import 'package:flutter/material.dart';
import 'package:superport/screens/common/theme_shadcn.dart';
import 'package:shadcn_ui/shadcn_ui.dart';
import 'package:get_it/get_it.dart';

import '../../data/models/rent_dto.dart';
import '../equipment/controllers/equipment_history_controller.dart';

class RentFormDialog extends StatefulWidget {
  final RentDto? rent;
  final Future<bool> Function(RentRequestDto) onSubmit;

  const RentFormDialog({
    super.key,
    this.rent,
    required this.onSubmit,
  });

  @override
  State<RentFormDialog> createState() => _RentFormDialogState();
}

class _RentFormDialogState extends State<RentFormDialog> {
  final _formKey = GlobalKey<FormState>();
  late final EquipmentHistoryController _historyController;
  
  // 백엔드 스키마에 맞는 필드만 유지
  int? _selectedEquipmentHistoryId;
  DateTime _startDate = DateTime.now();
  DateTime? _endDate;
  
  bool _isLoading = false;
  bool _isLoadingHistories = false;
  String? _historiesError;

  @override
  void initState() {
    super.initState();
    _historyController = GetIt.instance<EquipmentHistoryController>();
    
    if (widget.rent != null) {
      _initializeForm(widget.rent!);
    }
    
    _loadEquipmentHistories();
  }
  
  Future<void> _loadEquipmentHistories() async {
    setState(() {
      _isLoadingHistories = true;
      _historiesError = null; // 오류 상태 초기화
    });
    
    try {
      await _historyController.loadHistory();
      setState(() => _historiesError = null); // 성공 시 오류 상태 클리어
    } catch (e) {
      debugPrint('장비 이력 로딩 실패: $e');
      setState(() => _historiesError = '장비 이력을 불러오는 중 오류가 발생했습니다: ${e.toString()}');
    } finally {
      if (mounted) {
        setState(() => _isLoadingHistories = false);
      }
    }
  }
  
  // 재시도 기능 추가 (UserForm 패턴과 동일)
  void _retryLoadHistories() {
    _loadEquipmentHistories();
  }

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

  void _initializeForm(RentDto rent) {
    _selectedEquipmentHistoryId = rent.equipmentHistoryId;
    _startDate = rent.startedAt;
    _endDate = rent.endedAt;
  }

  Future<void> _selectStartDate() async {
    final date = await showDatePicker(
      context: context,
      initialDate: _startDate,
      firstDate: DateTime(2020),
      lastDate: DateTime(2030),
    );

    if (date != null) {
      setState(() {
        _startDate = date;
      });
    }
  }
  
  Future<void> _selectEndDate() async {
    final date = await showDatePicker(
      context: context,
      initialDate: _endDate ?? DateTime.now().add(const Duration(days: 30)),
      firstDate: _startDate,
      lastDate: DateTime(2030),
    );

    if (date != null) {
      setState(() {
        _endDate = date;
      });
    }
  }

  Future<void> _submit() async {
    if (_selectedEquipmentHistoryId == null || _endDate == null) {
      ScaffoldMessenger.of(context).showSnackBar(
        const SnackBar(content: Text('장비 이력과 종료일을 선택해주세요')),
      );
      return;
    }

    setState(() => _isLoading = true);

    try {
      final request = RentRequestDto(
        equipmentHistoryId: _selectedEquipmentHistoryId!,
        startedAt: _startDate,
        endedAt: _endDate!,
      );

      await widget.onSubmit(request);
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(content: Text('오류가 발생했습니다: $e')),
        );
      }
    } finally {
      if (mounted) {
        setState(() => _isLoading = false);
      }
    }
  }

  @override
  Widget build(BuildContext context) {
    return Dialog(
      child: Container(
        width: 500,
        constraints: const BoxConstraints(maxHeight: 600),
        padding: const EdgeInsets.all(24),
        child: Column(
          mainAxisSize: MainAxisSize.min,
          children: [
            // 제목
            Text(
              widget.rent != null ? '임대 계약 수정' : '새 임대 계약',
              style: Theme.of(context).textTheme.headlineSmall,
            ),
            const SizedBox(height: 24),

            // 폼 (백엔드 스키마 3개 필드만 포함)
            Expanded(
              child: Form(
                key: _formKey,
                child: SingleChildScrollView(
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      // 장비 이력 선택 (백엔드 필수 필드)
                      Text('장비 선택 *', style: Theme.of(context).textTheme.titleMedium),
                      const SizedBox(height: 8),
                      
                      // 3단계 상태 처리 (UserForm 패턴 적용)
                      _isLoadingHistories
                          ? SizedBox(
                              height: 56,
                              child: Center(
                                child: Row(
                                  mainAxisAlignment: MainAxisAlignment.center,
                                  children: const [
                                    SizedBox(width: 120, child: ShadProgress()),
                                    SizedBox(width: 8),
                                    Text('장비 이력을 불러오는 중...'),
                                  ],
                                ),
                              ),
                            )
                          // 오류 발생 시 오류 컨테이너 표시
                          : _historiesError != null
                              ? Container(
                                  padding: const EdgeInsets.all(16),
                                  decoration: BoxDecoration(
                                    color: Colors.red.shade50,
                                    border: Border.all(color: Colors.red.shade200),
                                    borderRadius: BorderRadius.circular(8),
                                  ),
                                  child: Column(
                                    crossAxisAlignment: CrossAxisAlignment.start,
                                    children: [
                                      Row(
                                        children: [
                                          Icon(Icons.error, color: Colors.red.shade600, size: 20),
                                          const SizedBox(width: 8),
                                          const Text('장비 이력 로딩 실패', style: TextStyle(fontWeight: FontWeight.w500)),
                                        ],
                                      ),
                                      const SizedBox(height: 8),
                                      Text(
                                        _historiesError!,
                                        style: TextStyle(color: Colors.red.shade700, fontSize: 14),
                                      ),
                                      const SizedBox(height: 12),
                                      ShadButton(
                                        onPressed: _retryLoadHistories,
                                        child: const Row(
                                          mainAxisSize: MainAxisSize.min,
                                          children: [
                                            Icon(Icons.refresh, size: 16),
                                            SizedBox(width: 4),
                                            Text('다시 시도'),
                                          ],
                                        ),
                                      ),
                                    ],
                                  ),
                                )
                              // 정상 상태: 드롭다운 표시
                              : ShadSelect<int>(
                              placeholder: const Text('장비를 선택하세요'),
                              options: _historyController.historyList.map((history) {
                                return ShadOption(
                                  value: history.id!,
                                  child: Column(
                                    crossAxisAlignment: CrossAxisAlignment.start,
                                    mainAxisSize: MainAxisSize.min,
                                    children: [
                                      Text(
                                        '${history.equipment?.serialNumber ?? "Serial N/A"} - ${history.equipment?.modelName ?? "Model N/A"}',
                                        style: const TextStyle(fontWeight: FontWeight.w500),
                                        overflow: TextOverflow.ellipsis,
                                      ),
                                      Text(
                                        '거래: ${history.transactionType} | 수량: ${history.quantity} | ${history.transactedAt.toString().split(' ')[0]}',
                                        style: const TextStyle(fontSize: 12, color: Colors.grey),
                                        overflow: TextOverflow.ellipsis,
                                      ),
                                    ],
                                  ),
                                );
                              }).toList(),
                              selectedOptionBuilder: (context, value) {
                                if (_historyController.historyList.isEmpty) {
                                  return const Text('이력 없음');
                                }
                                final selectedHistory = _historyController.historyList
                                    .firstWhere(
                                      (h) => h.id == value,
                                      orElse: () => _historyController.historyList.first,
                                    );
                                return Text(
                                  '${selectedHistory.equipment?.serialNumber ?? "Serial N/A"} - ${selectedHistory.equipment?.modelName ?? "Model N/A"}',
                                  overflow: TextOverflow.ellipsis,
                                );
                              },
                              onChanged: (value) {
                                setState(() {
                                  _selectedEquipmentHistoryId = value;
                                });
                              },
                              initialValue: _selectedEquipmentHistoryId,
                            ),
                      const SizedBox(height: 20),

                      // 임대 기간 (백엔드 필수 필드)
                      Text('임대 기간', style: Theme.of(context).textTheme.titleMedium),
                      const SizedBox(height: 12),

                      Row(
                        children: [
                          Expanded(
                            child: InkWell(
                              onTap: _selectStartDate,
                              child: Container(
                                padding: const EdgeInsets.all(16),
                                decoration: BoxDecoration(
                                  border: Border.all(color: Colors.grey),
                                  borderRadius: BorderRadius.circular(4),
                                ),
                                child: Row(
                                  children: [
                                    const Icon(Icons.calendar_today),
                                    const SizedBox(width: 8),
                                    Column(
                                      crossAxisAlignment: CrossAxisAlignment.start,
                                      children: [
                                        const Text('시작일 *', style: TextStyle(fontSize: 12, color: Colors.grey)),
                                        Text(
                                          '${_startDate.year}-${_startDate.month.toString().padLeft(2, '0')}-${_startDate.day.toString().padLeft(2, '0')}',
                                          style: const TextStyle(fontSize: 16),
                                        ),
                                      ],
                                    ),
                                  ],
                                ),
                              ),
                            ),
                          ),
                          const SizedBox(width: 16),
                          Expanded(
                            child: InkWell(
                              onTap: _selectEndDate,
                              child: Container(
                                padding: const EdgeInsets.all(16),
                                decoration: BoxDecoration(
                                  border: Border.all(color: Colors.grey),
                                  borderRadius: BorderRadius.circular(4),
                                ),
                                child: Row(
                                  children: [
                                    const Icon(Icons.calendar_today),
                                    const SizedBox(width: 8),
                                    Column(
                                      crossAxisAlignment: CrossAxisAlignment.start,
                                      children: [
                                        const Text('종료일 *', style: TextStyle(fontSize: 12, color: Colors.grey)),
                                        Text(
                                          _endDate != null 
                                              ? '${_endDate!.year}-${_endDate!.month.toString().padLeft(2, '0')}-${_endDate!.day.toString().padLeft(2, '0')}'
                                              : '날짜 선택',
                                          style: TextStyle(
                                            fontSize: 16,
                color: _endDate != null ? ShadcnTheme.foreground : ShadcnTheme.mutedForeground,
                                          ),
                                        ),
                                      ],
                                    ),
                                  ],
                                ),
                              ),
                            ),
                          ),
                        ],
                      ),
                      const SizedBox(height: 16),

                      // 임대 기간 표시
                      if (_endDate != null)
                        Container(
                          padding: const EdgeInsets.all(12),
                          decoration: BoxDecoration(
                            color: Colors.blue.shade50,
                            borderRadius: BorderRadius.circular(8),
                            border: Border.all(color: Colors.blue.shade200),
                          ),
                          child: Row(
                            mainAxisAlignment: MainAxisAlignment.center,
                            children: [
                              const Icon(Icons.info, color: Colors.blue),
                              const SizedBox(width: 8),
                              Text(
                                '임대 기간: ${_endDate!.difference(_startDate).inDays + 1}일',
                                style: const TextStyle(fontWeight: FontWeight.bold),
                              ),
                            ],
                          ),
                        ),
                    ],
                  ),
                ),
              ),
            ),

            const SizedBox(height: 24),

            // 버튼
            Row(
              mainAxisAlignment: MainAxisAlignment.end,
              children: [
                TextButton(
                  onPressed: _isLoading ? null : () => Navigator.of(context).pop(),
                  child: const Text('취소'),
                ),
                const SizedBox(width: 8),
                ElevatedButton(
                  onPressed: _isLoading ? null : _submit,
                  child: _isLoading
                      ? const SizedBox(
                          width: 20,
                          height: 20,
                          child: CircularProgressIndicator(strokeWidth: 2),
                        )
                      : Text(widget.rent != null ? '수정' : '생성'),
                ),
              ],
            ),
          ],
        ),
      ),
    );
  }
}