Add BitmapProvider class

app/src/main/kotlin/it/vfsfitvnm/vimusic/service/BitmapProvider.kt

@@ -0,0 +1,71 @@
+package it.vfsfitvnm.vimusic.service
+
+import android.content.Context
+import android.content.res.Configuration
+import android.graphics.Bitmap
+import android.graphics.drawable.BitmapDrawable
+import android.net.Uri
+import androidx.core.graphics.applyCanvas
+import coil.Coil
+import coil.request.Disposable
+import coil.request.ImageRequest
+import it.vfsfitvnm.vimusic.utils.thumbnail
+
+context(Context)
+class BitmapProvider(
+    private val bitmapSize: Int,
+    private val colorProvider: (isSystemInDarkMode: Boolean) -> Int
+) {
+    private var lastUri: Uri? = null
+    private var lastBitmap: Bitmap? = null
+    private var lastIsSystemInDarkMode = false
+
+    private var lastEnqueued: Disposable? = null
+
+    private lateinit var defaultBitmap: Bitmap
+
+    val bitmap: Bitmap
+        get() = lastBitmap ?: defaultBitmap
+
+    init {
+        setDefaultBitmap()
+    }
+
+    fun setDefaultBitmap(): Boolean {
+        val isSystemInDarkMode = resources.configuration.uiMode and
+                Configuration.UI_MODE_NIGHT_MASK == Configuration.UI_MODE_NIGHT_YES
+
+        if (::defaultBitmap.isInitialized && isSystemInDarkMode == lastIsSystemInDarkMode) return false
+
+        lastIsSystemInDarkMode = isSystemInDarkMode
+
+        defaultBitmap = Bitmap.createBitmap(bitmapSize, bitmapSize, Bitmap.Config.ARGB_8888).applyCanvas {
+            drawColor(colorProvider(isSystemInDarkMode))
+        }
+
+        return lastBitmap == null
+    }
+
+    fun load(uri: Uri?, onDone: (Bitmap) -> Unit) {
+        if (lastUri == uri) return
+
+        lastEnqueued?.dispose()
+        lastUri = uri
+
+        lastEnqueued = Coil.imageLoader(applicationContext).enqueue(
+            ImageRequest.Builder(applicationContext)
+                .data(uri.thumbnail(bitmapSize))
+                .listener(
+                    onError = { _, _ ->
+                        lastBitmap = null
+                        onDone(bitmap)
+                    },
+                    onSuccess = { _, result ->
+                        lastBitmap = (result.drawable as BitmapDrawable).bitmap
+                        onDone(bitmap)
+                    }
+                )
+                .build()
+        )
+    }
+}