TF-4171 Display tag in mailbox list

core/lib/core.dart

@@ -18,6 +18,7 @@ export 'presentation/extensions/map_extensions.dart';
 export 'presentation/extensions/either_view_state_extension.dart';
 export 'presentation/extensions/media_type_extension.dart';
 export 'presentation/extensions/scroll_controller_extension.dart';
+export 'presentation/extensions/hex_color_extension.dart';
 
 // Exceptions
 export 'domain/exceptions/download_file_exception.dart';
@@ -63,6 +64,7 @@ export 'utils/web_link_generator.dart';
 export 'utils/sentry/sentry_manager.dart';
 export 'utils/config/env_loader.dart';
 export 'utils/sentry/sentry_dio_helper.dart';
+export 'utils/widget_utils.dart';
 
 // Views
 export 'presentation/views/text/slogan_builder.dart';

core/lib/presentation/extensions/hex_color_extension.dart

@@ -0,0 +1,18 @@
+import 'package:flutter/material.dart';
+
+extension HexColorExtension on String {
+  Color toColor({Color fallback = Colors.transparent}) {
+    try {
+      final hex = replaceAll('#', '');
+
+      if (hex.length != 6 && hex.length != 8) {
+        return fallback;
+      }
+
+      final fullHex = hex.length == 6 ? 'FF$hex' : hex;
+      return Color(int.parse(fullHex, radix: 16));
+    } catch (_) {
+      return fallback;
+    }
+  }
+}

core/lib/utils/widget_utils.dart

@@ -0,0 +1,33 @@
+import 'package:flutter/material.dart';
+
+class WidgetUtils {
+  WidgetUtils._();
+
+  static double measureTextWidth({
+    required String text,
+    double fallbackWidth = 0,
+    TextStyle? style,
+    Locale? locale,
+    double? horizontalPadding,
+  }) {
+    try {
+      final textPainter = TextPainter(
+        text: TextSpan(
+          text: text,
+          style: style,
+          locale: locale,
+        ),
+        maxLines: 1,
+        textDirection: TextDirection.ltr,
+      )..layout();
+
+      if (horizontalPadding != null) {
+        return textPainter.width + horizontalPadding * 2;
+      } else {
+        return textPainter.width;
+      }
+    } catch (e) {
+      return fallbackWidth;
+    }
+  }
+}

core/test/presentation/extensions/hex_color_extension_test.dart

@@ -0,0 +1,57 @@
+import 'package:core/presentation/extensions/hex_color_extension.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+void main() {
+  group('HexColorExtension.toColor', () {
+    test('should convert 6-char hex (#RRGGBB) to Color with default alpha FF',
+        () {
+      final color = "#FF0000".toColor();
+      expect(color, const Color(0xFFFF0000));
+    });
+
+    test('should convert 8-char hex (#AARRGGBB) correctly', () {
+      final color = "#80FF0000".toColor();
+      expect(color, const Color(0x80FF0000));
+    });
+
+    test('should handle string without # prefix', () {
+      final color = "00FF00".toColor();
+      expect(color, const Color(0xFF00FF00));
+    });
+
+    test('should return fallback when hex is invalid', () {
+      const fallback = Colors.blue;
+      final color = "INVALID".toColor(fallback: fallback);
+      expect(color, fallback);
+    });
+
+    test('should return fallback when hex contains non-hex characters', () {
+      const fallback = Colors.red;
+      final color = "#GGHHHH".toColor(fallback: fallback);
+      expect(color, fallback);
+    });
+
+    test('should return fallback when hex length is unsupported', () {
+      const fallback = Colors.orange;
+      final color = "#FFF".toColor(fallback: fallback);
+      expect(color, fallback);
+    });
+
+    test('should return fallback for empty string', () {
+      const fallback = Colors.purple;
+      final color = "".toColor(fallback: fallback);
+      expect(color, fallback);
+    });
+
+    test('should convert lowercase hex', () {
+      final color = "#ff0000".toColor();
+      expect(color, const Color(0xFFFF0000));
+    });
+
+    test('should convert mixed-case hex', () {
+      final color = "#Ff00Ff".toColor();
+      expect(color, const Color(0xFFFf00Ff));
+    });
+  });
+}