immich/mobile/lib/presentation/widgets/images/image_provider.dart

import 'package:flutter/widgets.dart';
import 'package:immich_mobile/domain/models/asset/base_asset.model.dart';
import 'package:immich_mobile/domain/models/setting.model.dart';
import 'package:immich_mobile/domain/services/setting.service.dart';
import 'package:immich_mobile/presentation/widgets/images/local_image_provider.dart';
import 'package:immich_mobile/presentation/widgets/images/remote_image_provider.dart';
import 'package:immich_mobile/presentation/widgets/timeline/constants.dart';
import 'package:immich_mobile/infrastructure/repositories/asset_media.repository.dart';

abstract class CancellableImageProvider {
  void cancel();
}

mixin class CancellableImageProviderMixin implements CancellableImageProvider {
  ImageRequest? request;

  @override
  void cancel() {
    final request = this.request;
    if (request == null) {
      return;
    }
    this.request = null;
    return request.cancel();
  }
}

ImageProvider getFullImageProvider(BaseAsset asset, {Size size = const Size(1080, 1920)}) {
  // Create new provider and cache it
  final ImageProvider provider;
  if (_shouldUseLocalAsset(asset)) {
    final id = asset is LocalAsset ? asset.id : (asset as RemoteAsset).localId!;
    provider = LocalFullImageProvider(id: id, size: size);
  } else {
    final String assetId;
    if (asset is LocalAsset && asset.hasRemote) {
      assetId = asset.remoteId!;
    } else if (asset is RemoteAsset) {
      assetId = asset.id;
    } else {
      throw ArgumentError("Unsupported asset type: ${asset.runtimeType}");
    }
    provider = RemoteFullImageProvider(assetId: assetId);
  }

  return provider;
}

ImageProvider getThumbnailImageProvider({BaseAsset? asset, String? remoteId, Size size = kThumbnailResolution}) {
  assert(asset != null || remoteId != null, 'Either asset or remoteId must be provided');

  if (remoteId != null) {
    return RemoteThumbProvider(assetId: remoteId);
  }

  if (_shouldUseLocalAsset(asset!)) {
    final id = asset is LocalAsset ? asset.id : (asset as RemoteAsset).localId!;
    return LocalThumbProvider(id: id, size: size);
  }

  final String assetId;
  if (asset is LocalAsset && asset.hasRemote) {
    assetId = asset.remoteId!;
  } else if (asset is RemoteAsset) {
    assetId = asset.id;
  } else {
    throw ArgumentError("Unsupported asset type: ${asset.runtimeType}");
  }

  return RemoteThumbProvider(assetId: assetId);
}

bool _shouldUseLocalAsset(BaseAsset asset) =>
    asset.hasLocal && (!asset.hasRemote || !AppSetting.get(Setting.preferRemoteImage));

ImageInfo? getCachedImage(ImageProvider key) {
  ImageInfo? thumbnail;
  final ImageStreamCompleter? stream = PaintingBinding.instance.imageCache.putIfAbsent(
    key,
    () => throw Exception(), // don't bother loading if it isn't cached
    onError: (_, __) {},
  );

  if (stream != null) {
    void listener(ImageInfo info, bool synchronousCall) {
      thumbnail = info;
    }

    try {
      stream.addListener(ImageStreamListener(listener));
    } finally {
      stream.removeListener(ImageStreamListener(listener));
    }
  }

  return thumbnail;
}