using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Primitives;
using OneOf;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using static LMS.Common.Enums.PermissionEnum;

namespace LMS.DAO.PermissionDAO
{
    public class PermissionBasicDao(ApplicationDbContext context)
    {
        private readonly ApplicationDbContext _context = context;

        /// <summary>
        /// 判断指定的ID的权限是不是存在
        /// </summary>
        /// <param name="id"></param>
        /// <returns></returns>
        public async Task<bool> CheckPermissionExistById(string id)
        {
            if (string.IsNullOrWhiteSpace(id))
            {
                return false;
            }
            return await _context.Permission.AnyAsync(x => x.Id == id);
        }

        /// <summary>
        /// 判断权限的PermissionCode是不是存在
        /// 通过判断是不是有传递ID , 判断是不是需要排除当前的数据
        /// </summary>
        /// <param name="permissionCode"></param>
        /// <param name="id"></param>
        /// <returns></returns>
        public async Task<bool> CheckPermissionCodeExist(string permissionCode, string id = null)
        {
            if (string.IsNullOrWhiteSpace(permissionCode))
            {
                throw new ArgumentNullException(nameof(permissionCode));
            }

            if (string.IsNullOrEmpty(id))
            {
                return await _context.Permission.AnyAsync(x => x.PermissionCode == permissionCode);
            }
            else
            {
                return await _context.Permission.AnyAsync(x => x.PermissionCode == permissionCode && x.Id != id);
            }
        }

        /// <summary>
        /// 检查对应分类的权限是不是存在
        /// </summary>
        /// <param name="type"></param>
        /// <param name="id"></param>
        /// <param name="pid">再修改的时候必传这个值，用于判断对应的关联ID是不是有其他的值，有的话不能修改</param>
        /// <returns></returns>
        /// <exception cref="NotImplementedException"></exception>
        public async Task<bool> CheckPermissionByTypeAndId(PType type, OneOf<string, long?> id, string pid = null)
        {
            if (id.IsT0)
            {
                if (type != PType.Machine)
                {
                    throw new Exception("请检查参数的对应关系");
                }
                if (!string.IsNullOrEmpty(pid))
                {
                    return await _context.Permission.AnyAsync(x => x.MachineId == id.AsT0 && x.Type == type && x.Id != pid);
                }
                else
                {
                    return await _context.Permission.AnyAsync(x => x.MachineId == id.AsT0 && x.Type == type);
                }
            }
            else if (id.IsT1)
            {
                if (type == PType.Machine)
                {
                    throw new Exception("请检查参数的对应关系");
                }
                if (id.AsT1 == null)
                {
                    return false;
                }
                if (!string.IsNullOrEmpty(pid))
                {
                    return type switch
                    {
                        PType.User => await _context.Permission.AnyAsync(x => x.UserId == id.AsT1 && x.Type == type && x.Id != pid),
                        PType.Role => await _context.Permission.AnyAsync(x => x.RoleId == id.AsT1 && x.Type == type && x.Id != pid),
                        PType.Machine => throw new Exception("请检查参数的对应关系"),
                        _ => throw new Exception("参数类型错误"),
                    };
                }
                else
                {
                    return type switch
                    {
                        PType.User => await _context.Permission.AnyAsync(x => x.UserId == id.AsT1 && x.Type == type),
                        PType.Role => await _context.Permission.AnyAsync(x => x.RoleId == id.AsT1 && x.Type == type),
                        PType.Machine => throw new Exception("请检查参数的对应关系"),
                        _ => throw new Exception("参数类型错误"),
                    };
                }
            }
            else
            {
                throw new Exception("参数类型错误");
            }
        }
    }
}