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

import '../app_mode/app_mode_cubit.dart';
import 'screens/fly/fly_screen.dart';
import 'screens/plan/plan_screen.dart';
import 'widgets/top_mode_bar.dart';

/// Haelt die persistente Kopfleiste (Plan/Fly-Umschalter) und schaltet
/// darunter zwischen Plan- und Fly-Screen um, gesteuert von der App-Mode
/// State Machine (Architektur-Doku 2.2). Connect/Upload sind
/// Uebergangszustaende innerhalb des Plan-Screens (Handover-Prozess).
class AppShell extends StatelessWidget {
  const AppShell({super.key});

  @override
  Widget build(BuildContext context) {
    final mode = context.select((AppModeCubit c) => c.state.mode);
    final screen = mode == AppMode.fly ? const FlyScreen() : const PlanScreen();

    return Scaffold(
      body: Stack(
        children: [
          Positioned.fill(child: screen),
          const Align(alignment: Alignment.topCenter, child: TopModeBar()),
        ],
      ),
    );
  }
}