feat(chat): adopt flipcash2 0.18.0 (cover pictures, featured groups, chatter sampling)

apps/flipcash/shared/chat/src/main/kotlin/com/flipcash/shared/chat/internal/RosterStateHolder.kt

@@ -49,6 +49,9 @@ class RosterStateHolder @Inject constructor(
 
             when {
                 incoming <= stored -> continue
+                // The summary is all a membership change carries and all it needs: it edits no
+                // member, so a skipped version here is not a hole in the cached list to repair.
+                change is RosterChange.MembershipChanged -> applyChange(chatId, change)
                 incoming > stored + 1 -> refetch(chatId, stored, incoming)
                 else -> applyChange(chatId, change)
             }
@@ -59,6 +62,8 @@ class RosterStateHolder @Inject constructor(
         when (change) {
             is RosterChange.MemberJoined -> memberDataSource.upsert(chatId, listOf(change.member))
             is RosterChange.MemberLeft -> memberDataSource.deleteMember(chatId, change.userId)
+            // Summary only; the cached member list stays as it is.
+            is RosterChange.MembershipChanged -> Unit
         }
         metadataDataSource.updateRoster(
             chatId = chatId,

apps/flipcash/shared/chat/src/main/kotlin/com/flipcash/shared/chat/internal/delegates/EventStreamDelegate.kt

@@ -433,6 +433,10 @@ class EventStreamDelegate @Inject constructor(
                     // Same best-effort contract as TitleChanged above.
                     metadataDataSource.updatePicture(chatId, metaUpdate.newPicture)
                 }
+                is MetadataUpdate.CoverPictureChanged -> {
+                    // Same best-effort contract as TitleChanged above. Replaces the cached cover.
+                    metadataDataSource.updateCoverPicture(chatId, metaUpdate.newCoverPicture)
+                }
             }
         }
 

apps/flipcash/shared/chat/src/main/kotlin/com/flipcash/shared/chat/internal/delegates/GroupFeedDelegate.kt

@@ -235,6 +235,10 @@ class GroupFeedDelegate @Inject constructor(
                     // of the chat, whether you left from this device or another one.
                     metadataDataSource.clearViewerState(chatId)
                 }
+
+                // No list-level meaning: it edits neither your membership nor the member list.
+                // The summary is applied by RosterStateHolder below.
+                is RosterChange.MembershipChanged -> Unit
             }
         }
         rosterStateHolder.apply(chatId, changes)

apps/flipcash/shared/chat/src/test/kotlin/com/flipcash/shared/chat/RosterStateHolderTest.kt

@@ -60,6 +60,45 @@ class RosterStateHolderTest {
         coEvery { metadataDataSource.getRosterVersion(chatId) } returns version
     }
 
+    @Test
+    fun `a membership change applies the summary and leaves the member list alone`() = runTest {
+        storedVersion(4)
+
+        subject.apply(
+            chatId,
+            listOf(RosterChange.MembershipChanged(RosterSummary(memberCount = 12, version = 5))),
+        )
+
+        coVerify { metadataDataSource.updateRoster(chatId, memberCount = 12, rosterVersion = 5) }
+        coVerify(exactly = 0) { memberDataSource.upsert(any(), any()) }
+        coVerify(exactly = 0) { memberDataSource.deleteMember(any(), any()) }
+    }
+
+    @Test
+    fun `a membership change that skips versions is applied without a refetch`() = runTest {
+        storedVersion(4)
+
+        subject.apply(
+            chatId,
+            listOf(RosterChange.MembershipChanged(RosterSummary(memberCount = 12, version = 9))),
+        )
+
+        coVerify(exactly = 0) { controller.getChat(any(), any()) }
+        coVerify { metadataDataSource.updateRoster(chatId, memberCount = 12, rosterVersion = 9) }
+    }
+
+    @Test
+    fun `a membership change at or below the stored version is dropped`() = runTest {
+        storedVersion(5)
+
+        subject.apply(
+            chatId,
+            listOf(RosterChange.MembershipChanged(RosterSummary(memberCount = 12, version = 5))),
+        )
+
+        coVerify(exactly = 0) { metadataDataSource.updateRoster(any(), any(), any()) }
+    }
+
     @Test
     fun `a join one version ahead is applied`() = runTest {
         storedVersion(4)