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;
+  }
+}

mobile/lib/infrastructure/loaders/local_image_request.dart

@@ -0,0 +1,38 @@
+part of 'image_request.dart';
+
+class LocalImageRequest extends ImageRequest {
+  final String localId;
+  final int width;
+  final int height;
+  final AssetType assetType;
+
+  LocalImageRequest({required this.localId, required ui.Size size, required this.assetType})
+    : width = size.width.toInt(),
+      height = size.height.toInt();
+
+  @override
+  Future<ImageInfo?> load(ImageDecoderCallback decode, {double scale = 1.0}) async {
+    if (_isCancelled) {
+      return null;
+    }
+
+    final info = await localImageApi.requestImage(
+      localId,
+      requestId: requestId,
+      width: width,
+      height: height,
+      isVideo: assetType == AssetType.video,
+    );
+    if (info == null) {
+      return null;
+    }
+
+    final frame = await _fromDecodedPlatformImage(info["pointer"]!, info["width"]!, info["height"]!, info["rowBytes"]!);
+    return frame == null ? null : ImageInfo(image: frame.image, scale: scale);
+  }
+
+  @override
+  Future<void> _onCancelled() {
+    return localImageApi.cancelRequest(requestId);
+  }
+}

mobile/lib/infrastructure/loaders/remote_image_request.dart

@@ -0,0 +1,29 @@
+part of 'image_request.dart';
+
+class RemoteImageRequest extends ImageRequest {
+  final String uri;
+  final Map<String, String> headers;
+
+  RemoteImageRequest({required this.uri, required this.headers});
+
+  @override
+  Future<ImageInfo?> load(ImageDecoderCallback decode, {double scale = 1.0}) async {
+    if (_isCancelled) {
+      return null;
+    }
+
+    final info = await remoteImageApi.requestImage(uri, headers: headers, requestId: requestId);
+    final frame = switch (info) {
+      {'pointer': int pointer, 'length': int length} => await _fromEncodedPlatformImage(pointer, length),
+      {'pointer': int pointer, 'width': int width, 'height': int height, 'rowBytes': int rowBytes} =>
+        await _fromDecodedPlatformImage(pointer, width, height, rowBytes),
+      _ => null,
+    };
+    return frame == null ? null : ImageInfo(image: frame.image, scale: scale);
+  }
+
+  @override
+  Future<void> _onCancelled() {
+    return remoteImageApi.cancelRequest(requestId);
+  }
+}

mobile/lib/infrastructure/loaders/thumbhash_image_request.dart

@@ -0,0 +1,21 @@
+part of 'image_request.dart';
+
+class ThumbhashImageRequest extends ImageRequest {
+  final String thumbhash;
+
+  ThumbhashImageRequest({required this.thumbhash});
+
+  @override
+  Future<ImageInfo?> load(ImageDecoderCallback decode, {double scale = 1.0}) async {
+    if (_isCancelled) {
+      return null;
+    }
+
+    final Map<String, int> info = await localImageApi.getThumbhash(thumbhash);
+    final frame = await _fromDecodedPlatformImage(info["pointer"]!, info["width"]!, info["height"]!, info["rowBytes"]!);
+    return frame == null ? null : ImageInfo(image: frame.image, scale: scale);
+  }
+
+  @override
+  void _onCancelled() {}
+}