import 'dart:async';
import 'package:flutter/material.dart';
import 'package:provider/provider.dart';
import '../../providers/app_provider.dart';
import '../../utils/user_prefs.dart';
import '../../utils/sync/server_sync_service.dart';
import '../../utils/sync/server_data_service.dart';
import '../../utils/toast_util.dart';

/// 服务端实时同步页面
class ServerSyncPage extends StatefulWidget {
  const ServerSyncPage({super.key});

  @override
  State<ServerSyncPage> createState() => _ServerSyncPageState();
}

class _ServerSyncPageState extends State<ServerSyncPage> {
  final UserPrefs _prefs = UserPrefs();
  final _urlController = TextEditingController();
  final _codeController = TextEditingController();

  bool _syncEnabled = false;
  bool _isActivated = false;
  bool _isChecking = false;
  String _expiresText = '';
  Timer? _statusTimer;

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

  @override
  void dispose() {
    _urlController.dispose();
    _codeController.dispose();
    _statusTimer?.cancel();
    super.dispose();
  }

  void _loadSettings() {
    final url = _prefs.syncServerUrl;
    final code = _prefs.syncActivationCode;
    _urlController.text = url;
    _codeController.text = code;
    _isActivated = url.isNotEmpty && code.isNotEmpty;
    _syncEnabled = _isActivated && _prefs.syncEnabled;
    _updateExpiresText();
    if (_isActivated) _startStatusPolling();
  }

  void _updateExpiresText() {
    if (_prefs.syncIsPermanent) {
      _expiresText = '永久有效';
    } else {
      final exp = _prefs.syncExpiresAt;
      if (exp.isNotEmpty) {
        try {
          final dt = DateTime.parse(exp).add(const Duration(hours: 8));
          _expiresText = '有效期至 ${dt.year}-${dt.month.toString().padLeft(2, '0')}-${dt.day.toString().padLeft(2, '0')} '
              '${dt.hour.toString().padLeft(2, '0')}:${dt.minute.toString().padLeft(2, '0')}';
        } catch (_) {
          _expiresText = '有效期至 $exp';
        }
      } else {
        _expiresText = '';
      }
    }
  }

  void _startStatusPolling() {
    _statusTimer?.cancel();
    _statusTimer = Timer.periodic(const Duration(minutes: 1), (_) => _checkStatus());
  }

  Future<void> _checkStatus() async {
    if (!_isActivated) return;
    final result = await ServerSyncService.instance.checkActivation();
    if (!mounted) return;
    if (result == null || result['valid'] != true) {
      await _prefs.setSyncEnabled(false);
      setState(() {
        _isActivated = false;
        _syncEnabled = false;
        _expiresText = '激活码已失效';
      });
      if (mounted) ToastUtil.show(context, '激活码已失效，同步已关闭');
    } else {
      await _prefs.setSyncExpiresAt(result['expires_at'] ?? '');
      await _prefs.setSyncIsPermanent(result['is_permanent'] == true);
      _updateExpiresText();
    }
  }

  Future<void> _checkActivation() async {
    final url = _urlController.text.trim();
    final code = _codeController.text.trim().toUpperCase();
    if (url.isEmpty || code.isEmpty) {
      ToastUtil.show(context, '请输入服务器地址和激活码');
      return;
    }
    setState(() => _isChecking = true);
    await _prefs.setSyncServerUrl(url);
    await _prefs.setSyncActivationCode(code);

    final result = await ServerSyncService.instance.checkActivation();
    if (!mounted) return;
    setState(() => _isChecking = false);

    if (result != null && result['valid'] == true) {
      _isActivated = true;
      await _prefs.setSyncExpiresAt(result['expires_at'] ?? '');
      await _prefs.setSyncIsPermanent(result['is_permanent'] == true);
      _updateExpiresText();
      _startStatusPolling();
      await _prefs.setSyncEnabled(true);
      _syncEnabled = true;
      await ServerSyncService.instance.uploadToServer();
      if (mounted) ToastUtil.show(context, '激活成功，实时同步已开启');
    } else {
      final error = result?['error'] ?? '激活失败';
      if (mounted) ToastUtil.show(context, error.toString());
    }
  }

  Future<void> _toggleSync(bool value) async {
    await _prefs.setSyncEnabled(value);
    setState(() => _syncEnabled = value);

    if (value && _isActivated) {
      await ServerSyncService.instance.uploadToServer();
      final provider = context.read<AppProvider>();
      await provider.loadMovies();
      await provider.loadBooks();
      await provider.loadNotes();
      if (mounted) ToastUtil.show(context, '已切换到服务端数据');
    } else {
      // 关闭同步：从服务端下载最新数据到本地
      if (mounted) ToastUtil.show(context, '正在从服务端同步数据...');
      final success = await ServerSyncService.instance.downloadToLocal();
      if (mounted) {
        if (success) {
          final provider = context.read<AppProvider>();
          await provider.loadMovies();
          await provider.loadBooks();
          await provider.loadNotes();
          ToastUtil.show(context, '数据已下载到本地');
        } else {
          ToastUtil.show(context, '下载失败，使用本地数据');
        }
      }
    }
  }

  Future<void> _disconnect() async {
    final confirm = await showDialog<bool>(
      context: context,
      builder: (ctx) => AlertDialog(
        backgroundColor: Colors.white,
        shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(16)),
        title: const Text('断开连接', style: TextStyle(fontSize: 18, fontWeight: FontWeight.w600)),
        content: const Text('将清除服务器配置和激活信息，确定要断开吗？', style: TextStyle(fontSize: 14, color: Color(0xFF666666))),
        actions: [
          TextButton(onPressed: () => Navigator.pop(ctx, false), child: const Text('取消', style: TextStyle(color: Color(0xFF999999)))),
          TextButton(onPressed: () => Navigator.pop(ctx, true), child: const Text('确定', style: TextStyle(color: Color(0xFFE53935)))),
        ],
      ),
    );
    if (confirm != true) return;

    _statusTimer?.cancel();
    await _toggleSync(false);
    await _prefs.setSyncServerUrl('');
    await _prefs.setSyncActivationCode('');
    await _prefs.setSyncExpiresAt('');
    await _prefs.setSyncIsPermanent(false);
    await _prefs.setSyncEnabled(false);

    setState(() {
      _isActivated = false;
      _syncEnabled = false;
      _expiresText = '';
      _urlController.clear();
      _codeController.clear();
    });
    if (mounted) ToastUtil.show(context, '已断开连接');
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: const Color(0xFFF8F8F8),
      appBar: AppBar(title: const Text('服务端实时同步')),
      body: ListView(padding: const EdgeInsets.all(20), children: [
        // 状态卡片
        Container(
          padding: const EdgeInsets.all(20),
          decoration: BoxDecoration(color: Colors.white, borderRadius: BorderRadius.circular(16),
            boxShadow: [BoxShadow(color: Colors.black.withValues(alpha: 0.03), blurRadius: 8, offset: const Offset(0, 2))],
          ),
          child: Column(crossAxisAlignment: CrossAxisAlignment.start, children: [
            Row(children: [
              Container(width: 10, height: 10, decoration: BoxDecoration(
                color: _isActivated ? const Color(0xFF66BB6A) : const Color(0xFFDDDDDD), shape: BoxShape.circle)),
              const SizedBox(width: 10),
              Text(_isActivated ? '已激活' : '未激活',
                  style: TextStyle(fontSize: 16, fontWeight: FontWeight.w600,
                      color: _isActivated ? const Color(0xFF66BB6A) : const Color(0xFFBBBBBB))),
              const Spacer(),
              if (_isActivated)
                GestureDetector(
                  onTap: _disconnect,
                  child: Container(padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 5),
                      decoration: BoxDecoration(color: const Color(0xFFF5F5F5), borderRadius: BorderRadius.circular(6)),
                      child: const Text('断开', style: TextStyle(fontSize: 12, color: Color(0xFFE57373)))),
                ),
            ]),
            const SizedBox(height: 20),
            const Text('服务器地址', style: TextStyle(fontSize: 12, color: Color(0xFF999999))),
            const SizedBox(height: 6),
            TextField(controller: _urlController, style: const TextStyle(fontSize: 14, color: Color(0xFF1A1A1A)),
              decoration: _inputDeco('例: http://192.168.1.100:5000')),
            const SizedBox(height: 14),
            const Text('激活码', style: TextStyle(fontSize: 12, color: Color(0xFF999999))),
            const SizedBox(height: 6),
            TextField(controller: _codeController, style: const TextStyle(fontSize: 14, color: Color(0xFF1A1A1A)),
                textCapitalization: TextCapitalization.characters, decoration: _inputDeco('例: MK-A1B2C3D4E5F6')),
            const SizedBox(height: 16),
            SizedBox(width: double.infinity,
              child: ElevatedButton(
                onPressed: _isChecking ? null : _checkActivation,
                style: ElevatedButton.styleFrom(backgroundColor: const Color(0xFF1A1A1A), foregroundColor: Colors.white,
                    disabledBackgroundColor: const Color(0xFFDDDDDD), elevation: 0,
                    shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(10)),
                    padding: const EdgeInsets.symmetric(vertical: 13)),
                child: _isChecking
                    ? const SizedBox(width: 20, height: 20, child: CircularProgressIndicator(strokeWidth: 2, color: Colors.white))
                    : Text(_isActivated ? '重新验证' : '验证激活', style: const TextStyle(fontSize: 14, fontWeight: FontWeight.w600)),
              ),
            ),
            if (_expiresText.isNotEmpty) ...[
              const SizedBox(height: 12),
              Center(child: Row(mainAxisSize: MainAxisSize.min, children: [
                Icon(Icons.access_time, size: 14, color: _prefs.syncIsPermanent ? const Color(0xFF66BB6A) : const Color(0xFFFF9800)),
                const SizedBox(width: 6),
                Text(_expiresText, style: TextStyle(fontSize: 13, fontWeight: FontWeight.w500,
                    color: _prefs.syncIsPermanent ? const Color(0xFF66BB6A) : const Color(0xFFFF9800))),
              ])),
            ],
          ]),
        ),
        const SizedBox(height: 16),
        // 同步开关
        Container(
          padding: const EdgeInsets.all(20),
          decoration: BoxDecoration(color: Colors.white, borderRadius: BorderRadius.circular(16),
            boxShadow: [BoxShadow(color: Colors.black.withValues(alpha: 0.03), blurRadius: 8, offset: const Offset(0, 2))]),
          child: Row(children: [
            Container(width: 44, height: 44, decoration: BoxDecoration(color: const Color(0xFFF5F5F5), borderRadius: BorderRadius.circular(10)),
              child: Icon(_syncEnabled ? Icons.sync : Icons.sync_disabled,
                  color: _syncEnabled ? const Color(0xFF1A1A1A) : const Color(0xFFCCCCCC), size: 22)),
            const SizedBox(width: 14),
            Expanded(child: Column(crossAxisAlignment: CrossAxisAlignment.start, children: [
              const Text('服务端实时同步', style: TextStyle(fontSize: 15, fontWeight: FontWeight.w500, color: Color(0xFF1A1A1A))),
              const SizedBox(height: 2),
              Text(_syncEnabled ? '使用服务端数据，多设备实时共享' : '关闭后下载数据到本地使用',
                  style: const TextStyle(fontSize: 12, color: Color(0xFFBBBBBB))),
            ])),
            Switch(value: _syncEnabled, onChanged: _isActivated ? _toggleSync : null,
              activeColor: const Color(0xFF1A1A1A), activeTrackColor: const Color(0xFF1A1A1A).withOpacity(0.3),
              inactiveThumbColor: Colors.white, inactiveTrackColor: const Color(0xFFE5E5E5)),
          ]),
        ),
        const SizedBox(height: 24),
        // 说明
        Container(
          padding: const EdgeInsets.all(18),
          decoration: BoxDecoration(color: Colors.white, borderRadius: BorderRadius.circular(14),
            boxShadow: [BoxShadow(color: Colors.black.withValues(alpha: 0.03), blurRadius: 6, offset: const Offset(0, 2))]),
          child: Column(crossAxisAlignment: CrossAxisAlignment.start, children: [
            Row(children: [
              Container(width: 36, height: 36, decoration: BoxDecoration(color: const Color(0xFFF5F5F5), borderRadius: BorderRadius.circular(8)),
                  child: const Icon(Icons.info_outline, size: 18, color: Color(0xFF666666))),
              const SizedBox(width: 10),
              const Text('使用说明', style: TextStyle(fontSize: 14, fontWeight: FontWeight.w600, color: Color(0xFF1A1A1A))),
            ]),
            const SizedBox(height: 14),
            _infoItem('1. 在服务端管理后台生成激活码'),
            const SizedBox(height: 8),
            _infoItem('2. 输入服务器地址和激活码完成验证'),
            const SizedBox(height: 8),
            _infoItem('3. 验证通过后自动开启实时同步'),
            const SizedBox(height: 8),
            _infoItem('4. 开启时所有数据通过服务端接口操作'),
            const SizedBox(height: 8),
            _infoItem('5. 关闭时从服务端下载数据到本地使用'),
          ]),
        ),
        const SizedBox(height: 40),
      ]),
    );
  }

  InputDecoration _inputDeco(String hint) {
    return InputDecoration(
      hintText: hint, hintStyle: const TextStyle(fontSize: 13, color: Color(0xFFCCCCCC)),
      filled: true, fillColor: const Color(0xFFF8F8F8),
      contentPadding: const EdgeInsets.symmetric(horizontal: 14, vertical: 12),
      border: OutlineInputBorder(borderRadius: BorderRadius.circular(10), borderSide: BorderSide.none),
      focusedBorder: OutlineInputBorder(borderRadius: BorderRadius.circular(10), borderSide: const BorderSide(color: Color(0xFF1A1A1A), width: 1)),
    );
  }

  Widget _infoItem(String text) {
    return Row(crossAxisAlignment: CrossAxisAlignment.start, children: [
      Container(width: 5, height: 5, margin: const EdgeInsets.only(top: 6), decoration: BoxDecoration(color: const Color(0xFFBBBBBB), shape: BoxShape.circle)),
      const SizedBox(width: 10),
      Expanded(child: Text(text, style: const TextStyle(fontSize: 13, color: Color(0xFF888888), height: 1.5))),
    ]);
  }
}