library;

import 'dart:async';

import 'package:flutter/material.dart';
import 'package:wolf_3d_flutter/wolf_3d_flutter.dart';

/// Minimal app shell that binds a prepared [Wolf3dFlutterEngine] instance to
/// host screens.
class Wolf3dApp extends StatefulWidget {
  /// Shared initialized facade that owns game data, input, and audio services.
  final Wolf3dFlutterEngine engine;

  const Wolf3dApp({
    super.key,
    required this.engine,
  });

  @override
  State<Wolf3dApp> createState() => _Wolf3dAppState();
}

class _Wolf3dAppState extends State<Wolf3dApp> with WidgetsBindingObserver {
  Future<void>? _shutdownFuture;

  @override
  void initState() {
    super.initState();
    WidgetsBinding.instance.addObserver(this);
  }

  @override
  void dispose() {
    WidgetsBinding.instance.removeObserver(this);
    unawaited(_ensureAudioShutdown());
    super.dispose();
  }

  @override
  void didChangeAppLifecycleState(AppLifecycleState state) {
    if (state == AppLifecycleState.detached) {
      unawaited(_ensureAudioShutdown());
    }
  }

  Future<void> _ensureAudioShutdown() {
    final Future<void>? existing = _shutdownFuture;
    if (existing != null) {
      return existing;
    }

    final Future<void> shutdown = widget.engine.shutdownAudio();
    _shutdownFuture = shutdown;
    return shutdown;
  }

  @override
  Widget build(BuildContext context) {
    return widget.engine.availableGames.isEmpty
        ? NoGameDataScreen(
            configuredDataDirectory: widget.engine.configuredDataDirectory,
          )
        : GameScreen(wolf3d: widget.engine);
  }
}