feat(chat): integrate fast mode toggle into generation controls dropdown (#1093)

app/src/test/java/com/m57/hermescontrol/ui/chat/ChatModelSwitchDelegateTest.kt

@@ -40,7 +40,7 @@ class ChatModelSwitchDelegateTest {
                         slug = "openai",
                         name = "OpenAI",
                         models = listOf("gpt-4o"),
-                        capabilities = mapOf("gpt-4o" to ModelCapabilities(reasoning = true)),
+                        capabilities = mapOf("gpt-4o" to ModelCapabilities(fast = true, reasoning = true)),
                     ),
                 ),
         )
@@ -138,4 +138,73 @@ class ChatModelSwitchDelegateTest {
             assertNull(uiState.value.modelSwitchConfirmMessage)
             assertEquals("anthropic/claude-3", uiState.value.currentSessionModel)
         }
+
+    @Test
+    fun toggleFastMode_sendsConfigSetFast_andUpdatesOnAck() =
+        testScope.runTest {
+            delegate.preloadModelOptions()
+            advanceUntilIdle()
+
+            // Switch to model with fast capability
+            delegate.sendSlashModel("openai", "gpt-4o")
+            advanceUntilIdle()
+            sentMethods.clear()
+            sentParams.clear()
+
+            assertTrue(uiState.value.currentModelCapabilities?.fast == true)
+            assertFalse(uiState.value.fastMode)
+            assertFalse(uiState.value.isFastModeChanging)
+
+            delegate.toggleFastMode()
+            advanceUntilIdle()
+            assertTrue(uiState.value.isFastModeChanging)
+            assertFalse(uiState.value.fastMode) // Still unconfirmed!
+            assertEquals(listOf(WsMethods.CONFIG_SET), sentMethods)
+            assertEquals("fast", sentParams.first()["key"])
+            assertEquals("fast", sentParams.first()["value"])
+            assertEquals("runtime-1", sentParams.first()["session_id"])
+
+            // Backend acknowledges
+            delegate.handleConfigSetResult("req-1", mapOf("key" to "fast", "value" to "fast"))
+            assertTrue(uiState.value.fastMode)
+            assertFalse(uiState.value.isFastModeChanging)
+
+            // Toggle off
+            delegate.toggleFastMode()
+            advanceUntilIdle()
+            assertTrue(uiState.value.isFastModeChanging)
+            assertEquals("normal", sentParams.last()["value"])
+
+            delegate.handleConfigSetResult("req-2", mapOf("key" to "fast", "value" to "normal"))
+            assertFalse(uiState.value.fastMode)
+            assertFalse(uiState.value.isFastModeChanging)
+        }
+
+    @Test
+    fun toggleFastMode_whenRejectedByBackend_clearsChangingAndLatchesUnavailable() =
+        testScope.runTest {
+            delegate.preloadModelOptions()
+            advanceUntilIdle()
+            delegate.sendSlashModel("openai", "gpt-4o")
+            advanceUntilIdle()
+            sentMethods.clear()
+            sentParams.clear()
+            assertTrue(uiState.value.currentModelCapabilities?.fast == true)
+
+            delegate.toggleFastMode()
+            advanceUntilIdle()
+            assertTrue(uiState.value.isFastModeChanging)
+
+            // Backend returns error indicating fast mode not available
+            delegate.handleConfigSetError("req-1", mapOf("message" to "fast mode is not available for this model"))
+            assertFalse(uiState.value.isFastModeChanging)
+            assertFalse(uiState.value.fastMode)
+            assertEquals(false, uiState.value.currentModelCapabilities?.fast)
+
+            // Further toggle attempts are no-ops
+            val sentCount = sentMethods.size
+            delegate.toggleFastMode()
+            advanceUntilIdle()
+            assertEquals(sentCount, sentMethods.size)
+        }
 }

app/src/test/java/com/m57/hermescontrol/ui/chat/ChatViewModelTest.kt

@@ -2951,6 +2951,92 @@ class ChatViewModelTest {
             assertEquals("nous/tencent/hy3:free", viewModel.uiState.value.currentSessionModel)
         }
 
+    @Test
+    fun testSessionInfo_hydratesFastModeState() =
+        runTest {
+            stubEmptySessionRests("session-a")
+            val (viewModel, _) = createViewModelWithSession()
+            advanceUntilIdle()
+
+            assertFalse(viewModel.uiState.value.fastMode)
+
+            // Fast = true in session.info
+            mockEventsFlow.emit(
+                WsEvent.SessionInfo(
+                    mapOf("fast" to true, "service_tier" to "priority"),
+                ),
+            )
+            advanceUntilIdle()
+            assertTrue(viewModel.uiState.value.fastMode)
+            assertFalse(viewModel.uiState.value.isFastModeChanging)
+
+            // Fast = false / normal in session.info
+            mockEventsFlow.emit(
+                WsEvent.SessionInfo(
+                    mapOf("fast" to false, "service_tier" to "normal"),
+                ),
+            )
+            advanceUntilIdle()
+            assertFalse(viewModel.uiState.value.fastMode)
+
+            // Partial session.info without fast/service_tier does NOT clear state
+            mockEventsFlow.emit(
+                WsEvent.SessionInfo(
+                    mapOf("fast" to true),
+                ),
+            )
+            advanceUntilIdle()
+            assertTrue(viewModel.uiState.value.fastMode)
+
+            mockEventsFlow.emit(
+                WsEvent.SessionInfo(
+                    mapOf("terminal_backend" to "tmux"),
+                ),
+            )
+            advanceUntilIdle()
+            assertTrue(viewModel.uiState.value.fastMode) // preserved!
+        }
+
+    @Test
+    fun testSessionResume_hydratesFastModeState() =
+        runTest {
+            stubEmptySessionRests("session-b")
+            val (viewModel, _) = createViewModelWithSession()
+            var resumeReqId = ""
+            every { HermesWsClient.send(WsMethods.SESSION_RESUME, any(), any()) } answers {
+                val reqId = "resume-req-1"
+                resumeReqId = reqId
+                arg<((String) -> Unit)?>(2)?.invoke(reqId)
+                reqId
+            }
+
+            viewModel.switchSession("session-b")
+            runCurrent()
+
+            // Simulate SESSION_RESUME response with fast=true in info
+            mockEventsFlow.emit(
+                WsEvent.RpcResult(
+                    id = resumeReqId,
+                    result =
+                        mapOf(
+                            "session_id" to "sess-runtime-1",
+                            "resumed" to "session-b",
+                            "info" to
+                                mapOf(
+                                    "model" to "gpt-4o",
+                                    "provider" to "openai",
+                                    "fast" to true,
+                                    "service_tier" to "priority",
+                                ),
+                        ),
+                ),
+            )
+            advanceUntilIdle()
+
+            assertTrue(viewModel.uiState.value.fastMode)
+            assertFalse(viewModel.uiState.value.isFastModeChanging)
+        }
+
     @Test
     fun testResumeNotFound_recoversWithNewSession() =
         runTest {