import 'dart:async';

import 'package:flutter/material.dart';

import '../api/oa_client.dart';
import '../device/device_bridge.dart';
import '../theme.dart';
import '../widgets/tencent_map_thumb.dart';
import '../widgets/wecom.dart';

class GeoPlace {
  GeoPlace({required this.lat, required this.lng, required this.title, required this.address, this.distance});
  final double lat;
  final double lng;
  final String title;
  final String address;
  final num? distance;

  Map<String, dynamic> toMeta() => {
        'lat': lat,
        'lng': lng,
        'title': title,
        'address': address,
      };
}

class LocationPickPage extends StatefulWidget {
  const LocationPickPage({super.key, required this.api});
  final OaClient api;

  @override
  State<LocationPickPage> createState() => _LocationPickPageState();
}

class _LocationPickPageState extends State<LocationPickPage> {
  double? _lat;
  double? _lng;
  GeoPlace? _picked;
  List<GeoPlace> _pois = [];
  bool _loading = true;
  String _err = '';
  String _q = '';
  Timer? _searchDebounce;

  @override
  void initState() {
    super.initState();
    _locate();
  }

  @override
  void dispose() {
    _searchDebounce?.cancel();
    super.dispose();
  }

  Future<void> _locate() async {
    setState(() {
      _loading = true;
      _err = '';
    });
    try {
      Map<String, double>? loc;
      try {
        loc = await DeviceBridge.getLocation();
      } catch (_) {}
      final lat = loc?['lat'];
      final lng = loc?['lng'];
      if (lat == null || lng == null) {
        throw Exception('没有拿到定位，请允许位置权限并打开系统定位');
      }
      await _loadAround(lat, lng);
    } catch (e) {
      if (mounted) setState(() { _loading = false; _err = '$e'; });
    }
  }

  Future<void> _loadAround(double lat, double lng) async {
    final data = await widget.api.post('/office/geo/reverse', {'lat': lat, 'lng': lng});
    if (!mounted) return;
    final map = data is Map ? Map<String, dynamic>.from(data) : <String, dynamic>{};
    final here = GeoPlace(
      lat: lat,
      lng: lng,
      title: '${map['title'] ?? '当前位置'}',
      address: '${map['address'] ?? ''}',
    );
    final pois = <GeoPlace>[here];
    final raw = map['pois'];
    if (raw is List) {
      for (final e in raw) {
        if (e is! Map) continue;
        final plat = (e['lat'] as num?)?.toDouble();
        final plng = (e['lng'] as num?)?.toDouble();
        if (plat == null || plng == null) continue;
        pois.add(GeoPlace(
          lat: plat,
          lng: plng,
          title: '${e['title'] ?? e['address'] ?? '地点'}',
          address: '${e['address'] ?? ''}',
          distance: e['distance'] as num?,
        ));
      }
    }
    setState(() {
      _lat = lat;
      _lng = lng;
      _picked = here;
      _pois = pois;
      _loading = false;
      _err = '';
    });
  }

  void _onSearch(String q) {
    _q = q.trim();
    _searchDebounce?.cancel();
    if (_q.isEmpty) {
      if (_lat != null && _lng != null) _loadAround(_lat!, _lng!);
      return;
    }
    _searchDebounce = Timer(const Duration(milliseconds: 350), () async {
      try {
        final data = await widget.api.get('/office/geo/suggest', query: {
          'keyword': _q,
          if (_lat != null) 'lat': '$_lat',
          if (_lng != null) 'lng': '$_lng',
        });
        if (!mounted) return;
        final list = data is List ? data : (data is Map ? (data['items'] ?? data['data'] ?? []) : []);
        final pois = <GeoPlace>[];
        for (final e in (list is List ? list : <dynamic>[])) {
          if (e is! Map) continue;
          final plat = (e['lat'] as num?)?.toDouble();
          final plng = (e['lng'] as num?)?.toDouble();
          if (plat == null || plng == null) continue;
          pois.add(GeoPlace(
            lat: plat,
            lng: plng,
            title: '${e['title'] ?? '地点'}',
            address: '${e['address'] ?? ''}',
            distance: e['distance'] as num?,
          ));
        }
        setState(() {
          _pois = pois;
          if (pois.isNotEmpty) _picked = pois.first;
        });
      } catch (_) {}
    });
  }

  String _dist(num? d) {
    if (d == null) return '';
    if (d < 1) return '当前位置';
    if (d < 1000) return '${d.round()}m';
    return '${(d / 1000).toStringAsFixed(1)}km';
  }

  @override
  Widget build(BuildContext context) {
    final picked = _picked;
    return Scaffold(
      backgroundColor: Colors.white,
      appBar: AppBar(
        leading: TextButton(onPressed: () => Navigator.pop(context), child: const Text('取消')),
        title: const Text('发送位置'),
        actions: [
          Padding(
            padding: const EdgeInsets.only(right: 8, top: 8, bottom: 8),
            child: FilledButton(
              style: FilledButton.styleFrom(backgroundColor: kWeGreen, minimumSize: const Size(64, 32)),
              onPressed: picked == null ? null : () => Navigator.pop(context, picked),
              child: const Text('发送'),
            ),
          ),
        ],
      ),
      body: Column(
        children: [
          SizedBox(
            height: 220,
            width: double.infinity,
            child: Stack(
              children: [
                if (picked != null)
                  Positioned.fill(
                    child: TencentMapThumb(api: widget.api, lat: picked.lat, lng: picked.lng, height: 220),
                  )
                else
                  const ColoredBox(color: Color(0xFFE8F5E9), child: Center(child: CircularProgressIndicator())),
                Positioned(
                  left: 12,
                  bottom: 12,
                  child: Material(
                    color: Colors.white,
                    shape: const CircleBorder(),
                    elevation: 2,
                    child: IconButton(
                      onPressed: _locate,
                      icon: const Icon(Icons.my_location, color: kBind),
                    ),
                  ),
                ),
              ],
            ),
          ),
          Padding(
            padding: const EdgeInsets.fromLTRB(12, 8, 12, 4),
            child: WxSearchBar(hint: '搜索地点', onChanged: _onSearch),
          ),
          if (_err.isNotEmpty)
            Padding(
              padding: const EdgeInsets.all(12),
              child: Text(_err, style: const TextStyle(color: kDanger, fontSize: 13)),
            ),
          Expanded(
            child: _loading
                ? const Center(child: CircularProgressIndicator())
                : ListView.builder(
                    itemCount: _pois.length,
                    itemBuilder: (_, i) {
                      final p = _pois[i];
                      final on = picked?.lat == p.lat && picked?.lng == p.lng && picked?.title == p.title;
                      return InkWell(
                        onTap: () => setState(() => _picked = p),
                        child: Padding(
                          padding: const EdgeInsets.fromLTRB(16, 12, 16, 0),
                          child: Row(
                            children: [
                              Expanded(
                                child: Container(
                                  padding: const EdgeInsets.only(bottom: 12),
                                  decoration: const BoxDecoration(border: Border(bottom: BorderSide(color: kLine, width: 0.5))),
                                  child: Column(
                                    crossAxisAlignment: CrossAxisAlignment.start,
                                    children: [
                                      Text(p.title, style: const TextStyle(fontSize: 16, color: kInk)),
                                      const SizedBox(height: 2),
                                      Text(
                                        [_dist(p.distance), p.address].where((e) => e.isNotEmpty).join(' | '),
                                        maxLines: 1,
                                        overflow: TextOverflow.ellipsis,
                                        style: const TextStyle(fontSize: 12, color: kMute),
                                      ),
                                    ],
                                  ),
                                ),
                              ),
                              if (on) const Padding(padding: EdgeInsets.only(left: 8), child: Icon(Icons.check, color: kWeGreen)),
                            ],
                          ),
                        ),
                      );
                    },
                  ),
          ),
        ],
      ),
    );
  }
}