max-width attribute and auto-margins on network images for Flutter 3.10

lib/src/builtins/image_builtin.dart

@@ -201,7 +201,7 @@ class ImageBuiltIn extends HtmlExtension {
         element.src,
         width: imageStyle.width?.value,
         height: imageStyle.height?.value,
-        fit: BoxFit.fill,
+        fit: BoxFit.contain,
         headers: networkHeaders,
         errorBuilder: (ctx, error, stackTrace) {
           return Text(

lib/src/css_box_widget.dart

@@ -60,7 +60,8 @@ class CssBoxWidget extends StatelessWidget {
     final padding = style.padding?.resolve(direction);
 
     return _CSSBoxRenderer(
-      width: style.width ?? Width.auto(),
+      width:
+          _calculateMaxedWidth(context, style) ?? style.width ?? Width.auto(),
       height: style.height ?? Height.auto(),
       paddingSize: padding?.collapsedSize ?? Size.zero,
       borderSize: style.border?.dimensions.collapsedSize ?? Size.zero,
@@ -90,6 +91,29 @@ class CssBoxWidget extends StatelessWidget {
     );
   }
 
+  /// Returns the width capped with maxWidth if necessary.
+  static Width? _calculateMaxedWidth(BuildContext context, Style style) {
+    // We only need to calculate something if we have a width and it needs to be capped.
+    if (style.maxWidth == null || style.width == null) return null;
+
+    // If our max is a percentage, we want to look at the size available and not be bigger than that.
+    // TODO In the else case, we should have something to compare across different units, as for now some cases won't be handled.
+    if (style.maxWidth!.unit == Unit.percent && style.width!.unit == Unit.px) {
+      return Width(
+        MediaQuery.of(context).size.width * (style.maxWidth!.value / 100),
+        style.width!.unit,
+      );
+    } else if (style.width!.unit == style.maxWidth!.unit &&
+        style.width!.value > style.maxWidth!.value) {
+      return Width(
+        style.maxWidth!.value,
+        style.maxWidth!.unit,
+      );
+    } else {
+      return null;
+    }
+  }
+
   /// Takes a list of InlineSpan children and generates a Text.rich Widget
   /// containing those children.
   static Widget _generateWidgetChild(List<InlineSpan> children, Style style) {

lib/src/css_parser.dart

@@ -656,6 +656,10 @@ Style declarationsToStyle(Map<String, List<css.Expression>> declarations) {
           style.width =
               ExpressionMapping.expressionToWidth(value.first) ?? style.width;
           break;
+        case 'max-width':
+          style.maxWidth = ExpressionMapping.expressionToWidth(value.first) ??
+              style.maxWidth;
+          break;
       }
     }
   });
@@ -1230,6 +1234,8 @@ class ExpressionMapping {
           double.parse(value.text.replaceAll(RegExp(r'\s+(\d+\.\d+)\s+'), ''));
       Unit unit = _unitMap(value.unit);
       return LengthOrPercent(number, unit);
+    } else if (value is css.PercentageTerm) {
+      return LengthOrPercent(double.parse(value.text), Unit.percent);
     }
 
     //Ignore un-parsable input

lib/src/style.dart

@@ -193,6 +193,12 @@ class Style {
   /// Default: Width.auto()
   Width? width;
 
+  /// CSS attribute "`max-width`"
+  ///
+  /// Inherited: no,
+  /// Default: null
+  Width? maxWidth;
+
   /// CSS attribute "`word-spacing`"
   ///
   /// Inherited: yes,
@@ -262,6 +268,7 @@ class Style {
     this.verticalAlign = VerticalAlign.baseline,
     this.whiteSpace,
     this.width,
+    this.maxWidth,
     this.wordSpacing,
     this.before,
     this.after,
@@ -355,6 +362,7 @@ class Style {
       verticalAlign: other.verticalAlign,
       whiteSpace: other.whiteSpace,
       width: other.width,
+      maxWidth: other.maxWidth,
       wordSpacing: other.wordSpacing,
       before: other.before,
       after: other.after,
@@ -440,6 +448,7 @@ class Style {
     VerticalAlign? verticalAlign,
     WhiteSpace? whiteSpace,
     Width? width,
+    Width? maxWidth,
     double? wordSpacing,
     String? before,
     String? after,
@@ -483,6 +492,7 @@ class Style {
       verticalAlign: verticalAlign ?? this.verticalAlign,
       whiteSpace: whiteSpace ?? this.whiteSpace,
       width: width ?? this.width,
+      maxWidth: maxWidth ?? this.maxWidth,
       wordSpacing: wordSpacing ?? this.wordSpacing,
       before: beforeAfterNull == true ? null : before ?? this.before,
       after: beforeAfterNull == true ? null : after ?? this.after,