import 'dart:async';
import 'package:flutter/material.dart';
import 'package:provider/provider.dart';
import 'package:superport/models/user_model.dart';
import 'package:superport/screens/common/theme_shadcn.dart';
import 'package:superport/screens/common/components/shadcn_components.dart';
import 'package:superport/screens/common/widgets/pagination.dart';
import 'package:superport/screens/user/controllers/user_list_controller.dart';
import 'package:superport/utils/constants.dart';
import 'package:superport/services/mock_data_service.dart';
import 'package:superport/utils/user_utils.dart';

/// shadcn/ui 스타일로 재설계된 사용자 관리 화면
class UserListRedesign extends StatefulWidget {
  const UserListRedesign({super.key});

  @override
  State<UserListRedesign> createState() => _UserListRedesignState();
}

class _UserListRedesignState extends State<UserListRedesign> {
  final MockDataService _dataService = MockDataService();
  final TextEditingController _searchController = TextEditingController();
  int _currentPage = 1;
  final int _pageSize = 10;
  
  @override
  void initState() {
    super.initState();
    
    // 초기 데이터 로드
    WidgetsBinding.instance.addPostFrameCallback((_) {
      context.read<UserListController>().loadUsers();
    });
    
    // 검색 디바운싱
    _searchController.addListener(() {
      _onSearchChanged(_searchController.text);
    });
  }

  @override
  void dispose() {
    _searchController.dispose();
    super.dispose();
  }
  
  
  /// 검색어 변경 처리 (디바운싱)
  Timer? _debounce;
  void _onSearchChanged(String query) {
    if (_debounce?.isActive ?? false) _debounce!.cancel();
    _debounce = Timer(const Duration(milliseconds: 300), () {
      setState(() {
        _currentPage = 1;
      });
      context.read<UserListController>().setSearchQuery(query);
    });
  }

  /// 회사명 반환 함수
  String _getCompanyName(int companyId) {
    final company = _dataService.getCompanyById(companyId);
    return company?.name ?? '-';
  }
  
  /// 상태별 색상 반환
  Color _getStatusColor(bool isActive) {
    return isActive ? Colors.green : Colors.red;
  }

  /// 사용자 권한 표시 배지
  Widget _buildUserRoleBadge(String role) {
    final roleName = getRoleName(role);
    ShadcnBadgeVariant variant;
    
    switch (role) {
      case 'S':
        variant = ShadcnBadgeVariant.destructive;
        break;
      case 'M':
        variant = ShadcnBadgeVariant.primary;
        break;
      default:
        variant = ShadcnBadgeVariant.outline;
    }
    
    return ShadcnBadge(
      text: roleName,
      variant: variant,
      size: ShadcnBadgeSize.small,
    );
  }

  /// 사용자 추가 폼으로 이동
  void _navigateToAdd() async {
    final result = await Navigator.pushNamed(context, Routes.userAdd);
    if (result == true && mounted) {
      context.read<UserListController>().loadUsers(refresh: true);
    }
  }

  /// 사용자 수정 폼으로 이동
  void _navigateToEdit(int userId) async {
    final result = await Navigator.pushNamed(
      context,
      Routes.userEdit,
      arguments: userId,
    );
    if (result == true && mounted) {
      context.read<UserListController>().loadUsers(refresh: true);
    }
  }

  /// 사용자 삭제 다이얼로그
  void _showDeleteDialog(int userId, String userName) {
    showDialog(
      context: context,
      builder: (context) => AlertDialog(
        title: const Text('사용자 삭제'),
        content: Text('"$userName" 사용자를 정말로 삭제하시겠습니까?'),
        actions: [
          TextButton(
            onPressed: () => Navigator.of(context).pop(),
            child: const Text('취소'),
          ),
          TextButton(
            onPressed: () async {
              Navigator.of(context).pop();
              
              await context.read<UserListController>().deleteUser(
                userId,
                () {
                  ScaffoldMessenger.of(context).showSnackBar(
                    const SnackBar(content: Text('사용자가 삭제되었습니다')),
                  );
                },
                (error) {
                  ScaffoldMessenger.of(context).showSnackBar(
                    SnackBar(content: Text(error), backgroundColor: Colors.red),
                  );
                },
              );
            },
            child: const Text('삭제', style: TextStyle(color: Colors.red)),
          ),
        ],
      ),
    );
  }
  
  /// 상태 변경 확인 다이얼로그
  void _showStatusChangeDialog(User user) {
    final newStatus = !user.isActive;
    final statusText = newStatus ? '활성화' : '비활성화';
    
    showDialog(
      context: context,
      builder: (context) => AlertDialog(
        title: Text('사용자 상태 변경'),
        content: Text('"${user.name}" 사용자를 $statusText 하시겠습니까?'),
        actions: [
          TextButton(
            onPressed: () => Navigator.of(context).pop(),
            child: const Text('취소'),
          ),
          TextButton(
            onPressed: () async {
              Navigator.of(context).pop();
              
              await context.read<UserListController>().changeUserStatus(
                user.id!,
                newStatus,
                (error) {
                  ScaffoldMessenger.of(context).showSnackBar(
                    SnackBar(content: Text(error), backgroundColor: Colors.red),
                  );
                },
              );
            },
            child: Text(statusText),
          ),
        ],
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return ChangeNotifierProvider(
      create: (_) => UserListController(dataService: _dataService),
      child: Consumer<UserListController>(
        builder: (context, controller, child) {
          if (controller.isLoading && controller.users.isEmpty) {
            return const Center(
              child: CircularProgressIndicator(),
            );
          }
          
          if (controller.error != null && controller.users.isEmpty) {
            return Center(
              child: Column(
                mainAxisAlignment: MainAxisAlignment.center,
                children: [
                  Icon(Icons.error_outline, size: 64, color: Colors.red[300]),
                  const SizedBox(height: 16),
                  Text(
                    '데이터를 불러올 수 없습니다',
                    style: ShadcnTheme.headingH4,
                  ),
                  const SizedBox(height: 8),
                  Text(
                    controller.error!,
                    style: ShadcnTheme.bodyMuted,
                    textAlign: TextAlign.center,
                  ),
                  const SizedBox(height: 16),
                  ShadcnButton(
                    text: '다시 시도',
                    onPressed: () => controller.loadUsers(refresh: true),
                    variant: ShadcnButtonVariant.primary,
                  ),
                ],
              ),
            );
          }
          
          // 페이지네이션을 위한 데이터 처리
          final int totalUsers = controller.users.length;
          final int startIndex = (_currentPage - 1) * _pageSize;
          final int endIndex = startIndex + _pageSize;
          final List<User> pagedUsers = controller.users.sublist(
            startIndex,
            endIndex > totalUsers ? totalUsers : endIndex,
          );
          
          return SingleChildScrollView(
            padding: const EdgeInsets.all(ShadcnTheme.spacing6),
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                // 검색 및 필터 섹션
                Card(
                  elevation: 0,
                  shape: RoundedRectangleBorder(
                    borderRadius: BorderRadius.circular(ShadcnTheme.radiusMd),
                    side: BorderSide(color: Colors.black),
                  ),
                  child: Padding(
                    padding: const EdgeInsets.all(ShadcnTheme.spacing4),
                    child: Column(
                      children: [
                        // 검색 바
                        TextField(
                          controller: _searchController,
                          decoration: InputDecoration(
                            hintText: '이름, 이메일, 사용자명으로 검색...',
                            prefixIcon: const Icon(Icons.search),
                            suffixIcon: _searchController.text.isNotEmpty
                                ? IconButton(
                                    icon: const Icon(Icons.clear),
                                    onPressed: () {
                                      _searchController.clear();
                                      controller.setSearchQuery('');
                                    },
                                  )
                                : null,
                            border: OutlineInputBorder(
                              borderRadius: BorderRadius.circular(ShadcnTheme.radiusMd),
                            ),
                            contentPadding: const EdgeInsets.symmetric(
                              horizontal: ShadcnTheme.spacing4,
                              vertical: ShadcnTheme.spacing3,
                            ),
                          ),
                        ),
                        const SizedBox(height: ShadcnTheme.spacing3),
                        // 필터 버튼들
                        Row(
                          children: [
                            // 상태 필터
                            ShadcnButton(
                              text: controller.filterIsActive == null
                                  ? '모든 상태'
                                  : controller.filterIsActive!
                                      ? '활성 사용자'
                                      : '비활성 사용자',
                              onPressed: () {
                                controller.setFilters(
                                  isActive: controller.filterIsActive == null
                                      ? true
                                      : controller.filterIsActive!
                                          ? false
                                          : null,
                                );
                              },
                              variant: ShadcnButtonVariant.secondary,
                              icon: const Icon(Icons.filter_list),
                            ),
                            const SizedBox(width: ShadcnTheme.spacing2),
                            // 권한 필터
                            PopupMenuButton<String?>(
                              child: ShadcnButton(
                                text: controller.filterRole == null
                                    ? '모든 권한'
                                    : getRoleName(controller.filterRole!),
                                onPressed: null,
                                variant: ShadcnButtonVariant.secondary,
                                icon: const Icon(Icons.person),
                              ),
                              onSelected: (role) {
                                controller.setFilters(role: role);
                              },
                              itemBuilder: (context) => [
                                const PopupMenuItem(
                                  value: null,
                                  child: Text('모든 권한'),
                                ),
                                const PopupMenuItem(
                                  value: 'S',
                                  child: Text('관리자'),
                                ),
                                const PopupMenuItem(
                                  value: 'M',
                                  child: Text('멤버'),
                                ),
                              ],
                            ),
                            const Spacer(),
                            // 필터 초기화
                            if (controller.searchQuery.isNotEmpty ||
                                controller.filterIsActive != null ||
                                controller.filterRole != null)
                              ShadcnButton(
                                text: '필터 초기화',
                                onPressed: () {
                                  _searchController.clear();
                                  controller.clearFilters();
                                },
                                variant: ShadcnButtonVariant.ghost,
                                icon: const Icon(Icons.clear_all),
                              ),
                          ],
                        ),
                      ],
                    ),
                  ),
                ),
                
                const SizedBox(height: ShadcnTheme.spacing4),
                
                // 헤더 액션 바
                Row(
                  mainAxisAlignment: MainAxisAlignment.spaceBetween,
                  children: [
                    Text(
                      '총 ${controller.users.length}명 사용자',
                      style: ShadcnTheme.bodyMuted,
                    ),
                    Row(
                      children: [
                        ShadcnButton(
                          text: '새로고침',
                          onPressed: () => controller.loadUsers(refresh: true),
                          variant: ShadcnButtonVariant.secondary,
                          icon: const Icon(Icons.refresh),
                        ),
                        const SizedBox(width: ShadcnTheme.spacing2),
                        ShadcnButton(
                          text: '사용자 추가',
                          onPressed: _navigateToAdd,
                          variant: ShadcnButtonVariant.primary,
                          textColor: Colors.white,
                          icon: const Icon(Icons.add),
                        ),
                      ],
                    ),
                  ],
                ),

                const SizedBox(height: ShadcnTheme.spacing4),

                // 테이블 컨테이너
                Container(
                  width: double.infinity,
                  decoration: BoxDecoration(
                    border: Border.all(color: Colors.black),
                    borderRadius: BorderRadius.circular(ShadcnTheme.radiusMd),
                  ),
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      // 테이블 헤더
                      Container(
                        padding: const EdgeInsets.symmetric(
                          horizontal: ShadcnTheme.spacing4,
                          vertical: ShadcnTheme.spacing3,
                        ),
                        decoration: BoxDecoration(
                          color: ShadcnTheme.muted.withValues(alpha: 0.3),
                          border: Border(
                            bottom: BorderSide(color: Colors.black),
                          ),
                        ),
                        child: Row(
                          children: [
                            const SizedBox(width: 50, child: Text('번호', style: TextStyle(fontWeight: FontWeight.bold))),
                            const Expanded(flex: 2, child: Text('사용자명', style: TextStyle(fontWeight: FontWeight.bold))),
                            const Expanded(flex: 2, child: Text('이메일', style: TextStyle(fontWeight: FontWeight.bold))),
                            const Expanded(flex: 2, child: Text('회사명', style: TextStyle(fontWeight: FontWeight.bold))),
                            const Expanded(flex: 2, child: Text('지점명', style: TextStyle(fontWeight: FontWeight.bold))),
                            const SizedBox(width: 100, child: Text('권한', style: TextStyle(fontWeight: FontWeight.bold))),
                            const SizedBox(width: 80, child: Text('상태', style: TextStyle(fontWeight: FontWeight.bold))),
                            const SizedBox(width: 120, child: Text('관리', style: TextStyle(fontWeight: FontWeight.bold))),
                          ],
                        ),
                      ),

                      // 테이블 데이터
                      if (controller.users.isEmpty)
                        Container(
                          padding: const EdgeInsets.all(ShadcnTheme.spacing8),
                          child: Center(
                            child: Text(
                              controller.searchQuery.isNotEmpty || 
                              controller.filterIsActive != null || 
                              controller.filterRole != null
                                  ? '검색 결과가 없습니다.'
                                  : '등록된 사용자가 없습니다.',
                              style: ShadcnTheme.bodyMuted,
                            ),
                          ),
                        )
                      else
                        ...pagedUsers.asMap().entries.map((entry) {
                          final int index = startIndex + entry.key;
                          final User user = entry.value;

                          return Container(
                            padding: const EdgeInsets.all(ShadcnTheme.spacing4),
                            decoration: BoxDecoration(
                              border: Border(
                                bottom: BorderSide(color: Colors.black),
                              ),
                              color: index % 2 == 0 ? null : ShadcnTheme.muted.withValues(alpha: 0.1),
                            ),
                            child: Row(
                              children: [
                                // 번호
                                SizedBox(
                                  width: 50,
                                  child: Text(
                                    '${index + 1}',
                                    style: ShadcnTheme.bodySmall,
                                  ),
                                ),
                                // 사용자명
                                Expanded(
                                  flex: 2,
                                  child: Column(
                                    crossAxisAlignment: CrossAxisAlignment.start,
                                    children: [
                                      Text(
                                        user.name,
                                        style: ShadcnTheme.bodyMedium,
                                      ),
                                      if (user.username != null)
                                        Text(
                                          '@${user.username}',
                                          style: ShadcnTheme.bodySmall.copyWith(
                                            color: ShadcnTheme.muted,
                                          ),
                                        ),
                                    ],
                                  ),
                                ),
                                // 이메일
                                Expanded(
                                  flex: 2,
                                  child: Text(
                                    user.email ?? '미등록',
                                    style: ShadcnTheme.bodySmall,
                                  ),
                                ),
                                // 회사명
                                Expanded(
                                  flex: 2,
                                  child: Text(
                                    _getCompanyName(user.companyId),
                                    style: ShadcnTheme.bodySmall,
                                  ),
                                ),
                                // 지점명
                                Expanded(
                                  flex: 2,
                                  child: Text(
                                    controller.getBranchName(
                                      user.companyId,
                                      user.branchId,
                                    ),
                                    style: ShadcnTheme.bodySmall,
                                  ),
                                ),
                                // 권한
                                SizedBox(
                                  width: 100,
                                  child: _buildUserRoleBadge(user.role),
                                ),
                                // 상태
                                SizedBox(
                                  width: 80,
                                  child: Row(
                                    children: [
                                      Icon(
                                        Icons.circle,
                                        size: 8,
                                        color: _getStatusColor(user.isActive),
                                      ),
                                      const SizedBox(width: 4),
                                      Text(
                                        user.isActive ? '활성' : '비활성',
                                        style: ShadcnTheme.bodySmall.copyWith(
                                          color: _getStatusColor(user.isActive),
                                        ),
                                      ),
                                    ],
                                  ),
                                ),
                                // 관리
                                SizedBox(
                                  width: 120,
                                  child: Row(
                                    mainAxisSize: MainAxisSize.min,
                                    children: [
                                      Flexible(
                                        child: IconButton(
                                          constraints: const BoxConstraints(
                                            minWidth: 30,
                                            minHeight: 30,
                                          ),
                                          padding: const EdgeInsets.all(4),
                                          icon: Icon(
                                            Icons.power_settings_new,
                                            size: 16,
                                            color: user.isActive ? Colors.orange : Colors.green,
                                          ),
                                          onPressed: user.id != null
                                              ? () => _showStatusChangeDialog(user)
                                              : null,
                                          tooltip: user.isActive ? '비활성화' : '활성화',
                                        ),
                                      ),
                                      Flexible(
                                        child: IconButton(
                                          constraints: const BoxConstraints(
                                            minWidth: 30,
                                            minHeight: 30,
                                          ),
                                          padding: const EdgeInsets.all(4),
                                          icon: Icon(
                                            Icons.edit,
                                            size: 16,
                                            color: ShadcnTheme.primary,
                                          ),
                                          onPressed: user.id != null
                                              ? () => _navigateToEdit(user.id!)
                                              : null,
                                          tooltip: '수정',
                                        ),
                                      ),
                                      Flexible(
                                        child: IconButton(
                                          constraints: const BoxConstraints(
                                            minWidth: 30,
                                            minHeight: 30,
                                          ),
                                          padding: const EdgeInsets.all(4),
                                          icon: Icon(
                                            Icons.delete,
                                            size: 16,
                                            color: ShadcnTheme.destructive,
                                          ),
                                          onPressed: user.id != null
                                              ? () => _showDeleteDialog(user.id!, user.name)
                                              : null,
                                          tooltip: '삭제',
                                        ),
                                      ),
                                    ],
                                  ),
                                ),
                              ],
                            ),
                          );
                        }),
                    ],
                  ),
                ),
                
                // 페이지네이션 컴포넌트
                if (totalUsers > _pageSize)
                  Pagination(
                    totalCount: totalUsers,
                    currentPage: _currentPage,
                    pageSize: _pageSize,
                    onPageChanged: (page) {
                      setState(() {
                        _currentPage = page;
                      });
                    },
                  ),
              ],
            ),
          );
        },
      ),
    );
  }
}