Source Code added

mobile/lib/infrastructure/loaders/image_request.dart

@@ -0,0 +1,127 @@
+import 'dart:async';
+import 'dart:ffi';
+import 'dart:ui' as ui;
+
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+import 'package:ffi/ffi.dart';
+import 'package:immich_mobile/domain/models/asset/base_asset.model.dart';
+import 'package:immich_mobile/providers/infrastructure/platform.provider.dart';
+
+part 'local_image_request.dart';
+part 'thumbhash_image_request.dart';
+part 'remote_image_request.dart';
+
+abstract class ImageRequest {
+  static int _nextRequestId = 0;
+
+  final int requestId = _nextRequestId++;
+  bool _isCancelled = false;
+
+  get isCancelled => _isCancelled;
+
+  ImageRequest();
+
+  Future<ImageInfo?> load(ImageDecoderCallback decode, {double scale = 1.0});
+
+  void cancel() {
+    if (_isCancelled) {
+      return;
+    }
+    _isCancelled = true;
+    return _onCancelled();
+  }
+
+  void _onCancelled();
+
+  Future<ui.FrameInfo?> _fromEncodedPlatformImage(int address, int length) async {
+    final pointer = Pointer<Uint8>.fromAddress(address);
+    if (_isCancelled) {
+      malloc.free(pointer);
+      return null;
+    }
+
+    final ui.ImmutableBuffer buffer;
+    try {
+      buffer = await ImmutableBuffer.fromUint8List(pointer.asTypedList(length));
+    } finally {
+      malloc.free(pointer);
+    }
+
+    if (_isCancelled) {
+      buffer.dispose();
+      return null;
+    }
+
+    final descriptor = await ui.ImageDescriptor.encoded(buffer);
+    buffer.dispose();
+    if (_isCancelled) {
+      descriptor.dispose();
+      return null;
+    }
+
+    final codec = await descriptor.instantiateCodec();
+    if (_isCancelled) {
+      descriptor.dispose();
+      codec.dispose();
+      return null;
+    }
+
+    final frame = await codec.getNextFrame();
+    descriptor.dispose();
+    codec.dispose();
+    if (_isCancelled) {
+      frame.image.dispose();
+      return null;
+    }
+
+    return frame;
+  }
+
+  Future<ui.FrameInfo?> _fromDecodedPlatformImage(int address, int width, int height, int rowBytes) async {
+    final pointer = Pointer<Uint8>.fromAddress(address);
+    if (_isCancelled) {
+      malloc.free(pointer);
+      return null;
+    }
+
+    final size = rowBytes * height;
+    final ui.ImmutableBuffer buffer;
+    try {
+      buffer = await ImmutableBuffer.fromUint8List(pointer.asTypedList(size));
+    } finally {
+      malloc.free(pointer);
+    }
+
+    if (_isCancelled) {
+      buffer.dispose();
+      return null;
+    }
+
+    final descriptor = ui.ImageDescriptor.raw(
+      buffer,
+      width: width,
+      height: height,
+      rowBytes: rowBytes,
+      pixelFormat: ui.PixelFormat.rgba8888,
+    );
+    buffer.dispose();
+
+    final codec = await descriptor.instantiateCodec();
+    if (_isCancelled) {
+      descriptor.dispose();
+      codec.dispose();
+      return null;
+    }
+
+    final frame = await codec.getNextFrame();
+    descriptor.dispose();
+    codec.dispose();
+    if (_isCancelled) {
+      frame.image.dispose();
+      return null;
+    }
+
+    return frame;
+  }
+}