import 'package:flutter/material.dart';
import 'package:geolocator/geolocator.dart';
import 'dart:async';
import './clock_in_model.dart';
import './clock_in_api.dart';
import 'package:intl/intl.dart';

class ClockInManager extends StatefulWidget {
  final String userId;
  const ClockInManager({required this.userId, super.key});

  @override
  State<ClockInManager> createState() => _ClockInManagerState();
}

class _ClockInManagerState extends State<ClockInManager> {
  final ClockInApiService _apiService = ClockInApiService();
  late Future<List<ClockInRecord>> _historyFuture;

  // --- 新增：店點相關變數 ---
  List<ClockInStore> _stores = [];
  ClockInStore? _selectedStore;
  bool _isLoadingStores = true;

  Position? _currentPosition;
  double _distanceInMeters = -1;
  String _currentTime = "";
  late Timer _timer;

  @override
  void initState() {
    super.initState();
    _initData();
    _startClock();
  }

  // 初始化資料：先抓店點，再抓歷史紀錄
  Future<void> _initData() async {
    try {
      final stores = await _apiService.fetchStores();
      setState(() {
        _stores = stores;
        if (_stores.isNotEmpty) _selectedStore = _stores.first;
        _isLoadingStores = false;
      });
      _refreshHistory();
      _getCurrentLocation();
    } catch (e) {
      _showMsg("初始化店點失敗: $e");
    }
  }

  void _startClock() {
    _timer = Timer.periodic(const Duration(seconds: 1), (timer) {
      if (mounted) setState(() => _currentTime = DateFormat('HH:mm:ss').format(DateTime.now()));
    });
  }

  // 修改：根據「目前選中店點」計算距離
  Future<void> _getCurrentLocation() async {
    if (_selectedStore == null) return;

    final position = await Geolocator.getCurrentPosition();

    // 使用所選店點的經緯度進行計算
    final distance = Geolocator.distanceBetween(
        position.latitude,
        position.longitude,
        _selectedStore!.latitude,
        _selectedStore!.longitude
    );

    if (mounted) {
      setState(() {
        _currentPosition = position;
        _distanceInMeters = distance;
      });
    }
  }

  void _refreshHistory() {
    final future = _apiService.fetchHistory(widget.userId);
    setState(() => _historyFuture = future);
  }

  // 修改：打卡動作加入 StoreId 與動態距離判斷
  Future<void> _handleClockIn(String type) async {
    if (_selectedStore == null) {
      _showMsg("錯誤：請先選擇打卡店點");
      return;
    }

    await _getCurrentLocation();

    // 使用資料表中的 Distance 欄位作為判斷標準
    if (_distanceInMeters > _selectedStore!.distance || _distanceInMeters == -1) {
      _showMsg("打卡失敗：距離 ${_selectedStore!.storeName} 已超過 ${_selectedStore!.distance} 公尺 (目前: ${_distanceInMeters.toInt()}m)");
      return;
    }

    final newRecord = ClockInRecord(
      userId: int.tryParse(widget.userId),
      type: type,
      latitude: _currentPosition?.latitude,
      longitude: _currentPosition?.longitude,
      storeId: _selectedStore!.storeId, // 使用動態 ID
    );

    bool success = await _apiService.postClockIn(newRecord);
    if (success) {
      _showMsg("[$type] 打卡成功！地點: ${_selectedStore!.storeName}");
      _refreshHistory();
    }
  }

  void _showMsg(String msg) {
    ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text(msg)));
  }

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

  @override
  Widget build(BuildContext context) {
    // 動態判斷是否在選中店點的範圍內
    bool isWithinRange = _selectedStore != null &&
        _distanceInMeters != -1 &&
        _distanceInMeters <= _selectedStore!.distance;

    return Scaffold(
      appBar: AppBar(title: const Text('員工行動打卡')),
      body: _isLoadingStores
          ? const Center(child: CircularProgressIndicator())
          : Column(
        children: [
          // 新增：店點選擇下拉選單區
          _buildStoreSelector(),

          _buildStatusCard(isWithinRange),

          const Divider(height: 1),
          // ... 歷史紀錄標題與清單部分維持不變 (同附件)
          Padding(
            padding: const EdgeInsets.all(16.0),
            child: Row(
              mainAxisAlignment: MainAxisAlignment.spaceBetween,
              children: [
                const Text('今日打卡紀錄', style: TextStyle(fontWeight: FontWeight.bold, fontSize: 16)),
                IconButton(onPressed: _refreshHistory, icon: const Icon(Icons.refresh)),
              ],
            ),
          ),
          Expanded(
            child: FutureBuilder<List<ClockInRecord>>(
              future: _historyFuture,
              builder: (context, snapshot) {
                if (snapshot.connectionState == ConnectionState.waiting) return const Center(child: CircularProgressIndicator());
                if (!snapshot.hasData || snapshot.data!.isEmpty) return const Center(child: Text('查無紀錄'));
                return ListView.builder(
                  itemCount: snapshot.data!.length,
                  itemBuilder: (ctx, i) => _buildHistoryItem(snapshot.data![i]),
                );
              },
            ),
          ),
        ],
      ),
    );
  }

  // 新增：店點選擇器 UI
  Widget _buildStoreSelector() {
    return Container(
      padding: const EdgeInsets.symmetric(horizontal: 20, vertical: 10),
      color: Colors.white,
      child: DropdownButtonFormField<ClockInStore>(
        decoration: const InputDecoration(
          labelText: "選擇打卡店點",
          prefixIcon: Icon(Icons.store),
          border: OutlineInputBorder(),
        ),
        value: _selectedStore,
        items: _stores.map((s) => DropdownMenuItem(
          value: s,
          child: Text(s.storeName),
        )).toList(),
        onChanged: (val) {
          setState(() {
            _selectedStore = val;
            _distanceInMeters = -1; // 切換時重置距離，等待下次定位
          });
          _getCurrentLocation(); // 切換後立即重新計算距離
        },
      ),
    );
  }

  // 修改：狀態卡片顯示
  Widget _buildStatusCard(bool isWithinRange) {
    return Container(
      padding: const EdgeInsets.all(20),
      color: Colors.blue.shade50,
      child: Column(
        children: [
          Text(_currentTime, style: const TextStyle(fontSize: 48, fontWeight: FontWeight.bold, color: Colors.blue)),
          const SizedBox(height: 10),
          if (_selectedStore != null) ...[
            Text(_selectedStore!.storeAddress ?? "", style: const TextStyle(color: Colors.blueGrey)),
            const SizedBox(height: 5),
            Row(
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                Icon(Icons.location_on, color: isWithinRange ? Colors.green : Colors.red),
                Text(
                  isWithinRange
                      ? "已進入 ${_selectedStore!.storeName} 範圍"
                      : "距離過遠: ${_distanceInMeters.toInt()}m (限制: ${_selectedStore!.distance}m)",
                  style: TextStyle(color: isWithinRange ? Colors.green : Colors.red, fontWeight: FontWeight.bold),
                ),
              ],
            ),
          ],
          const SizedBox(height: 20),
          Row(
            children: [
              Expanded(child: _actionBtn("上班打卡", Colors.blue, () => _handleClockIn("上班"))),
              const SizedBox(width: 15),
              Expanded(child: _actionBtn("下班打卡", Colors.orange, () => _handleClockIn("下班"))),
            ],
          )
        ],
      ),
    );
  }

  // _actionBtn 與 _buildHistoryItem 維持與附件原程式相同...
  Widget _actionBtn(String label, Color color, VoidCallback onPressed) {
    return ElevatedButton(
      style: ElevatedButton.styleFrom(backgroundColor: color, foregroundColor: Colors.white, padding: const EdgeInsets.symmetric(vertical: 15)),
      onPressed: onPressed,
      child: Text(label, style: const TextStyle(fontSize: 18)),
    );
  }

  Widget _buildHistoryItem(ClockInRecord record) {
    return ListTile(
      leading: CircleAvatar(backgroundColor: record.typeColor, child: Text(record.type?[0] ?? '', style: const TextStyle(color: Colors.white))),
      title: Text("${record.type} - ${record.formattedTime}"),
      subtitle: Text(record.formattedDate),
      trailing: const Icon(Icons.check_circle, color: Colors.green, size: 16),
    );
  }
}