using FlexJobApi.Core;
using FlexJobApi.Core.Models;
using Furion.DatabaseAccessor;
using Mapster;
using MediatR;
using Microsoft.EntityFrameworkCore;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace FlexJobApi.User.Application
{
    /// <summary>
    /// 查询菜单列表
    /// </summary>
    public class GetMenusQueryHandler(
        IRepository<Menu> rep)
        : IRequestHandler<GetMenusQuery, List<GetMenusQueryResultItem>>
    {
        private readonly IRepository<Menu> rep = rep;

        /// <inheritdoc/>
        public async Task<List<GetMenusQueryResultItem>> Handle(GetMenusQuery request, CancellationToken cancellationToken)
        {
            var q = rep.AsQueryable().AsNoTracking()
                .Where(it => it.UserType == request.UserType && it.ClientType == request.ClientType)
                .Where(it => it.Type == EnumMenuType.Menu || it.Type == EnumMenuType.Page || it.Type == EnumMenuType.Modal);
            var all = await q.ProjectToType<GetMenusQueryResultItem>().ToListAsync();
            var models = all.Where(it => it.ParentId == null).ToList();
            var roleMenuIds =
                request.RoleId.HasValue
                ? rep.Change<RoleMenu>().Where(it => it.RoleId == request.RoleId).DistinctSelect(it => it.MenuId)
                : [];
            LoopChildrens(models, all, roleMenuIds);
            return models;
        }

        /// <summary>
        /// 递归赋值下级菜单
        /// </summary>
        /// <param name="models"></param>
        /// <param name="all"></param>
        /// <param name="roleMenuIds"></param>
        private void LoopChildrens(List<GetMenusQueryResultItem> models, List<GetMenusQueryResultItem> all, List<Guid> roleMenuIds)
        {
            foreach (var item in models)
            {
                item.IsChecked = roleMenuIds.Contains(item.Id);
                item.Children = all.Where(it => it.ParentId == item.Id).ToList();
                if (item.Children.IsNotNull())
                {
                    LoopChildrens(item.Children, all, roleMenuIds);
                }
            }
        }
    }
}