전역 구조 리팩터링 및 테스트 확장

lib/widgets/components/responsive.dart

@@ -1,6 +1,98 @@
+import 'package:flutter/widgets.dart';
+
 const double desktopBreakpoint = 1200;
 const double tabletBreakpoint = 960;
 
+enum DeviceBreakpoint { mobile, tablet, desktop }
+
+DeviceBreakpoint breakpointForWidth(double width) {
+  if (width >= desktopBreakpoint) {
+    return DeviceBreakpoint.desktop;
+  }
+  if (width >= tabletBreakpoint) {
+    return DeviceBreakpoint.tablet;
+  }
+  return DeviceBreakpoint.mobile;
+}
+
 bool isDesktop(double width) => width >= desktopBreakpoint;
-bool isTablet(double width) => width >= tabletBreakpoint && width < desktopBreakpoint;
+bool isTablet(double width) =>
+    width >= tabletBreakpoint && width < desktopBreakpoint;
 bool isMobile(double width) => width < tabletBreakpoint;
+
+bool isDesktopContext(BuildContext context) =>
+    isDesktop(MediaQuery.of(context).size.width);
+bool isTabletContext(BuildContext context) =>
+    isTablet(MediaQuery.of(context).size.width);
+bool isMobileContext(BuildContext context) =>
+    isMobile(MediaQuery.of(context).size.width);
+
+class ResponsiveBreakpoints {
+  ResponsiveBreakpoints._(this.width) : breakpoint = breakpointForWidth(width);
+
+  final double width;
+  final DeviceBreakpoint breakpoint;
+
+  bool get isMobile => breakpoint == DeviceBreakpoint.mobile;
+  bool get isTablet => breakpoint == DeviceBreakpoint.tablet;
+  bool get isDesktop => breakpoint == DeviceBreakpoint.desktop;
+
+  static ResponsiveBreakpoints of(BuildContext context) {
+    final size = MediaQuery.of(context).size;
+    return ResponsiveBreakpoints._(size.width);
+  }
+}
+
+class ResponsiveLayoutBuilder extends StatelessWidget {
+  const ResponsiveLayoutBuilder({
+    super.key,
+    required this.mobile,
+    this.tablet,
+    required this.desktop,
+  });
+
+  final WidgetBuilder mobile;
+  final WidgetBuilder? tablet;
+  final WidgetBuilder desktop;
+
+  @override
+  Widget build(BuildContext context) {
+    return LayoutBuilder(
+      builder: (context, constraints) {
+        final breakpoint = breakpointForWidth(constraints.maxWidth);
+        switch (breakpoint) {
+          case DeviceBreakpoint.mobile:
+            return mobile(context);
+          case DeviceBreakpoint.tablet:
+            final tabletBuilder = tablet ?? desktop;
+            return tabletBuilder(context);
+          case DeviceBreakpoint.desktop:
+            return desktop(context);
+        }
+      },
+    );
+  }
+}
+
+class ResponsiveVisibility extends StatelessWidget {
+  const ResponsiveVisibility({
+    super.key,
+    required this.child,
+    this.replacement = const SizedBox.shrink(),
+    this.visibleOn = const {
+      DeviceBreakpoint.mobile,
+      DeviceBreakpoint.tablet,
+      DeviceBreakpoint.desktop,
+    },
+  });
+
+  final Widget child;
+  final Widget replacement;
+  final Set<DeviceBreakpoint> visibleOn;
+
+  @override
+  Widget build(BuildContext context) {
+    final breakpoint = ResponsiveBreakpoints.of(context).breakpoint;
+    return visibleOn.contains(breakpoint) ? child : replacement;
+  }
+}