/// Active gameplay screen for the Flutter host.
library;

import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:wolf_3d_dart/wolf_3d_engine.dart';
import 'package:wolf_3d_flutter/wolf_3d_flutter.dart';
import 'package:wolf_3d_renderer/wolf_3d_ascii_renderer.dart';
import 'package:wolf_3d_renderer/wolf_3d_flutter_renderer.dart';

/// Launches a [WolfEngine] via [Wolf3d] and exposes renderer/input integrations.
class GameScreen extends StatefulWidget {
  /// Shared application facade owning the engine, audio, and input.
  final Wolf3d wolf3d;

  /// Creates a gameplay screen driven by [wolf3d].
  const GameScreen({
    required this.wolf3d,
    super.key,
  });

  @override
  State<GameScreen> createState() => _GameScreenState();
}

class _GameScreenState extends State<GameScreen> {
  late final WolfEngine _engine;
  bool _useAsciiMode = false;

  @override
  void initState() {
    super.initState();
    _engine = widget.wolf3d.launchEngine(
      onGameWon: () {
        _engine.difficulty = null;
        widget.wolf3d.clearActiveDifficulty();
        Navigator.of(context).pop();
      },
    );
  }

  @override
  Widget build(BuildContext context) {
    return PopScope(
      canPop: _engine.difficulty != null,
      onPopInvokedWithResult: (didPop, _) {
        if (!didPop && _engine.difficulty == null) {
          widget.wolf3d.input.queueBackAction();
        }
      },
      child: Scaffold(
        body: LayoutBuilder(
          builder: (context, constraints) {
            return Listener(
              onPointerDown: (event) {
                widget.wolf3d.input.onPointerDown(event);
              },
              onPointerUp: widget.wolf3d.input.onPointerUp,
              onPointerMove: widget.wolf3d.input.onPointerMove,
              onPointerHover: widget.wolf3d.input.onPointerMove,
              child: Stack(
                children: [
                  // Keep both renderers behind the same engine so mode switching does
                  // not reset level state or audio playback.
                  _useAsciiMode
                      ? WolfAsciiRenderer(engine: _engine)
                      : WolfFlutterRenderer(engine: _engine),

                  if (!_engine.isInitialized)
                    Container(
                      color: Colors.black,
                      child: const Center(
                        child: Column(
                          mainAxisSize: MainAxisSize.min,
                          children: [
                            CircularProgressIndicator(color: Colors.teal),
                            SizedBox(height: 20),
                            Text(
                              "GET PSYCHED!",
                              style: TextStyle(
                                color: Colors.teal,
                                fontFamily: 'monospace',
                              ),
                            ),
                          ],
                        ),
                      ),
                    ),

                  // Tab toggles the renderer implementation for quick visual debugging.
                  Focus(
                    autofocus: true,
                    onKeyEvent: (node, event) {
                      if (event is KeyDownEvent &&
                          event.logicalKey == LogicalKeyboardKey.tab) {
                        setState(() => _useAsciiMode = !_useAsciiMode);
                        return KeyEventResult.handled;
                      }
                      return KeyEventResult.ignored;
                    },
                    child: const SizedBox.shrink(),
                  ),

                  // A second full-screen overlay keeps the presentation simple while
                  // the engine is still warming up or decoding the first frame.
                  if (!_engine.isInitialized)
                    Container(
                      color: Colors.black,
                      child: const Center(
                        child: CircularProgressIndicator(color: Colors.teal),
                      ),
                    ),

                  Positioned(
                    top: 16,
                    right: 16,
                    child: Text(
                      'TAB: Swap Renderer',
                      style: TextStyle(
                        color: Colors.white.withValues(alpha: 0.5),
                      ),
                    ),
                  ),
                ],
              ),
            );
          },
        ),
      ),
    );
  }
}