detail: do not cache viewholder pos for highlight

Fix an issue with highlighting in the detail UIs taht stemmed from the
ViewHolder position being cached.

Resorting could have changed the ViewHolder position, so caching it
will result in ViewHolders being incorrectly updated.

app/src/main/java/org/oxycblt/auxio/detail/recycler/AlbumDetailAdapter.kt

@@ -45,7 +45,6 @@ import org.oxycblt.auxio.util.textSafe
 class AlbumDetailAdapter(listener: Listener) :
     DetailAdapter<AlbumDetailAdapter.Listener>(listener, DIFFER) {
     private var currentSong: Song? = null
-    private var currentSongPos: Int? = null
 
     override fun getCreatorFromItem(item: Item) =
         super.getCreatorFromItem(item)
@@ -81,14 +80,13 @@ class AlbumDetailAdapter(listener: Listener) :
         }
     }
 
-    override fun shouldHighlightViewHolder(item: Item) = item.id == currentSong?.id
+    override fun shouldHighlightViewHolder(item: Item) = item is Song && item.id == currentSong?.id
 
     /** Update the [song] that this adapter should highlight */
     fun highlightSong(song: Song?) {
         if (song == currentSong) return
+        highlightImpl(currentSong, song)
         currentSong = song
-        currentSongPos?.let { pos -> notifyItemChanged(pos, PAYLOAD_HIGHLIGHT_CHANGED) }
-        currentSongPos = highlightItem(song)
     }
 
     companion object {

app/src/main/java/org/oxycblt/auxio/detail/recycler/ArtistDetailAdapter.kt

@@ -45,10 +45,7 @@ import org.oxycblt.auxio.util.textSafe
 class ArtistDetailAdapter(listener: Listener) :
     DetailAdapter<DetailAdapter.Listener>(listener, DIFFER) {
     private var currentAlbum: Album? = null
-    private var currentAlbumPos: Int? = null
-
     private var currentSong: Song? = null
-    private var currentHighlightedSongPos: Int? = null
 
     override fun getCreatorFromItem(item: Item) =
         super.getCreatorFromItem(item)
@@ -92,17 +89,15 @@ class ArtistDetailAdapter(listener: Listener) :
     /** Update the current [album] that this adapter should highlight */
     fun highlightAlbum(album: Album?) {
         if (album == currentAlbum) return
+        highlightImpl(currentAlbum, album)
         currentAlbum = album
-        currentAlbumPos?.let { pos -> notifyItemChanged(pos, PAYLOAD_HIGHLIGHT_CHANGED) }
-        currentAlbumPos = highlightItem(album)
     }
 
     /** Update the [song] that this adapter should highlight */
     fun highlightSong(song: Song?) {
         if (song == currentSong) return
+        highlightImpl(currentSong, song)
         currentSong = song
-        currentHighlightedSongPos?.let { notifyItemChanged(it, PAYLOAD_HIGHLIGHT_CHANGED) }
-        currentHighlightedSongPos = highlightItem(song)
     }
 
     companion object {

app/src/main/java/org/oxycblt/auxio/detail/recycler/DetailAdapter.kt

@@ -35,6 +35,7 @@ import org.oxycblt.auxio.ui.NewHeaderViewHolder
 import org.oxycblt.auxio.ui.SimpleItemCallback
 import org.oxycblt.auxio.util.context
 import org.oxycblt.auxio.util.inflater
+import org.oxycblt.auxio.util.logW
 import org.oxycblt.auxio.util.textSafe
 
 abstract class DetailAdapter<L : DetailAdapter.Listener>(
@@ -43,16 +44,26 @@ abstract class DetailAdapter<L : DetailAdapter.Listener>(
 ) : MultiAdapter<L>(listener) {
     abstract fun shouldHighlightViewHolder(item: Item): Boolean
 
-    protected inline fun <reified T : Item> highlightItem(newItem: T?): Int? {
+    protected inline fun <reified T : Item> highlightImpl(oldItem: T?, newItem: T?) {
-        if (newItem == null) {
+        if (oldItem != null) {
-            return null
+            val pos = data.currentList.indexOfFirst { item -> item.id == oldItem.id && item is T }
+
+            if (pos > -1) {
+                notifyItemChanged(pos, PAYLOAD_HIGHLIGHT_CHANGED)
+            } else {
+                logW("oldItem was not in adapter data")
+            }
         }
 
-        // Use existing data instead of having to re-sort it.
+        if (newItem != null) {
-        // We also have to account for the album count when searching for the ViewHolder.
+            val pos = data.currentList.indexOfFirst { item -> item is T && item.id == newItem.id }
-        val pos = data.currentList.indexOfFirst { item -> item.id == newItem.id && item is T }
+
+            if (pos > -1) {
                 notifyItemChanged(pos, PAYLOAD_HIGHLIGHT_CHANGED)
-        return pos
+            } else {
+                logW("newItem was not in adapter data")
+            }
+        }
     }
 
     @Suppress("LeakingThis") override val data = AsyncBackingData(this, diffCallback)
@@ -90,7 +101,7 @@ abstract class DetailAdapter<L : DetailAdapter.Listener>(
     companion object {
         // This payload value serves two purposes:
         // 1. It disables animations from notifyItemChanged, which looks bad when highlighting
-        // values.
+        // ViewHolders.
         // 2. It instructs adapters to avoid re-binding information, and instead simply
         // change the highlight state.
         val PAYLOAD_HIGHLIGHT_CHANGED = Any()

app/src/main/java/org/oxycblt/auxio/detail/recycler/GenreDetailAdapter.kt

@@ -43,7 +43,6 @@ import org.oxycblt.auxio.util.textSafe
 class GenreDetailAdapter(listener: Listener) :
     DetailAdapter<DetailAdapter.Listener>(listener, DIFFER) {
     private var currentSong: Song? = null
-    private var currentSongPos: Int? = null
 
     override fun getCreatorFromItem(item: Item) =
         super.getCreatorFromItem(item)
@@ -77,14 +76,13 @@ class GenreDetailAdapter(listener: Listener) :
         }
     }
 
-    override fun shouldHighlightViewHolder(item: Item) = item.id == currentSong?.id
+    override fun shouldHighlightViewHolder(item: Item) = item is Song && item.id == currentSong?.id
 
     /** Update the [song] that this adapter should highlight */
     fun highlightSong(song: Song?) {
         if (song == currentSong) return
+        highlightImpl(currentSong, song)
         currentSong = song
-        currentSongPos?.let { pos -> notifyItemChanged(pos, PAYLOAD_HIGHLIGHT_CHANGED) }
-        currentSongPos = highlightItem(song)
     }
 
     companion object {

app/src/main/java/org/oxycblt/auxio/image/BitmapProvider.kt

@@ -25,7 +25,6 @@ import coil.request.Disposable
 import coil.request.ImageRequest
 import coil.size.Size
 import org.oxycblt.auxio.music.Song
-import org.oxycblt.auxio.util.logD
 
 /**
  * A utility to provide bitmaps in a manner less prone to race conditions.