import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:provider/provider.dart';
import 'package:superport/screens/common/theme_shadcn.dart';
import 'package:superport/screens/common/custom_widgets/form_field_wrapper.dart';
import 'package:superport/screens/company/controllers/branch_controller.dart';
import 'package:superport/utils/validators.dart';
import 'package:superport/utils/phone_utils.dart';

/// 지점 관리 화면 (입력/수정 통합)
/// User/Warehouse Location 화면과 동일한 FormFieldWrapper 패턴 사용
class BranchFormScreen extends StatefulWidget {
  final int? branchId; // 수정 모드: 지점 ID, 생성 모드: null
  final String? parentCompanyName; // 수정 모드: 본사명 (표시용)
  
  const BranchFormScreen({
    super.key, 
    this.branchId, 
    this.parentCompanyName,
  });

  @override
  State<BranchFormScreen> createState() => _BranchFormScreenState();
}

class _BranchFormScreenState extends State<BranchFormScreen> {
  late BranchController _controller;

  @override
  void initState() {
    super.initState();
    _controller = BranchController(
      branchId: widget.branchId,
      parentCompanyName: widget.parentCompanyName,
    );
  }

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

  /// 지점 저장
  Future<void> _saveBranch() async {
    if (!_controller.formKey.currentState!.validate()) {
      return;
    }
    
    // 로딩 표시
    showDialog(
      context: context,
      barrierDismissible: false,
      builder: (context) => const Center(child: CircularProgressIndicator()),
    );
    
    try {
      final success = await _controller.saveBranch();
      
      if (mounted) {
        Navigator.pop(context); // 로딩 다이얼로그 닫기
        
        if (success) {
          ScaffoldMessenger.of(context).showSnackBar(
            SnackBar(
              content: Text(_controller.isEditMode ? '지점이 수정되었습니다.' : '지점이 등록되었습니다.'),
              backgroundColor: Colors.green,
            ),
          );
          Navigator.pop(context, true); // 성공 시 이전 화면으로
        } else {
          ScaffoldMessenger.of(context).showSnackBar(
            SnackBar(
              content: Text(_controller.errorMessage ?? '지점 저장에 실패했습니다.'),
              backgroundColor: Colors.red,
            ),
          );
        }
      }
    } catch (e) {
      if (mounted) {
        Navigator.pop(context); // 로딩 다이얼로그 닫기
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(
            content: Text('오류가 발생했습니다: $e'),
            backgroundColor: Colors.red,
          ),
        );
      }
    }
  }

  @override
  Widget build(BuildContext context) {
    return ChangeNotifierProvider.value(
      value: _controller,
      child: Scaffold(
        appBar: AppBar(
          title: Text(_controller.isEditMode 
              ? '${_controller.parentCompanyName} 지점 수정'
              : '지점 추가'),
          backgroundColor: ShadcnTheme.background,
          foregroundColor: ShadcnTheme.foreground,
        ),
        body: Consumer<BranchController>(
          builder: (context, controller, child) {
            // 로딩 상태 처리
            if (controller.isLoadingHeadquarters || 
                (controller.isEditMode && controller.isLoading && controller.originalBranch == null)) {
              return Center(
                child: Column(
                  mainAxisAlignment: MainAxisAlignment.center,
                  children: [
                    const CircularProgressIndicator(),
                    const SizedBox(height: 16),
                    Text(controller.isEditMode && controller.isLoading 
                        ? '지점 정보를 불러오는 중...' 
                        : '본사 목록을 불러오는 중...'),
                  ],
                ),
              );
            }

            if (controller.headquartersList.isEmpty) {
              return Center(
                child: Column(
                  mainAxisAlignment: MainAxisAlignment.center,
                  children: [
                    const Icon(Icons.domain_disabled, size: 64, color: Colors.grey),
                    const SizedBox(height: 16),
                    const Text('등록된 본사가 없습니다'),
                    const SizedBox(height: 8),
                    const Text('먼저 본사를 등록해주세요'),
                    const SizedBox(height: 16),
                    ElevatedButton(
                      onPressed: () => controller.refreshHeadquarters(),
                      child: const Text('새로고침'),
                    ),
                  ],
                ),
              );
            }

            return Padding(
              padding: const EdgeInsets.all(16.0),
              child: Form(
                key: controller.formKey,
                child: SingleChildScrollView(
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.stretch,
                    children: [
                      // 본사 선택 (필수 - 수정 모드에서는 읽기 전용)
                      FormFieldWrapper(
                        label: "본사 선택",
                        isRequired: true,
                        child: controller.isEditMode
                            ? TextFormField(
                                initialValue: controller.parentCompanyName ?? '본사명 로딩 중...',
                                decoration: const InputDecoration(
                                  border: OutlineInputBorder(),
                                  enabled: false, // 수정 모드에서는 비활성화
                                ),
                                style: const TextStyle(color: Colors.grey),
                              )
                            : DropdownButtonFormField<int>(
                                value: controller.selectedHeadquarterId,
                                decoration: const InputDecoration(
                                  hintText: '본사를 선택하세요',
                                  border: OutlineInputBorder(),
                                ),
                                items: controller.headquartersList.map((company) {
                                  return DropdownMenuItem<int>(
                                    value: company.id,
                                    child: Text(
                                      company.name,
                                      overflow: TextOverflow.ellipsis,
                                    ),
                                  );
                                }).toList(),
                                onChanged: (value) {
                                  if (value != null) {
                                    final selectedCompany = controller.headquartersList
                                        .firstWhere((company) => company.id == value);
                                    controller.selectHeadquarters(value, selectedCompany.name);
                                  }
                                },
                                validator: (value) {
                                  if (value == null) {
                                    return '본사를 선택하세요';
                                  }
                                  return null;
                                },
                              ),
                      ),

                      // 지점명 (필수)
                      FormFieldWrapper(
                        label: "지점명",
                        isRequired: true,
                        child: TextFormField(
                          controller: controller.nameController,
                          decoration: const InputDecoration(
                            hintText: '지점명을 입력하세요',
                            border: OutlineInputBorder(),
                          ),
                          validator: (value) {
                            if (value == null || value.trim().isEmpty) {
                              return '지점명을 입력하세요';
                            }
                            if (value.trim().length < 2) {
                              return '지점명은 2자 이상 입력하세요';
                            }
                            return null;
                          },
                          textInputAction: TextInputAction.next,
                        ),
                      ),

                      // 주소 (선택)
                      FormFieldWrapper(
                        label: "주소",
                        child: TextFormField(
                          controller: controller.addressController,
                          decoration: const InputDecoration(
                            hintText: '지점 주소를 입력하세요',
                            border: OutlineInputBorder(),
                          ),
                          maxLines: 2,
                          textInputAction: TextInputAction.next,
                        ),
                      ),

                      // 담당자명 (필수)
                      FormFieldWrapper(
                        label: "담당자명",
                        isRequired: true,
                        child: TextFormField(
                          controller: controller.contactNameController,
                          decoration: const InputDecoration(
                            hintText: '담당자명을 입력하세요',
                            border: OutlineInputBorder(),
                          ),
                          validator: (value) {
                            if (value == null || value.trim().isEmpty) {
                              return '담당자명을 입력하세요';
                            }
                            return null;
                          },
                          textInputAction: TextInputAction.next,
                        ),
                      ),

                      // 담당자 직급 (선택)
                      FormFieldWrapper(
                        label: "담당자 직급",
                        child: TextFormField(
                          controller: controller.contactPositionController,
                          decoration: const InputDecoration(
                            hintText: '담당자 직급을 입력하세요',
                            border: OutlineInputBorder(),
                          ),
                          textInputAction: TextInputAction.next,
                        ),
                      ),

                      // 담당자 연락처 (필수) - Company 폼과 동일한 패턴
                      FormFieldWrapper(
                        label: "담당자 연락처",
                        isRequired: true,
                        child: Row(
                          children: [
                            // 접두사 드롭다운 (010, 02, 031 등)
                            Container(
                              padding: const EdgeInsets.symmetric(horizontal: 12),
                              decoration: BoxDecoration(
                                border: Border.all(color: Colors.grey),
                                borderRadius: BorderRadius.circular(4),
                              ),
                              child: DropdownButton<String>(
                                value: controller.selectedPhonePrefix,
                                items: controller.phonePrefixes.map((prefix) {
                                  return DropdownMenuItem(
                                    value: prefix,
                                    child: Text(prefix),
                                  );
                                }).toList(),
                                onChanged: (value) {
                                  if (value != null) {
                                    controller.selectPhonePrefix(value);
                                  }
                                },
                                underline: Container(), // 밑줄 제거
                              ),
                            ),
                            const SizedBox(width: 8),
                            const Text('-', style: TextStyle(fontSize: 16)),
                            const SizedBox(width: 8),
                            // 전화번호 입력 (7-8자리)
                            Expanded(
                              child: TextFormField(
                                controller: controller.phoneNumberController,
                                decoration: const InputDecoration(
                                  hintText: '1234-5678',
                                  border: OutlineInputBorder(),
                                ),
                                keyboardType: TextInputType.phone,
                                inputFormatters: [
                                  FilteringTextInputFormatter.digitsOnly,
                                  TextInputFormatter.withFunction((oldValue, newValue) {
                                    final formatted = PhoneUtils.formatPhoneNumberByPrefix(
                                      controller.selectedPhonePrefix,
                                      newValue.text,
                                    );
                                    return TextEditingValue(
                                      text: formatted,
                                      selection: TextSelection.collapsed(offset: formatted.length),
                                    );
                                  }),
                                ],
                                validator: (value) {
                                  if (value == null || value.trim().isEmpty) {
                                    return '전화번호를 입력하세요';
                                  }
                                  final digitsOnly = value.replaceAll(RegExp(r'[^\d]'), '');
                                  if (digitsOnly.length < 7) {
                                    return '전화번호는 7-8자리 숫자를 입력해주세요';
                                  }
                                  return null;
                                },
                                textInputAction: TextInputAction.next,
                              ),
                            ),
                          ],
                        ),
                      ),

                      // 담당자 이메일 (필수)
                      FormFieldWrapper(
                        label: "담당자 이메일",
                        isRequired: true,
                        child: TextFormField(
                          controller: controller.contactEmailController,
                          decoration: const InputDecoration(
                            hintText: 'example@company.com',
                            border: OutlineInputBorder(),
                          ),
                          keyboardType: TextInputType.emailAddress,
                          validator: (value) {
                            if (value == null || value.trim().isEmpty) {
                              return '담당자 이메일을 입력하세요';
                            }
                            return validateEmail(value);
                          },
                          textInputAction: TextInputAction.next,
                        ),
                      ),

                      // 비고 (선택)
                      FormFieldWrapper(
                        label: "비고",
                        child: TextFormField(
                          controller: controller.remarkController,
                          decoration: const InputDecoration(
                            hintText: '추가 정보나 메모를 입력하세요',
                            border: OutlineInputBorder(),
                          ),
                          maxLines: 3,
                          textInputAction: TextInputAction.done,
                        ),
                      ),

                      const SizedBox(height: 32),

                      // 저장 버튼
                      ElevatedButton(
                        onPressed: controller.isSaving ? null : _saveBranch,
                        style: ElevatedButton.styleFrom(
                          backgroundColor: ShadcnTheme.primary,
                          foregroundColor: Colors.white,
                          minimumSize: const Size.fromHeight(48),
                          shape: RoundedRectangleBorder(
                            borderRadius: BorderRadius.circular(8),
                          ),
                        ),
                        child: controller.isSaving
                            ? const SizedBox(
                                height: 20,
                                width: 20,
                                child: CircularProgressIndicator(
                                  valueColor: AlwaysStoppedAnimation<Color>(Colors.white),
                                  strokeWidth: 2,
                                ),
                              )
                            : Text(
                                controller.isEditMode ? '지점 수정' : '지점 등록',
                                style: const TextStyle(
                                  fontSize: 16,
                                  fontWeight: FontWeight.bold,
                                ),
                              ),
                      ),

                      const SizedBox(height: 16),
                    ],
                  ),
                ),
              ),
            );
          },
        ),
      ),
    );
  }
}