fix(update): bind live download state to dialog and show real-time progress

app/src/main/java/com/m57/hermescontrol/ui/chat/ChatScreen.kt

@@ -600,6 +600,23 @@ fun ChatScreen(
                             ?: error("Application not available")
                     AppUpdateViewModel(app)
                 }
+            val appUpdateState by appUpdateViewModel.state.collectAsStateWithLifecycle()
+
+            val updateLifecycleOwner = androidx.lifecycle.compose.LocalLifecycleOwner.current
+            androidx.compose.runtime.DisposableEffect(updateLifecycleOwner) {
+                val observer =
+                    androidx.lifecycle.LifecycleEventObserver { _, event ->
+                        if (event == androidx.lifecycle.Lifecycle.Event.ON_RESUME) {
+                            if (appUpdateState is AppUpdateState.NeedsUnknownSourcesPermission) {
+                                appUpdateViewModel.resumeInstallAfterPermission()
+                            }
+                        }
+                    }
+                updateLifecycleOwner.lifecycle.addObserver(observer)
+                onDispose {
+                    updateLifecycleOwner.lifecycle.removeObserver(observer)
+                }
+            }
 
             if (UpdateNoticeManager.enabled && !AppUpdateCache.dismissed) {
                 val noticeTag =
@@ -616,8 +633,14 @@ fun ChatScreen(
 
             if (AppUpdateCache.isDialogVisible) {
                 val context = androidx.compose.ui.platform.LocalContext.current
+                val dialogState =
+                    if (appUpdateState !is AppUpdateState.Idle) {
+                        appUpdateState
+                    } else {
+                        updateNotice
+                    }
                 AppUpdateDialog(
-                    state = updateNotice,
+                    state = dialogState,
                     onDismiss = { AppUpdateCache.hideDialog() },
                     onStartUpdate = { appUpdateViewModel.startUpdate() },
                     onCancelDownload = { appUpdateViewModel.cancelDownload() },

app/src/main/java/com/m57/hermescontrol/ui/common/AppUpdateDialog.kt

@@ -29,6 +29,10 @@ import androidx.compose.material3.Surface
 import androidx.compose.material3.Text
 import androidx.compose.material3.TextButton
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.draw.clip
@@ -49,14 +53,19 @@ fun AppUpdateDialog(
     onNeverAskAgain: () -> Unit,
     onOpenSettings: () -> Unit,
 ) {
-    val tag = state.releaseTag().orEmpty()
     val available = state as? AppUpdateState.UpdateAvailable
+    var cachedAvailable by remember { mutableStateOf(available) }
+    if (available != null) {
+        cachedAvailable = available
+    }
+    val currentAvailable = available ?: cachedAvailable
+    val tag = state.releaseTag() ?: currentAvailable?.latestTag.orEmpty()
     val sizeMb =
-        available?.let {
+        currentAvailable?.let {
             val mb = it.sizeBytes / (1024 * 1024.0)
             "%.1f MB".format(mb)
         }
-    val releaseNotes = available?.releaseNotes?.trim().orEmpty()
+    val releaseNotes = currentAvailable?.releaseNotes?.trim().orEmpty()
 
     Dialog(onDismissRequest = onDismiss) {
         Surface(
@@ -156,6 +165,7 @@ fun AppUpdateDialog(
                             Row(
                                 modifier = Modifier.fillMaxWidth(),
                                 horizontalArrangement = Arrangement.SpaceBetween,
+                                verticalAlignment = Alignment.CenterVertically,
                             ) {
                                 val progressPercent = (state.progress * 100).toInt()
                                 Text(
@@ -167,8 +177,18 @@ fun AppUpdateDialog(
                                     style = MaterialTheme.typography.bodySmall,
                                     color = MaterialTheme.colorScheme.onSurfaceVariant,
                                 )
+                                if (currentAvailable != null && currentAvailable.sizeBytes > 0) {
+                                    val downloadedMb = (state.progress * currentAvailable.sizeBytes) / (1024 * 1024.0)
+                                    val totalMb = currentAvailable.sizeBytes / (1024 * 1024.0)
+                                    Text(
+                                        text = "%.1f / %.1f MB".format(downloadedMb, totalMb),
+                                        style = MaterialTheme.typography.labelSmall,
+                                        color = MaterialTheme.colorScheme.onSurfaceVariant,
+                                    )
                                 }
-                            Spacer(modifier = Modifier.height(6.dp))
+                            }
+                            Spacer(modifier = Modifier.height(8.dp))
+                            if (state.progress > 0f) {
                                 LinearProgressIndicator(
                                     progress = { state.progress },
                                     modifier =
@@ -177,6 +197,15 @@ fun AppUpdateDialog(
                                             .height(8.dp)
                                             .clip(RoundedCornerShape(4.dp)),
                                 )
+                            } else {
+                                LinearProgressIndicator(
+                                    modifier =
+                                        Modifier
+                                            .fillMaxWidth()
+                                            .height(8.dp)
+                                            .clip(RoundedCornerShape(4.dp)),
+                                )
+                            }
                             Spacer(modifier = Modifier.height(12.dp))
                             OutlinedButton(
                                 onClick = onCancelDownload,
@@ -188,11 +217,21 @@ fun AppUpdateDialog(
                     }
 
                     is AppUpdateState.Installing -> {
+                        Column(modifier = Modifier.fillMaxWidth()) {
                             Text(
                                 text = stringResource(R.string.settings_about_update_installing, tag),
                                 style = MaterialTheme.typography.bodyMedium,
                                 color = MaterialTheme.colorScheme.primary,
                             )
+                            Spacer(modifier = Modifier.height(8.dp))
+                            LinearProgressIndicator(
+                                modifier =
+                                    Modifier
+                                        .fillMaxWidth()
+                                        .height(8.dp)
+                                        .clip(RoundedCornerShape(4.dp)),
+                            )
+                        }
                     }
 
                     is AppUpdateState.NeedsUnknownSourcesPermission -> {

app/src/main/java/com/m57/hermescontrol/ui/settings/AppUpdateViewModel.kt

@@ -43,10 +43,14 @@ class AppUpdateViewModel(
     val state: StateFlow<AppUpdateState> = _state.asStateFlow()
 
     private var downloadJob: kotlinx.coroutines.Job? = null
+    private var lastAvailable: AppUpdateState.UpdateAvailable? = null
 
     init {
         val cached = AppUpdateCache.state.value
-        if (cached is AppUpdateState.UpdateAvailable || cached is AppUpdateState.UpToDate) {
+        if (cached is AppUpdateState.UpdateAvailable) {
+            lastAvailable = cached
+            _state.value = cached
+        } else if (cached is AppUpdateState.UpToDate) {
             _state.value = cached
         } else {
             checkForUpdate()
@@ -83,12 +87,13 @@ class AppUpdateViewModel(
                 }
             _state.value =
                 if (isNewerVersion(info.tagName, currentVersion)) {
-                    AppUpdateState.UpdateAvailable(
+                    AppUpdateState
+                        .UpdateAvailable(
                             latestTag = info.tagName,
                             apkUrl = apk.browserDownloadUrl,
                             sizeBytes = apk.size,
                             releaseNotes = info.body,
-                    )
+                        ).also { lastAvailable = it }
                 } else {
                     AppUpdateState.UpToDate(latestTag = info.tagName)
                 }
@@ -100,7 +105,12 @@ class AppUpdateViewModel(
 
     /** Download the release APK and launch the system installer. */
     fun startUpdate() {
-        val available = _state.value as? AppUpdateState.UpdateAvailable ?: return
+        val available =
+            (_state.value as? AppUpdateState.UpdateAvailable)
+                ?: lastAvailable
+                ?: (AppUpdateCache.state.value as? AppUpdateState.UpdateAvailable)
+                ?: return
+        lastAvailable = available
         if (!canRequestInstalls()) {
             _state.value = AppUpdateState.NeedsUnknownSourcesPermission
             return
@@ -129,7 +139,9 @@ class AppUpdateViewModel(
     fun cancelDownload() {
         downloadJob?.cancel()
         downloadJob = null
-        val available = AppUpdateCache.state.value as? AppUpdateState.UpdateAvailable
+        val available =
+            lastAvailable
+                ?: (AppUpdateCache.state.value as? AppUpdateState.UpdateAvailable)
         if (available != null) {
             _state.value = available
         } else {
@@ -139,7 +151,10 @@ class AppUpdateViewModel(
 
     /** Dismiss the current update tag so it stops nagging. */
     fun dismissCurrentUpdate() {
-        val tag = _state.value.releaseTag()
+        val tag =
+            _state.value.releaseTag()
+                ?: lastAvailable?.latestTag
+                ?: AppUpdateCache.state.value.releaseTag()
         if (tag != null) {
             AuthManager.setDismissedUpdateTag(tag)
         }
@@ -152,8 +167,9 @@ class AppUpdateViewModel(
         if (canRequestInstalls()) {
             val dest = File(getApplication<Application>().cacheDir, APK_FILE_NAME)
             val available =
-                _state.value as? AppUpdateState.UpdateAvailable
+                (_state.value as? AppUpdateState.UpdateAvailable)
-                    ?: AppUpdateCache.state.value as? AppUpdateState.UpdateAvailable
+                    ?: lastAvailable
+                    ?: (AppUpdateCache.state.value as? AppUpdateState.UpdateAvailable)
             if (dest.exists() && dest.length() > 0 && available != null) {
                 _state.value = AppUpdateState.Installing(available.latestTag)
                 launchInstaller(dest)

app/src/main/java/com/m57/hermescontrol/ui/settings/components/AboutSection.kt

@@ -178,10 +178,16 @@ private fun UpdateRow(
             }
 
             is AppUpdateState.Downloading -> {
+                if (state.progress > 0f) {
                     LinearProgressIndicator(
                         progress = { state.progress },
                         modifier = Modifier.fillMaxWidth().padding(top = 8.dp),
                     )
+                } else {
+                    LinearProgressIndicator(
+                        modifier = Modifier.fillMaxWidth().padding(top = 8.dp),
+                    )
+                }
             }
 
             is AppUpdateState.NeedsUnknownSourcesPermission -> {

app/src/test/java/com/m57/hermescontrol/ui/settings/AppUpdateViewModelTest.kt

@@ -333,4 +333,53 @@ class AppUpdateViewModelTest {
             assertTrue(AppUpdateCache.dismissed)
             assertFalse(AppUpdateCache.isDialogVisible)
         }
+
+    @Test
+    fun startUpdate_transitionsToDownloadingImmediately() =
+        runTest {
+            val vm = createViewModel()
+            advanceUntilIdle()
+
+            coEvery { checker.downloadApk(any(), any(), any()) } coAnswers {
+                kotlinx.coroutines.delay(5000)
+                true
+            }
+
+            vm.startUpdate()
+            // Immediately upon startUpdate call (before dispatcher advances coroutine time),
+            // state must be Downloading(0f) to give immediate visual feedback.
+            val state = vm.state.value
+            assertTrue("State must immediately be Downloading", state is AppUpdateState.Downloading)
+            assertEquals(0f, (state as AppUpdateState.Downloading).progress, 0.001f)
+        }
+
+    @Test
+    fun startUpdate_fromIdleAdoptsCachedAvailableAndStartsDownloading() =
+        runTest {
+            // Suppose VM is created when no check had run yet
+            every { AuthManager.getUpdateCheckDoneForVersion() } returns currentVersion
+            coEvery { checker.fetchLatestRelease() } returns null
+
+            val vm = createViewModel()
+            advanceUntilIdle()
+            assertEquals(AppUpdateState.Idle, vm.state.value)
+
+            // Simulate launch check finishing and posting to AppUpdateCache
+            val available =
+                AppUpdateState.UpdateAvailable(
+                    latestTag = "v1.23.0",
+                    apkUrl = "https://example.com/apk",
+                    sizeBytes = 5000L,
+                )
+            AppUpdateCache.update(available)
+
+            coEvery { checker.downloadApk(any(), any(), any()) } coAnswers {
+                kotlinx.coroutines.delay(5000)
+                true
+            }
+
+            vm.startUpdate()
+            val state = vm.state.value
+            assertTrue("Must transition to Downloading using cached update", state is AppUpdateState.Downloading)
+        }
 }