重构项目结构，移除Assignment相关功能，优化Submission模块

TechHelper.Server/Services/Subject/SubjectService.cs

@@ -0,0 +1,170 @@
+using AutoMapper;
+using Entities.Contracts;
+using Entities.DTO;
+using Microsoft.EntityFrameworkCore;
+using SharedDATA.Api;
+using TechHelper.Services.Beta;
+
+namespace TechHelper.Services.Beta
+{
+    public class SubjectService : ISubjectService
+    {
+        private readonly IUnitOfWork _work;
+        private readonly IMapper _mapper;
+
+        public SubjectService(IUnitOfWork work, IMapper mapper)
+        {
+            _work = work;
+            _mapper = mapper;
+        }
+
+        public async Task<ApiResponse> GetAllAsync(QueryParameter query)
+        {
+            try
+            {
+                var repository = _work.GetRepository<Subject>();
+
+                if (query.Search != null && !string.IsNullOrWhiteSpace(query.Search))
+                {
+                    var subjects = await repository.GetPagedListAsync(
+                        predicate: s => s.Name.Contains(query.Search),
+                        pageSize: query.PageSize,
+                        pageIndex: query.PageIndex
+                    );
+                    var subjectDtosFiltered = _mapper.Map<IEnumerable<TypeCommonDto>>(subjects.Items);
+                    return new ApiResponse(true, subjectDtosFiltered);
+                }
+                else
+                {
+                    var subjects = await repository.GetPagedListAsync(
+                        pageSize: query.PageSize,
+                        pageIndex: query.PageIndex
+                    );
+                    var subjectDtos = _mapper.Map<IEnumerable<TypeCommonDto>>(subjects.Items);
+                    return new ApiResponse(true, subjectDtos);
+                }
+            }
+            catch (Exception ex)
+            {
+                return new ApiResponse($"获取所有科目时发生错误: {ex.Message}");
+            }
+        }
+
+        public async Task<ApiResponse> GetAsync(Guid id)
+        {
+            try
+            {
+                var subject = await _work.GetRepository<Subject>().GetFirstOrDefaultAsync(
+                    predicate: s => s.Id == id,
+                    include: i => i
+                        .Include(s => s.QuestionTypes)
+                        .Include(s => s.Questions)
+                        .Include(s => s.SubjectTeachers));
+
+                if (subject == null)
+                {
+                    return new ApiResponse("科目未找到。");
+                }
+
+                var subjectDto = _mapper.Map<SubjectResponseDto>(subject);
+                return new ApiResponse(true, subjectDto);
+            }
+            catch (Exception ex)
+            {
+                return new ApiResponse($"获取科目时发生错误: {ex.Message}");
+            }
+        }
+
+        public async Task<ApiResponse> AddAsync(SubjectDto model)
+        {
+            try
+            {
+                // 检查是否已存在同名科目
+                var existingSubject = await _work.GetRepository<Subject>().GetFirstOrDefaultAsync(
+                    predicate: s => s.Name == model.Name);
+
+                if (existingSubject != null)
+                {
+                    return new ApiResponse($"科目 '{model.Name}' 已存在。");
+                }
+
+                var subject = _mapper.Map<Subject>(model);
+
+                await _work.GetRepository<Subject>().InsertAsync(subject);
+
+                if (await _work.SaveChangesAsync() > 0)
+                {
+                    return new ApiResponse(true, subject.Id);
+                }
+                return new ApiResponse("添加科目失败。");
+            }
+            catch (Exception ex)
+            {
+                return new ApiResponse($"添加科目时发生错误: {ex.Message}");
+            }
+        }
+
+        public async Task<ApiResponse> UpdateAsync(SubjectDto model)
+        {
+            try
+            {
+                var existingSubject = await _work.GetRepository<Subject>().GetFirstOrDefaultAsync(
+                    predicate: s => s.Id == model.Id);
+
+                if (existingSubject == null)
+                {
+                    return new ApiResponse("科目未找到。");
+                }
+
+                // 检查是否要修改为已存在的科目名称（排除当前科目）
+                var subjectWithSameName = await _work.GetRepository<Subject>().GetFirstOrDefaultAsync(
+                    predicate: s => s.Name == model.Name && s.Id != model.Id);
+
+                if (subjectWithSameName != null)
+                {
+                    return new ApiResponse($"科目名称 '{model.Name}' 已被其他科目使用。");
+                }
+
+                _mapper.Map(model, existingSubject);
+                _work.GetRepository<Subject>().Update(existingSubject);
+
+                if (await _work.SaveChangesAsync() > 0)
+                {
+                    var subjectDto = _mapper.Map<SubjectResponseDto>(existingSubject);
+                    return new ApiResponse(true, subjectDto);
+                }
+                return new ApiResponse("更新科目失败。");
+            }
+            catch (Exception ex)
+            {
+                return new ApiResponse($"更新科目时发生错误: {ex.Message}");
+            }
+        }
+
+        public async Task<ApiResponse> DeleteAsync(Guid id)
+        {
+            try
+            {
+                var existingSubject = await _work.GetRepository<Subject>().GetFirstOrDefaultAsync(
+                    predicate: s => s.Id == id);
+
+                if (existingSubject == null)
+                {
+                    return new ApiResponse("科目未找到。");
+                }
+
+                _work.GetRepository<Subject>().Delete(existingSubject);
+
+                if (await _work.SaveChangesAsync() > 0)
+                {
+                    return new ApiResponse(true, "科目删除成功。");
+                }
+                return new ApiResponse("删除科目失败。");
+            }
+            catch (Exception ex)
+            {
+                return new ApiResponse($"删除科目时发生错误: {ex.Message}");
+            }
+        }
+    }
+}