refactor: slim IndexingProgress to a producer-supplied [0,1] progress

perFileProgress was never populated and its progress branch was
unreachable; currentFile, currentIndex, currentFileProgress and label
were write-only (no consumer read them); progressPercent had no
callers; the -1f aggregate sentinel is gone along with the fallback
branches that only fired when the tracker was absent.

app/src/main/java/com/example/research/core/domain/model/IndexingProgress.kt

@@ -1,42 +1,13 @@
 package com.example.research.core.domain.model
-import kotlin.math.roundToInt
 
 /**
  * Snapshot of an ongoing indexing operation.
  *
- * [progress] is the authoritative [0f, 1f] completion value and is O(1) to
+ * [progress] is the authoritative [0f, 1f] completion value: the repository
- * compute: the repository's internal `ProgressTracker` maintains a running
+ * aggregates a file-size-weighted sum across files incrementally while
- * sum across files incrementally and stores it in [aggregateSum], avoiding
+ * indexing, so reading it is O(1).
- * an O(n) walk over [perFileProgress] on every read.
- * [perFileProgress] is kept for diagnostics; callers should prefer
- * [progress] / [progressPercent].
  */
 data class IndexingProgress(
-    val currentFile: String = "",
-    val currentIndex: Int = 0,
-    val totalFiles: Int = 0,
     val isIndexing: Boolean = false,
-    val currentFileProgress: Float = 0f,
+    val progress: Float = 0f,
-    val label: String = "",
+)
-    val perFileProgress: Map<String, Float> = emptyMap(),
-    /** Pre-aggregated sum in [0f, totalFiles] supplied by the producer; -1f = unknown. */
-    val aggregateSum: Float = -1f,
-) {
-    val progress: Float
-        get() = if (totalFiles > 0) {
-            when {
-                aggregateSum >= 0f -> (aggregateSum / totalFiles).coerceIn(0f, 1f)
-                perFileProgress.isNotEmpty() -> {
-                    val totalProgress = perFileProgress.values.sum()
-                    (totalProgress / totalFiles).coerceIn(0f, 1f)
-                }
-                else -> {
-                    val completedFiles = (currentIndex - 1).coerceAtLeast(0)
-                    ((completedFiles + currentFileProgress) / totalFiles).coerceIn(0f, 1f)
-                }
-            }
-        } else 0f
-
-    val progressPercent: Int
-        get() = (progress * 100).roundToInt().coerceIn(0, 100)
-}

app/src/main/java/com/example/research/data/repository/LocalDictionaryRepository.kt

@@ -70,13 +70,9 @@ private class ProgressTracker(files: List<LocalDictionaryRepository.DiscoveredFi
         aggregateWeightedMicros.addAndGet(newMicros - prevMicros)
     }
 
-    /**
+    fun progress(): Float {
-     * Current weighted sum mapped back to [0f, totalFiles] so the existing
-     * IndexingProgress model can keep deriving progress as aggregate/total.
-     */
-    fun aggregateSum(): Float {
         val weightedProgress = aggregateWeightedMicros.get().toDouble() / (totalWeight.toDouble() * 1_000_000.0)
-        return (weightedProgress.coerceIn(0.0, 1.0) * totalFiles).toFloat()
+        return weightedProgress.coerceIn(0.0, 1.0).toFloat()
     }
 
     fun reset() {
@@ -194,10 +190,7 @@ class LocalDictionaryRepository(
                 mutableIndexingProgress.emit(
                     IndexingProgress(
                         isIndexing = true,
-                        currentFile = context.getString(R.string.indexing_label),
+                        progress = progressTracker?.progress() ?: 0f,
-                        totalFiles = filesToScan.size,
-                        currentIndex = filesToScan.size - filesToIndex.size,
-                        aggregateSum = progressTracker?.aggregateSum() ?: -1f,
                     )
                 )
 
@@ -205,44 +198,32 @@ class LocalDictionaryRepository(
                 val lastProgressEmitMs = AtomicLong(0L)
 
                 supervisorScope {
-                    filesToIndex.mapIndexed { index, file ->
+                    filesToIndex.map { file ->
                         async {
                             indexingSemaphore.withPermit {
                                 coroutineContext.ensureActive()
                                 yield()
 
-                                val res = indexDictionary(file) { _, op, prog ->
+                                val res = indexDictionary(file) { _, _, prog ->
                                     if (prog >= 0f) {
                                         progressTracker?.updateFileProgress(file.name, prog)
                                     }
 
-                                    val tracker = progressTracker
+                                    val progress = progressTracker?.progress() ?: 0f
-                                    val aggregate = tracker?.aggregateSum() ?: -1f
+                                    val newPercent = (progress * 100f).toInt().coerceIn(0, 100)
-                                    val newPercent = if (filesToScan.isNotEmpty() && aggregate >= 0f) {
-                                        ((aggregate / filesToScan.size) * 100f).toInt().coerceIn(0, 100)
-                                    } else -1
 
-                                    val currentIdx = filesToScan.size - filesToIndex.size + index + 1
-                                    val previous = mutableIndexingProgress.value
                                     val now = SystemClock.elapsedRealtime()
-                                    val percentChanged = newPercent >= 0 && newPercent != lastEmittedPercent.get()
+                                    val percentChanged = newPercent != lastEmittedPercent.get()
-                                    val fileChanged = previous.currentFile != file.name
                                     val completed = newPercent >= 100 || prog >= 1f
                                     val intervalElapsed =
                                         now - lastProgressEmitMs.get() >= MIN_PROGRESS_EMIT_INTERVAL_MS
-                                    val shouldEmit = fileChanged || completed || (percentChanged && intervalElapsed)
+                                    val shouldEmit = completed || (percentChanged && intervalElapsed)
 
                                     if (shouldEmit) {
-                                        if (newPercent >= 0) lastEmittedPercent.set(newPercent)
+                                        lastEmittedPercent.set(newPercent)
                                         lastProgressEmitMs.set(now)
                                         mutableIndexingProgress.update { p ->
-                                            p.copy(
+                                            p.copy(progress = progress)
-                                                currentFile = file.name,
-                                                currentIndex = currentIdx,
-                                                currentFileProgress = prog,
-                                                label = op.ifEmpty { p.label },
-                                                aggregateSum = aggregate,
-                                            )
                                         }
                                     }
                                 }