Add HistoryImageProvider

lib/foundation/image_provider/history_image_provider.dart

@@ -0,0 +1,57 @@
+import 'dart:async' show Future, StreamController;
+import 'package:flutter/foundation.dart';
+import 'package:flutter/material.dart';
+import 'package:venera/foundation/local.dart';
+import 'package:venera/network/images.dart';
+import '../history.dart';
+import 'base_image_provider.dart';
+import 'history_image_provider.dart' as image_provider;
+
+class HistoryImageProvider
+    extends BaseImageProvider<image_provider.HistoryImageProvider> {
+  /// Image provider for normal image.
+  ///
+  /// [url] is the url of the image. Local file path is also supported.
+  const HistoryImageProvider(this.history);
+
+  final History history;
+
+  @override
+  Future<Uint8List> load(StreamController<ImageChunkEvent> chunkEvents) async {
+    var url = history.cover;
+    if (!url.contains('/')) {
+      var localComic = LocalManager().find(history.id, history.type);
+      if (localComic != null) {
+        return localComic.coverFile.readAsBytes();
+      }
+      var comicSource =
+          history.type.comicSource ?? (throw "Comic source not found.");
+      var comic = await comicSource.loadComicInfo!(history.id);
+      url = comic.data.cover;
+      history.cover = url;
+      HistoryManager().addHistory(history);
+    }
+    await for (var progress in ImageDownloader.loadThumbnail(
+      url,
+      history.type.sourceKey,
+      history.id,
+    )) {
+      chunkEvents.add(ImageChunkEvent(
+        cumulativeBytesLoaded: progress.currentBytes,
+        expectedTotalBytes: progress.totalBytes,
+      ));
+      if (progress.imageBytes != null) {
+        return progress.imageBytes!;
+      }
+    }
+    throw "Error: Empty response body.";
+  }
+
+  @override
+  Future<HistoryImageProvider> obtainKey(ImageConfiguration configuration) {
+    return SynchronousFuture(this);
+  }
+
+  @override
+  String get key => "history${history.id}${history.type.value}";
+}