import 'package:firebase_auth/firebase_auth.dart';
import 'package:flutter/material.dart';

import 'home_screen.dart';
import 'logged_home.dart';

final ValueNotifier<bool> forceHomeScreen = ValueNotifier<bool>(false);

class AuthGate extends StatelessWidget {
  const AuthGate({super.key});

  @override
  Widget build(BuildContext context) {
    return ValueListenableBuilder<bool>(
      valueListenable: forceHomeScreen,
      builder: (context, forcedHome, _) {
        return StreamBuilder<User?>(
          stream: FirebaseAuth.instance.authStateChanges(),
          builder: (context, snapshot) {
            final user = snapshot.data;

            final Widget child;
            if (snapshot.connectionState == ConnectionState.waiting) {
              child = const SizedBox.shrink();
            } else if (forcedHome || user == null) {
              child = const HomeScreen(key: ValueKey('home_screen'));
            } else {
              child = const LoggedHomeScreen(key: ValueKey('logged_home_screen'));
            }

            return AnimatedSwitcher(
              duration: const Duration(milliseconds: 280),
              reverseDuration: const Duration(milliseconds: 240),
              switchInCurve: Curves.easeOutCubic,
              switchOutCurve: Curves.easeInCubic,
              transitionBuilder: (child, animation) {
                final fade = CurvedAnimation(parent: animation, curve: Curves.easeOut);
                return FadeTransition(
                  opacity: fade,
                  child: ScaleTransition(
                    scale: Tween<double>(begin: 0.985, end: 1.0).animate(fade),
                    child: child,
                  ),
                );
              },
              child: child,
            );
          },
        );
      },
    );
  }
}