Merge pull request #3586 from vitorpamplona/claude/nip29-message-pinning-elzck9

NIP-29 message pinning: UI bar, moderation events, and relay group integration

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/model/nip29RelayGroups/RelayGroupChannel.kt

@@ -31,6 +31,7 @@ import com.vitorpamplona.quartz.nip29RelayGroups.GroupId
 import com.vitorpamplona.quartz.nip29RelayGroups.metadata.GroupAdminsEvent
 import com.vitorpamplona.quartz.nip29RelayGroups.metadata.GroupMembersEvent
 import com.vitorpamplona.quartz.nip29RelayGroups.metadata.GroupMetadataEvent
+import com.vitorpamplona.quartz.nip29RelayGroups.metadata.GroupPinnedEvent
 import com.vitorpamplona.quartz.nip29RelayGroups.tags.GroupAdminTag
 import com.vitorpamplona.quartz.utils.cache.LargeCache
 import kotlinx.coroutines.flow.MutableStateFlow
@@ -70,6 +71,14 @@ class RelayGroupChannel(
         private set
     private var adminsUpdatedAt: Long = 0
 
+    /**
+     * Relay-signed pinned message ids (kind 39005), in the relay's display order.
+     * Pinning replaces the whole list, so this is always the full current set.
+     */
+    var pinnedEventIds: List<HexKey> = emptyList()
+        private set
+    private var pinnedUpdatedAt: Long = 0
+
     /**
      * Members ∪ admins, recomputed only when a roster event lands. [memberCount] and the discovery
      * feed read this per note / per recomposition, so caching it avoids rebuilding the set each read.
@@ -158,6 +167,17 @@ class RelayGroupChannel(
         updateChannelInfo()
     }
 
+    fun updatePinned(event: GroupPinnedEvent) {
+        // Only newer lists supersede; equal-or-older is dropped so a duplicate
+        // arrival isn't reprocessed (no redundant emit).
+        if (event.createdAt <= pinnedUpdatedAt) return
+        pinnedEventIds = event.pinnedEventIds()
+        pinnedUpdatedAt = event.createdAt
+        updateChannelInfo()
+    }
+
+    fun isPinned(eventId: HexKey): Boolean = eventId in pinnedEventIds
+
     /**
      * The shareable NIP-19 `naddr` coordinate for this group's metadata (kind
      * 39000, authored by the relay's own key, with the host relay as a hint), or

commons/src/jvmTest/kotlin/com/vitorpamplona/amethyst/commons/model/nip29RelayGroups/RelayGroupChannelTest.kt

@@ -26,6 +26,7 @@ import com.vitorpamplona.quartz.nip29RelayGroups.GroupId
 import com.vitorpamplona.quartz.nip29RelayGroups.metadata.GroupAdminsEvent
 import com.vitorpamplona.quartz.nip29RelayGroups.metadata.GroupMembersEvent
 import com.vitorpamplona.quartz.nip29RelayGroups.metadata.GroupMetadataEvent
+import com.vitorpamplona.quartz.nip29RelayGroups.metadata.GroupPinnedEvent
 import com.vitorpamplona.quartz.utils.EventFactory
 import kotlin.test.Test
 import kotlin.test.assertEquals
@@ -79,6 +80,70 @@ class RelayGroupChannelTest {
         return EventFactory.create("00".repeat(32), relaySelf, createdAt, GroupAdminsEvent.KIND, tags, "", "22".repeat(64)) as GroupAdminsEvent
     }
 
+    private val msg1 = "11".repeat(32)
+    private val msg2 = "22".repeat(32)
+    private val msg3 = "33".repeat(32)
+
+    private fun pinned(
+        createdAt: Long,
+        vararg eventIds: String,
+    ): GroupPinnedEvent {
+        val tags = (listOf(arrayOf("d", gid)) + eventIds.map { arrayOf("e", it) }).toTypedArray()
+        return EventFactory.create("00".repeat(32), relaySelf, createdAt, GroupPinnedEvent.KIND, tags, "", "22".repeat(64)) as GroupPinnedEvent
+    }
+
+    @Test
+    fun pinnedListFoldsInOrderAndReportsMembership() {
+        val c = channel()
+        assertTrue(c.pinnedEventIds.isEmpty())
+        assertFalse(c.isPinned(msg1))
+
+        c.updatePinned(pinned(100, msg1, msg2))
+
+        assertEquals(listOf(msg1, msg2), c.pinnedEventIds)
+        assertTrue(c.isPinned(msg1))
+        assertTrue(c.isPinned(msg2))
+        assertFalse(c.isPinned(msg3))
+    }
+
+    @Test
+    fun pinListIsFullyReplacedByNewerEvent() {
+        val c = channel()
+        c.updatePinned(pinned(100, msg1, msg2))
+        // A newer list drops msg1, keeps msg2, adds msg3 — the whole set is replaced.
+        c.updatePinned(pinned(200, msg2, msg3))
+
+        assertEquals(listOf(msg2, msg3), c.pinnedEventIds)
+        assertFalse(c.isPinned(msg1))
+        assertTrue(c.isPinned(msg3))
+    }
+
+    @Test
+    fun clearingPinsWithEmptyNewerList() {
+        val c = channel()
+        c.updatePinned(pinned(100, msg1))
+        c.updatePinned(pinned(200))
+        assertTrue(c.pinnedEventIds.isEmpty())
+        assertFalse(c.isPinned(msg1))
+    }
+
+    @Test
+    fun stalePinEventDoesNotSupersede() {
+        val c = channel()
+        c.updatePinned(pinned(200, msg1, msg2))
+        // An OLDER pin list arrives late — ignore it.
+        c.updatePinned(pinned(100, msg3))
+        assertEquals(listOf(msg1, msg2), c.pinnedEventIds)
+    }
+
+    @Test
+    fun equalCreatedAtPinDoesNotResupersede() {
+        val c = channel()
+        c.updatePinned(pinned(100, msg1, msg2))
+        c.updatePinned(pinned(100, msg3))
+        assertEquals(listOf(msg1, msg2), c.pinnedEventIds)
+    }
+
     @Test
     fun placeholderNoteCarriesChannelGathererAndIsStable() {
         val c = channel()