionHeight =
+                    takersBurningManSelectionHeight + DelayedPayoutTxReceiverService.SNAPSHOT_SELECTION_GRID_SIZE;
+            return takersNextBlockBurningManSelectionHeight == makersBurningManSelectionHeight;
+
+        } else {
+            int makersNextBlockBurningManSelectionHeight =
+                    makersBurningManSelectionHeight + DelayedPayoutTxReceiverService.SNAPSHOT_SELECTION_GRID_SIZE;
+            return takersBurningManSelectionHeight == makersNextBlockBurningManSelectionHeight;
+        }
+    }
 }

core/src/test/java/bisq/core/trade/protocol/bisq_v1/tasks/maker/MakerProcessesInputsForDepositTxRequestTest.java

@@ -0,0 +1,44 @@
+package bisq.core.trade.protocol.bisq_v1.tasks.maker;
+
+import bisq.core.dao.burningman.DelayedPayoutTxReceiverService;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+public class MakerProcessesInputsForDepositTxRequestTest {
+    private static final int GENESIS_HEIGHT = 102;
+    private static final int GRID_SIZE = DelayedPayoutTxReceiverService.SNAPSHOT_SELECTION_GRID_SIZE;
+
+    @Test
+    void burningManSelectionHeightSameBlock() {
+        assertEquals(130,
+                DelayedPayoutTxReceiverService.getSnapshotHeight(GENESIS_HEIGHT, 139, GRID_SIZE, 0));
+        boolean isValid = MakerProcessesInputsForDepositTxRequest
+                .verifyBurningManSelectionHeight(130, 130);
+        assertTrue(isValid);
+    }
+
+    @Test
+    void burningManSelectionHeightMakerOneBlockInFuture() {
+        assertEquals(120,
+                DelayedPayoutTxReceiverService.getSnapshotHeight(GENESIS_HEIGHT, 134, GRID_SIZE, 0));
+        assertEquals(130,
+                DelayedPayoutTxReceiverService.getSnapshotHeight(GENESIS_HEIGHT, 135, GRID_SIZE, 0));
+        boolean isValid = MakerProcessesInputsForDepositTxRequest
+                .verifyBurningManSelectionHeight(120, 130);
+        assertTrue(isValid);
+    }
+
+    @Test
+    void burningManSelectionHeightTakerOneBlockInFuture() {
+        assertEquals(120,
+                DelayedPayoutTxReceiverService.getSnapshotHeight(GENESIS_HEIGHT, 134, GRID_SIZE, 0));
+        assertEquals(130,
+                DelayedPayoutTxReceiverService.getSnapshotHeight(GENESIS_HEIGHT, 135, GRID_SIZE, 0));
+        boolean isValid = MakerProcessesInputsForDepositTxRequest
+                .verifyBurningManSelectionHeight(130, 120);
+        assertTrue(isValid);
+    }
+}