Perf audit batch 1 (app-side): preserve res-cap on autoplay + detail LazyColumn — vc=78

From the multi-agent perf audit (adversarially verified), the two app-side wins:

- 1.1 Preserve the max-resolution cap on autoplay-next. The enter-video
  trackSelectionParameters reset built from a blank default, silently
  dropping the data-saver ceiling every URL change so autoplay streamed
  uncapped. Now: re-enable the video track via buildUpon + reassert
  applyMaxResolutionCap().
- 2.1 VideoDetailBody verticalScroll Column -> LazyColumn. Related +
  more-from-channel rows recycle and defer each AsyncImage decode + the
  two ThumbnailProgress flow collectors until scrolled into view (was ~40
  decodes + ~80 collectors eager on every open). Namespaced item keys
  (rel:/mfc:) so a url in both lists doesn't crash the list; kept take(20);
  dialogs hoisted out of the lazy content.

buildSrc/src/main/kotlin/ProjectConfig.kt

@@ -9,6 +9,17 @@ const val STRAW_SDK_TARGET = 35
 
 // Sulkta fork — Straw
 //
+// vc=78 / 0.1.0-CL — perf-audit batch 1 (app-side):
+//   * Autoplay-next no longer drops the user's max-resolution cap. The
+//     enter-video track-selection reset built params from scratch, wiping
+//     the data-saver ceiling on every URL change; now it re-enables the
+//     video track surgically + re-asserts applyMaxResolutionCap().
+//   * VideoDetail body is now a LazyColumn, not a verticalScroll Column.
+//     The related + more-from-channel lists recycle and defer each row's
+//     image decode + its two progress-overlay flow collectors until
+//     scrolled into view (was ~40 decodes + ~80 collectors mounted eagerly
+//     on every video open). Namespaced item keys; dialogs hoisted out.
+//
 // vc=77 / 0.1.0-CK — morph perf: static poster during collapse/morph:
 //   * The minibar + the whole collapse/expand morph now render the video's
 //     static poster, not the live TextureView. Scaling a live-playing
@@ -89,6 +100,6 @@ const val STRAW_SDK_TARGET = 35
 // vc=19 / 0.1.0-AE — rust pipeline cutover. Extraction via
 // strawcore-core (Sulkta-OSS/strawcore) via the UniFFI wrapper; no
 // NewPipeExtractor in the runtime path.
-const val STRAW_VERSION_CODE = 77
+const val STRAW_VERSION_CODE = 78
-const val STRAW_VERSION_NAME = "0.1.0-CK"
+const val STRAW_VERSION_NAME = "0.1.0-CL"
 const val STRAW_APPLICATION_ID = "com.sulkta.straw"

strawApp/src/main/kotlin/com/sulkta/straw/feature/detail/VideoDetailBody.kt

@@ -48,10 +48,11 @@ import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.size
 import androidx.compose.foundation.layout.width
 import androidx.compose.foundation.layout.windowInsetsBottomHeight
+import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.foundation.lazy.items
 import androidx.compose.foundation.rememberScrollState
 import androidx.compose.foundation.shape.CircleShape
 import androidx.compose.foundation.shape.RoundedCornerShape
-import androidx.compose.foundation.verticalScroll
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.filled.Download
 import androidx.compose.material.icons.filled.ExpandLess
@@ -139,26 +140,30 @@ fun VideoDetailBody(
         VideoActionsSheet(target = t, onDismiss = { actionTarget = null })
     }
 
-    Column(
+    // LazyColumn (was a verticalScroll Column): the related/more-from rows
-        modifier = Modifier
+    // now recycle and defer their image decode + 2 progress-overlay flow
-            .fillMaxWidth()
+    // collectors until scrolled into view, instead of mounting ~40 rows
-            .verticalScroll(rememberScrollState()),
+    // (~40 decodes + ~80 collectors) eagerly on every video open.
-    ) {
+    LazyColumn(modifier = Modifier.fillMaxWidth()) {
-        Spacer(modifier = Modifier.height(topPadding))
+        item { Spacer(modifier = Modifier.height(topPadding)) }
 
         when {
-            state.loading -> Box(
+            state.loading -> item {
-                modifier = Modifier
+                Box(
-                    .fillMaxWidth()
+                    modifier = Modifier
-                    .padding(top = 64.dp),
+                        .fillMaxWidth()
-                contentAlignment = Alignment.Center,
+                        .padding(top = 64.dp),
-            ) { CircularProgressIndicator() }
+                    contentAlignment = Alignment.Center,
+                ) { CircularProgressIndicator() }
+            }
 
-            state.error != null -> Text(
+            state.error != null -> item {
-                "error: ${state.error}",
+                Text(
-                color = MaterialTheme.colorScheme.error,
+                    "error: ${state.error}",
-                modifier = Modifier.padding(16.dp),
+                    color = MaterialTheme.colorScheme.error,
-            )
+                    modifier = Modifier.padding(16.dp),
+                )
+            }
 
             else -> {
                 val d = state.detail
@@ -166,11 +171,16 @@ fun VideoDetailBody(
                 // detail for one frame before vm.load(B) resets. Gate on
                 // loadedUrl so we never render A's metadata under B.
                 if (d == null || state.loadedUrl != streamUrl) {
-                    Box(
+                    item {
-                        modifier = Modifier.fillMaxWidth().padding(top = 64.dp),
+                        Box(
-                        contentAlignment = Alignment.Center,
+                            modifier = Modifier.fillMaxWidth().padding(top = 64.dp),
-                    ) { CircularProgressIndicator() }
+                            contentAlignment = Alignment.Center,
+                        ) { CircularProgressIndicator() }
+                    }
                 } else {
+                    // Header (title/channel/stats/pills/Details) — one item;
+                    // fixed content, doesn't benefit from row recycling.
+                    item {
                     Column(modifier = Modifier.padding(horizontal = 16.dp, vertical = 12.dp)) {
                         Text(
                             text = d.title,
@@ -410,15 +420,30 @@ fun VideoDetailBody(
                             )
                         }
 
-                        if (d.related.isNotEmpty()) {
+                    }
-                            Spacer(modifier = Modifier.height(24.dp))
+                    }
-                            Text(
+
-                                "Recommended",
+                    if (d.related.isNotEmpty()) {
-                                style = MaterialTheme.typography.titleSmall,
+                        item {
-                                fontWeight = FontWeight.SemiBold,
+                            Column(modifier = Modifier.padding(horizontal = 16.dp)) {
-                            )
+                                Spacer(modifier = Modifier.height(24.dp))
-                            Spacer(modifier = Modifier.height(8.dp))
+                                Text(
-                            d.related.take(20).forEach { rel ->
+                                    "Recommended",
+                                    style = MaterialTheme.typography.titleSmall,
+                                    fontWeight = FontWeight.SemiBold,
+                                )
+                                Spacer(modifier = Modifier.height(8.dp))
+                            }
+                        }
+                        // Namespaced key (rel: / mfc:) — the same video URL can
+                        // appear in BOTH lists; a bare url key crashes the
+                        // LazyColumn with "Key already used".
+                        items(
+                            items = d.related.take(20),
+                            key = { "rel:" + it.url },
+                            contentType = { "related" },
+                        ) { rel ->
+                            Column(modifier = Modifier.padding(horizontal = 16.dp)) {
                                 RelatedRow(
                                     item = rel,
                                     onClick = { onOpenVideo(rel.url, rel.title) },
@@ -434,102 +459,117 @@ fun VideoDetailBody(
                                 HorizontalDivider()
                             }
                         }
+                    }
 
-                        if (d.moreFromChannel.isNotEmpty()) {
+                    if (d.moreFromChannel.isNotEmpty()) {
-                            Spacer(modifier = Modifier.height(24.dp))
+                        item {
-                            Text(
+                            Column(modifier = Modifier.padding(horizontal = 16.dp)) {
-                                if (d.uploader.isBlank()) "More from this channel"
+                                Spacer(modifier = Modifier.height(24.dp))
-                                else "More from ${d.uploader}",
+                                Text(
-                                style = MaterialTheme.typography.titleSmall,
+                                    if (d.uploader.isBlank()) "More from this channel"
-                                fontWeight = FontWeight.SemiBold,
+                                    else "More from ${d.uploader}",
-                            )
+                                    style = MaterialTheme.typography.titleSmall,
-                            Spacer(modifier = Modifier.height(8.dp))
+                                    fontWeight = FontWeight.SemiBold,
-                            d.moreFromChannel.take(20).forEach { item ->
+                                )
+                                Spacer(modifier = Modifier.height(8.dp))
+                            }
+                        }
+                        items(
+                            items = d.moreFromChannel.take(20),
+                            key = { "mfc:" + it.url },
+                            contentType = { "related" },
+                        ) { mfc ->
+                            Column(modifier = Modifier.padding(horizontal = 16.dp)) {
                                 RelatedRow(
-                                    item = item,
+                                    item = mfc,
-                                    onClick = { onOpenVideo(item.url, item.title) },
+                                    onClick = { onOpenVideo(mfc.url, mfc.title) },
                                     onLongClick = {
                                         actionTarget = VideoActionTarget(
-                                            streamUrl = item.url,
+                                            streamUrl = mfc.url,
-                                            title = item.title,
+                                            title = mfc.title,
-                                            uploader = item.uploader,
+                                            uploader = mfc.uploader,
-                                            thumbnail = item.thumbnail,
+                                            thumbnail = mfc.thumbnail,
                                         )
                                     },
                                 )
                                 HorizontalDivider()
                             }
                         }
-
-                        if (showSaveToPlaylistDialog) {
-                            SaveToPlaylistDialog(
-                                item = PlaylistItem(
-                                    streamUrl = streamUrl,
-                                    title = d.title,
-                                    thumbnail = d.thumbnail,
-                                    uploader = d.uploader,
-                                ),
-                                onDismiss = { showSaveToPlaylistDialog = false },
-                            )
-                        }
-
-                        if (showDownloadDialog) {
-                            val info = state.streamInfo
-                            AlertDialog(
-                                onDismissRequest = { showDownloadDialog = false },
-                                title = { Text("Download") },
-                                text = {
-                                    Column {
-                                        Text("Pick a format:", style = MaterialTheme.typography.bodyMedium)
-                                        Spacer(modifier = Modifier.height(8.dp))
-                                        Text(
-                                            "Saves to Android/data/.../files/Movies/. Visible in any file manager.",
-                                            style = MaterialTheme.typography.bodySmall,
-                                            color = MaterialTheme.colorScheme.onSurfaceVariant,
-                                        )
-                                    }
-                                },
-                                confirmButton = {
-                                    Row(horizontalArrangement = Arrangement.spacedBy(8.dp)) {
-                                        Button(onClick = {
-                                            val audio = info?.audioOnly?.maxByOrNull { it.bitrate }?.url
-                                            if (audio != null) {
-                                                val id = Downloader.enqueue(context, audio, d.title, DownloadKind.Audio)
-                                                val msg = if (id > 0) "audio queued" else "download refused (bad URL)"
-                                                Toast.makeText(context, msg, Toast.LENGTH_SHORT).show()
-                                            } else {
-                                                Toast.makeText(context, "no audio stream", Toast.LENGTH_SHORT).show()
-                                            }
-                                            showDownloadDialog = false
-                                        }) { Text("Audio") }
-                                        Button(onClick = {
-                                            val video = info?.combined?.maxByOrNull { it.bitrate }?.url
-                                                ?: info?.videoOnly?.maxByOrNull { it.bitrate }?.url
-                                            if (video != null) {
-                                                val id = Downloader.enqueue(context, video, d.title, DownloadKind.Video)
-                                                val msg = if (id > 0) "video queued" else "download refused (bad URL)"
-                                                Toast.makeText(context, msg, Toast.LENGTH_SHORT).show()
-                                            } else {
-                                                Toast.makeText(context, "no video stream", Toast.LENGTH_SHORT).show()
-                                            }
-                                            showDownloadDialog = false
-                                        }) { Text("Video") }
-                                    }
-                                },
-                                dismissButton = {
-                                    TextButton(onClick = { showDownloadDialog = false }) {
-                                        Text("Cancel")
-                                    }
-                                },
-                            )
-                        }
                     }
                 }
             }
         }
         // Clear the system nav bar so the last related row isn't tucked
         // under the gesture pill.
-        Spacer(modifier = Modifier.windowInsetsBottomHeight(WindowInsets.navigationBars))
+        item {
+            Spacer(modifier = Modifier.windowInsetsBottomHeight(WindowInsets.navigationBars))
+        }
+    }
+
+    // Dialogs live at the composable level (not inside a recyclable lazy
+    // item): state-driven, rendered once. They need the loaded detail.
+    state.detail?.let { d ->
+        if (showSaveToPlaylistDialog) {
+            SaveToPlaylistDialog(
+                item = PlaylistItem(
+                    streamUrl = streamUrl,
+                    title = d.title,
+                    thumbnail = d.thumbnail,
+                    uploader = d.uploader,
+                ),
+                onDismiss = { showSaveToPlaylistDialog = false },
+            )
+        }
+        if (showDownloadDialog) {
+            val info = state.streamInfo
+            AlertDialog(
+                onDismissRequest = { showDownloadDialog = false },
+                title = { Text("Download") },
+                text = {
+                    Column {
+                        Text("Pick a format:", style = MaterialTheme.typography.bodyMedium)
+                        Spacer(modifier = Modifier.height(8.dp))
+                        Text(
+                            "Saves to Android/data/.../files/Movies/. Visible in any file manager.",
+                            style = MaterialTheme.typography.bodySmall,
+                            color = MaterialTheme.colorScheme.onSurfaceVariant,
+                        )
+                    }
+                },
+                confirmButton = {
+                    Row(horizontalArrangement = Arrangement.spacedBy(8.dp)) {
+                        Button(onClick = {
+                            val audio = info?.audioOnly?.maxByOrNull { it.bitrate }?.url
+                            if (audio != null) {
+                                val id = Downloader.enqueue(context, audio, d.title, DownloadKind.Audio)
+                                val msg = if (id > 0) "audio queued" else "download refused (bad URL)"
+                                Toast.makeText(context, msg, Toast.LENGTH_SHORT).show()
+                            } else {
+                                Toast.makeText(context, "no audio stream", Toast.LENGTH_SHORT).show()
+                            }
+                            showDownloadDialog = false
+                        }) { Text("Audio") }
+                        Button(onClick = {
+                            val video = info?.combined?.maxByOrNull { it.bitrate }?.url
+                                ?: info?.videoOnly?.maxByOrNull { it.bitrate }?.url
+                            if (video != null) {
+                                val id = Downloader.enqueue(context, video, d.title, DownloadKind.Video)
+                                val msg = if (id > 0) "video queued" else "download refused (bad URL)"
+                                Toast.makeText(context, msg, Toast.LENGTH_SHORT).show()
+                            } else {
+                                Toast.makeText(context, "no video stream", Toast.LENGTH_SHORT).show()
+                            }
+                            showDownloadDialog = false
+                        }) { Text("Video") }
+                    }
+                },
+                dismissButton = {
+                    TextButton(onClick = { showDownloadDialog = false }) {
+                        Text("Cancel")
+                    }
+                },
+            )
+        }
     }
 }
 

strawApp/src/main/kotlin/com/sulkta/straw/feature/player/ExpandablePlayer.kt

@@ -161,13 +161,18 @@ fun ExpandablePlayer(
         }
     }
 
-    // Entering a video means "watch the video": wipe any audio-only track
+    // Entering a video means "watch the video": re-enable the video track
-    // override left by a prior Background/Audio action so DASH picks the
+    // (clearing any audio-only override left by a prior Background/Audio
-    // best video track again.
+    // action) — but PRESERVE the user's max-resolution cap. Building params
+    // from scratch (the old code) silently dropped the data-saver ceiling, so
+    // every autoplay-next streamed uncapped resolution until the next
+    // setPlayingFrom re-applied it. Surgical buildUpon + re-assert the cap.
     LaunchedEffect(controller, cur.streamUrl) {
         controller?.let {
-            it.trackSelectionParameters =
+            it.trackSelectionParameters = it.trackSelectionParameters.buildUpon()
-                androidx.media3.common.TrackSelectionParameters.Builder(context).build()
+                .setTrackTypeDisabled(androidx.media3.common.C.TRACK_TYPE_VIDEO, false)
+                .build()
+            it.applyMaxResolutionCap()
         }
     }