From 20172fa9d6e8be97f34cbcbb150b4523b817626a Mon Sep 17 00:00:00 2001
From: Brandon McAnsh <git@bmcreations.dev>
Date: Thu, 3 Sep 2026 14:40:25 -0400
Subject: [PATCH] fix(flipcash): treat an unset bill_exchange_data_timeout as
 absent
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bill_exchange_data_timeout is a google.protobuf.Duration, so an unset field
still yields the default instance and the mapper turned that into 0.seconds
rather than null. Guard on hasBillExchangeDataTimeout(), which is how every
other optional message-typed field here is read — see UserProfileMapper's
profilePicture and joinTs, and ChatMetadataMapper's lastMessage.

The two values are not interchangeable downstream. VerifiedState.exchangeDataFor
substitutes a 15 minute default for null but returns null outright for a timeout
of zero, so every user whose flags omitted the field was treated as having
verified exchange data permanently expired: GiveBillTransactor.start refetched
the rate on every bill instead of using the state it already held.

No consumer needed adjusting. Field.BillExchangeDataTimeout already encodes
null as -1 and formats it as "None", and CachedFlags round-trips it as a
nullable Long.
---
 .../flipcash/services/internal/domain/UserFlagsMapper.kt | 4 +++-
 .../kotlin/com/flipcash/services/models/UserFlags.kt     | 3 +++
 .../services/internal/domain/UserFlagsMapperTest.kt      | 9 +++++++++
 3 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/services/flipcash/src/main/kotlin/com/flipcash/services/internal/domain/UserFlagsMapper.kt b/services/flipcash/src/main/kotlin/com/flipcash/services/internal/domain/UserFlagsMapper.kt
index 0156fce551..c55b96d1d4 100644
--- a/services/flipcash/src/main/kotlin/com/flipcash/services/internal/domain/UserFlagsMapper.kt
+++ b/services/flipcash/src/main/kotlin/com/flipcash/services/internal/domain/UserFlagsMapper.kt
@@ -22,7 +22,9 @@ internal class UserFlagsMapper @Inject constructor():
             preferredOnRampProvider = from.preferredOnRampProvider.toDomain().takeIf { it != OnRampProvider.Unknown },
             supportedOnRampProviders = from.supportedOnRampProvidersList.map { it.toDomain() },
             minimumVersion = from.minBuildNumber,
-            billExchangeDataTimeout = from.billExchangeDataTimeout.seconds.toDuration(DurationUnit.SECONDS),
+            billExchangeDataTimeout = if (from.hasBillExchangeDataTimeout()) {
+                from.billExchangeDataTimeout.seconds.toDuration(DurationUnit.SECONDS)
+            } else null,
             newCurrencyPurchaseAmount = Fiat(quarks = from.newCurrencyPurchaseAmount),
             newCurrencyFeeAmount = Fiat(quarks = from.newCurrencyFeeAmount),
             withdrawalFeeAmount = Fiat(quarks = from.withdrawalFeeAmount),
diff --git a/services/flipcash/src/main/kotlin/com/flipcash/services/models/UserFlags.kt b/services/flipcash/src/main/kotlin/com/flipcash/services/models/UserFlags.kt
index 6b4f46e725..fcdac22492 100644
--- a/services/flipcash/src/main/kotlin/com/flipcash/services/models/UserFlags.kt
+++ b/services/flipcash/src/main/kotlin/com/flipcash/services/models/UserFlags.kt
@@ -12,6 +12,9 @@ data class UserFlags(
     val preferredOnRampProvider: OnRampProvider?,
     val supportedOnRampProviders: List<OnRampProvider>,
     val minimumVersion: Int?,
+    // How long a verified exchange rate stays usable for a bill. Absent when the
+    // server hasn't set a timeout (not the same as a zero-length one, which
+    // disables verified exchange data entirely).
     val billExchangeDataTimeout: Duration?,
     val newCurrencyPurchaseAmount: Fiat,
     val newCurrencyFeeAmount: Fiat,
diff --git a/services/flipcash/src/test/kotlin/com/flipcash/services/internal/domain/UserFlagsMapperTest.kt b/services/flipcash/src/test/kotlin/com/flipcash/services/internal/domain/UserFlagsMapperTest.kt
index 12f85c3ed2..b48e78de53 100644
--- a/services/flipcash/src/test/kotlin/com/flipcash/services/internal/domain/UserFlagsMapperTest.kt
+++ b/services/flipcash/src/test/kotlin/com/flipcash/services/internal/domain/UserFlagsMapperTest.kt
@@ -116,6 +116,15 @@ class UserFlagsMapperTest {
         assertEquals(30.seconds, result.billExchangeDataTimeout)
     }
 
+    @Test
+    fun `bill exchange data timeout is null when unset, not zero`() {
+        val proto = userFlags { }
+
+        val result = mapper.map(proto)
+
+        assertNull(result.billExchangeDataTimeout)
+    }
+
     @Test
     fun `maps new currency purchase amount`() {
         val proto = userFlags {