using AutoMapper;
using AutoMapper.Internal.Mappers;
using Entities.Contracts;
using Entities.DTO;

namespace TechHelper.Context
{
	public class AutoMapperProFile : Profile
	{

		public static class EnumMappingHelpers
		{
			public static TEnum ParseEnumSafe<TEnum>(string sourceString, TEnum defaultValue) where TEnum : struct, Enum
			{
				if (Enum.TryParse(sourceString, true, out TEnum parsedValue))
				{
					return parsedValue;
				}
				return defaultValue;
			}
		}

		public AutoMapperProFile()
		{
			CreateMap<UserForRegistrationDto, User>()
				.ForMember(dest => dest.Id, opt => opt.Ignore())                                    // ID由IdentityUser生成
				.ForMember(dest => dest.UserName, opt => opt.MapFrom(src => src.Name))              // 或者 MapFrom(src => src.Name)
				.ForMember(dest => dest.Email, opt => opt.MapFrom(src => src.Email))
				.ForMember(dest => dest.PhoneNumber, opt => opt.MapFrom(src => src.PhoneNumber))
				.ForMember(dest => dest.Address, opt => opt.MapFrom(src => src.HomeAddress))        // 映射到 IdentityUser 的 Address 属性
				.ForMember(dest => dest.PasswordHash, opt => opt.Ignore())                          // 密码哈希由 UserManager 处理
				.ForMember(dest => dest.EmailConfirmed, opt => opt.Ignore());                       // 邮箱确认状态由服务层处理

			CreateMap<ClassDto, Class>()
				.ForMember(d => d.Number, o => o.MapFrom(src => src.Class)).ReverseMap();

			CreateMap<SubQuestionDto, Question>()
				 .ForMember(dest => dest.Id, opt => opt.Ignore())
				 .ForMember(dest => dest.QuestionText, opt => opt.MapFrom(src => src.Stem))
				 .ForMember(dest => dest.CorrectAnswer, opt => opt.MapFrom(src => src.SampleAnswer))
				 .ForMember(dest => dest.QuestionType, opt => opt.MapFrom(src => EnumMappingHelpers.ParseEnumSafe(src.QuestionType, QuestionType.Unknown)))
				 .ForMember(dest => dest.DifficultyLevel, opt => opt.MapFrom(src => EnumMappingHelpers.ParseEnumSafe(src.DifficultyLevel, DifficultyLevel.easy)))
				 .ForMember(dest => dest.SubjectArea, opt => opt.MapFrom(src => EnumMappingHelpers.ParseEnumSafe(src.DifficultyLevel, SubjectAreaEnum.Unknown)))
				 .ForMember(dest => dest.CreatedBy, opt => opt.Ignore())
				 .ForMember(dest => dest.CreatedAt, opt => opt.Ignore())
				 .ForMember(dest => dest.UpdatedAt, opt => opt.Ignore())
				 .ForMember(dest => dest.IsDeleted, opt => opt.Ignore());

			// 2. Question -> SubQuestionDto (查看时)
			CreateMap<Question, SubQuestionDto>()
				.ForMember(dest => dest.Stem, opt => opt.MapFrom(src => src.QuestionText))
				.ForMember(dest => dest.Score, opt => opt.Ignore()) // Question 实体没有 Score 字段，需要从 AssignmentQuestion 获取
				.ForMember(dest => dest.SampleAnswer, opt => opt.MapFrom(src => src.CorrectAnswer))
				.ForMember(dest => dest.QuestionType, opt => opt.MapFrom(src => src.QuestionType.ToString()))
				.ForMember(dest => dest.DifficultyLevel, opt => opt.MapFrom(src => src.DifficultyLevel.ToString()))
				.ForMember(dest => dest.Options, opt => opt.Ignore()); // Options 需要单独处理

			CreateMap<Assignment, ExamDto>()
				.ForMember(dest => dest.AssignmentTitle, opt => opt.MapFrom(src => src.Title))
				.ForMember(dest => dest.Description, opt => opt.MapFrom(src => src.Description))
				.ForMember(dest => dest.AssignmentId, opt => opt.MapFrom(src => src.Id))
				.ForMember(dest => dest.QuestionGroups, opt => opt.MapFrom(src =>
																	src.AssignmentGroups.FirstOrDefault(ag => ag.ParentGroup == null)))
				.ForMember(dest => dest.SubjectArea, opt => opt.MapFrom(src => src.SubjectArea.ToString()));

			CreateMap<AssignmentGroup, QuestionGroupDto>()
				.ForMember(dest => dest.SubQuestionGroups, opt => opt.MapFrom(src => src.ChildAssignmentGroups))
				.ForMember(dest => dest.SubQuestions, opt => opt.MapFrom(src => src.AssignmentQuestions));

			CreateMap<AssignmentQuestion, SubQuestionDto>()
				.ForMember(dest => dest.Stem, opt => opt.MapFrom(src => src.Question.QuestionText))
				.ForMember(dest => dest.SampleAnswer, opt => opt.MapFrom(src => src.Question.CorrectAnswer))
				.ForMember(dest => dest.QuestionType, opt => opt.MapFrom(src => src.Question.QuestionType.ToString()))
				.ForMember(dest => dest.DifficultyLevel, opt => opt.MapFrom(src => src.Question.DifficultyLevel.ToString()));



			CreateMap<QuestionGroupDto, AssignmentGroup>()
				.ForMember(dest => dest.ChildAssignmentGroups, opt => opt.MapFrom(src => src.SubQuestionGroups))
				.ForMember(dest => dest.AssignmentQuestions, opt => opt.MapFrom(src => src.SubQuestions));

			CreateMap<SubQuestionDto, AssignmentQuestion>()
				.ForMember(dest => dest.Question, opt => opt.MapFrom(src => src)); // 映射到嵌套的 Question 对象

			CreateMap<QuestionGroupDto, QuestionGroup>()
				.ForMember(dest => dest.ChildQuestionGroups, opt => opt.MapFrom(src => src.SubQuestionGroups))
				.ForMember(dest => dest.Title, opt => opt.MapFrom(src => src.Title))
				.ForMember(dest => dest.Description, opt => opt.MapFrom(src => src.Descript));



			CreateMap<Assignment, ExamDto>();
		}
	}

}