refactor: Update TaroResizeOption to use sealed classes

lib/src/taro.dart

@@ -23,11 +23,7 @@ class Taro {
   final _loader = TaroLoader();
 
   /// The [TaroResizeOption] used to resize images.
-  TaroResizeOption _resizeOption = const (
-    mode: TaroResizeMode.skip,
-    maxWidth: null,
-    maxHeight: null,
-  );
+  TaroResizeOption _resizeOption = const TaroResizeOptionSkip();
 
   /// The [TaroResizeOption] used to resize images.
   /// Changing this option will affect all image loading.
@@ -94,10 +90,10 @@ class Taro {
       headerOption: headerOption ?? _headerOption,
     );
 
-    if (resizeOption?.mode == TaroResizeMode.memory) {
+    if (resizeOption is TaroResizeOptionMemory) {
       return ResizeImage.resizeIfNeeded(
-        resizeOption?.maxWidth,
-        resizeOption?.maxHeight,
+        resizeOption.maxWidth,
+        resizeOption.maxHeight,
         image,
       );
     }

lib/src/taro_resizer.dart

@@ -16,116 +16,117 @@ class TaroResizer {
     required String contentType,
     required TaroResizeOption resizeOption,
   }) async {
-    if (resizeOption.mode case TaroResizeMode.skip || TaroResizeMode.memory) {
-      // do nothing
-      return (
-        bytes: bytes,
-        contentType: contentType,
-      );
-    }
+    switch (resizeOption) {
+      case TaroResizeOptionSkip() || TaroResizeOptionMemory():
+        // do nothing
+        return (
+          bytes: bytes,
+          contentType: contentType,
+        );
+      case TaroResizeOptionDisk(
+          format: final optionFormat,
+          maxWidth: final optionMaxWidth,
+          maxHeight: final optionMaxHeight,
+        ):
+        final originalImage = img.decodeImage(bytes);
+        if (originalImage == null) {
+          return throw TaroResizeException(
+            exception: Exception('Failed to decode image.'),
+          );
+        }
 
-    final originalImage = img.decodeImage(bytes);
-    if (originalImage == null) {
-      return throw TaroResizeException(
-        exception: Exception('Failed to decode image.'),
-      );
-    }
+        final int maxWidth;
+        if (optionMaxWidth != null) {
+          maxWidth = min(optionMaxWidth, originalImage.width);
+        } else {
+          maxWidth = originalImage.width;
+        }
 
-    final int maxWidth;
-    if (resizeOption.maxWidth != null) {
-      maxWidth = min(resizeOption.maxWidth!, originalImage.width);
-    } else {
-      maxWidth = originalImage.width;
-    }
+        final int maxHeight;
+        if (optionMaxHeight != null) {
+          maxHeight = min(optionMaxHeight, originalImage.height);
+        } else {
+          maxHeight = originalImage.height;
+        }
 
-    final int maxHeight;
-    if (resizeOption.maxHeight != null) {
-      maxHeight = min(resizeOption.maxHeight!, originalImage.height);
-    } else {
-      maxHeight = originalImage.height;
-    }
+        if (maxWidth == originalImage.width &&
+            maxHeight == originalImage.height) {
+          return (
+            bytes: bytes,
+            contentType: contentType,
+          );
+        }
 
-    if (maxWidth == originalImage.width && maxHeight == originalImage.height) {
-      return (
-        bytes: bytes,
-        contentType: contentType,
-      );
-    }
+        final cmd = img.Command()
+          ..image(originalImage)
+          ..copyResize(
+            width: maxWidth,
+            height: maxHeight,
+          );
 
-    final cmd = img.Command()
-      ..image(originalImage)
-      ..copyResize(
-        width: maxWidth,
-        height: maxHeight,
-      );
+        final String encodeImageType;
+        switch (optionFormat) {
+          case TaroResizeFormat.original:
+            switch (contentType) {
+              case 'image/gif':
+              case 'image/jpeg':
+              case 'image/png':
+              case 'image/bmp':
+              case 'image/x-icon':
+              case 'image/tiff':
+                encodeImageType = contentType;
+              default:
+                encodeImageType = 'image/png';
+            }
+          case TaroResizeFormat.gif:
+            encodeImageType = 'image/gif';
+          case TaroResizeFormat.jpeg:
+            encodeImageType = 'image/jpeg';
+          case TaroResizeFormat.png:
+            encodeImageType = 'image/png';
+          case TaroResizeFormat.bmp:
+            encodeImageType = 'image/bmp';
+          case TaroResizeFormat.ico:
+            encodeImageType = 'image/x-icon';
+          case TaroResizeFormat.tiff:
+            encodeImageType = 'image/tiff';
+        }
 
-    final String encodeImageType;
-    switch (resizeOption.mode) {
-      case TaroResizeMode.skip:
-        // this case is not possible
-        throw Exception('This case is not possible.');
-      case TaroResizeMode.original:
-        switch (contentType) {
+        switch (encodeImageType) {
           case 'image/gif':
+            cmd.encodeGif();
           case 'image/jpeg':
+            cmd.encodeJpg();
           case 'image/png':
+            cmd.encodePng();
           case 'image/bmp':
+            cmd.encodeBmp();
           case 'image/x-icon':
+            cmd.encodeIco();
           case 'image/tiff':
-            encodeImageType = contentType;
+            cmd.encodeTiff();
           default:
-            encodeImageType = 'image/png';
+            // if the contentType is not supported, encode the image to png
+            cmd.encodePng();
         }
-      case TaroResizeMode.gif:
-        encodeImageType = 'image/gif';
-      case TaroResizeMode.jpeg:
-        encodeImageType = 'image/jpeg';
-      case TaroResizeMode.png:
-        encodeImageType = 'image/png';
-      case TaroResizeMode.bmp:
-        encodeImageType = 'image/bmp';
-      case TaroResizeMode.ico:
-        encodeImageType = 'image/x-icon';
-      case TaroResizeMode.tiff:
-        encodeImageType = 'image/tiff';
-      default:
-        encodeImageType = 'image/png';
-    }
 
-    switch (encodeImageType) {
-      case 'image/gif':
-        cmd.encodeGif();
-      case 'image/jpeg':
-        cmd.encodeJpg();
-      case 'image/png':
-        cmd.encodePng();
-      case 'image/bmp':
-        cmd.encodeBmp();
-      case 'image/x-icon':
-        cmd.encodeIco();
-      case 'image/tiff':
-        cmd.encodeTiff();
-      default:
-        // if the contentType is not supported, encode the image to png
-        cmd.encodePng();
-    }
+        final Uint8List? result;
+        try {
+          result = await cmd.getBytesThread();
+        } on Exception catch (exception) {
+          throw TaroResizeException(
+            exception: exception,
+          );
+        }
 
-    final Uint8List? result;
-    try {
-      result = await cmd.getBytesThread();
-    } on Exception catch (exception) {
-      throw TaroResizeException(
-        exception: exception,
-      );
-    }
+        if (result == null) {
+          throw const TaroResizeFailedException();
+        }
 
-    if (result == null) {
-      throw const TaroResizeFailedException();
+        return (
+          bytes: result,
+          contentType: encodeImageType,
+        );
     }
-
-    return (
-      bytes: result,
-      contentType: encodeImageType,
-    );
   }
 }

lib/src/taro_type.dart

@@ -1,43 +1,65 @@
-/// [TaroRequestOption] is used to configure the options for a resizing request.
-typedef TaroResizeOption = ({
-  /// The resize mode of the image.
-  TaroResizeMode mode,
+/// The [TaroResizeOption] is used to determine how images are resized and saved.
+/// Please refer to [https://pub.dev/packages/image] for supported formats.
+sealed class TaroResizeOption {
+  const TaroResizeOption();
+}
 
-  /// The maximum width of the image. If null, the width is not limited.
-  int? maxWidth,
+/// The image is not resized, saved original size and format.
+class TaroResizeOptionSkip extends TaroResizeOption {
+  const TaroResizeOptionSkip();
+}
 
-  /// The maximum height of the image. If null, the height is not limited.
-  int? maxHeight,
-});
+/// The image is resized in memory, saved original size and format.
+class TaroResizeOptionMemory extends TaroResizeOption {
+  const TaroResizeOptionMemory({
+    required this.maxWidth,
+    required this.maxHeight,
+  });
 
-/// The [TaroResizeMode] enum is used to determine how images are resized.
-/// Please refer to [https://pub.dev/packages/image] for supported formats.
-enum TaroResizeMode {
-  /// The image is not resized.
-  skip,
+  /// The maximum width of the image.
+  final int maxWidth;
 
-  /// The image is resized and saved original image.
-  memory,
+  /// The maximum height of the image.
+  final int maxHeight;
+}
+
+class TaroResizeOptionDisk extends TaroResizeOption {
+  const TaroResizeOptionDisk({
+    required this.format,
+    this.maxWidth,
+    this.maxHeight,
+  });
+
+  /// The format of the image.
+  final TaroResizeFormat format;
+
+  /// The maximum width of the image. If null, the width is not limited.
+  final int? maxWidth;
+
+  /// The maximum height of the image. If null, the height is not limited.
+  final int? maxHeight;
+}
 
-  /// The image is resized to the original contentType and saved cache.
+enum TaroResizeFormat {
+  /// The original format of the image.
   original,
 
-  /// The image is resized to a gif and saved cache.
+  /// The image is saved as a gif.
   gif,
 
-  /// The image is resized to a jpg and saved cache.
+  /// The image is saved as a jpeg.
   jpeg,
 
-  /// The image is resized to a png and saved cache.
+  /// The image is saved as a png.
   png,
 
-  /// The image is resized to a bmp and saved cache.
+  /// The image is saved as a bmp.
   bmp,
 
-  /// The image is resized to a ico and saved cache.
+  /// The image is saved as an icon.
   ico,
 
-  /// The image is resized to a tiff and saved cache.
+  /// The image is saved as a tiff.
   tiff,
 }
 

test/taro_loader_network_test.dart

@@ -27,11 +27,7 @@ void main() {
   );
 
   final bodyBytes = Uint8List(100);
-  const resizeOption = (
-    mode: TaroResizeMode.skip,
-    maxWidth: null,
-    maxHeight: null,
-  );
+  const resizeOption = TaroResizeOptionSkip();
   const headerOption = (
     checkMaxAgeIfExist: false,
     ifThrowMaxAgeHeaderError: false,

test/taro_loader_network_test.mocks.dart

@@ -125,11 +125,7 @@ class MockTaroResizer extends _i1.Mock implements _i5.TaroResizer {
   _i3.Future<({_i4.Uint8List bytes, String contentType})> resizeIfNeeded({
     required _i4.Uint8List? bytes,
     required String? contentType,
-    required ({
-      int? maxHeight,
-      int? maxWidth,
-      _i6.TaroResizeMode mode
-    })? resizeOption,
+    required _i6.TaroResizeOption? resizeOption,
   }) =>
       (super.noSuchMethod(
         Invocation.method(