BlockSeasons/lib/ui/screens/splash_screen.dart

import 'package:flutter/material.dart';

import 'season_title_screen.dart';

Widget _defaultNextScreen() => const SeasonTitleScreen();

/// Logo-assembly splash: four glossy blocks fly in to form a 2x2 mark, the
/// wordmark fades in, then we hand off. SaveRepository is already opened in
/// main() so this doubles as perceived-zero loading time.
class SplashScreen extends StatefulWidget {
  const SplashScreen({super.key, this.nextScreen = _defaultNextScreen});

  /// Built when the splash finishes; the season title card task repoints
  /// the default.
  final Widget Function() nextScreen;

  @override
  State<SplashScreen> createState() => _SplashScreenState();
}

class _SplashScreenState extends State<SplashScreen>
    with SingleTickerProviderStateMixin {
  late final AnimationController _c = AnimationController(
    vsync: this,
    duration: const Duration(milliseconds: 1900),
  )..addStatusListener((status) {
      if (status == AnimationStatus.completed && mounted) {
        Navigator.of(context).pushReplacement(
          MaterialPageRoute(builder: (_) => widget.nextScreen()),
        );
      }
    });

  /// (color, fly-in direction unit, 2x2 slot unit) per block.
  static const _blocks = [
    (Color(0xFFFF7EB3), Offset(-1.2, -0.4), Offset(-0.5, -0.5)),
    (Color(0xFFFFD166), Offset(1.2, -0.4), Offset(0.5, -0.5)),
    (Color(0xFF6FCDF5), Offset(-1.2, 0.6), Offset(-0.5, 0.5)),
    (Color(0xFF7EDB9C), Offset(1.2, 0.6), Offset(0.5, 0.5)),
  ];

  @override
  void initState() {
    super.initState();
    _c.forward();
  }

  @override
  void dispose() {
    _c.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    const blockSize = 46.0;
    const gap = 3.0;
    return Scaffold(
      backgroundColor: const Color(0xFF0E1430),
      body: SizedBox.expand(
        child: AnimatedBuilder(
          animation: _c,
          builder: (context, _) {
            final titleT = const Interval(0.60, 0.88, curve: Curves.easeOut)
                .transform(_c.value);
            return Stack(
              alignment: Alignment.center,
              children: [
                for (var i = 0; i < _blocks.length; i++)
                  _block(i, blockSize, gap),
                Transform.translate(
                  offset: Offset(0, 78 + 12 * (1 - titleT)),
                  child: Opacity(
                    opacity: titleT,
                    child: const Text(
                      'BLOCK SEASONS',
                      style: TextStyle(
                        fontSize: 26,
                        fontWeight: FontWeight.w900,
                        letterSpacing: 4,
                        color: Colors.white,
                      ),
                    ),
                  ),
                ),
              ],
            );
          },
        ),
      ),
    );
  }

  Widget _block(int i, double size, double gap) {
    final (color, from, to) = _blocks[i];
    final t = Interval(0.06 * i, 0.45 + 0.06 * i, curve: Curves.easeOutBack)
        .transform(_c.value);
    final begin = Offset(from.dx * 160, from.dy * 280);
    final end = Offset(to.dx * (size + gap), to.dy * (size + gap));
    final pos = Offset.lerp(begin, end, t)!;
    return Transform.translate(
      offset: pos,
      child: Container(
        width: size,
        height: size,
        decoration: BoxDecoration(
          borderRadius: BorderRadius.circular(11),
          gradient: LinearGradient(
            begin: Alignment.topLeft,
            end: Alignment.bottomRight,
            colors: [
              Color.lerp(color, Colors.white, 0.28)!,
              color,
              Color.lerp(color, Colors.black, 0.22)!,
            ],
          ),
          boxShadow: [
            BoxShadow(
              color: color.withValues(alpha: 0.55),
              blurRadius: 18,
            ),
          ],
        ),
      ),
    );
  }
}