comic reading

lib/foundation/image_provider/cached_image.dart

@@ -1,5 +1,4 @@
 import 'dart:async' show Future, StreamController;
-import 'package:dio/dio.dart';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/material.dart';
 import 'package:venera/foundation/cache_manager.dart';

lib/foundation/image_provider/reader_image.dart

@@ -0,0 +1,81 @@
+import 'dart:async' show Future, StreamController;
+import 'package:flutter/foundation.dart';
+import 'package:flutter/material.dart';
+import 'package:venera/foundation/cache_manager.dart';
+import 'package:venera/foundation/comic_source/comic_source.dart';
+import 'package:venera/foundation/consts.dart';
+import 'package:venera/network/app_dio.dart';
+import 'base_image_provider.dart';
+import 'reader_image.dart' as image_provider;
+
+class ReaderImageProvider
+    extends BaseImageProvider<image_provider.ReaderImageProvider> {
+  /// Image provider for normal image.
+  const ReaderImageProvider(this.imageKey, this.sourceKey, this.cid, this.eid);
+
+  final String imageKey;
+
+  final String? sourceKey;
+
+  final String cid;
+
+  final String eid;
+
+  @override
+  Future<Uint8List> load(StreamController<ImageChunkEvent> chunkEvents) async {
+    final cacheKey = "$imageKey@$sourceKey@$cid@$eid";
+    final cache = await CacheManager().findCache(cacheKey);
+
+    if (cache != null) {
+      return await cache.readAsBytes();
+    }
+
+    var configs = <String, dynamic>{};
+    if (sourceKey != null) {
+      var comicSource = ComicSource.find(sourceKey!);
+      configs = comicSource!.getImageLoadingConfig?.call(imageKey, cid, eid) ?? {};
+    }
+    configs['headers'] ??= {
+      'user-agent': webUA,
+    };
+
+    var dio = AppDio(BaseOptions(
+      headers: configs['headers'],
+      method: configs['method'] ?? 'GET',
+      responseType: ResponseType.stream,
+    ));
+
+    var req = await dio.request<ResponseBody>(configs['url'] ?? imageKey,
+        data: configs['data']);
+    var stream = req.data?.stream ?? (throw "Error: Empty response body.");
+    int? expectedBytes = req.data!.contentLength;
+    if (expectedBytes == -1) {
+      expectedBytes = null;
+    }
+    var buffer = <int>[];
+    await for (var data in stream) {
+      buffer.addAll(data);
+      if (expectedBytes != null) {
+        chunkEvents.add(ImageChunkEvent(
+          cumulativeBytesLoaded: buffer.length,
+          expectedTotalBytes: expectedBytes,
+        ));
+      }
+    }
+
+    if(configs['onResponse'] != null) {
+      buffer = configs['onResponse'](buffer);
+    }
+
+    await CacheManager().writeCache(cacheKey, buffer);
+    return Uint8List.fromList(buffer);
+  }
+
+  @override
+  Future<ReaderImageProvider> obtainKey(ImageConfiguration configuration) {
+    return SynchronousFuture(this);
+  }
+
+  @override
+  String get key => "$imageKey@$sourceKey@$cid@$eid";
+}