fix(settings): keep the update badge across PROCESS_TEXT relaunches

Persist NeedsUpdate with its source ids and restore today's persisted
status — UpToDate and NeedsUpdate alike — through one shared helper used
by both startup paths, falling back to a fresh evaluation when the
persisted status can no longer be trusted (stale date, removed sources,
or the update already installed).

app/src/main/java/com/example/research/ui/settings/SettingsViewModel.kt

@@ -37,6 +37,16 @@ import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
 import java.util.concurrent.ConcurrentHashMap
 
+private const val STATUS_UP_TO_DATE = "UpToDate"
+private const val STATUS_NEEDS_UPDATE = "NeedsUpdate"
+private const val STATUS_EMPTY = "Empty"
+
+private data class PersistedDictionaryStatus(
+    val name: String,
+    val date: String,
+    val sourceIds: Set<String>,
+)
+
 private data class DictionaryStateInputs(
     val theme: AppTheme,
     val dictionarySources: List<DictionarySource>,
@@ -115,14 +125,18 @@ class SettingsViewModel(
     private fun persistDictionaryStatus() {
         viewModelScope.launch {
             dictionaryStatus.collect { status ->
-                val persistedName = when (status) {
-                    DictionaryStatus.UpToDate -> "UpToDate"
-                    is DictionaryStatus.NeedsUpdate -> "NeedsUpdate"
-                    DictionaryStatus.Empty -> "Empty"
+                val persisted = when (status) {
+                    DictionaryStatus.UpToDate ->
+                        "$STATUS_UP_TO_DATE|${DateUtils.getCurrentDateString()}"
+                    is DictionaryStatus.NeedsUpdate ->
+                        "$STATUS_NEEDS_UPDATE|${DateUtils.getCurrentDateString()}|" +
+                            status.sourceIds.joinToString(",")
+                    DictionaryStatus.Empty ->
+                        "$STATUS_EMPTY|${DateUtils.getCurrentDateString()}"
                     else -> null
                 }
-                if (persistedName != null) {
-                    preferencesManager.saveDictionaryStatus("$persistedName|${DateUtils.getCurrentDateString()}")
+                if (persisted != null) {
+                    preferencesManager.saveDictionaryStatus(persisted)
                 }
             }
         }
@@ -283,7 +297,7 @@ class SettingsViewModel(
                 scanCompleted = if (localDictionaryRepository.dictionaries.value.isEmpty()) {
                     scanDirectoryInternal(preferencesManager.dictionaryPath) is OperationResult.Success
                 } else {
-                    dictionaryStatus.value = DictionaryStatus.UpToDate
+                    restoreOrEvaluateDictionaryStatus()
                     false
                 }
             } catch (e: Exception) {
@@ -551,6 +565,71 @@ class SettingsViewModel(
     ): List<DictionarySource> =
         DictionarySourceFileMatcher.installedSources(sources, dictionaries)
 
+    private suspend fun restoreOrEvaluateDictionaryStatus() {
+        val restored = restorePersistedDictionaryStatus()
+        if (restored != null) {
+            dictionaryStatus.value = restored
+            return
+        }
+        dictionaryStatus.value = DictionaryStatus.Checking
+        dictionaryStatus.value = withContext(Dispatchers.IO) { evaluateDictionaryStatus() }
+    }
+
+    private suspend fun restorePersistedDictionaryStatus(): DictionaryStatus? {
+        val persisted = readPersistedDictionaryStatus() ?: return null
+        if (persisted.date != DateUtils.getCurrentDateString()) return null
+        return when (persisted.name) {
+            STATUS_UP_TO_DATE ->
+                if (withContext(Dispatchers.IO) { installedDictionariesAreCurrent() }) {
+                    DictionaryStatus.UpToDate
+                } else {
+                    null
+                }
+            STATUS_NEEDS_UPDATE -> {
+                val updatableIds = withContext(Dispatchers.IO) { sourcesMissingTodaysFile() }
+                val restorableIds = persisted.sourceIds intersect updatableIds
+                if (restorableIds.isNotEmpty()) DictionaryStatus.NeedsUpdate(restorableIds) else null
+            }
+            else -> null
+        }
+    }
+
+    private suspend fun readPersistedDictionaryStatus(): PersistedDictionaryStatus? {
+        val raw = preferencesManager.dictionaryStatus() ?: return null
+        val parts = raw.split('|')
+        if (parts.isEmpty() || parts.first().isEmpty()) return null
+        return PersistedDictionaryStatus(
+            name = parts.first(),
+            date = parts.getOrElse(1) { "" },
+            sourceIds = parts.getOrElse(2) { "" }
+                .split(',')
+                .map(String::trim)
+                .filter(String::isNotEmpty)
+                .toSet(),
+        )
+    }
+
+    private suspend fun sourcesMissingTodaysFile(): Set<String> {
+        val sources = preferencesManager.dictionarySources.first()
+        val dictionaries = localDictionaryRepository.dictionaries.first()
+        val datedEnabledSources = installedEnabledSources(sources, dictionaries)
+            .filter { DictionarySource.hasDatePlaceholder(it.urlTemplate) }
+        if (datedEnabledSources.isEmpty()) return emptySet()
+        val fileNames = localDictionaryRepository.listDictionaryPayloadFileNames(
+            preferencesManager.dictionaryPath
+        ) ?: return emptySet()
+        val today = DateUtils.getCurrentDateString()
+        return datedEnabledSources
+            .filterNot { source -> fileNames.any { it.startsWith(fileBaseNameFor(source, today)) } }
+            .mapTo(mutableSetOf(), DictionarySource::id)
+    }
+
+    private fun fileBaseNameFor(source: DictionarySource, date: String): String =
+        DictionarySource.extractFileName(source.urlTemplate, date)
+            .removeSuffix(".gz")
+            .removeSuffix(".dsl")
+            .removeSuffix(".dz")
+
     private suspend fun installedDictionariesAreCurrent(): Boolean {
         val sources = preferencesManager.dictionarySources.first()
         val dictionaries = localDictionaryRepository.dictionaries.first()
@@ -562,11 +641,7 @@ class SettingsViewModel(
         ) ?: return true
         val today = DateUtils.getCurrentDateString()
         return datedEnabledSources.all { source ->
-            val baseName = DictionarySource.extractFileName(source.urlTemplate, today)
-                .removeSuffix(".gz")
-                .removeSuffix(".dsl")
-                .removeSuffix(".dz")
-            fileNames.any { it.startsWith(baseName) }
+            fileNames.any { it.startsWith(fileBaseNameFor(source, today)) }
         }
     }
 
@@ -622,20 +697,7 @@ class SettingsViewModel(
                     dictionaryStatus.value = DictionaryStatus.UpToDate
                     isDownloadInProgress = false
                 } else {
-                    val savedStatus = preferencesManager.dictionaryStatus()
-                    val savedStatusName = savedStatus?.substringBefore('|')
-                    val savedStatusDate = savedStatus?.substringAfter('|', "")
-                    val restoredStatus = if (savedStatusName == "UpToDate") DictionaryStatus.UpToDate else null
-                    if (restoredStatus != null &&
-                        savedStatusDate == DateUtils.getCurrentDateString() &&
-                        withContext(Dispatchers.IO) { installedDictionariesAreCurrent() }
-                    ) {
-                        dictionaryStatus.value = restoredStatus
-                    } else {
-                        dictionaryStatus.value = DictionaryStatus.Checking
-                        val status = withContext(Dispatchers.IO) { evaluateDictionaryStatus() }
-                        dictionaryStatus.value = status
-                    }
+                    restoreOrEvaluateDictionaryStatus()
                 }
 
                 if (result.data > 0) {