using Infrastructure.Attribute;
using Infrastructure.Extensions;
using ZR.LiveForum.Model.Liveforum.Dto;
using ZR.LiveForum.Model.Liveforum;
using ZR.Repository;
using ZR.Service.Liveforum.ILiveforumService;

namespace ZR.Service.Liveforum
{
    /// <summary>
    /// 论坛帖子Service业务层处理
    /// </summary>
    [AppService(ServiceType = typeof(IT_PostsService), ServiceLifetime = LifeTime.Transient)]
    public class T_PostsService : BaseService<T_Posts>, IT_PostsService
    {
        /// <summary>
        /// 查询论坛帖子列表
        /// </summary>
        /// <param name="parm"></param>
        /// <returns></returns>
        public PagedInfo<T_PostsDto> GetList(T_PostsQueryDto parm)
        {
            var predicate = QueryExp(parm);

            var query = Queryable()
                .Where(predicate.ToExpression())
                .LeftJoin<T_Users>((p, u) => p.UserId == u.Id);

            // 在 Select 之前进行排序，使用表别名
            if (parm.Sort.IsNotEmpty())
            {
                var orderType = parm.SortType.Contains("desc") ? OrderByType.Desc : OrderByType.Asc;
                query = ApplyOrderBy(query, parm.Sort, orderType);
            }
            else
            {
                // 默认排序
                query = query.OrderBy((p, u) => p.Id, OrderByType.Desc);
            }

            var response = query.Select((p, u) => new T_PostsDto()
            {
                Id = p.Id,
                UserId = p.UserId,
                NickName = u.NickName,
                Title = p.Title,
                CoverImage = p.CoverImage,
                Content = p.Content,
                CategoryId = p.CategoryId,
                ViewCount = p.ViewCount,
                LikeCount = p.LikeCount,
                CommentCount = p.CommentCount,
                ShareCount = p.ShareCount,
                IsTop = p.IsTop,
                IsHot = p.IsHot,
                IsEssence = p.IsEssence,
                Status = p.Status,
                PublishTime = p.PublishTime,
                IsDeleted = p.IsDeleted,
                DeletedAt = p.DeletedAt,
                CreatedAt = p.CreatedAt,
                UpdatedAt = p.UpdatedAt,
            }, true);

            var resp = ToPage(response, parm);

            // 批量查询并填充图片列表
            if (resp.Result != null && resp.Result.Any())
            {
                var postIds = resp.Result.Select(x => x.Id).ToList();
                var images = Context.Queryable<T_PostImages>()
                    .Where(x => postIds.Contains(x.PostId))
                    .OrderBy(x => x.SortOrder)
                    .ToList();

                var imagesDict = images
                    .GroupBy(x => x.PostId)
                    .ToDictionary(
                        g => g.Key,
                        g => g.Select(x => new PostImageDto
                        {
                            Id = x.Id,
                            ImageUrl = x.ImageUrl,
                            SortOrder = x.SortOrder
                        }).ToList()
                    );

                Context.ThenMapper(resp.Result, item =>
                {
                    item.Images = imagesDict.GetValueOrDefault(item.Id, new List<PostImageDto>());
                });
            }

            return resp;
        }

        /// <summary>
        /// 应用排序（在 Join 查询中使用表别名）
        /// </summary>
        private ISugarQueryable<T_Posts, T_Users> ApplyOrderBy(ISugarQueryable<T_Posts, T_Users> query, string sortField, OrderByType orderType)
        {
            // 将 DTO 属性名映射到表字段表达式
            return sortField.ToLower() switch
            {
                "id" => query.OrderBy((p, u) => p.Id, orderType),
                "userid" => query.OrderBy((p, u) => p.UserId, orderType),
                "nickname" => query.OrderBy((p, u) => u.NickName, orderType),
                "title" => query.OrderBy((p, u) => p.Title, orderType),
                "coverimage" => query.OrderBy((p, u) => p.CoverImage, orderType),
                "content" => query.OrderBy((p, u) => p.Content, orderType),
                "categoryid" => query.OrderBy((p, u) => p.CategoryId, orderType),
                "viewcount" => query.OrderBy((p, u) => p.ViewCount, orderType),
                "likecount" => query.OrderBy((p, u) => p.LikeCount, orderType),
                "commentcount" => query.OrderBy((p, u) => p.CommentCount, orderType),
                "sharecount" => query.OrderBy((p, u) => p.ShareCount, orderType),
                "istop" => query.OrderBy((p, u) => p.IsTop, orderType),
                "ishot" => query.OrderBy((p, u) => p.IsHot, orderType),
                "isessence" => query.OrderBy((p, u) => p.IsEssence, orderType),
                "status" => query.OrderBy((p, u) => p.Status, orderType),
                "publishtime" => query.OrderBy((p, u) => p.PublishTime, orderType),
                "isdeleted" => query.OrderBy((p, u) => p.IsDeleted, orderType),
                "deletedat" => query.OrderBy((p, u) => p.DeletedAt, orderType),
                "createdat" => query.OrderBy((p, u) => p.CreatedAt, orderType),
                "updatedat" => query.OrderBy((p, u) => p.UpdatedAt, orderType),
                _ => query.OrderBy((p, u) => p.Id, OrderByType.Desc) // 默认排序
            };
        }

        /// <summary>
        /// 读取列表
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="source">查询表单式</param>
        /// <param name="parm">分页参数</param>
        /// <returns></returns>
        public PagedInfo<T> ToPage<T>(ISugarQueryable<T> source, PagerInfo parm)
        {
            var page = new PagedInfo<T>();
            var total = 0;
            page.PageSize = parm.PageSize;
            page.PageIndex = parm.PageNum;
            // 注意：排序已经在 Select 之前完成了，这里不再需要排序
            page.Result = source
                .ToPageList(parm.PageNum, parm.PageSize, ref total);
            page.TotalNum = total;
            return page;
        }



        /// <summary>
        /// 获取详情
        /// </summary>
        /// <param name="Id"></param>
        /// <returns></returns>
        public T_Posts GetInfo(long Id)
        {
            var response = Queryable()
                .Where(x => x.Id == Id)
                .First();

            return response;
        }

        /// <summary>
        /// 添加论坛帖子
        /// </summary>
        /// <param name="model"></param>
        /// <returns></returns>
        public T_Posts AddT_Posts(T_Posts model)
        {
            return Insertable(model).ExecuteReturnEntity();
        }

        /// <summary>
        /// 修改论坛帖子
        /// </summary>
        /// <param name="model"></param>
        /// <returns></returns>
        public int UpdateT_Posts(T_Posts model)
        {
            return Update(model, true, "修改论坛帖子");
        }

        /// <summary>
        /// 导出论坛帖子
        /// </summary>
        /// <param name="parm"></param>
        /// <returns></returns>
        public PagedInfo<T_PostsDto> ExportList(T_PostsQueryDto parm)
        {
            parm.PageNum = 1;
            parm.PageSize = 100000;
            var predicate = QueryExp(parm);

            var query = Queryable()
                .Where(predicate.ToExpression())
                .LeftJoin<T_Users>((p, u) => p.UserId == u.Id);

            // 导出时使用默认排序
            query = query.OrderBy((p, u) => p.Id, OrderByType.Desc);

            var response = query.Select((p, u) => new T_PostsDto()
            {
                Id = p.Id,
                UserId = p.UserId,
                NickName = u.NickName,
                Title = p.Title,
                CoverImage = p.CoverImage,
                Content = p.Content,
                CategoryId = p.CategoryId,
                ViewCount = p.ViewCount,
                LikeCount = p.LikeCount,
                CommentCount = p.CommentCount,
                ShareCount = p.ShareCount,
                IsTop = p.IsTop,
                IsHot = p.IsHot,
                IsEssence = p.IsEssence,
                Status = p.Status,
                PublishTime = p.PublishTime,
                IsDeleted = p.IsDeleted,
                DeletedAt = p.DeletedAt,
                CreatedAt = p.CreatedAt,
                UpdatedAt = p.UpdatedAt,
                //IsTopLabel = p.IsTop.GetConfigValue<Model.System.SysDictData>("liveforum_action_bool"),
                //StatusLabel = p.Status.GetConfigValue<Model.System.SysDictData>("liveforum_posts_status"),
            }, true);
            var resp = ToPage(response, parm);

            return resp;
        }

        /// <summary>
        /// 查询导出表达式
        /// </summary>
        /// <param name="parm"></param>
        /// <returns></returns>
        private static Expressionable<T_Posts> QueryExp(T_PostsQueryDto parm)
        {
            var predicate = Expressionable.Create<T_Posts>();

            predicate = predicate.AndIF(parm.UserId != null, it => it.UserId == parm.UserId);
            predicate = predicate.AndIF(!string.IsNullOrEmpty(parm.Title), it => it.Title == parm.Title || it.Content.Contains(parm.Title));
            predicate = predicate.AndIF(parm.Status != null, it => it.Status == parm.Status);
            predicate = predicate.AndIF(parm.IsDeleted != null, it => it.IsDeleted == parm.IsDeleted);
            return predicate;
        }
    }
}