refactoring: Class modifier changed and used flutter gen for fonts

Author: utpal-barman

lib/main_common.dart

@@ -2,10 +2,12 @@ import 'package:flutter/material.dart';
 import 'package:flutter_template/injection/dependencies.dart';
 import 'package:flutter_template/presentation/app.dart';
 import 'package:flutter_template/presentation/app_flavor.dart';
+import 'package:flutter_template/presentation/common/assets_cache_manager.dart';
 
 // ignore: avoid_void_async
 void mainCommon(AppFlavor flavor) async {
   WidgetsFlutterBinding.ensureInitialized();
   await DependencyManager.inject(flavor);
+  await AssetsCachingManager.cacheAnimationsRoot();
   runApp(const App());
 }

lib/presentation/common/assets_cache_manager.dart

@@ -0,0 +1,21 @@
+abstract interface class AssetsCachingManager {
+  /// Caches only the animations required at the initial app startup,
+  /// specifically for the splash screen.
+  ///
+  /// This method should be called before [runApp] to ensure that essential
+  /// animations are loaded early, improving the user experience during
+  /// the app's launch phase.
+  ///
+  /// By caching only necessary animations, this method reduces memory usage
+  /// and improves performance.
+  ///
+  /// Typically invoked during app initialization to enhance startup efficiency.
+  static Future<void> cacheAnimationsRoot() async {
+    // Example:
+    // try {
+    //   await AssetLottie(Assets.animations.splash.path).load();
+    // } catch (e) {
+    //   // Nothing to do
+    // }
+  }
+}

lib/presentation/resources/app_color_palette.dart

@@ -3,7 +3,7 @@ import 'package:flutter/material.dart';
 /// Defines color palette for the application.
 ///
 /// Consider using the color name that is mentioned in Figma.
-sealed class AppColorPalette {
+abstract interface class AppColorPalette {
   const AppColorPalette._();
 
   static const alpha = Colors.transparent;

lib/presentation/resources/app_fonts.dart

@@ -1,7 +1,9 @@
-sealed class AppFonts {
+import 'package:flutter_template/gen/fonts.gen.dart';
+
+abstract interface class AppFonts {
   AppFonts._();
 
-  static const roboto = 'Roboto';
+  static const roboto = FontFamily.roboto;
 
   static String get activeFontFamily => roboto;
 }

lib/presentation/resources/app_icons.dart

@@ -1,6 +1,5 @@
 import 'package:flutter/material.dart';
-import 'package:flutter_template/presentation/resources/app_colors.dart';
-import 'package:flutter_template/presentation/resources/app_fonts.dart';
+import 'package:flutter_template/presentation/resources/resources.dart';
 import 'package:theme_tailor_annotation/theme_tailor_annotation.dart';
 
 part 'app_text_styles.tailor.dart';

lib/presentation/resources/app_text_styles.dart

@@ -2,7 +2,7 @@ import 'package:flutter/material.dart';
 import 'package:flutter_template/presentation/extensions/color_extensions.dart';
 import 'package:flutter_template/presentation/resources/resources.dart';
 
-sealed class AppTheme {
+abstract interface class AppTheme {
   const AppTheme._();
 
   static ThemeData fromBrightness(Brightness brightness) {

lib/presentation/resources/app_theme.dart

@@ -4,7 +4,7 @@ import 'package:flutter/material.dart';
 ///
 /// This class contains non-sensitive information and is designed to maintain consistency
 /// across the app's UI elements.
-sealed class AppUiConstants {
+abstract interface class AppUiConstants {
   AppUiConstants._();
 
   // Animations

lib/presentation/resources/app_ui_constants.dart

@@ -1,6 +1,5 @@
 export 'package:flutter_template/presentation/resources/app_colors.dart';
 export 'package:flutter_template/presentation/resources/app_fonts.dart';
-export 'package:flutter_template/presentation/resources/app_icons.dart';
 export 'package:flutter_template/presentation/resources/app_images.dart';
 export 'package:flutter_template/presentation/resources/app_text_styles.dart';
 export 'package:flutter_template/presentation/resources/app_theme.dart';