import 'package:flutter/material.dart';
import 'package:intaleq_maps/intaleq_maps.dart';
import '../services/viewshed_360_engine.dart';
import '../services/offline_los_engine.dart';
import '../services/military_grid_utils.dart';

/// Tactical Bottom Sheet for 360° Radial Viewshed (تحليل حقل الرؤية الدائري 360 درجة)
class TacticalViewshedSheet extends StatefulWidget {
  final LatLng observer;
  final LatLng? currentGps;
  final Function(LatLng newObs)? onUpdateObserver;
  final Function(Viewshed360Report report) onReportUpdated;
  final VoidCallback onPickObserverOnMap;
  final VoidCallback onClose;

  const TacticalViewshedSheet({
    super.key,
    required this.observer,
    this.currentGps,
    this.onUpdateObserver,
    required this.onReportUpdated,
    required this.onPickObserverOnMap,
    required this.onClose,
  });

  @override
  State<TacticalViewshedSheet> createState() => _TacticalViewshedSheetState();
}

class _TacticalViewshedSheetState extends State<TacticalViewshedSheet> with SingleTickerProviderStateMixin {
  late LatLng _currentObs;
  double _radiusKm = 5.0;
  double _observerHeightM = 2.0;
  final int _rayCount = 360; // 360 continuous 1-degree radial rays (15-20ms)
  Viewshed360Report? _report;
  bool _isCalculating = false;
  bool _showCoordInputs = false;

  late TabController _coordTabController;
  late TextEditingController _obsEastingCtrl;
  late TextEditingController _obsNorthingCtrl;
  late TextEditingController _obsLatCtrl;
  late TextEditingController _obsLngCtrl;

  @override
  void initState() {
    super.initState();
    _currentObs = widget.observer;
    _coordTabController = TabController(length: 2, vsync: this);

    final obsMil = MilitaryGridUtils.fromLatLng(_currentObs);
    _obsEastingCtrl = TextEditingController(text: obsMil.eastingStr);
    _obsNorthingCtrl = TextEditingController(text: obsMil.northingStr);
    _obsLatCtrl = TextEditingController(text: _currentObs.latitude.toStringAsFixed(6));
    _obsLngCtrl = TextEditingController(text: _currentObs.longitude.toStringAsFixed(6));

    WidgetsBinding.instance.addPostFrameCallback((_) {
      if (mounted) _computeViewshed();
    });
  }

  @override
  void didUpdateWidget(covariant TacticalViewshedSheet oldWidget) {
    super.didUpdateWidget(oldWidget);
    if (oldWidget.observer != widget.observer) {
      _currentObs = widget.observer;
      final obsMil = MilitaryGridUtils.fromLatLng(_currentObs);
      _obsEastingCtrl.text = obsMil.eastingStr;
      _obsNorthingCtrl.text = obsMil.northingStr;
      _obsLatCtrl.text = _currentObs.latitude.toStringAsFixed(6);
      _obsLngCtrl.text = _currentObs.longitude.toStringAsFixed(6);
      WidgetsBinding.instance.addPostFrameCallback((_) {
        if (mounted) _computeViewshed();
      });
    }
  }

  @override
  void dispose() {
    _coordTabController.dispose();
    _obsEastingCtrl.dispose();
    _obsNorthingCtrl.dispose();
    _obsLatCtrl.dispose();
    _obsLngCtrl.dispose();
    super.dispose();
  }

  void _computeViewshed() async {
    setState(() => _isCalculating = true);
    final report = await Viewshed360Engine.calculateAsync(
      observer: _currentObs,
      radiusMeters: _radiusKm * 1000.0,
      observerHeightM: _observerHeightM,
      rayCount: _rayCount,
    );

    if (mounted) {
      setState(() {
        _report = report;
        _isCalculating = false;
      });
      widget.onReportUpdated(report);
    }
  }

  void _applyManualCoordinates() {
    LatLng newObs = _currentObs;
    if (_coordTabController.index == 0) {
      final e = double.tryParse(_obsEastingCtrl.text) ?? 0;
      final n = double.tryParse(_obsNorthingCtrl.text) ?? 0;
      if (e > 100000 && n > 1000000) {
        newObs = MilitaryGridUtils.toLatLng(easting: e, northing: n);
      }
    } else {
      final lat = double.tryParse(_obsLatCtrl.text);
      final lng = double.tryParse(_obsLngCtrl.text);
      if (lat != null && lng != null) {
        newObs = LatLng(lat, lng);
      }
    }

    setState(() {
      _currentObs = newObs;
      _showCoordInputs = false;
    });

    widget.onUpdateObserver?.call(newObs);
    _computeViewshed();
  }

  @override
  Widget build(BuildContext context) {
    final obsMil = MilitaryGridUtils.fromLatLng(_currentObs);
    final obsElev = JordanDemSurface.elevationAt(_currentObs.latitude, _currentObs.longitude);

    return Container(
      padding: const EdgeInsets.all(16),
      decoration: const BoxDecoration(
        color: Color(0xFF090E1A),
        borderRadius: BorderRadius.vertical(top: Radius.circular(24)),
        border: Border(top: BorderSide(color: Color(0xFF38BDF8), width: 1.5)),
      ),
      child: SafeArea(
        top: false,
        child: SingleChildScrollView(
          child: Column(
            mainAxisSize: MainAxisSize.min,
            crossAxisAlignment: CrossAxisAlignment.stretch,
            children: [
              // Handle Bar
              Center(
                child: Container(
                  width: 40,
                  height: 4,
                  margin: const EdgeInsets.only(bottom: 12),
                  decoration: BoxDecoration(
                    color: Colors.white24,
                    borderRadius: BorderRadius.circular(2),
                  ),
                ),
              ),

              // Header Bar
              Row(
                children: [
                  Container(
                    padding: const EdgeInsets.all(8),
                    decoration: BoxDecoration(
                      color: const Color(0xFF22C55E).withValues(alpha: 0.15),
                      borderRadius: BorderRadius.circular(10),
                      border: Border.all(color: const Color(0xFF22C55E)),
                    ),
                    child: _isCalculating
                        ? const SizedBox(
                            width: 22,
                            height: 22,
                            child: CircularProgressIndicator(strokeWidth: 2, color: Color(0xFF4ADE80)),
                          )
                        : const Icon(Icons.radar, color: Color(0xFF4ADE80), size: 22),
                  ),
                  const SizedBox(width: 12),
                  Expanded(
                    child: Column(
                      crossAxisAlignment: CrossAxisAlignment.start,
                      children: [
                        const Text(
                          'منظومة حقل الرؤية والرصد 360° (360° Viewshed)',
                          style: TextStyle(color: Colors.white, fontSize: 13, fontWeight: FontWeight.bold),
                          overflow: TextOverflow.ellipsis,
                        ),
                        Text(
                          'مركز الرصد: ${obsMil.arabicFullFormat} • ارتفاع: ${obsElev.round()}م',
                          style: const TextStyle(color: Color(0xFF38BDF8), fontSize: 11),
                          overflow: TextOverflow.ellipsis,
                        ),
                      ],
                    ),
                  ),
                  IconButton(
                    onPressed: widget.onClose,
                    icon: const Icon(Icons.close, color: Colors.white70, size: 20),
                  ),
                ],
              ),

              const SizedBox(height: 12),

              // Metrics Card
              if (_report != null)
                Container(
                  padding: const EdgeInsets.all(16),
                  decoration: BoxDecoration(
                    color: const Color(0xFF0F172A),
                    borderRadius: BorderRadius.circular(12),
                    border: Border.all(color: Colors.white10),
                  ),
                  child: Row(
                    mainAxisAlignment: MainAxisAlignment.spaceAround,
                    children: [
                      _buildMetricCol(
                        'المساحة المكشوفة',
                        '${_report!.visibleAreaSqKm.toStringAsFixed(1)} كم²',
                        const Color(0xFF4ADE80),
                      ),
                      _buildDivider(),
                      _buildMetricCol(
                        'كفاءة التغطية',
                        '${_report!.visibilityPercentage}%',
                        _report!.visibilityPercentage > 50 ? const Color(0xFF4ADE80) : const Color(0xFFF59E0B),
                      ),
                      _buildDivider(),
                      _buildMetricCol(
                        'متوسط المدى',
                        '${_report!.averageSightRangeKm.toStringAsFixed(1)} كم',
                        const Color(0xFF38BDF8),
                      ),
                    ],
                  ),
                ),

              const SizedBox(height: 12),

              // Radius Slider
              Row(
                mainAxisAlignment: MainAxisAlignment.spaceBetween,
                children: [
                  Row(
                    children: [
                      const Icon(Icons.blur_circular, size: 16, color: Color(0xFF38BDF8)),
                      const SizedBox(width: 6),
                      Text(
                        'نصف قطر المسح: ${_radiusKm.toStringAsFixed(1)} كم',
                        style: const TextStyle(color: Colors.white, fontSize: 12, fontWeight: FontWeight.bold),
                      ),
                    ],
                  ),
                  Text(
                    '${(_radiusKm * 1000).round()} متر',
                    style: const TextStyle(color: Colors.white60, fontSize: 11),
                  ),
                ],
              ),
              Slider(
                value: _radiusKm,
                min: 1.0,
                max: 15.0,
                divisions: 14,
                activeColor: const Color(0xFF38BDF8),
                inactiveColor: Colors.white12,
                onChanged: (val) {
                  setState(() => _radiusKm = val);
                  _computeViewshed();
                },
              ),

              // Optic Height Segmented Choice
              Row(
                children: [
                  const Icon(Icons.height, size: 16, color: Color(0xFFF59E0B)),
                  const SizedBox(width: 6),
                  const Text(
                    'ارتفاع نقطة الرصد / البصريات:',
                    style: TextStyle(color: Colors.white, fontSize: 12, fontWeight: FontWeight.bold),
                  ),
                ],
              ),
              const SizedBox(height: 6),
              Row(
                children: [
                  _buildHeightChip(2.0, '2م (منظار)'),
                  const SizedBox(width: 6),
                  _buildHeightChip(5.0, '5م (مركبة)'),
                  const SizedBox(width: 6),
                  _buildHeightChip(10.0, '10م (سارية)'),
                  const SizedBox(width: 6),
                  _buildHeightChip(25.0, '25م (برج)'),
                ],
              ),

              const SizedBox(height: 12),

              // Action Buttons Row: [Manual Coordinates / Map Selection / Current GPS]
              Row(
                children: [
                  Expanded(
                    child: OutlinedButton.icon(
                      onPressed: () => setState(() => _showCoordInputs = !_showCoordInputs),
                      style: OutlinedButton.styleFrom(
                        foregroundColor: const Color(0xFF38BDF8),
                        side: const BorderSide(color: Color(0xFF38BDF8)),
                        padding: const EdgeInsets.all(16),
                        shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(10)),
                      ),
                      icon: Icon(_showCoordInputs ? Icons.expand_less : Icons.edit_location_alt, size: 16),
                      label: const Text('إدخال إحداثيات', style: TextStyle(fontSize: 11, fontWeight: FontWeight.bold)),
                    ),
                  ),
                  const SizedBox(width: 8),
                  Expanded(
                    child: ElevatedButton.icon(
                      onPressed: widget.onPickObserverOnMap,
                      style: ElevatedButton.styleFrom(
                        backgroundColor: const Color(0xFF0284C7),
                        foregroundColor: Colors.white,
                        padding: const EdgeInsets.all(16),
                        shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(10)),
                      ),
                      icon: const Icon(Icons.touch_app, size: 16),
                      label: const Text('نقر من الخريطة 👁️', style: TextStyle(fontSize: 11, fontWeight: FontWeight.bold)),
                    ),
                  ),
                  if (widget.currentGps != null) ...[
                    const SizedBox(width: 8),
                    IconButton(
                      tooltip: 'استخدام موقعي الحالي',
                      style: IconButton.styleFrom(
                        backgroundColor: const Color(0xFF1E293B),
                        foregroundColor: const Color(0xFF22C55E),
                        shape: RoundedRectangleBorder(
                          borderRadius: BorderRadius.circular(10),
                          side: const BorderSide(color: Color(0xFF22C55E)),
                        ),
                      ),
                      icon: const Icon(Icons.my_location, size: 18),
                      onPressed: () {
                        setState(() {
                          _currentObs = widget.currentGps!;
                        });
                        widget.onUpdateObserver?.call(_currentObs);
                        _computeViewshed();
                      },
                    ),
                  ],
                ],
              ),

              // Coordinate Inputs Box
              if (_showCoordInputs) ...[
                const SizedBox(height: 12),
                Container(
                  padding: const EdgeInsets.all(12),
                  decoration: BoxDecoration(
                    color: const Color(0xFF1E293B),
                    borderRadius: BorderRadius.circular(12),
                    border: Border.all(color: Colors.white12),
                  ),
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.stretch,
                    children: [
                      TabBar(
                        controller: _coordTabController,
                        indicatorColor: const Color(0xFF38BDF8),
                        labelColor: const Color(0xFF38BDF8),
                        unselectedLabelColor: Colors.white60,
                        tabs: const [
                          Tab(text: 'شبكة عسكرية (UTM)'),
                          Tab(text: 'درجات عشرية (Lat/Lng)'),
                        ],
                      ),
                      const SizedBox(height: 10),
                      SizedBox(
                        height: 70,
                        child: TabBarView(
                          controller: _coordTabController,
                          children: [
                            // UTM
                            Row(
                              children: [
                                Expanded(
                                  child: TextField(
                                    controller: _obsEastingCtrl,
                                    keyboardType: TextInputType.number,
                                    style: const TextStyle(color: Colors.white, fontSize: 12),
                                    decoration: InputDecoration(
                                      labelText: 'شرقيات (Easting)',
                                      labelStyle: const TextStyle(color: Colors.white60, fontSize: 11),
                                      filled: true,
                                      fillColor: const Color(0xFF0F172A),
                                      border: OutlineInputBorder(borderRadius: BorderRadius.circular(8)),
                                    ),
                                  ),
                                ),
                                const SizedBox(width: 8),
                                Expanded(
                                  child: TextField(
                                    controller: _obsNorthingCtrl,
                                    keyboardType: TextInputType.number,
                                    style: const TextStyle(color: Colors.white, fontSize: 12),
                                    decoration: InputDecoration(
                                      labelText: 'شماليات (Northing)',
                                      labelStyle: const TextStyle(color: Colors.white60, fontSize: 11),
                                      filled: true,
                                      fillColor: const Color(0xFF0F172A),
                                      border: OutlineInputBorder(borderRadius: BorderRadius.circular(8)),
                                    ),
                                  ),
                                ),
                              ],
                            ),
                            // Decimal
                            Row(
                              children: [
                                Expanded(
                                  child: TextField(
                                    controller: _obsLatCtrl,
                                    keyboardType: const TextInputType.numberWithOptions(decimal: true),
                                    style: const TextStyle(color: Colors.white, fontSize: 12),
                                    decoration: InputDecoration(
                                      labelText: 'دائرة العرض (Lat)',
                                      labelStyle: const TextStyle(color: Colors.white60, fontSize: 11),
                                      filled: true,
                                      fillColor: const Color(0xFF0F172A),
                                      border: OutlineInputBorder(borderRadius: BorderRadius.circular(8)),
                                    ),
                                  ),
                                ),
                                const SizedBox(width: 8),
                                Expanded(
                                  child: TextField(
                                    controller: _obsLngCtrl,
                                    keyboardType: const TextInputType.numberWithOptions(decimal: true),
                                    style: const TextStyle(color: Colors.white, fontSize: 12),
                                    decoration: InputDecoration(
                                      labelText: 'خط الطول (Lng)',
                                      labelStyle: const TextStyle(color: Colors.white60, fontSize: 11),
                                      filled: true,
                                      fillColor: const Color(0xFF0F172A),
                                      border: OutlineInputBorder(borderRadius: BorderRadius.circular(8)),
                                    ),
                                  ),
                                ),
                              ],
                            ),
                          ],
                        ),
                      ),
                      const SizedBox(height: 8),
                      ElevatedButton(
                        onPressed: _applyManualCoordinates,
                        style: ElevatedButton.styleFrom(
                          backgroundColor: const Color(0xFF22C55E),
                          foregroundColor: Colors.white,
                          padding: const EdgeInsets.all(16),
                          shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(8)),
                        ),
                        child: const Text('تطبيق الإحداثيات وإعادة الرصد', style: TextStyle(fontWeight: FontWeight.bold)),
                      ),
                    ],
                  ),
                ),
              ],
            ],
          ),
        ),
      ),
    );
  }

  Widget _buildHeightChip(double h, String label) {
    final isSelected = _observerHeightM == h;
    return Expanded(
      child: InkWell(
        onTap: () {
          setState(() => _observerHeightM = h);
          _computeViewshed();
        },
        child: Container(
          padding: const EdgeInsets.all(16),
          decoration: BoxDecoration(
            color: isSelected ? const Color(0xFF0284C7) : const Color(0xFF1E293B),
            borderRadius: BorderRadius.circular(8),
            border: Border.all(color: isSelected ? const Color(0xFF38BDF8) : Colors.white12),
          ),
          child: Center(
            child: Text(
              label,
              style: TextStyle(
                color: isSelected ? Colors.white : Colors.white70,
                fontSize: 9.5,
                fontWeight: isSelected ? FontWeight.bold : FontWeight.normal,
              ),
            ),
          ),
        ),
      ),
    );
  }

  Widget _buildMetricCol(String title, String val, Color color) {
    return Column(
      children: [
        Text(title, style: const TextStyle(color: Colors.white60, fontSize: 10)),
        const SizedBox(height: 2),
        Text(val, style: TextStyle(color: color, fontSize: 13, fontWeight: FontWeight.bold)),
      ],
    );
  }

  Widget _buildDivider() {
    return Container(width: 1, height: 26, color: Colors.white12);
  }
}