Optimize quality cover loading

Make the loading process for higher-quality covers far more efficent and elegant compared to the previous method.

app/src/main/java/org/oxycblt/auxio/coil/QualityCoverFetcher.kt

@@ -1,25 +1,28 @@
 package org.oxycblt.auxio.coil
 
 import android.content.Context
-import android.graphics.BitmapFactory
 import android.media.MediaMetadataRetriever
-import androidx.core.graphics.drawable.toDrawable
+import android.net.Uri
 import coil.bitmap.BitmapPool
 import coil.decode.DataSource
 import coil.decode.Options
-import coil.fetch.DrawableResult
 import coil.fetch.FetchResult
 import coil.fetch.Fetcher
+import coil.fetch.SourceResult
 import coil.size.Size
+import okio.buffer
+import okio.source
 import org.oxycblt.auxio.music.Song
 import org.oxycblt.auxio.music.toURI
-import java.lang.Exception
+import java.io.ByteArrayInputStream
+import java.io.InputStream
 
 /**
  * A [Fetcher] for fetching high-quality embedded covers instead of the compressed covers, albeit
- * at the cost of load time & caching.
+ * at the cost of load time & memory usage.
  */
 class QualityCoverFetcher(private val context: Context) : Fetcher<Song> {
+    @Suppress("BlockingMethodInNonBlockingContext")
     override suspend fun fetch(
         pool: BitmapPool,
         data: Song,
@@ -27,29 +30,46 @@ class QualityCoverFetcher(private val context: Context) : Fetcher<Song> {
         options: Options
     ): FetchResult {
         val extractor = MediaMetadataRetriever()
+        val stream: InputStream?
+        val uri: Uri
 
-        extractor.setDataSource(context, data.id.toURI())
+        extractor.use { extractor ->
+            extractor.setDataSource(context, data.id.toURI())
+            val cover = extractor.embeddedPicture
 
-        val bitmap = try {
+            stream = if (cover != null) {
-            val bytes = extractor.embeddedPicture
+                uri = data.id.toURI()
 
-            if (bytes != null) {
+                ByteArrayInputStream(cover)
-                BitmapFactory.decodeByteArray(bytes, 0, bytes.size)
             } else {
-                throw Exception()
+                // Fallback to the compressed cover if the cover loading failed.
+                uri = data.album.coverUri
+
+                // Blocking call, but coil is on a background thread so it doesn't matter
+                context.contentResolver.openInputStream(data.album.coverUri)
+            }
+
+            stream?.use {
+                return SourceResult(
+                    source = stream.source().buffer(),
+                    mimeType = context.contentResolver.getType(uri),
+                    dataSource = DataSource.DISK
+                )
             }
-        } catch (e: Exception) {
-            extractor.release()
-            error("Likely no album art for this item.")
-        } finally {
-            extractor.release()
         }
 
-        return DrawableResult(
+        // If we are here, the extractor likely failed so instead attempt to return the compressed
-            drawable = bitmap.toDrawable(context.resources),
+        // cover instead.
-            isSampled = false,
+        context.contentResolver.openInputStream(data.album.coverUri)?.use { stream ->
-            dataSource = DataSource.DISK
+            return SourceResult(
-        )
+                source = stream.source().buffer(),
+                mimeType = context.contentResolver.getType(uri),
+                dataSource = DataSource.DISK
+            )
+        }
+
+        // If even that failed, then error out entirely.
+        error("Likely no bitmap for this song/album.")
     }
 
     // Group bitmaps by their album so that caching is more efficent

app/src/main/res/values/strings.xml

@@ -68,7 +68,7 @@
     <string name="setting_show_covers_desc">Turn off to save memory usage</string>
 
     <string name="setting_quality_covers">Ignore MediaStore covers</string>
-    <string name="setting_quality_covers_desc">Results in higher quality album covers at the cost of slower loading times and higher memory usage</string>
+    <string name="setting_quality_covers_desc">Results in higher quality album covers, but causes slower loading and higher memory usage</string>
 
     <string name="setting_use_alt_action">Use alternate notification action</string>
     <string name="setting_use_alt_loop">Prefer repeat mode action</string>