import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:latlong2/latlong.dart';

import '../providers/current_mission_provider.dart';
import '../providers/geocoding_provider.dart';
import '../providers/map_controller_provider.dart';
import '../providers/mission_meta_provider.dart';
import '../providers/wind_provider.dart';

/// Ortssuche (Nominatim) + Home-/Fit-Buttons, eingebettet als Mittelteil
/// der Plan/Fly-Kopfleiste (HTML-Demonstrator: #searchWrap/#homeBtn/
/// #fitBtn sitzen alle in derselben Leiste wie die Modus-Buttons).
///
/// Vollstaendig selbststaendig (kein Callback-Durchreichen von aussen):
/// greift direkt auf den geteilten mapControllerProvider und
/// currentMissionProvider zu, da diese Aktionen konzeptionell zur
/// Kartensteuerung gehoeren, nicht zum Elternwidget.
class MapSearchControls extends ConsumerStatefulWidget {
  const MapSearchControls({super.key});

  @override
  ConsumerState<MapSearchControls> createState() => _MapSearchControlsState();
}

class _MapSearchControlsState extends ConsumerState<MapSearchControls> {
  final _controller = TextEditingController();

  @override
  void dispose() {
    _controller.dispose();
    super.dispose();
  }

  Future<void> _submitSearch() async {
    final query = _controller.text.trim();
    FocusScope.of(context).unfocus();
    if (query.isEmpty) return;

    final messenger = ScaffoldMessenger.of(context);
    try {
      final result = await ref.read(nominatimServiceProvider).search(query);
      if (result == null) {
        messenger.showSnackBar(const SnackBar(content: Text('Location not found')));
        return;
      }
      ref.read(mapControllerProvider).move(LatLng(result.lat, result.lon), 15);

      // Eine Ortssuche beginnt immer eine neue, nach dem Ort benannte
      // Mission statt nur die Karte zu verschieben (HTML-Demonstrator:
      // setMissionFromPlace(), aufgerufen aus doSearch()) - vorherige
      // Aenderungen werden dabei zuerst autosaved, gehen also nicht verloren.
      await ref
          .read(currentMissionMetaProvider.notifier)
          .startNewFromPlace(result.label);
      await ref.read(headerWindProvider.notifier).refresh();
    } catch (_) {
      messenger.showSnackBar(const SnackBar(content: Text('Search failed')));
    }
  }

  /// Zentriert auf den ersten Wegpunkt (HTML-Demonstrator: homeBtn).
  void _onHomePressed() {
    final waypoints = ref.read(currentMissionProvider);
    if (waypoints.isEmpty) {
      ScaffoldMessenger.of(context)
          .showSnackBar(const SnackBar(content: Text('No waypoints yet')));
      return;
    }
    final home = waypoints.first;
    ref.read(mapControllerProvider).move(LatLng(home.lat, home.lon), 16);
  }

  /// Zoomt auf die gesamte Mission (HTML-Demonstrator: fitToWaypoints()).
  void _onFitPressed() {
    final waypoints = ref.read(currentMissionProvider);
    if (waypoints.isEmpty) {
      ScaffoldMessenger.of(context)
          .showSnackBar(const SnackBar(content: Text('No waypoints to fit')));
      return;
    }
    fitMapToWaypoints(ref, waypoints);
  }

  @override
  Widget build(BuildContext context) {
    return Row(
      children: [
        Expanded(
          child: Container(
            height: 34,
            padding: const EdgeInsets.only(left: 12, right: 4),
            decoration: BoxDecoration(
              color: Colors.black.withValues(alpha: 0.55),
              borderRadius: BorderRadius.circular(17),
            ),
            child: Row(
              children: [
                Expanded(
                  child: TextField(
                    controller: _controller,
                    onSubmitted: (_) => _submitSearch(),
                    textInputAction: TextInputAction.search,
                    style: const TextStyle(color: Colors.white, fontSize: 13),
                    decoration: InputDecoration(
                      isDense: true,
                      border: InputBorder.none,
                      hintText: 'Search location',
                      hintStyle: TextStyle(
                        color: Colors.white.withValues(alpha: 0.55),
                      ),
                    ),
                  ),
                ),
                IconButton(
                  onPressed: _submitSearch,
                  icon: const Icon(Icons.search, color: Colors.white, size: 16),
                  padding: EdgeInsets.zero,
                  constraints: const BoxConstraints(minWidth: 26, minHeight: 26),
                ),
              ],
            ),
          ),
        ),
        const SizedBox(width: 8),
        _NavIconButton(icon: Icons.home, onTap: _onHomePressed),
        const SizedBox(width: 8),
        _NavIconButton(icon: Icons.crop_free, onTap: _onFitPressed),
      ],
    );
  }
}

class _NavIconButton extends StatelessWidget {
  const _NavIconButton({required this.icon, required this.onTap});

  final IconData icon;
  final VoidCallback onTap;

  @override
  Widget build(BuildContext context) {
    return GestureDetector(
      onTap: onTap,
      child: Container(
        width: 34,
        height: 34,
        decoration: BoxDecoration(
          shape: BoxShape.circle,
          color: Colors.black.withValues(alpha: 0.55),
        ),
        child: Icon(icon, color: Colors.white, size: 16),
      ),
    );
  }
}