import 'package:flutter/material.dart';
import 'package:provider/provider.dart';
import 'package:get_it/get_it.dart';
import 'package:shadcn_ui/shadcn_ui.dart';
import 'package:superport/screens/common/theme_shadcn.dart';
import 'package:superport/screens/common/widgets/pagination.dart';
import 'package:superport/screens/common/widgets/standard_action_bar.dart';
import 'package:superport/screens/common/widgets/standard_states.dart';
import 'package:superport/screens/maintenance/controllers/maintenance_controller.dart';
import 'package:superport/screens/maintenance/maintenance_form_dialog.dart';
import 'package:superport/data/models/maintenance_dto.dart';
import 'package:superport/data/repositories/equipment_history_repository.dart';
import 'package:superport/domain/usecases/maintenance_usecase.dart';

/// shadcn/ui 스타일로 설계된 유지보수 관리 화면
class MaintenanceList extends StatefulWidget {
  const MaintenanceList({super.key});

  @override
  State<MaintenanceList> createState() => _MaintenanceListState();
}

class _MaintenanceListState extends State<MaintenanceList> {
  late final MaintenanceController _controller;
  bool _showDetailedColumns = true;
  final TextEditingController _searchController = TextEditingController();
  final ScrollController _horizontalScrollController = ScrollController();
  final Set<int> _selectedItems = {};

  @override
  void initState() {
    super.initState();
    _controller = MaintenanceController(
      maintenanceUseCase: GetIt.instance<MaintenanceUseCase>(),
      equipmentHistoryRepository: GetIt.instance<EquipmentHistoryRepository>(),
    );
    
    // 초기 데이터 로드
    WidgetsBinding.instance.addPostFrameCallback((_) {
      _controller.loadMaintenances(refresh: true);
      _controller.loadExpiringMaintenances();
    });
  }

  @override
  void dispose() {
    _searchController.dispose();
    _horizontalScrollController.dispose();
    _controller.dispose();
    super.dispose();
  }

  @override
  void didChangeDependencies() {
    super.didChangeDependencies();
    _adjustColumnsForScreenSize();
  }

  /// 화면 크기에 따라 컬럼 표시 조정
  void _adjustColumnsForScreenSize() {
    final width = MediaQuery.of(context).size.width;
    setState(() {
      _showDetailedColumns = width > 1000;
    });
  }

  @override
  Widget build(BuildContext context) {
    return ChangeNotifierProvider.value(
      value: _controller,
      child: Scaffold(
        backgroundColor: ShadcnTheme.background,
        body: Consumer<MaintenanceController>(
          builder: (context, controller, child) {
            return Column(
              children: [
                _buildActionBar(),
                _buildFilterBar(),
                Expanded(child: _buildMainContent()),
                Container(
                  padding: const EdgeInsets.all(ShadcnTheme.spacing4),
                  decoration: BoxDecoration(
                    color: ShadcnTheme.card,
                    border: Border(
                      top: BorderSide(color: ShadcnTheme.border),
                    ),
                  ),
                  child: _buildPagination(controller),
                ),
              ],
            );
          },
        ),
      ),
    );
  }

  /// 상단 액션바
  Widget _buildActionBar() {
    return Consumer<MaintenanceController>(
      builder: (context, controller, child) {
        return StandardActionBar(
          totalCount: controller.totalCount,
          selectedCount: _selectedItems.length,
          leftActions: const [
            Text('유지보수 관리', style: TextStyle(fontSize: 18, fontWeight: FontWeight.bold)),
          ],
          rightActions: [
            // 만료 예정 알림
            if (controller.expiringMaintenances.isNotEmpty)
              ShadButton.outline(
                child: Row(
                  mainAxisSize: MainAxisSize.min,
                  children: [
                    const Icon(Icons.notification_important, size: 16),
                    const SizedBox(width: 4),
                    Text('만료 예정 ${controller.expiringMaintenances.length}건'),
                  ],
                ),
                onPressed: () => _showExpiringMaintenances(),
              ),
            
            // 새로운 유지보수 등록
            ShadButton(
              child: const Row(
                mainAxisSize: MainAxisSize.min,
                children: [
                  Icon(Icons.add, size: 16),
                  SizedBox(width: 4),
                  Text('유지보수 등록'),
                ],
              ),
              onPressed: () => _showMaintenanceForm(),
            ),
            
            // 선택된 항목 삭제
            if (_selectedItems.isNotEmpty)
              ShadButton.destructive(
                child: Row(
                  mainAxisSize: MainAxisSize.min,
                  children: [
                    const Icon(Icons.delete, size: 16),
                    const SizedBox(width: 4),
                    Text('삭제 (${_selectedItems.length})'),
                  ],
                ),
                onPressed: () => _showDeleteConfirmation(),
              ),
          ],
        );
      },
    );
  }

  /// 필터바
  Widget _buildFilterBar() {
    return Container(
      padding: const EdgeInsets.all(16),
      decoration: BoxDecoration(
        color: ShadcnTheme.card,
        border: Border(
          bottom: BorderSide(color: ShadcnTheme.border),
        ),
      ),
      child: Row(
        children: [
          // 유지보수 타입 필터
          Expanded(
            flex: 2,
            child: ShadSelect<String>(
              placeholder: const Text('유지보수 타입'),
              options: [
                const ShadOption(value: 'all', child: Text('전체')),
                ...MaintenanceType.typeOptions.map((option) =>
                  ShadOption(
                    value: option['value']!,
                    child: Text(option['label']!),
                  ),
                ),
              ],
              selectedOptionBuilder: (context, value) {
                if (value == 'all') return const Text('전체');
                final option = MaintenanceType.typeOptions
                    .firstWhere((o) => o['value'] == value, orElse: () => {'label': value});
                return Text(option['label']!);
              },
              onChanged: (value) {
                _controller.setMaintenanceTypeFilter(
                  value == 'all' ? null : value,
                );
              },
            ),
          ),
          
          const SizedBox(width: 12),
          
          // 상태 필터
          Expanded(
            flex: 2,
            child: ShadSelect<String>(
              placeholder: const Text('상태'),
              options: const [
                ShadOption(value: 'all', child: Text('전체')),
                ShadOption(value: 'active', child: Text('활성')),
                ShadOption(value: 'expired', child: Text('만료')),
                ShadOption(value: 'expiring', child: Text('만료 예정')),
              ],
              selectedOptionBuilder: (context, value) {
                switch (value) {
                  case 'active': return const Text('활성');
                  case 'expired': return const Text('만료');
                  case 'expiring': return const Text('만료 예정');
                  default: return const Text('전체');
                }
              },
              onChanged: (value) {
                _applyStatusFilter(value ?? 'all');
              },
            ),
          ),
          
          const SizedBox(width: 12),
          
          // 검색
          Expanded(
            flex: 3,
            child: ShadInput(
              controller: _searchController,
              placeholder: const Text('장비 시리얼 번호 또는 모델명 검색...'),
              onSubmitted: (_) => _performSearch(),
            ),
          ),
          
          const SizedBox(width: 12),
          
          // 필터 초기화
          ShadButton.outline(
            child: const Icon(Icons.refresh, size: 16),
            onPressed: _resetFilters,
          ),
        ],
      ),
    );
  }

  /// 메인 컨텐츠
  Widget _buildMainContent() {
    return Consumer<MaintenanceController>(
      builder: (context, controller, child) {
        if (controller.isLoading && controller.maintenances.isEmpty) {
          return const StandardLoadingState(message: '유지보수 목록을 불러오는 중...');
        }

        if (controller.error != null) {
          return StandardErrorState(
            message: controller.error!,
            onRetry: () => controller.loadMaintenances(refresh: true),
          );
        }

        if (controller.maintenances.isEmpty) {
          return const StandardEmptyState(
            icon: Icons.build_circle_outlined,
            title: '유지보수가 없습니다',
            message: '새로운 유지보수를 등록해보세요.',
          );
        }

        return _buildDataTable(controller);
      },
    );
  }

  /// 데이터 테이블
  Widget _buildDataTable(MaintenanceController controller) {
    final maintenances = controller.maintenances;

    if (maintenances.isEmpty) {
      return const StandardEmptyState(
        icon: Icons.build_circle_outlined,
        title: '유지보수가 없습니다',
        message: '새로운 유지보수를 등록해보세요.',
      );
    }

    return LayoutBuilder(
      builder: (context, constraints) {
        // 기본 컬럼 폭 합산
        const double selectW = 60;
        const double idW = 80;
        const double equipInfoBaseW = 200; // 이 컬럼이 남는 폭을 흡수
        const double typeW = 120;
        const double startW = 100;
        const double endW = 100;
        const double periodW = 80;
        const double statusW = 100;
        const double remainW = 100;
        const double actionsW = 120;

        double baseWidth = selectW + idW + equipInfoBaseW + typeW + startW + endW + actionsW;
        if (_showDetailedColumns) {
          baseWidth += periodW + statusW + remainW;
        }

        final extra = (constraints.maxWidth - baseWidth);
        final double equipInfoWidth = equipInfoBaseW + (extra > 0 ? extra : 0.0);
        final double tableWidth = (constraints.maxWidth > baseWidth) ? constraints.maxWidth : baseWidth;

        return Container(
          decoration: BoxDecoration(
            border: Border.all(color: ShadcnTheme.border),
            borderRadius: BorderRadius.circular(ShadcnTheme.radiusMd),
          ),
          child: Column(
            children: [
              // 고정 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: ShadcnTheme.border)),
                  borderRadius: BorderRadius.only(
                    topLeft: Radius.circular(ShadcnTheme.radiusMd),
                    topRight: Radius.circular(ShadcnTheme.radiusMd),
                  ),
                ),
                child: SingleChildScrollView(
                  scrollDirection: Axis.horizontal,
                  controller: _horizontalScrollController,
                  child: _buildFixedHeader(equipInfoWidth, tableWidth),
                ),
              ),

              // 스크롤 가능한 바디
              Expanded(
                child: SingleChildScrollView(
                  scrollDirection: Axis.horizontal,
                  controller: _horizontalScrollController,
                  child: SizedBox(
                    width: tableWidth,
                    child: ListView.builder(
                      itemCount: maintenances.length,
                      itemBuilder: (context, index) => _buildTableRow(maintenances[index], index, equipInfoWidth),
                    ),
                  ),
                ),
              ),
            ],
          ),
        );
      },
    );
  }

  /// 고정 헤더 빌드
  Widget _buildFixedHeader(double equipInfoWidth, double tableWidth) {
    return SizedBox(
      width: tableWidth,
      child: Row(
        children: [
          _buildHeaderCell('선택', 60),
          _buildHeaderCell('ID', 80),
          _buildHeaderCell('장비 정보', equipInfoWidth),
          _buildHeaderCell('유지보수 타입', 120),
          _buildHeaderCell('시작일', 100),
          _buildHeaderCell('종료일', 100),
          if (_showDetailedColumns) ...[
            _buildHeaderCell('주기', 80),
            _buildHeaderCell('상태', 100),
            _buildHeaderCell('남은 일수', 100),
          ],
          _buildHeaderCell('작업', 120),
        ],
      ),
    );
  }

  // 기존 _calculateTableWidth 제거: LayoutBuilder에서 계산

  /// 헤더 셀 빌드
  Widget _buildHeaderCell(String text, double width) {
    return Container(
      width: width,
      padding: const EdgeInsets.symmetric(horizontal: ShadcnTheme.spacing2),
      child: Text(
        text,
        style: ShadcnTheme.bodyMedium.copyWith(fontWeight: FontWeight.w500),
      ),
    );
  }

  /// 테이블 행 빌드
  Widget _buildTableRow(MaintenanceDto maintenance, int index, double equipInfoWidth) {
    return Container(
      decoration: BoxDecoration(
        color: index.isEven ? ShadcnTheme.muted.withValues(alpha: 0.1) : null,
        border: Border(bottom: BorderSide(color: ShadcnTheme.border.withValues(alpha: 0.3))),
      ),
      child: Material(
        color: Colors.transparent,
        child: InkWell(
          onTap: () => _showMaintenanceDetail(maintenance),
          child: Container(
            padding: const EdgeInsets.symmetric(horizontal: ShadcnTheme.spacing4, vertical: ShadcnTheme.spacing3),
            child: Row(
              children: [
                // 선택 체크박스
                SizedBox(
                  width: 60,
                  child: ShadCheckbox(
                    value: _selectedItems.contains(maintenance.id),
                    onChanged: (value) {
                      setState(() {
                        if (value == true) {
                          _selectedItems.add(maintenance.id!);
                        } else {
                          _selectedItems.remove(maintenance.id!);
                        }
                      });
                    },
                  ),
                ),

                // ID
                SizedBox(
                  width: 80,
                  child: Text(
                    maintenance.id?.toString() ?? '-',
                    style: ShadcnTheme.bodySmall,
                  ),
                ),

                // 장비 정보 (가변 폭)
                SizedBox(
                  width: equipInfoWidth,
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    mainAxisSize: MainAxisSize.min,
                    children: [
                      Text(
                        maintenance.equipmentSerial ?? '시리얼 번호 없음',
                        style: const TextStyle(fontWeight: FontWeight.w500),
                        overflow: TextOverflow.ellipsis,
                      ),
                      if (maintenance.equipmentModel != null)
                        Text(
                          maintenance.equipmentModel!,
                          style: TextStyle(
                            fontSize: 12,
                            color: ShadcnTheme.mutedForeground,
                          ),
                          overflow: TextOverflow.ellipsis,
                        ),
                    ],
                  ),
                ),

                // 유지보수 타입
                SizedBox(
                  width: 120,
                  child: Container(
                    padding: const EdgeInsets.symmetric(horizontal: ShadcnTheme.spacing2, vertical: ShadcnTheme.spacing1),
                    decoration: BoxDecoration(
                      color: _getMaintenanceTypeColor(maintenance.maintenanceType),
                      borderRadius: BorderRadius.circular(ShadcnTheme.radiusSm),
                    ),
                    child: Text(
                      MaintenanceType.getDisplayName(maintenance.maintenanceType),
                      style: ShadcnTheme.caption.copyWith(
                        fontSize: 12,
                        color: ShadcnTheme.primaryForeground,
                        fontWeight: FontWeight.w500,
                      ),
                      overflow: TextOverflow.ellipsis,
                    ),
                  ),
                ),

                // 시작일
                SizedBox(
                  width: 100,
                  child: Text(
                    DateFormat('yyyy-MM-dd').format(maintenance.startedAt),
                    style: ShadcnTheme.bodySmall,
                  ),
                ),

                // 종료일
                SizedBox(
                  width: 100,
                  child: Text(
                    DateFormat('yyyy-MM-dd').format(maintenance.endedAt),
                    style: ShadcnTheme.bodySmall,
                  ),
                ),

                // 상세 컬럼들
                if (_showDetailedColumns) ...[
                  // 주기
                  SizedBox(
                    width: 80,
                    child: Text(
                      '${maintenance.periodMonth}개월',
                      style: ShadcnTheme.bodySmall,
                    ),
                  ),

                  // 상태
                  SizedBox(
                    width: 100,
                    child: Container(
                      padding: const EdgeInsets.symmetric(horizontal: ShadcnTheme.spacing2, vertical: ShadcnTheme.spacing1),
                      decoration: BoxDecoration(
                        color: _controller.getMaintenanceStatusColor(maintenance),
                        borderRadius: BorderRadius.circular(ShadcnTheme.radiusSm),
                      ),
                      child: Text(
                        _controller.getMaintenanceStatusText(maintenance),
                        style: ShadcnTheme.caption.copyWith(
                          fontSize: 12,
                          color: ShadcnTheme.primaryForeground,
                          fontWeight: FontWeight.w500,
                        ),
                        overflow: TextOverflow.ellipsis,
                      ),
                    ),
                  ),

                  // 남은 일수
                  SizedBox(
                    width: 100,
                    child: Text(
                      maintenance.daysRemaining != null
                          ? '${maintenance.daysRemaining}일'
                          : '-',
                      style: TextStyle(
                        color: maintenance.daysRemaining != null &&
                               maintenance.daysRemaining! <= 30
                            ? ShadcnTheme.destructive
                            : ShadcnTheme.foreground,
                      ),
                    ),
                  ),
                ],

                // 작업 버튼들
                SizedBox(
                  width: 120,
                  child: Row(
                    mainAxisSize: MainAxisSize.min,
                    children: [
                      ShadButton.ghost(
                        child: const Icon(Icons.edit, size: 16),
                        onPressed: () => _showMaintenanceForm(maintenance: maintenance),
                      ),
                      const SizedBox(width: ShadcnTheme.spacing1),
                      ShadButton.ghost(
                        child: Icon(
                          Icons.delete,
                          size: 16,
                          color: ShadcnTheme.destructive,
                        ),
                        onPressed: () => _deleteMaintenance(maintenance),
                      ),
                    ],
                  ),
                ),
              ],
            ),
          ),
        ),
      ),
    );
  }

  /// 하단 페이지네이션
  Widget _buildPagination(MaintenanceController controller) {
    return Pagination(
      totalCount: controller.totalCount,
      currentPage: controller.currentPage,
      pageSize: 20, // MaintenanceController._perPage 상수값
      onPageChanged: (page) => controller.goToPage(page),
    );
  }


  // 유틸리티 메서드들
  Color _getMaintenanceTypeColor(String type) {
    switch (type) {
      case MaintenanceType.visit:
        return Colors.blue;
      case MaintenanceType.remote:
        return Colors.green;
      default:
        return Colors.grey;
    }
  }

  void _applyStatusFilter(String status) {
    switch (status) {
      case 'active':
        _controller.setExpiredFilter(false);
        break;
      case 'expired':
        _controller.setExpiredFilter(true);
        break;
      case 'expiring':
        _controller.setExpiringDaysFilter(30);
        break;
      default:
        _controller.setExpiredFilter(null);
        _controller.setExpiringDaysFilter(null);
    }
  }

  void _performSearch() {
    // TODO: 장비 시리얼/모델 검색 구현
    // 백엔드에 검색 API가 추가되면 구현
  }

  void _resetFilters() {
    setState(() {
      _searchController.clear();
    });
    _controller.clearFilters();
  }

  // 다이얼로그 메서드들
  void _showMaintenanceForm({MaintenanceDto? maintenance}) {
    showDialog(
      context: context,
      builder: (context) => ChangeNotifierProvider.value(
        value: _controller,
        child: MaintenanceFormDialog(maintenance: maintenance),
      ),
    ).then((_) {
      // 폼 닫힌 후 목록 새로고침
      _controller.loadMaintenances(refresh: true);
    });
  }

  void _showMaintenanceDetail(MaintenanceDto maintenance) {
    _controller.selectMaintenance(maintenance);
    _showMaintenanceForm(maintenance: maintenance);
  }

  void _showExpiringMaintenances() {
    showDialog(
      context: context,
      builder: (context) => AlertDialog(
        title: const Text('만료 예정 유지보수'),
        content: SizedBox(
          width: 600,
          height: 400,
          child: ListView.builder(
            itemCount: _controller.expiringMaintenances.length,
            itemBuilder: (context, index) {
              final maintenance = _controller.expiringMaintenances[index];
              return ListTile(
                title: Text(maintenance.equipmentSerial ?? '시리얼 번호 없음'),
                subtitle: Text(
                  '${MaintenanceType.getDisplayName(maintenance.maintenanceType)} - '
                  '${DateFormat('yyyy-MM-dd').format(maintenance.endedAt)} 만료',
                ),
                trailing: maintenance.daysRemaining != null
                    ? Text(
                        '${maintenance.daysRemaining}일 남음',
                        style: TextStyle(
                          color: maintenance.daysRemaining! <= 7
                              ? Colors.red
                              : Colors.orange,
                          fontWeight: FontWeight.bold,
                        ),
                      )
                    : null,
                onTap: () {
                  Navigator.pop(context);
                  _showMaintenanceDetail(maintenance);
                },
              );
            },
          ),
        ),
        actions: [
          TextButton(
            onPressed: () => Navigator.pop(context),
            child: const Text('닫기'),
          ),
        ],
      ),
    );
  }

  void _deleteMaintenance(MaintenanceDto maintenance) {
    showDialog(
      context: context,
      builder: (context) => AlertDialog(
        title: const Text('유지보수 삭제'),
        content: Text(
          '${maintenance.equipmentSerial ?? "선택된"} 장비의 유지보수를 삭제하시겠습니까?\n'
          '삭제된 데이터는 복구할 수 있습니다.',
        ),
        actions: [
          TextButton(
            onPressed: () => Navigator.pop(context),
            child: const Text('취소'),
          ),
          TextButton(
            onPressed: () async {
              Navigator.pop(context);
              final success = await _controller.deleteMaintenance(maintenance.id!);
              if (success && mounted) {
                ScaffoldMessenger.of(context).showSnackBar(
                  const SnackBar(content: Text('유지보수가 삭제되었습니다')),
                );
              }
            },
            child: const Text('삭제', style: TextStyle(color: Colors.red)),
          ),
        ],
      ),
    );
  }

  void _showDeleteConfirmation() {
    showDialog(
      context: context,
      builder: (context) => AlertDialog(
        title: const Text('선택된 유지보수 삭제'),
        content: Text('선택된 ${_selectedItems.length}개의 유지보수를 삭제하시겠습니까?'),
        actions: [
          TextButton(
            onPressed: () => Navigator.pop(context),
            child: const Text('취소'),
          ),
          TextButton(
            onPressed: () async {
              Navigator.pop(context);
              // TODO: 일괄 삭제 구현
              setState(() {
                _selectedItems.clear();
              });
            },
            child: const Text('삭제', style: TextStyle(color: Colors.red)),
          ),
        ],
      ),
    );
  }
}