import 'package:flutter/material.dart';
import 'package:geolocator/geolocator.dart';
import 'package:intaleq_maps/intaleq_maps.dart';

import '../config/app_config.dart';
import '../models/angle_unit.dart';
import '../models/landmark.dart';
import '../models/military_operations_models.dart';
import '../models/navigation_state.dart';
import '../services/military_grid_utils.dart';
import '../services/offline_los_engine.dart';
import '../services/offline_routing_engine.dart';
import '../services/resection_calculator.dart';
import '../services/tactical_api_service.dart';
import '../services/tactical_isochrone_engine.dart';
import '../services/turn_by_turn_navigation_engine.dart';
import '../services/viewshed_360_engine.dart';
import '../widgets/active_navigation_hud.dart';
import '../widgets/camera_resection_view.dart';
import '../widgets/interactive_map_picker_hud.dart';
import '../widgets/place_search_sheet.dart';
import '../widgets/tactical_artillery_sheet.dart';
import '../widgets/tactical_drawer.dart';
import '../widgets/tactical_hlz_sheet.dart';
import '../widgets/tactical_initial_provisioning_dialog.dart';
import '../widgets/tactical_isochrone_sheet.dart';
import '../widgets/tactical_los_sheet.dart';
import '../widgets/tactical_minefield_sheet.dart';
import '../widgets/tactical_overlays_sheet.dart';
import '../widgets/tactical_route_planner_sheet.dart';
import '../widgets/tactical_symbols_sheet.dart';
import '../widgets/tactical_viewshed_sheet.dart';

class TacticalMapScreen extends StatefulWidget {
  const TacticalMapScreen({super.key});

  @override
  State<TacticalMapScreen> createState() => _TacticalMapScreenState();
}

class _TacticalMapScreenState extends State<TacticalMapScreen> {
  final GlobalKey<ScaffoldState> _scaffoldKey = GlobalKey<ScaffoldState>();
  IntaleqMapController? _mapController;
  String _currentTacticalMode =
      'nav'; // 'nav', 'resection_cam', 'routing', 'los', 'viewshed_360', 'artillery', 'hlz', 'minefield', 'isochrone', 'symbols', 'overlays'
  AngleUnit _angleUnit = AngleUnit.dual;
  TacticalVehicleProfile _selectedProfile = TacticalVehicleProfile.convoy;

  // Live GPS Location
  LatLng? _currentGpsPosition;

  // Camera Center for Interactive Map Pin Picker
  LatLng _currentCameraCenter = const LatLng(31.9539, 35.9106);
  MapPickerTarget? _activePickerTarget;

  // Resection Observations & Result
  final List<ResectionObservation> _observations = [];
  ResectionResult? _resectionResult;

  // Tactical Route Plan (Hybrid: Online Server + Offline Fallback)
  OfflineRoutePlan? _activeRoute;

  // Tactical Line of Sight (LOS) State
  LatLng? _losObserver;
  LatLng? _losTarget;
  OfflineLosReport? _activeLosReport;

  // Tactical 360 Viewshed State
  Viewshed360Report? _activeViewshedReport;

  // Artillery Fire Mission State
  LatLng? _artilleryGun;
  LatLng? _artilleryTarget;
  ArtilleryFiringSolution? _activeArtillerySolution;

  // Helicopter Landing Zone State
  LatLng? _hlzCenter;
  HlzAssessmentResult? _activeHlzResult;

  // Minefield & Breaching State
  LatLng? _minefieldStart;
  LatLng? _minefieldEnd;
  MinefieldZoneResult? _activeMinefieldResult;

  // Isochrone QRF Reachability State
  LatLng? _isochroneCenter;
  List<IsochroneRing>? _activeIsochroneRings;

  // Tactical Placed Symbols
  TacticalSymbolType? _activePlacementSymbolType;
  final List<TacticalSymbolItem> _placedSymbols = [
    TacticalSymbolItem(
      id: 'sym-default-1',
      name: 'كتيبة المشاة الآلية 4',
      type: TacticalSymbolType.friendlyInfantry,
      position: const LatLng(31.9800, 35.8800),
      echelon: MilitaryEchelon.battalion,
    ),
    TacticalSymbolItem(
      id: 'sym-default-2',
      name: 'مربض مدفعية M109',
      type: TacticalSymbolType.friendlyArtillery,
      position: const LatLng(31.9300, 35.9100),
      echelon: MilitaryEchelon.battalion,
    ),
    TacticalSymbolItem(
      id: 'sym-default-3',
      name: 'رادار كشف تكتيكي',
      type: TacticalSymbolType.friendlyRadar,
      position: const LatLng(32.0200, 35.8400),
      echelon: MilitaryEchelon.company,
    ),
  ];

  // Tactical Overlays (IPB Layers)
  List<TacticalOverlayLayer> _overlayLayers = [
    TacticalOverlayLayer(
      id: 'layer_feba',
      nameAr: 'الخط الأمامي لمنطقة القتال (FEBA / FLOT)',
      color: const Color(0xFF0071E3),
      isVisible: true,
      lines: [
        [
          const LatLng(32.1000, 35.7500),
          const LatLng(32.0200, 35.8500),
          const LatLng(31.9500, 35.9000),
          const LatLng(31.8500, 35.9800),
        ]
      ],
    ),
    TacticalOverlayLayer(
      id: 'layer_mobility',
      nameAr: 'ممرات الحركة ومحاور التقدم (Mobility Corridors)',
      color: const Color(0xFF10B981),
      isVisible: true,
      lines: [
        [
          const LatLng(31.9539, 35.9106),
          const LatLng(32.0000, 35.9500),
          const LatLng(32.0500, 36.0200),
        ]
      ],
    ),
    TacticalOverlayLayer(
      id: 'layer_no_fire',
      nameAr: 'مناطق الحظر وعدم الرماية (No-Fire Areas - NFA)',
      color: const Color(0xFFEF4444),
      isVisible: false,
      polygons: [
        [
          const LatLng(31.9800, 35.9300),
          const LatLng(32.0000, 35.9300),
          const LatLng(32.0000, 35.9600),
          const LatLng(31.9800, 35.9600),
          const LatLng(31.9800, 35.9300),
        ]
      ],
    ),
  ];

  // Topographic Contours / Style Layer State
  bool _showContours = true;

  @override
  void initState() {
    super.initState();
    _initGps();
    _checkInitialProvisioning();
  }

  Future<void> _checkInitialProvisioning() async {
    final needed = await TacticalInitialProvisioningDialog.isProvisioningNeeded();
    if (needed && mounted) {
      WidgetsBinding.instance.addPostFrameCallback((_) {
        showDialog(
          context: context,
          barrierDismissible: false,
          builder: (ctx) => TacticalInitialProvisioningDialog(
            onCompleted: () {
              Navigator.pop(ctx);
              setState(() {});
            },
          ),
        );
      });
    }
  }

  Future<void> _initGps() async {
    try {
      final serviceEnabled = await Geolocator.isLocationServiceEnabled();
      if (!serviceEnabled) return;

      LocationPermission perm = await Geolocator.checkPermission();
      if (perm == LocationPermission.denied) {
        perm = await Geolocator.requestPermission();
      }
      if (perm == LocationPermission.whileInUse ||
          perm == LocationPermission.always) {
        final pos = await Geolocator.getCurrentPosition(
          locationSettings: const LocationSettings(
              accuracy: LocationAccuracy.high, timeLimit: Duration(seconds: 5)),
        );
        if (mounted) {
          setState(() {
            _currentGpsPosition = LatLng(pos.latitude, pos.longitude);
            _currentCameraCenter = _currentGpsPosition!;
          });
          _mapController?.animateCamera(
            CameraUpdate.newLatLngZoom(_currentGpsPosition!, 14.0),
          );
        }
      }
    } catch (e) {
      debugPrint('GPS init error: $e');
    }
  }

  @override
  void dispose() {
    TurnByTurnNavigationEngine.stopNavigation();
    super.dispose();
  }

  void _onObservationAdded(ResectionObservation obs) {
    setState(() {
      _observations.removeWhere((o) => o.landmark.id == obs.landmark.id);
      _observations.add(obs);
    });

    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(
        backgroundColor: const Color(0xFF0071E3),
        content: Text(
          'تم تثبيت رصد (${obs.landmark.name}) بـ ${AngleFormatter.format(obs.trueAzimuthDeg, _angleUnit)}!',
        ),
      ),
    );
  }

  void _executeResectionCalculation() {
    final result = ResectionCalculator.calculatePosition(_observations);
    if (result == null) {
      ScaffoldMessenger.of(context).showSnackBar(
        const SnackBar(
          backgroundColor: Colors.redAccent,
          content: Text(
              'خطأ: زوايا الرصد متوازية. يرجى اختيار معالم بزوايا متباعدة.'),
        ),
      );
      return;
    }

    setState(() {
      _resectionResult = result;
      _currentTacticalMode = 'nav';
    });

    final targetPos = LatLng(result.lat, result.lng);
    Future.delayed(const Duration(milliseconds: 300), () {
      if (mounted && _mapController != null) {
        _mapController!.animateCamera(
          CameraUpdate.newLatLngZoom(targetPos, 15.0),
        );
      }
    });

    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(
        backgroundColor: const Color(0xFF22C55E),
        duration: const Duration(seconds: 4),
        content: Row(
          children: [
            const Icon(Icons.gps_fixed, color: Colors.white, size: 20),
            const SizedBox(width: 10),
            Expanded(
              child: Text(
                'تم استخراج موقعك بنجاح: ${result.lat.toStringAsFixed(5)}, ${result.lng.toStringAsFixed(5)} • دقة ±${result.estimatedAccuracyMeters.round()}م',
                style:
                    const TextStyle(fontWeight: FontWeight.bold, fontSize: 12),
              ),
            ),
          ],
        ),
      ),
    );
  }

  void _openRoutePlanner({LatLng? initialOrigin, LatLng? initialDestination}) {
    showModalBottomSheet(
      context: context,
      isScrollControlled: true,
      backgroundColor: Colors.transparent,
      builder: (ctx) => TacticalRoutePlannerSheet(
        currentGps: _currentGpsPosition ?? const LatLng(31.9539, 35.9106),
        resectionFix: _resectionResult != null
            ? LatLng(_resectionResult!.lat, _resectionResult!.lng)
            : null,
        initialOrigin: initialOrigin,
        initialDestination: initialDestination,
        onRouteConfirmed: (origin, destination, profile, autoStartNav) {
          _calculateHybridRoute(
            customOrigin: origin,
            customDestination: destination,
            selectedProfile: profile,
            autoStartNav: autoStartNav,
          );
        },
        onPickOriginOnMap: () {
          setState(() => _activePickerTarget = MapPickerTarget.routeOrigin);
        },
        onPickDestinationOnMap: () {
          setState(
              () => _activePickerTarget = MapPickerTarget.routeDestination);
        },
        onClose: () => Navigator.pop(ctx),
      ),
    );
  }

  void _onConfirmPicker(MapPickerTarget target, LatLng selectedPos) {
    setState(() {
      _activePickerTarget = null;
      if (target == MapPickerTarget.losObserver) {
        _losObserver = selectedPos;
      } else if (target == MapPickerTarget.losTarget) {
        _losTarget = selectedPos;
      } else if (target == MapPickerTarget.artilleryGun) {
        _artilleryGun = selectedPos;
      } else if (target == MapPickerTarget.artilleryTarget) {
        _artilleryTarget = selectedPos;
      } else if (target == MapPickerTarget.hlzCenter) {
        _hlzCenter = selectedPos;
      } else if (target == MapPickerTarget.minefieldStart) {
        _minefieldStart = selectedPos;
      } else if (target == MapPickerTarget.minefieldEnd) {
        _minefieldEnd = selectedPos;
      } else if (target == MapPickerTarget.isochroneCenter) {
        _isochroneCenter = selectedPos;
      } else if (target == MapPickerTarget.viewshedCenter) {
        _losObserver = selectedPos;
      }
    });

    if (target == MapPickerTarget.losObserver ||
        target == MapPickerTarget.losTarget) {
      _openLosSheet();
    } else if (target == MapPickerTarget.viewshedCenter) {
      _openViewshed360Sheet();
    } else if (target == MapPickerTarget.routeOrigin ||
        target == MapPickerTarget.routeDestination) {
      _openRoutePlanner();
    } else if (target == MapPickerTarget.artilleryGun ||
        target == MapPickerTarget.artilleryTarget) {
      _openArtillerySheet();
    } else if (target == MapPickerTarget.hlzCenter) {
      _openHlzSheet();
    } else if (target == MapPickerTarget.minefieldStart ||
        target == MapPickerTarget.minefieldEnd) {
      _openMinefieldSheet();
    } else if (target == MapPickerTarget.isochroneCenter) {
      _openIsochroneSheet();
    }
  }

  void _onCancelPicker() {
    final target = _activePickerTarget;
    setState(() => _activePickerTarget = null);

    if (target == MapPickerTarget.losObserver ||
        target == MapPickerTarget.losTarget) {
      _openLosSheet();
    } else if (target == MapPickerTarget.viewshedCenter) {
      _openViewshed360Sheet();
    } else if (target == MapPickerTarget.routeOrigin ||
        target == MapPickerTarget.routeDestination) {
      _openRoutePlanner();
    } else if (target == MapPickerTarget.artilleryGun ||
        target == MapPickerTarget.artilleryTarget) {
      _openArtillerySheet();
    } else if (target == MapPickerTarget.hlzCenter) {
      _openHlzSheet();
    } else if (target == MapPickerTarget.minefieldStart ||
        target == MapPickerTarget.minefieldEnd) {
      _openMinefieldSheet();
    } else if (target == MapPickerTarget.isochroneCenter) {
      _openIsochroneSheet();
    }
  }

  void _resetResection() {
    TurnByTurnNavigationEngine.stopNavigation();
    setState(() {
      _observations.clear();
      _resectionResult = null;
      _activeRoute = null;
      _losObserver = null;
      _losTarget = null;
      _activeLosReport = null;
      _activeArtillerySolution = null;
      _activeHlzResult = null;
      _activeMinefieldResult = null;
      _activeIsochroneRings = null;
      _currentTacticalMode = 'nav';
    });
  }

  // ── Operations Modal Launchers ─────────────────────────────

  void _openLosSheet() {
    if (_losObserver == null || _losTarget == null) return;

    final initialLos = OfflineLosEngine.calculate(
      observer: _losObserver!,
      target: _losTarget!,
    );
    setState(() {
      _activeLosReport = initialLos;
    });

    showModalBottomSheet(
      context: context,
      isScrollControlled: true,
      backgroundColor: Colors.transparent,
      builder: (ctx) => TacticalLosSheet(
        observer: _losObserver!,
        target: _losTarget!,
        currentGps: _currentGpsPosition,
        angleUnit: _angleUnit,
        onUpdateLocations: (newObs, newTgt) {
          setState(() {
            _losObserver = newObs;
            _losTarget = newTgt;
          });
          final updatedLos = OfflineLosEngine.calculate(
            observer: newObs,
            target: newTgt,
          );
          setState(() {
            _activeLosReport = updatedLos;
          });
          _fitRouteBounds([newObs, newTgt]);
        },
        onVisibilityChanged: (_) {},
        onReportGenerated: (report) {
          if (mounted) {
            setState(() {
              _activeLosReport = report;
            });
          }
        },
        onPickObserverOnMap: () {
          Navigator.pop(context);
          setState(() => _activePickerTarget = MapPickerTarget.losObserver);
        },
        onPickTargetOnMap: () {
          Navigator.pop(context);
          setState(() => _activePickerTarget = MapPickerTarget.losTarget);
        },
        onClose: () {
          Navigator.pop(context);
          setState(() => _currentTacticalMode = 'nav');
        },
      ),
    );
  }

  void _openViewshed360Sheet() {
    if (_losObserver == null) return;

    final initialReport = Viewshed360Engine.calculate(
      observer: _losObserver!,
      radiusMeters: 5000.0,
      observerHeightM: 2.0,
      rayCount: 360,
    );
    setState(() {
      _activeViewshedReport = initialReport;
    });

    showModalBottomSheet(
      context: context,
      isScrollControlled: true,
      backgroundColor: Colors.transparent,
      builder: (ctx) => TacticalViewshedSheet(
        observer: _losObserver!,
        currentGps: _currentGpsPosition,
        onUpdateObserver: (newObs) {
          setState(() => _losObserver = newObs);
        },
        onReportUpdated: (rep) {
          if (mounted) {
            setState(() => _activeViewshedReport = rep);
          }
        },
        onPickObserverOnMap: () {
          Navigator.pop(context);
          setState(() => _activePickerTarget = MapPickerTarget.viewshedCenter);
        },
        onClose: () => Navigator.pop(context),
      ),
    );
  }

  void _openArtillerySheet() {
    showModalBottomSheet(
      context: context,
      isScrollControlled: true,
      backgroundColor: Colors.transparent,
      builder: (ctx) => TacticalArtillerySheet(
        gunPosition: _artilleryGun ?? _currentGpsPosition ?? const LatLng(31.9539, 35.9106),
        targetPosition: _artilleryTarget,
        angleUnit: _angleUnit,
        onPickGun: () {
          Navigator.pop(context);
          setState(() => _activePickerTarget = MapPickerTarget.artilleryGun);
        },
        onPickTarget: () {
          Navigator.pop(context);
          setState(() => _activePickerTarget = MapPickerTarget.artilleryTarget);
        },
        onSwap: () {
          setState(() {
            final temp = _artilleryGun;
            _artilleryGun = _artilleryTarget;
            _artilleryTarget = temp;
          });
        },
        onSolutionCalculated: (sol) {
          setState(() => _activeArtillerySolution = sol);
          _fitRouteBounds([sol.gunPosition, sol.targetPosition]);
        },
        onClose: () => Navigator.pop(context),
      ),
    );
  }

  void _openHlzSheet() {
    showModalBottomSheet(
      context: context,
      isScrollControlled: true,
      backgroundColor: Colors.transparent,
      builder: (ctx) => TacticalHlzSheet(
        selectedPosition: _hlzCenter ?? _currentGpsPosition ?? const LatLng(31.9539, 35.9106),
        onPickLocation: () {
          Navigator.pop(context);
          setState(() => _activePickerTarget = MapPickerTarget.hlzCenter);
        },
        onAssessmentCompleted: (res) {
          setState(() => _activeHlzResult = res);
        },
        onClose: () => Navigator.pop(context),
      ),
    );
  }

  void _openMinefieldSheet() {
    showModalBottomSheet(
      context: context,
      isScrollControlled: true,
      backgroundColor: Colors.transparent,
      builder: (ctx) => TacticalMinefieldSheet(
        startPoint: _minefieldStart ?? _currentGpsPosition ?? const LatLng(31.9539, 35.9106),
        endPoint: _minefieldEnd,
        onPickStart: () {
          Navigator.pop(context);
          setState(() => _activePickerTarget = MapPickerTarget.minefieldStart);
        },
        onPickEnd: () {
          Navigator.pop(context);
          setState(() => _activePickerTarget = MapPickerTarget.minefieldEnd);
        },
        onSwap: () {
          setState(() {
            final temp = _minefieldStart;
            _minefieldStart = _minefieldEnd;
            _minefieldEnd = temp;
          });
        },
        onZoneCalculated: (res) {
          setState(() => _activeMinefieldResult = res);
          _fitRouteBounds([res.startPoint, res.endPoint]);
        },
        onClose: () => Navigator.pop(context),
      ),
    );
  }

  void _openIsochroneSheet() {
    showModalBottomSheet(
      context: context,
      isScrollControlled: true,
      backgroundColor: Colors.transparent,
      builder: (ctx) => TacticalIsochroneSheet(
        center: _isochroneCenter ?? _currentGpsPosition ?? const LatLng(31.9539, 35.9106),
        onPickCenter: () {
          Navigator.pop(context);
          setState(() => _activePickerTarget = MapPickerTarget.isochroneCenter);
        },
        onIsochronesCalculated: (rings) {
          setState(() => _activeIsochroneRings = rings);
        },
        onClose: () => Navigator.pop(context),
      ),
    );
  }

  void _openSymbolsSheet() {
    showModalBottomSheet(
      context: context,
      isScrollControlled: true,
      backgroundColor: Colors.transparent,
      builder: (ctx) => TacticalSymbolsSheet(
        activePlacementType: _activePlacementSymbolType,
        placedSymbols: _placedSymbols,
        onSelectSymbolType: (type) {
          setState(() => _activePlacementSymbolType = type);
          Navigator.pop(context);
          ScaffoldMessenger.of(context).showSnackBar(
            SnackBar(
              backgroundColor: const Color(0xFF0071E3),
              duration: const Duration(seconds: 4),
              content: const Row(
                children: [
                  Icon(Icons.touch_app, color: Colors.white, size: 18),
                  SizedBox(width: 10),
                  Expanded(
                    child: Text(
                      'انقر على الخريطة لتثبيت الرمز العسكري في الميدان 📍',
                      style: TextStyle(fontWeight: FontWeight.bold),
                    ),
                  ),
                ],
              ),
            ),
          );
        },
        onDeleteSymbol: (s) {
          setState(() => _placedSymbols.removeWhere((item) => item.id == s.id));
        },
        onClose: () => Navigator.pop(context),
      ),
    );
  }

  void _openOverlaysSheet() {
    showModalBottomSheet(
      context: context,
      isScrollControlled: true,
      backgroundColor: Colors.transparent,
      builder: (ctx) => TacticalOverlaysSheet(
        layers: _overlayLayers,
        onToggleLayer: (layerId, isVisible) {
          setState(() {
            _overlayLayers = _overlayLayers.map((l) {
              if (l.id == layerId) return l.copyWith(isVisible: isVisible);
              return l;
            }).toList();
          });
        },
        onClose: () => Navigator.pop(context),
      ),
    );
  }

  void _handleMapTap(LatLng point) {
    // 1. Check Active Placement of Tactical Symbol
    if (_activePlacementSymbolType != null) {
      final type = _activePlacementSymbolType!;
      setState(() {
        _placedSymbols.add(TacticalSymbolItem(
          id: 'sym_${DateTime.now().millisecondsSinceEpoch}',
          name: 'وحدة ميدانية ${_placedSymbols.length + 1}',
          type: type,
          position: point,
        ));
        _activePlacementSymbolType = null;
      });
      ScaffoldMessenger.of(context).showSnackBar(
        const SnackBar(
          backgroundColor: Color(0xFF22C55E),
          content: Text('تم تثبيت الرمز العسكري على الخريطة بنجاح ✅'),
        ),
      );
      return;
    }

    // 2. Check Active Picker
    if (_activePickerTarget != null) {
      _onConfirmPicker(_activePickerTarget!, point);
      return;
    }

    // 3. Mode handlers
    if (_currentTacticalMode == 'viewshed_360') {
      setState(() => _losObserver = point);
      _openViewshed360Sheet();
      return;
    }

    if (_currentTacticalMode == 'artillery') {
      if (_artilleryGun == null) {
        setState(() => _artilleryGun = point);
      } else {
        setState(() => _artilleryTarget = point);
      }
      _openArtillerySheet();
      return;
    }

    if (_currentTacticalMode == 'hlz') {
      setState(() => _hlzCenter = point);
      _openHlzSheet();
      return;
    }

    if (_currentTacticalMode == 'minefield') {
      if (_minefieldStart == null) {
        setState(() => _minefieldStart = point);
      } else {
        setState(() => _minefieldEnd = point);
      }
      _openMinefieldSheet();
      return;
    }

    if (_currentTacticalMode == 'isochrone') {
      setState(() => _isochroneCenter = point);
      _openIsochroneSheet();
      return;
    }

    if (_currentTacticalMode == 'los') {
      if (_losObserver == null) {
        setState(() => _losObserver = point);
      } else {
        setState(() => _losTarget = point);
        _openLosSheet();
      }
      return;
    }

    // Default Tap Info
    final mil = MilitaryGridUtils.fromLatLng(point);
    final elev = JordanDemSurface.elevationAt(point.latitude, point.longitude);
    ScaffoldMessenger.of(context).hideCurrentSnackBar();
    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(
        duration: const Duration(seconds: 3),
        backgroundColor: const Color(0xFF0F172A),
        content: Row(
          children: [
            const Icon(Icons.location_searching, size: 16, color: Color(0xFF38BDF8)),
            const SizedBox(width: 8),
            Expanded(
              child: Text(
                '${mil.arabicFullFormat} • منسوب: ${elev.round()}م',
                style: const TextStyle(
                  color: Colors.white,
                  fontSize: 11.5,
                  fontWeight: FontWeight.bold,
                ),
              ),
            ),
          ],
        ),
      ),
    );
  }

  void _fitRouteBounds(List<LatLng> points) {
    if (points.isEmpty || _mapController == null) return;

    double minLat = points.first.latitude;
    double maxLat = points.first.latitude;
    double minLng = points.first.longitude;
    double maxLng = points.first.longitude;

    for (final p in points) {
      if (p.latitude < minLat) minLat = p.latitude;
      if (p.latitude > maxLat) maxLat = p.latitude;
      if (p.longitude < minLng) minLng = p.longitude;
      if (p.longitude > maxLng) maxLng = p.longitude;
    }

    final bounds = LatLngBounds(
      southwest: LatLng(minLat, minLng),
      northeast: LatLng(maxLat, maxLng),
    );

    _mapController?.animateCamera(
      CameraUpdate.newLatLngBounds(
        bounds,
        left: 40.0,
        top: 60.0,
        right: 40.0,
        bottom: 120.0,
      ),
    );
  }

  Future<void> _calculateHybridRoute({
    LatLng? customOrigin,
    LatLng? customDestination,
    TacticalVehicleProfile? selectedProfile,
    bool autoStartNav = false,
  }) async {
    final profile = selectedProfile ?? _selectedProfile;
    setState(() => _selectedProfile = profile);

    final startPoint = customOrigin ??
        _currentGpsPosition ??
        (_resectionResult != null
            ? LatLng(_resectionResult!.lat, _resectionResult!.lng)
            : const LatLng(31.9539, 35.9106));

    final targetPoint = customDestination ??
        (_observations.isNotEmpty
            ? LatLng(_observations.first.landmark.lat, _observations.first.landmark.lng)
            : LatLng(startPoint.latitude + 0.05, startPoint.longitude + 0.05));

    OfflineRoutePlan? plan;

    // 1. Try Online NestJS Server Routing API
    try {
      final serverRoute = await TacticalApiService.calculateTacticalRoute(
        origin: startPoint,
        destination: targetPoint,
        profile: profile.name,
      );

      if (serverRoute != null && serverRoute.points.isNotEmpty) {
        plan = OfflineRoutePlan(
          polylinePoints: serverRoute.points,
          totalDistanceKm: serverRoute.distanceKm,
          estimatedDurationMinutes: serverRoute.durationMinutes,
          profile: profile,
          tacticalWaypoints: const ['موقع الانطلاق', 'الهدف التكتيكي المحدد'],
          isOffline: false,
        );
      }
    } catch (e) {
      debugPrint('Online server route fallback: $e');
    }

    // 2. Fallback to 100% Sovereign On-Device Offline Routing Engine
    plan ??= OfflineRoutingEngine.calculateOnDeviceRoute(
      start: startPoint,
      destination: targetPoint,
      profile: profile,
    );

    setState(() {
      _activeRoute = plan;
      _currentTacticalMode = 'routing';
    });

    _fitRouteBounds(plan.polylinePoints);

    if (autoStartNav) {
      TurnByTurnNavigationEngine.startNavigation(
        plan: plan,
        simulate: false,
        controller: _mapController,
      );
    }
  }

  void _openPlaceSearch() {
    showModalBottomSheet(
      context: context,
      isScrollControlled: true,
      backgroundColor: Colors.transparent,
      builder: (ctx) => PlaceSearchSheet(
        onDestinationSelected: (landmark, startNav) {
          final dest = LatLng(landmark.lat, landmark.lng);
          _calculateHybridRoute(
            customDestination: dest,
            autoStartNav: startNav,
          );
        },
      ),
    );
  }

  // ── Build Declarative Overlays for Map ─────────────────────

  Set<Marker> _buildMarkers(ActiveNavigationState navState) {
    final markers = <Marker>{};

    // 1. Landmark markers
    for (final obs in _observations) {
      markers.add(
        Marker(
          markerId: MarkerId(obs.landmark.id),
          position: LatLng(obs.landmark.lat, obs.landmark.lng),
          icon: InlqBitmap.defaultMarkerWithHue(InlqBitmap.hueAzure),
          infoWindow: InfoWindow(
            title: obs.landmark.name,
            snippet: AngleFormatter.format(obs.trueAzimuthDeg, _angleUnit),
          ),
        ),
      );
    }

    // 2. Resection Fix Marker
    if (_resectionResult != null && !navState.isNavigating) {
      markers.add(
        Marker(
          markerId: const MarkerId('observer_calculated_position'),
          position: LatLng(_resectionResult!.lat, _resectionResult!.lng),
          icon: InlqBitmap.defaultMarkerWithHue(InlqBitmap.hueGreen),
          infoWindow: const InfoWindow(
            title: 'موقع الراصد المحسوب (GPS-Denied Fix)',
            snippet: 'تم استخراج الموقع بالتقاطع البصري العكسي',
          ),
        ),
      );
    }

    // 3. Routing Destination Marker
    if (_activeRoute != null && _activeRoute!.polylinePoints.isNotEmpty) {
      markers.add(
        Marker(
          markerId: const MarkerId('convoy_destination'),
          position: _activeRoute!.polylinePoints.last,
          icon: InlqBitmap.defaultMarkerWithHue(InlqBitmap.hueRed),
          infoWindow: const InfoWindow(
            title: 'الهدف التكتيكي (Objective)',
            snippet: 'نقطة الوصول المحددة',
          ),
        ),
      );
    }

    // 4. Moving Vehicle Marker
    if (navState.isNavigating && navState.currentPosition != null) {
      markers.add(
        Marker(
          markerId: const MarkerId('active_vehicle_position'),
          position: navState.currentPosition!,
          icon: InlqBitmap.defaultMarkerWithHue(InlqBitmap.hueCyan),
          infoWindow: InfoWindow(
            title: 'مركبة العمليات الميدانية',
            snippet: '${navState.currentSpeedKmH.round()} كم/س • سمت ${navState.currentHeadingDeg.round()}°',
          ),
        ),
      );
    }

    // 5. Tactical Placed Symbols
    for (final sym in _placedSymbols) {
      markers.add(
        Marker(
          markerId: MarkerId(sym.id),
          position: sym.position,
          icon: InlqBitmap.defaultMarkerWithHue(
            sym.isEnemy ? InlqBitmap.hueRed : InlqBitmap.hueBlue,
          ),
          infoWindow: InfoWindow(
            title: sym.name,
            snippet: MilitaryGridUtils.latLngToMgrs(sym.position.latitude, sym.position.longitude),
          ),
        ),
      );
    }

    // 6. Artillery Gun & Target Markers
    if (_currentTacticalMode == 'artillery') {
      if (_artilleryGun != null) {
        markers.add(
          Marker(
            markerId: const MarkerId('artillery_gun_marker'),
            position: _artilleryGun!,
            icon: InlqBitmap.defaultMarkerWithHue(InlqBitmap.hueBlue),
            infoWindow: const InfoWindow(title: '🎯 مربض المدفعية'),
          ),
        );
      }
      if (_artilleryTarget != null) {
        markers.add(
          Marker(
            markerId: const MarkerId('artillery_target_marker'),
            position: _artilleryTarget!,
            icon: InlqBitmap.defaultMarkerWithHue(InlqBitmap.hueRed),
            infoWindow: const InfoWindow(title: '💥 الهدف المعادي'),
          ),
        );
      }
    }

    // 7. HLZ Center Marker
    if (_currentTacticalMode == 'hlz' && _hlzCenter != null) {
      markers.add(
        Marker(
          markerId: const MarkerId('hlz_center_marker'),
          position: _hlzCenter!,
          icon: InlqBitmap.defaultMarkerWithHue(InlqBitmap.hueGreen),
          infoWindow: const InfoWindow(title: '🚁 مهبط الطيران العامودي (HLZ)'),
        ),
      );
    }

    return markers;
  }

  Set<Polyline> _buildPolylines(ActiveNavigationState navState) {
    final polylines = <Polyline>{};

    // 1. Tactical Line of Sight (LOS)
    if (_currentTacticalMode == 'los' && _losObserver != null && _losTarget != null) {
      if (_activeLosReport != null && _activeLosReport!.profile.length > 1) {
        final visSegments = _activeLosReport!.visibleSegments;
        for (int i = 0; i < visSegments.length; i++) {
          polylines.add(
            Polyline(
              polylineId: PolylineId('tactical_los_vis_$i'),
              points: visSegments[i],
              color: const Color(0xFF22C55E),
              width: 5.0,
            ),
          );
        }

        final blkSegments = _activeLosReport!.blockedSegments;
        for (int i = 0; i < blkSegments.length; i++) {
          polylines.add(
            Polyline(
              polylineId: PolylineId('tactical_los_blk_$i'),
              points: blkSegments[i],
              color: const Color(0xFFEF4444),
              width: 5.0,
            ),
          );
        }
      }
    }

    // 2. Artillery Ballistic Arc Ground Track
    if (_currentTacticalMode == 'artillery' && _activeArtillerySolution != null) {
      final points = _activeArtillerySolution!.trajectoryProfile.map((p) => p.coordinate).toList();
      polylines.add(
        Polyline(
          polylineId: const PolylineId('artillery_trajectory_track'),
          points: points,
          color: _activeArtillerySolution!.isCrestClear
              ? const Color(0xFF00F0FF)
              : const Color(0xFFEF4444),
          width: 4.5,
        ),
      );
    }

    // 3. Minefield Safe Breaching Lane Centerline
    if (_currentTacticalMode == 'minefield' && _activeMinefieldResult != null) {
      polylines.add(
        Polyline(
          polylineId: const PolylineId('minefield_breach_centerline'),
          points: _activeMinefieldResult!.breachLaneCenterline,
          color: const Color(0xFF10B981),
          width: 4.0,
        ),
      );
    }

    // 4. Tactical Overlays Lines
    for (final layer in _overlayLayers) {
      if (layer.isVisible) {
        for (int i = 0; i < layer.lines.length; i++) {
          polylines.add(
            Polyline(
              polylineId: PolylineId('overlay_${layer.id}_line_$i'),
              points: layer.lines[i],
              color: layer.color,
              width: 4.0,
            ),
          );
        }
      }
    }

    // 5. Active Route Polyline
    if (_activeRoute != null && _activeRoute!.polylinePoints.isNotEmpty) {
      polylines.add(
        Polyline(
          polylineId: const PolylineId('tactical_on_device_route'),
          points: _activeRoute!.polylinePoints,
          color: navState.isNavigating ? const Color(0xFF00F0FF) : const Color(0xFF38BDF8),
          width: navState.isNavigating ? 6.5 : 5.0,
        ),
      );
    }

    return polylines;
  }

  Set<Polygon> _buildPolygons() {
    final polygons = <Polygon>{};

    // 1. 360 Viewshed Radar Visible Polygon Fill
    if (_currentTacticalMode == 'viewshed_360' &&
        _activeViewshedReport != null &&
        _activeViewshedReport!.polygonVertices.isNotEmpty) {
      polygons.add(
        Polygon(
          polygonId: const PolygonId('viewshed_360_fill'),
          points: _activeViewshedReport!.polygonVertices,
          fillColor: const Color(0x4422C55E),
          strokeColor: const Color(0xFF22C55E),
          strokeWidth: 2,
        ),
      );
    }

    // 2. HLZ Pad Boundary & Approach Corridor
    if (_currentTacticalMode == 'hlz' && _activeHlzResult != null) {
      polygons.add(
        Polygon(
          polygonId: const PolygonId('hlz_pad_boundary'),
          points: _activeHlzResult!.padBoundary,
          fillColor: _activeHlzResult!.gradeColor.withAlpha(50),
          strokeColor: _activeHlzResult!.gradeColor,
          strokeWidth: 2,
        ),
      );

      polygons.add(
        Polygon(
          polygonId: const PolygonId('hlz_approach_corridor'),
          points: _activeHlzResult!.approachFunnel,
          fillColor: const Color(0x3338BDF8),
          strokeColor: const Color(0xFF38BDF8),
          strokeWidth: 1.5,
        ),
      );
    }

    // 3. Minefield Boundary & Safe Breaching Lane
    if (_currentTacticalMode == 'minefield' && _activeMinefieldResult != null) {
      polygons.add(
        Polygon(
          polygonId: const PolygonId('minefield_threat_boundary'),
          points: _activeMinefieldResult!.boundaryPolygon,
          fillColor: const Color(0x44EF4444),
          strokeColor: const Color(0xFFEF4444),
          strokeWidth: 2,
        ),
      );

      polygons.add(
        Polygon(
          polygonId: const PolygonId('minefield_safe_breach_polygon'),
          points: _activeMinefieldResult!.breachLanePolygon,
          fillColor: const Color(0x6610B981),
          strokeColor: const Color(0xFF10B981),
          strokeWidth: 2,
        ),
      );
    }

    // 4. Isochrone Response Time Rings
    if (_currentTacticalMode == 'isochrone' && _activeIsochroneRings != null) {
      for (int i = 0; i < _activeIsochroneRings!.length; i++) {
        final ring = _activeIsochroneRings![i];
        polygons.add(
          Polygon(
            polygonId: PolygonId('isochrone_ring_$i'),
            points: ring.polygonCoordinates,
            fillColor: ring.ringColor.withAlpha(30),
            strokeColor: ring.ringColor,
            strokeWidth: 2,
          ),
        );
      }
    }

    // 5. Tactical Overlays Polygons
    for (final layer in _overlayLayers) {
      if (layer.isVisible) {
        for (int i = 0; i < layer.polygons.length; i++) {
          polygons.add(
            Polygon(
              polygonId: PolygonId('overlay_${layer.id}_poly_$i'),
              points: layer.polygons[i],
              fillColor: layer.color.withAlpha(40),
              strokeColor: layer.color,
              strokeWidth: 2,
            ),
          );
        }
      }
    }

    return polygons;
  }

  @override
  Widget build(BuildContext context) {
    return ValueListenableBuilder<ActiveNavigationState>(
      valueListenable: TurnByTurnNavigationEngine.navigationState,
      builder: (context, navState, _) {
        final markers = _buildMarkers(navState);
        final polylines = _buildPolylines(navState);
        final polygons = _buildPolygons();

        return Scaffold(
          key: _scaffoldKey,
          drawer: TacticalDrawer(
            currentAngleUnit: _angleUnit,
            onAngleUnitChanged: (unit) => setState(() => _angleUnit = unit),
            onOpenResectionHud: () => setState(() => _currentTacticalMode = 'resection_cam'),
            onStartRoutingMode: () => _openRoutePlanner(),
            onStartLosMode: () {
              setState(() => _currentTacticalMode = 'los');
              _openLosSheet();
            },
            onStartViewshedMode: () {
              setState(() => _currentTacticalMode = 'viewshed_360');
              _openViewshed360Sheet();
            },
            onStartArtilleryMode: () {
              setState(() => _currentTacticalMode = 'artillery');
              _openArtillerySheet();
            },
            onStartHlzMode: () {
              setState(() => _currentTacticalMode = 'hlz');
              _openHlzSheet();
            },
            onStartMinefieldMode: () {
              setState(() => _currentTacticalMode = 'minefield');
              _openMinefieldSheet();
            },
            onStartIsochroneMode: () {
              setState(() => _currentTacticalMode = 'isochrone');
              _openIsochroneSheet();
            },
            onStartSymbolsMode: () {
              setState(() => _currentTacticalMode = 'symbols');
              _openSymbolsSheet();
            },
            onStartOverlaysMode: () {
              setState(() => _currentTacticalMode = 'overlays');
              _openOverlaysSheet();
            },
            onLandmarksSynced: () => setState(() {}),
            showContours: _showContours,
            onToggleContours: (v) => setState(() => _showContours = v),
          ),
          body: Stack(
            children: [
              // ── Map Canvas ─────────────────────────────────────────
              IntaleqMap(
                apiKey: AppConfig.apiKey,
                initialCameraPosition: CameraPosition(
                  target: _currentCameraCenter,
                  zoom: 13.0,
                ),
                styleUrl: _showContours
                    ? 'assets/style_dark.json'
                    : 'assets/style.json',
                onMapCreated: (ctrl) {
                  _mapController = ctrl;
                },
                onCameraMove: (pos) {
                  _currentCameraCenter = pos.target;
                },
                onTap: _handleMapTap,
                markers: markers,
                polylines: polylines,
                polygons: polygons,
              ),

              // ── Top Tactical Operations Bar ────────────────────────
              Positioned(
                top: 48,
                left: 16,
                right: 16,
                child: Row(
                  children: [
                    Container(
                      decoration: BoxDecoration(
                        color: const Color(0xFF090E17).withAlpha(220),
                        borderRadius: BorderRadius.circular(12),
                        border: Border.all(color: const Color(0xFF0071E3).withAlpha(120)),
                      ),
                      child: IconButton(
                        icon: const Icon(Icons.menu, color: Color(0xFF38BDF8)),
                        onPressed: () => _scaffoldKey.currentState?.openDrawer(),
                      ),
                    ),
                    const SizedBox(width: 8),
                    Expanded(
                      child: Container(
                        height: 48,
                        padding: const EdgeInsets.symmetric(horizontal: 14),
                        decoration: BoxDecoration(
                          color: const Color(0xFF090E17).withAlpha(220),
                          borderRadius: BorderRadius.circular(12),
                          border: Border.all(color: Colors.white12),
                        ),
                        child: Row(
                          children: [
                            const Icon(Icons.shield, color: Color(0xFF0071E3), size: 20),
                            const SizedBox(width: 8),
                            Text(
                              _getModeTitle(),
                              style: const TextStyle(
                                color: Colors.white,
                                fontSize: 13,
                                fontWeight: FontWeight.bold,
                              ),
                            ),
                          ],
                        ),
                      ),
                    ),
                    const SizedBox(width: 8),
                    Container(
                      decoration: BoxDecoration(
                        color: const Color(0xFF090E17).withAlpha(220),
                        borderRadius: BorderRadius.circular(12),
                        border: Border.all(color: Colors.white12),
                      ),
                      child: IconButton(
                        icon: const Icon(Icons.search, color: Color(0xFF38BDF8)),
                        onPressed: _openPlaceSearch,
                      ),
                    ),
                  ],
                ),
              ),

              // ── Interactive Pin Picker HUD ────────────────────────
              if (_activePickerTarget != null)
                InteractiveMapPickerHud(
                  target: _activePickerTarget!,
                  centerPosition: _currentCameraCenter,
                  onConfirm: () => _onConfirmPicker(_activePickerTarget!, _currentCameraCenter),
                  onCancel: _onCancelPicker,
                ),

              // ── Resection Camera Overlay ───────────────────────────
              if (_currentTacticalMode == 'resection_cam')
                CameraResectionView(
                  observations: _observations,
                  angleUnit: _angleUnit,
                  onObservationAdded: _onObservationAdded,
                  onCalculatePressed: _executeResectionCalculation,
                  onResetPressed: _resetResection,
                  onClose: () => setState(() => _currentTacticalMode = 'nav'),
                ),

              // ── Active Turn-by-Turn Navigation HUD ─────────────────
              if (navState.isNavigating)
                Positioned(
                  top: 48,
                  left: 16,
                  right: 16,
                  child: ActiveNavigationHud(
                    state: navState,
                    angleUnit: _angleUnit,
                    onStopNavigation: () {
                      TurnByTurnNavigationEngine.stopNavigation();
                    },
                  ),
                ),
            ],
          ),
        );
      },
    );
  }

  String _getModeTitle() {
    switch (_currentTacticalMode) {
      case 'los':
        return 'تبادل الرؤية والمراقبة (LOS)';
      case 'viewshed_360':
        return 'رادار الرصد الدائري 360°';
      case 'artillery':
        return 'رماية المدفعية وقوس القذيفة';
      case 'hlz':
        return 'مهابط المروحيات (HLZ)';
      case 'minefield':
        return 'حقول الألغام وممرات العبور';
      case 'isochrone':
        return 'نطاق التدخل السريع (QRF)';
      case 'symbols':
        return 'الرموز والتشكيلات العسكرية';
      case 'overlays':
        return 'منظومة الشفافات (IPB)';
      case 'routing':
        return 'توجيه القوافل التكتيكي';
      default:
        return 'منظومة العمليات الميدانية (Off-Grid)';
    }
  }
}