Fix Medium severity performance findings (PERF-17 to PERF-21) (#325)

* Fix Medium severity performance findings (PERF-17 to PERF-21)

This commit addresses the following performance findings:
- PERF-17: Implemented a message queue in `HermesWsClient` using `ConcurrentLinkedQueue`. If the WebSocket is disconnected, messages are queued and flushed upon a successful connection (`onOpen`).
- PERF-18: Added exponential backoff to `safeApiCall` for 5xx and IO exceptions, reducing the load on a struggling server.
- PERF-19: Optimized Kanban task filtering by performing `groupBy` upfront inside a `remember` block and passing item keys to `LazyColumn`, avoiding O(C×T) calculation per recomposition.
- PERF-20: Updated `getLogs` API in `HermesApiService` to accept `lines` and `limit` query params to truncate logs early, avoiding potential JSON parsing OOMs with large log files.
- PERF-21: Optimized drawer entry generation in `Navigation.kt` by grouping navigation items inside a `remember` block.

Fixes #282

* Fix Medium severity performance findings (PERF-17 to PERF-21)

This commit addresses the following performance findings:
- PERF-17: Implemented a message queue in `HermesWsClient` using `ConcurrentLinkedQueue`. If the WebSocket is disconnected, messages are queued and flushed upon a successful connection (`onOpen`).
- PERF-18: Added exponential backoff to `safeApiCall` for 5xx and IO exceptions, reducing the load on a struggling server.
- PERF-19: Optimized Kanban task filtering by performing `groupBy` upfront inside a `remember` block and passing item keys to `LazyColumn`, avoiding O(C×T) calculation per recomposition.
- PERF-20: Updated `getLogs` API in `HermesApiService` to accept `lines` and `limit` query params to truncate logs early, avoiding potential JSON parsing OOMs with large log files.
- PERF-21: Optimized drawer entry generation in `Navigation.kt` by grouping navigation items inside a `remember` block.

Fixes #282

* Fix Medium severity performance findings (PERF-17 to PERF-21)

This commit addresses the following performance findings:
- PERF-17: Implemented a message queue in `HermesWsClient` using `ConcurrentLinkedQueue`. If the WebSocket is disconnected, messages are queued and flushed upon a successful connection (`onOpen`).
- PERF-18: Added exponential backoff to `safeApiCall` for 5xx and IO exceptions, reducing the load on a struggling server.
- PERF-19: Optimized Kanban task filtering by performing `groupBy` upfront inside a `remember` block and passing item keys to `LazyColumn`, avoiding O(C×T) calculation per recomposition.
- PERF-20: Updated `getLogs` API in `HermesApiService` to accept `lines` and `limit` query params to truncate logs early, avoiding potential JSON parsing OOMs with large log files.
- PERF-21: Optimized drawer entry generation in `Navigation.kt` by grouping navigation items inside a `remember` block.

Fixes #282

* fix: resolve ktlint formatting issues in KanbanScreen.kt and Navigation.kt

* fix: fix ktlint import ordering in HermesWsClient.kt

---------

Co-authored-by: M57 <hy4ri@users.noreply.github.com>

app/src/main/java/com/m57/hermescontrol/Navigation.kt

@@ -346,6 +346,8 @@ fun MainNavigation(sessionId: String? = null) {
     val bottomNavItems = resolveBottomNavItems(bottomNavItemsState)
     val bottomNavKeys = remember(bottomNavItems) { bottomNavItems.mapTo(mutableSetOf()) { it.key } }
 
+    val drawerEntriesBySection = remember { DRAWER_ENTRIES.groupBy { it.section } }
+
     // Sync primary screens to NavigationController
     LaunchedEffect(bottomNavKeys) {
         NavigationController.updatePrimaryScreens(bottomNavKeys)
@@ -419,9 +421,7 @@ fun MainNavigation(sessionId: String? = null) {
                             color = MaterialTheme.colorScheme.onSurfaceVariant,
                             fontWeight = FontWeight.SemiBold,
                         )
-                        DRAWER_ENTRIES
+                        drawerEntriesBySection[section]?.forEach { entry ->
-                            .filter { it.section == section }
-                            .forEach { entry ->
                             NavigationDrawerItem(
                                 icon = { Icon(entry.icon, contentDescription = null) },
                                 label = { Text(stringResource(entry.labelRes)) },

app/src/main/java/com/m57/hermescontrol/data/remote/HermesApiService.kt

@@ -212,7 +212,10 @@ interface HermesApiService {
     suspend fun getModelOptions(): Response<ModelOptionsResponse>
 
     @GET("api/logs")
-    suspend fun getLogs(): Response<LogResponse>
+    suspend fun getLogs(
+        @Query("limit") limit: Int? = null,
+        @Query("lines") lines: Int? = null,
+    ): Response<LogResponse>
 
     @GET("api/dashboard/plugins/hub")
     suspend fun getPlugins(): Response<PluginsHubResponse>

app/src/main/java/com/m57/hermescontrol/data/remote/NetworkResult.kt

@@ -1,5 +1,6 @@
 package com.m57.hermescontrol.data.remote
 
+import kotlinx.coroutines.delay
 import retrofit2.Response
 import java.io.IOException
 
@@ -68,6 +69,8 @@ suspend inline fun <reified T> safeApiCall(
             } else {
                 val code = response.code()
                 if (code in 500..599 && attempt < retries) {
+                    val backoff = 500L * (1 shl attempt)
+                    delay(backoff)
                     continue
                 }
                 return NetworkResult.Failure(mapHttpError(code))
@@ -82,6 +85,8 @@ suspend inline fun <reified T> safeApiCall(
                     ),
                 )
             }
+            val backoff = 500L * (1 shl attempt)
+            delay(backoff)
         } catch (e: Exception) {
             return NetworkResult.Failure(
                 NetworkError.Unknown(

app/src/main/java/com/m57/hermescontrol/data/ws/HermesWsClient.kt

@@ -28,6 +28,7 @@ import okhttp3.Request
 import okhttp3.Response
 import okhttp3.WebSocket
 import okhttp3.WebSocketListener
+import java.util.concurrent.ConcurrentLinkedQueue
 import java.util.concurrent.TimeUnit
 import java.util.concurrent.atomic.AtomicBoolean
 import java.util.concurrent.atomic.AtomicInteger
@@ -64,6 +65,7 @@ object HermesWsClient {
     private val requestId = AtomicInteger(0)
     private val connected = AtomicBoolean(false)
     private val intentionalClose = AtomicBoolean(false)
+    private val messageQueue = ConcurrentLinkedQueue<String>()
 
     @Volatile
     private var webSocket: WebSocket? = null
@@ -170,7 +172,13 @@ object HermesWsClient {
         // prompts (PromptSubmit params include the `text` field) — never
         // stream to logcat in release builds.
         if (BuildConfig.DEBUG) Log.d(TAG, "→ $json")
-        webSocket?.send(json) ?: Log.w(TAG, "send() called while disconnected")
+        val ws = webSocket
+        if (ws != null && connected.get()) {
+            ws.send(json)
+        } else {
+            Log.d(TAG, "WS disconnected — queuing message")
+            messageQueue.add(json)
+        }
         return id
     }
 
@@ -243,17 +251,25 @@ object HermesWsClient {
 
     private class WsListenerImpl : WebSocketListener() {
         override fun onOpen(
-            ws: WebSocket,
+            webSocket: WebSocket,
             response: Response,
         ) {
             Log.i(TAG, "WebSocket opened")
             connected.set(true)
             _connectionStatus.value = ConnectionStatus.CONNECTED
             currentBackoff = INITIAL_BACKOFF_MS
+
+            while (messageQueue.isNotEmpty()) {
+                val msg = messageQueue.poll()
+                if (msg != null) {
+                    if (BuildConfig.DEBUG) Log.d(TAG, "→ (queued) $msg")
+                    webSocket.send(msg)
+                }
+            }
         }
 
         override fun onMessage(
-            ws: WebSocket,
+            webSocket: WebSocket,
             text: String,
         ) {
             // B2 (Jun 18 2026, kanban t_8884db16): incoming WS text contains
@@ -264,16 +280,16 @@ object HermesWsClient {
         }
 
         override fun onClosing(
-            ws: WebSocket,
+            webSocket: WebSocket,
             code: Int,
             reason: String,
         ) {
             Log.d(TAG, "WebSocket closing: $code $reason")
-            ws.close(code, reason)
+            webSocket.close(code, reason)
         }
 
         override fun onClosed(
-            ws: WebSocket,
+            webSocket: WebSocket,
             code: Int,
             reason: String,
         ) {
@@ -284,7 +300,7 @@ object HermesWsClient {
         }
 
         override fun onFailure(
-            ws: WebSocket,
+            webSocket: WebSocket,
             t: Throwable,
             response: Response?,
         ) {

app/src/main/java/com/m57/hermescontrol/ui/kanban/KanbanScreen.kt

@@ -72,6 +72,11 @@ fun KanbanScreen(
                     task.assignedTo?.contains(query, ignoreCase = true) == true
             }
         }
+
+    val tasksByColumn =
+        remember(filteredTasks) {
+            filteredTasks.groupBy { it.status.lowercase() }
+        }
     var showAddTaskDialog by remember { mutableStateOf(false) }
 
     LaunchedEffect(Unit) {
@@ -149,13 +154,13 @@ fun KanbanScreen(
                                     contentPadding = PaddingValues(16.dp),
                                     horizontalArrangement = Arrangement.spacedBy(16.dp),
                                 ) {
-                                    items(state.columns, key = { it.name }) { column ->
+                                    items(state.columns.size, key = {
+                                            index ->
+                                        state.columns[index].name
+                                    }) { columnIndex ->
+                                        val column = state.columns[columnIndex]
                                         val colName = column.name
-                                        val colTasks =
+                                        val colTasks = tasksByColumn[colName.lowercase()] ?: emptyList()
-                                            filteredTasks.filter {
-                                                it.status.equals(colName, ignoreCase = true)
-                                            }
-                                        val columnIndex = state.columns.indexOf(column)
                                         val prevColumn = state.columns.getOrNull(columnIndex - 1)
                                         val nextColumn = state.columns.getOrNull(columnIndex + 1)
 

app/src/main/java/com/m57/hermescontrol/ui/logs/LogsViewModel.kt

@@ -23,7 +23,7 @@ class LogsViewModel : ViewModel(), ToastHost {
 
     fun loadLogs() {
         safeLaunchLoad(
-            apiCall = { safeApiCall { ApiClient.hermesApi.getLogs() } },
+            apiCall = { safeApiCall { ApiClient.hermesApi.getLogs(lines = 1000) } },
             onStart = { _uiState.update { it.copy(isLoading = true, errorMessage = null) } },
             onSuccess = { data ->
                 val body = data

app/src/test/java/com/m57/hermescontrol/E2eIntegrationTest.kt

@@ -851,7 +851,7 @@ class E2eIntegrationTest {
     @Test
     fun testLogsListing_success() =
         runTest {
-            coEvery { mockApiService.getLogs() } returns
+            coEvery { mockApiService.getLogs(lines = 1000) } returns
                 Response.success(LogResponse(listOf("Log line 1", "Log line 2")))
 
             val viewModel = LogsViewModel()