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

import '../screens/dashboard/dashboard_screen.dart';
import '../screens/sensor_list/sensor_list_screen.dart';
import '../screens/graph/graph_screen.dart';
import '../screens/dtc/dtc_screen.dart';
import '../screens/datalog/datalog_list_screen.dart';
import '../screens/datalog/datalog_playback_bar.dart';
import '../../core/providers/datalog_provider.dart';
import '../screens/settings/settings_screen.dart';
import 'bt_status_chip.dart';
import 'data_status_banner.dart';
import 'record_fab.dart';

final _navIndexProvider = StateProvider<int>((ref) => 0);

class MainNav extends ConsumerWidget {
  const MainNav({super.key});

  static const _screens = [
    DashboardScreen(),
    SensorListScreen(),
    GraphScreen(),
    DtcScreen(),
  ];

  static const _items = [
    BottomNavigationBarItem(
      icon: Icon(Icons.speed),
      label: 'Dashboard',
    ),
    BottomNavigationBarItem(
      icon: Icon(Icons.list_alt),
      label: 'Sensors',
    ),
    BottomNavigationBarItem(
      icon: Icon(Icons.show_chart),
      label: 'Graph',
    ),
    BottomNavigationBarItem(
      icon: Icon(Icons.warning_amber_outlined),
      label: 'DTC',
    ),
  ];

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final index = ref.watch(_navIndexProvider);
    final playback = ref.watch(playbackProvider);

    return Scaffold(
      appBar: AppBar(
        title: const Text('HV BT Dashboard'),
        actions: [
          const BtStatusChip(),
          IconButton(
            icon: const Icon(Icons.folder_open_outlined),
            tooltip: 'Saved Sessions',
            onPressed: () => Navigator.push(
              context,
              MaterialPageRoute(builder: (_) => const DatalogListScreen()),
            ),
          ),
          // Record sits in the app bar so it never covers dashboard values.
          const RecordButton(),
          IconButton(
            icon: const Icon(Icons.settings_outlined),
            tooltip: 'Settings',
            onPressed: () => Navigator.push(
              context,
              MaterialPageRoute(builder: (_) => const SettingsScreen()),
            ),
          ),
        ],
      ),
      // SafeArea: in landscape the system navigation bar sits on a side.
      body: SafeArea(
        top: false,
        bottom: false,
        child: Column(
          children: [
            const DataStatusBanner(),
            if (playback.isActive) DatalogPlaybackBar(state: playback),
            Expanded(
              child: IndexedStack(
                index: index,
                children: _screens,
              ),
            ),
          ],
        ),
      ),
      bottomNavigationBar: BottomNavigationBar(
        currentIndex: index,
        items: _items,
        onTap: (i) => ref.read(_navIndexProvider.notifier).state = i,
      ),
    );
  }
}