download & view local comics

2025-09-27 07:47:24 +00:00 · 2024-10-14 11:10:24 +08:00
parent 5a3537657a
commit c0a0dc59e1
20 changed files with 1467 additions and 158 deletions
--- a/lib/network/images.dart
+++ b/lib/network/images.dart
@@ -0,0 +1,139 @@
+import 'dart:typed_data';
+
+import 'package:venera/foundation/cache_manager.dart';
+import 'package:venera/foundation/comic_source/comic_source.dart';
+import 'package:venera/foundation/consts.dart';
+
+import 'app_dio.dart';
+
+class ImageDownloader {
+  static Stream<ImageDownloadProgress> loadThumbnail(String url, String? sourceKey) async* {
+    final cacheKey = "$url@$sourceKey";
+    final cache = await CacheManager().findCache(cacheKey);
+
+    if (cache != null) {
+      var data = await cache.readAsBytes();
+      yield ImageDownloadProgress(
+        currentBytes: data.length,
+        totalBytes: data.length,
+        imageBytes: data,
+      );
+    }
+
+    var configs = <String, dynamic>{};
+    if (sourceKey != null) {
+      var comicSource = ComicSource.find(sourceKey);
+      configs = comicSource!.getThumbnailLoadingConfig?.call(url) ?? {};
+    }
+    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'] ?? url,
+        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) {
+        yield ImageDownloadProgress(
+          currentBytes: buffer.length,
+          totalBytes: expectedBytes,
+        );
+      }
+    }
+
+    if(configs['onResponse'] != null) {
+      buffer = configs['onResponse'](buffer);
+    }
+
+    await CacheManager().writeCache(cacheKey, buffer);
+    yield ImageDownloadProgress(
+      currentBytes: buffer.length,
+      totalBytes: buffer.length,
+      imageBytes: Uint8List.fromList(buffer),
+    );
+  }
+
+  static Stream<ImageDownloadProgress> loadComicImage(String imageKey, String? sourceKey, String cid, String eid) async* {
+    final cacheKey = "$imageKey@$sourceKey@$cid@$eid";
+    final cache = await CacheManager().findCache(cacheKey);
+
+    if (cache != null) {
+      var data = await cache.readAsBytes();
+      yield ImageDownloadProgress(
+        currentBytes: data.length,
+        totalBytes: data.length,
+        imageBytes: data,
+      );
+    }
+
+    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) {
+        yield ImageDownloadProgress(
+          currentBytes: buffer.length,
+          totalBytes: expectedBytes,
+        );
+      }
+    }
+
+    if(configs['onResponse'] != null) {
+      buffer = configs['onResponse'](buffer);
+    }
+
+    await CacheManager().writeCache(cacheKey, buffer);
+    yield ImageDownloadProgress(
+      currentBytes: buffer.length,
+      totalBytes: buffer.length,
+      imageBytes: Uint8List.fromList(buffer),
+    );
+  }
+}
+
+class ImageDownloadProgress {
+  final int currentBytes;
+
+  final int totalBytes;
+
+  final Uint8List? imageBytes;
+
+  const ImageDownloadProgress({
+    required this.currentBytes,
+    required this.totalBytes,
+    this.imageBytes,
+  });
+}