import 'dart:async';
import 'dart:ui';

import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:go_router/go_router.dart';

import '../../core/auth/auth_notifier.dart';
import '../../core/auth/onboarding_intent_provider.dart';
import '../../core/theme/halo_tokens.dart';

/// S1 · Splash — figma-bestie/project/screens/onboarding.jsx
///
/// Self-driving: waits for both a 1s minimum hold AND the auth provider to
/// resolve, then navigates to the appropriate destination. The router's
/// redirect leaves /splash alone — see [router.dart].
class SplashScreen extends ConsumerStatefulWidget {
  const SplashScreen({super.key});

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

class _SplashScreenState extends ConsumerState<SplashScreen> {
  bool _holdElapsed = false;
  bool _navigated = false;

  @override
  void initState() {
    super.initState();
    WidgetsBinding.instance.addPostFrameCallback((_) {
      if (!mounted) return;
      // 2.5s here because the native Android launch splash covers Flutter for
      // ~1-1.5s on cold start. By the time the user actually sees this widget,
      // ~1s has already burned — 2.5s leaves a comfortable ~1.2s of visible
      // splash before we navigate.
      Future.delayed(const Duration(milliseconds: 2500), () {
        if (!mounted) return;
        setState(() => _holdElapsed = true);
        _maybeLeave();
      });
    });
  }

  void _maybeLeave() {
    if (_navigated || !mounted || !_holdElapsed) return;
    final authState = ref.read(authProvider);
    if (authState is AsyncLoading) return;
    _navigated = true;

    final data = authState.valueOrNull;
    if (data is AuthNeedsDisplayNameData) {
      context.go('/auth/set-name');
    } else if (data is AuthForceRegisterData) {
      context.go('/auth/force-register');
    } else if (data is AuthAuthenticatedData &&
        ref.read(onboardingIntentProvider) == OnboardingIntent.onboarding) {
      context.go('/payment/entry');
    } else {
      context.go('/home');
    }
  }

  @override
  Widget build(BuildContext context) {
    ref.listen(authProvider, (_, __) => _maybeLeave());
    return Scaffold(
      body: Container(
        decoration: const BoxDecoration(
          gradient: LinearGradient(
            begin: Alignment.topCenter,
            end: Alignment.bottomCenter,
            stops: [0.0, 0.6, 1.0],
            colors: [
              HaloTokens.brandSofter,
              HaloTokens.bg,
              HaloTokens.accentSoft,
            ],
          ),
        ),
        child: Stack(
          children: [
            const Positioned(
              top: 80,
              right: -40,
              child: _Orb(
                size: 180,
                color: HaloTokens.brand,
                opacity: 0.31,
                blurSigma: 20,
              ),
            ),
            const Positioned(
              bottom: 120,
              left: -40,
              child: _Orb(
                size: 160,
                color: HaloTokens.accent,
                opacity: 0.38,
                blurSigma: 24,
              ),
            ),
            SafeArea(
              child: Padding(
                padding: const EdgeInsets.fromLTRB(28, 40, 28, 40),
                child: Center(
                  child: Column(
                    mainAxisSize: MainAxisSize.min,
                    children: [
                      Container(
                        width: 96,
                        height: 96,
                        decoration: BoxDecoration(
                          color: HaloTokens.brandLogoBg,
                          borderRadius: BorderRadius.circular(24),
                          boxShadow: HaloShadows.soft,
                        ),
                        clipBehavior: Clip.antiAlias,
                        // logo.png has ~25% internal whitespace around the
                        // glyph; scale up so the visible art reaches the edges
                        // of the tile. The Container clip keeps it inside the
                        // rounded square.
                        child: Transform.scale(
                          scale: 1.4,
                          child: Image.asset(
                            'assets/icons/logo.png',
                            fit: BoxFit.cover,
                          ),
                        ),
                      ),
                      const SizedBox(height: 28),
                      const Text(
                        'HaloBestie',
                        style: TextStyle(
                          fontFamily: HaloTokens.fontDisplay,
                          fontSize: 44,
                          fontWeight: FontWeight.w700,
                          height: 1.05,
                          letterSpacing: -1.1,
                          color: HaloTokens.brandDark,
                        ),
                      ),
                      const SizedBox(height: 18),
                      ConstrainedBox(
                        constraints: const BoxConstraints(maxWidth: 280),
                        child: const Text(
                          'kamu gak harus ngerasain\nini sendirian.',
                          textAlign: TextAlign.center,
                          style: TextStyle(
                            fontFamily: HaloTokens.fontBody,
                            fontSize: 15,
                            height: 1.5,
                            color: HaloTokens.inkSoft,
                          ),
                        ),
                      ),
                    ],
                  ),
                ),
              ),
            ),
          ],
        ),
      ),
    );
  }
}

class _Orb extends StatelessWidget {
  const _Orb({
    required this.size,
    required this.color,
    required this.opacity,
    required this.blurSigma,
  });

  final double size;
  final Color color;
  final double opacity;
  final double blurSigma;

  @override
  Widget build(BuildContext context) {
    return IgnorePointer(
      child: ImageFiltered(
        imageFilter: ImageFilter.blur(sigmaX: blurSigma, sigmaY: blurSigma),
        child: Container(
          width: size,
          height: size,
          decoration: BoxDecoration(
            shape: BoxShape.circle,
            gradient: RadialGradient(
              center: const Alignment(-0.4, -0.4),
              radius: 0.7,
              colors: [color.withValues(alpha: opacity), color.withValues(alpha: 0)],
            ),
          ),
        ),
      ),
    );
  }
}