From 88d11aafec809398915791ddc8b98bd5033065d6 Mon Sep 17 00:00:00 2001
From: James Rich <2199651+jamesarich@users.noreply.github.com>
Date: Sat, 21 Mar 2026 09:25:23 -0500
Subject: [PATCH] fix: Update messaging feature with contact item keys and MQTT
 limits (#4871)

---
 .../org/meshtastic/core/database/dao/PacketDao.kt  |  1 +
 .../core/network/repository/MQTTRepositoryImpl.kt  | 14 +++++++++++++-
 .../feature/messaging/ui/contact/Contacts.kt       |  5 +++--
 3 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/core/database/src/commonMain/kotlin/org/meshtastic/core/database/dao/PacketDao.kt b/core/database/src/commonMain/kotlin/org/meshtastic/core/database/dao/PacketDao.kt
index ae6506cbf..ba0f34056 100644
--- a/core/database/src/commonMain/kotlin/org/meshtastic/core/database/dao/PacketDao.kt
+++ b/core/database/src/commonMain/kotlin/org/meshtastic/core/database/dao/PacketDao.kt
@@ -76,6 +76,7 @@ interface PacketDao {
     ) latest ON p.contact_key = latest.contact_key AND p.received_time = latest.max_time
     WHERE (p.myNodeNum = 0 OR p.myNodeNum = (SELECT myNodeNum FROM my_node))
         AND p.port_num = 1 AND p.filtered = 0
+    GROUP BY p.contact_key
     ORDER BY p.received_time DESC
     """,
     )
diff --git a/core/network/src/commonMain/kotlin/org/meshtastic/core/network/repository/MQTTRepositoryImpl.kt b/core/network/src/commonMain/kotlin/org/meshtastic/core/network/repository/MQTTRepositoryImpl.kt
index e6711f9db..aa0da5efc 100644
--- a/core/network/src/commonMain/kotlin/org/meshtastic/core/network/repository/MQTTRepositoryImpl.kt
+++ b/core/network/src/commonMain/kotlin/org/meshtastic/core/network/repository/MQTTRepositoryImpl.kt
@@ -32,6 +32,8 @@ import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.callbackFlow
 import kotlinx.coroutines.flow.first
 import kotlinx.coroutines.launch
+import kotlinx.coroutines.sync.Semaphore
+import kotlinx.coroutines.sync.withPermit
 import kotlinx.serialization.json.Json
 import okio.ByteString.Companion.toByteString
 import org.koin.core.annotation.Single
@@ -58,6 +60,7 @@ class MQTTRepositoryImpl(
     private val json = Json { ignoreUnknownKeys = true }
     private val scope = CoroutineScope(Dispatchers.Default + SupervisorJob())
     private var clientJob: Job? = null
+    private val publishSemaphore = Semaphore(20)
 
     override fun disconnect() {
         Logger.i { "MQTT Disconnecting" }
@@ -162,6 +165,15 @@ class MQTTRepositoryImpl(
     @OptIn(ExperimentalUnsignedTypes::class)
     override fun publish(topic: String, data: ByteArray, retained: Boolean) {
         Logger.d { "MQTT publishing message to topic $topic (size: ${data.size} bytes, retained: $retained)" }
-        client?.publish(retain = retained, qos = Qos.AT_LEAST_ONCE, topic = topic, payload = data.toUByteArray())
+        scope.launch {
+            publishSemaphore.withPermit {
+                client?.publish(
+                    retain = retained,
+                    qos = Qos.AT_LEAST_ONCE,
+                    topic = topic,
+                    payload = data.toUByteArray(),
+                )
+            }
+        }
     }
 }
diff --git a/feature/messaging/src/androidMain/kotlin/org/meshtastic/feature/messaging/ui/contact/Contacts.kt b/feature/messaging/src/androidMain/kotlin/org/meshtastic/feature/messaging/ui/contact/Contacts.kt
index e002459c7..028b5be82 100644
--- a/feature/messaging/src/androidMain/kotlin/org/meshtastic/feature/messaging/ui/contact/Contacts.kt
+++ b/feature/messaging/src/androidMain/kotlin/org/meshtastic/feature/messaging/ui/contact/Contacts.kt
@@ -57,6 +57,7 @@ import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import androidx.paging.LoadState
 import androidx.paging.compose.LazyPagingItems
 import androidx.paging.compose.collectAsLazyPagingItems
+import androidx.paging.compose.itemKey
 import com.google.accompanist.permissions.ExperimentalPermissionsApi
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.collectLatest
@@ -566,7 +567,7 @@ private fun LazyListScope.contactListPlaceholdersItems(
     channels: ChannelSet?,
     haptic: HapticFeedback,
 ) {
-    items(count = placeholders.size, key = { index -> placeholders[index].contactKey }) { index ->
+    items(count = placeholders.size, key = { index -> "${placeholders[index].contactKey}_placeholder" }) { index ->
         val contact = placeholders[index]
         ContactItem(
             contact = contact,
@@ -593,7 +594,7 @@ private fun LazyListScope.contactListPagedItems(
     channels: ChannelSet?,
     haptic: HapticFeedback,
 ) {
-    items(count = contacts.itemCount, key = { index -> contacts[index]?.contactKey ?: index }) { index ->
+    items(count = contacts.itemCount, key = contacts.itemKey { it.contactKey }) { index ->
         contacts[index]?.let { contact ->
             ContactItem(
                 contact = contact,