fix: higher invoice CLTV offset for Reverse Swaps

Author: michael1011

lib/service/Service.ts

@@ -1188,9 +1188,9 @@ class Service {
       onchainTimeoutBlockDelta,
     );
 
-    // Add 3 blocks to the delta for same currency swaps and 25% for cross chain ones as buffer
+    // Add 15 blocks to the delta for same currency swaps and 25% for cross chain ones as buffer
     lightningTimeoutBlockDelta +=
-      sending === receiving ? 3 : Math.ceil(lightningTimeoutBlockDelta * 0.25);
+      sending === receiving ? 15 : Math.ceil(lightningTimeoutBlockDelta * 0.25);
 
     const rate = getRate(pairRate, side, true);
     const feePercent = this.rateProvider.feeProvider.getPercentageFee(

test/unit/service/Service.spec.ts

@@ -1509,7 +1509,7 @@ describe('Service', () => {
       quoteCurrency: 'BTC',
       orderSide: OrderSide.BUY,
       onchainTimeoutBlockDelta: 1,
-      lightningTimeoutBlockDelta: 4,
+      lightningTimeoutBlockDelta: 16,
       holdInvoiceAmount: invoiceAmount,
       percentageFee: invoiceAmount * mockGetPercentageFeeResult,
     });
@@ -1669,7 +1669,7 @@ describe('Service', () => {
       quoteCurrency: 'BTC',
       orderSide: OrderSide.BUY,
       onchainTimeoutBlockDelta: 1,
-      lightningTimeoutBlockDelta: 4,
+      lightningTimeoutBlockDelta: 16,
       holdInvoiceAmount: invoiceAmount,
       percentageFee: invoiceAmount * mockGetPercentageFeeResult,
     });
@@ -1748,7 +1748,7 @@ describe('Service', () => {
       quoteCurrency: 'BTC',
       orderSide: OrderSide.BUY,
       onchainTimeoutBlockDelta: 1,
-      lightningTimeoutBlockDelta: 4,
+      lightningTimeoutBlockDelta: 16,
       prepayMinerFeeInvoiceAmount: mockGetBaseFeeResult,
       holdInvoiceAmount: invoiceAmount - mockGetBaseFeeResult,
       percentageFee: invoiceAmount * mockGetPercentageFeeResult,