import 'package:flutter/material.dart';
import 'package:latlong2/latlong.dart';
import '../models/stop.dart';
import '../services/database.dart';
import '../services/geocoding.dart';
import '../hoogerheide_streets.dart';

class BuilderPage extends StatefulWidget {
  final int routeId;
  final VoidCallback onSave;
  const BuilderPage({super.key, required this.routeId, required this.onSave});
  @override
  State<BuilderPage> createState() => _BuilderPageState();
}

class _BuilderPageState extends State<BuilderPage> {
  final _db = DatabaseService();
  final _geocoding = GeocodingService();
  final _streetCtrl = TextEditingController();
  final _numCtrl = TextEditingController();

  final List<_StreetEntry> _entries = [];
  final List<String> _currentNums = [];
  final Map<String, Set<String>> _currentPapers = {};

  bool _saving = false;

  static const _availablePapers = ['BN', 'AD', 'TEL', 'VK'];
  static const _npColors = {
    'BN': Colors.red,
    'AD': Colors.blue,
    'TEL': Colors.orange,
    'VK': Colors.purple,
  };

  @override
  void dispose() {
    _streetCtrl.dispose();
    _numCtrl.dispose();
    super.dispose();
  }

  void _addHouseNumber() {
    final n = _numCtrl.text.trim();
    if (n.isNotEmpty && !_currentNums.contains(n)) {
      setState(() {
        _currentNums.add(n);
        _currentPapers[n] = {'BN'}; // default newspaper
      });
    }
    _numCtrl.clear();
  }

  void _togglePaper(String num, String paper) {
    setState(() {
      final current = _currentPapers[num] ?? {'BN'};
      if (current.contains(paper)) {
        current.remove(paper);
      } else {
        current.add(paper);
      }
      _currentPapers[num] = current;
    });
  }

  void _saveStreet() {
    if (_currentNums.isEmpty || _streetCtrl.text.trim().isEmpty) return;
    setState(() {
      _entries.add(_StreetEntry(
        street: _streetCtrl.text.trim(),
        numPapers: Map.from(_currentPapers),
      ));
      _currentNums.clear();
      _currentPapers.clear();
      _streetCtrl.clear();
    });
  }

  void _removeEntry(_StreetEntry entry) {
    setState(() => _entries.remove(entry));
  }

  Future<void> _saveAll() async {
    if (_entries.isEmpty) return;
    setState(() => _saving = true);

    try {
      var seq = (await _db.getMaxSequence(widget.routeId) ?? -1) + 1;

      for (final entry in _entries) {
        for (final npEntry in entry.numPapers.entries) {
          final houseNum = npEntry.key;
          final papers = npEntry.value.isEmpty ? {'BN'} : npEntry.value;

          // Geocode: try GeocodingService first, fallback to hoogerheide_streets.dart
          LatLng coords;
          try {
            coords = await _geocoding.geocode(entry.street, houseNum);
          } catch (_) {
            coords = _geocodeFromStreets(entry.street, houseNum);
          }

          await _db.insertStop(
            Stop(
              street: entry.street,
              houseNumber: houseNum,
              newspapers: papers.toList(),
              lat: coords.latitude,
              lng: coords.longitude,
              sequence: seq++,
            ),
            widget.routeId,
          );
        }
      }

      widget.onSave();
      if (mounted) Navigator.pop(context);
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(content: Text('Error saving: $e'), backgroundColor: Colors.red),
        );
      }
    } finally {
      if (mounted) setState(() => _saving = false);
    }
  }

  /// Fallback geocode using hoogerheide_streets.dart with house-number offset
  LatLng _geocodeFromStreets(String street, String houseNum) {
    final ns = _normalize(street);

    // Exact match
    for (final entry in HoogerheideStreets.streetCoords.entries) {
      if (_normalize(entry.key) == ns) {
        return _offsetByHouseNumber(entry.value[0], entry.value[1], houseNum);
      }
    }
    // Partial match
    for (final entry in HoogerheideStreets.streetCoords.entries) {
      final ek = _normalize(entry.key);
      if (ns.contains(ek) || ek.contains(ns)) {
        return _offsetByHouseNumber(entry.value[0], entry.value[1], houseNum);
      }
    }
    return const LatLng(51.4243390, 4.3238380);
  }

  LatLng _offsetByHouseNumber(double baseLat, double baseLng, String houseNum) {
    final hn = int.tryParse(houseNum.replaceAll(RegExp(r'[A-Za-z]'), '')) ?? 1;
    return LatLng(
      baseLat + (hn - 1) * 0.00015,
      baseLng + ((hn / 25).floor() % 2 == 0 ? 0 : 0.0002),
    );
  }

  String _normalize(String name) =>
      name.replaceAll(RegExp(r'[–—]'), ' ').replaceAll(RegExp(r'\s+'), ' ').trim().toLowerCase();

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Add Stops'),
        actions: [
          if (_saving)
            const Padding(
              padding: EdgeInsets.all(16),
              child: SizedBox(
                width: 20, height: 20,
                child: CircularProgressIndicator(strokeWidth: 2, color: Colors.white),
              ),
            )
          else
            IconButton(
              icon: const Icon(Icons.check),
              onPressed: _entries.isEmpty ? null : _saveAll,
              tooltip: 'Save all stops',
            ),
        ],
      ),
      body: ListView(
        padding: const EdgeInsets.all(16),
        children: [
          // Input card
          Card(
            child: Padding(
              padding: const EdgeInsets.all(16),
              child: Column(
                crossAxisAlignment: CrossAxisAlignment.start,
                children: [
                  TextField(
                    controller: _streetCtrl,
                    decoration: const InputDecoration(
                      labelText: 'Street name',
                      border: OutlineInputBorder(),
                    ),
                    textCapitalization: TextCapitalization.words,
                  ),
                  const SizedBox(height: 12),
                  Row(
                    children: [
                      Expanded(
                        child: TextField(
                          controller: _numCtrl,
                          decoration: const InputDecoration(
                            labelText: 'House number',
                            border: OutlineInputBorder(),
                          ),
                          onSubmitted: (_) => _addHouseNumber(),
                        ),
                      ),
                      const SizedBox(width: 8),
                      IconButton.filled(
                        onPressed: _addHouseNumber,
                        icon: const Icon(Icons.add),
                      ),
                    ],
                  ),
                  if (_currentNums.isNotEmpty) ...[
                    const SizedBox(height: 12),
                    Wrap(
                      spacing: 8,
                      runSpacing: 8,
                      children: _currentNums.map(_buildHouseNumberChip).toList(),
                    ),
                  ],
                  const SizedBox(height: 12),
                  SizedBox(
                    width: double.infinity,
                    child: ElevatedButton.icon(
                      onPressed: _currentNums.isEmpty ? null : _saveStreet,
                      icon: const Icon(Icons.add_road),
                      label: const Text('Add Street'),
                    ),
                  ),
                ],
              ),
            ),
          ),

          // Saved entries
          if (_entries.isNotEmpty) ...[
            const SizedBox(height: 16),
            const Text('Stops to add:', style: TextStyle(fontWeight: FontWeight.bold, fontSize: 16)),
            const SizedBox(height: 8),
            ..._entries.map((entry) => Card(
              child: ListTile(
                leading: const CircleAvatar(child: Icon(Icons.location_on)),
                title: Text(entry.street),
                subtitle: Text(
                  entry.numPapers.entries.map((e) => '${e.key}: ${e.value.join(",")}').join('; '),
                ),
                trailing: IconButton(
                  icon: const Icon(Icons.delete_outline, color: Colors.red),
                  onPressed: () => _removeEntry(entry),
                ),
              ),
            )),
          ],
        ],
      ),
    );
  }

  Widget _buildHouseNumberChip(String num) {
    final current = _currentPapers[num] ?? {'BN'};
    return Container(
      padding: const EdgeInsets.all(8),
      decoration: BoxDecoration(
        color: Colors.grey[200],
        borderRadius: BorderRadius.circular(8),
      ),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        mainAxisSize: MainAxisSize.min,
        children: [
          Row(
            mainAxisSize: MainAxisSize.min,
            children: [
              Text(num, style: const TextStyle(fontWeight: FontWeight.bold)),
              const SizedBox(width: 4),
              GestureDetector(
                onTap: () => setState(() {
                  _currentNums.remove(num);
                  _currentPapers.remove(num);
                }),
                child: const Icon(Icons.close, size: 16),
              ),
            ],
          ),
          const SizedBox(height: 4),
          Wrap(
            spacing: 4,
            children: _availablePapers.map((np) => FilterChip(
              label: Text(np, style: const TextStyle(fontSize: 11)),
              selected: current.contains(np),
              selectedColor: _npColors[np],
              onSelected: (_) => _togglePaper(num, np),
              visualDensity: VisualDensity.compact,
              padding: EdgeInsets.zero,
            )).toList(),
          ),
        ],
      ),
    );
  }
}

class _StreetEntry {
  final String street;
  final Map<String, Set<String>> numPapers;
  _StreetEntry({required this.street, required this.numPapers});
}