dotNetStudyWithGPT/MySolution/ToDoApp/Service/ItemService.cs

using Microsoft.EntityFrameworkCore;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using ToDoApp.Context;
using ToDoApp.Model;
using ToDoApp.Utility;

namespace ToDoApp.Service
{
    public class ItemService
    {
        public static ItemService Instance { get; set; } = new ItemService();

        public List<Item> FindAllItems(int userId)
        {
            using (var context = new ToDoContext())
            {
                return context.Items.Where(i => i.UserId == userId).ToList();
            }
        }

        public List<Item> FindAllItems(User user)
        {
            using (var context = new ToDoContext())
            {
                return context.Items.Include(i => i.User).Where(i => i.User == user).ToList();
            }
        }

        public List<Item> FindAllNotCompletedItems(int userId)
        {
            using (var context = new ToDoContext())
            {
                return context.Items.Include(i => i.User).Where(i => i.UserId == userId && i.IsCompleted != false).ToList();
            }
        }

        public List<Item> FindAllNotCompletedItems(User user)
        {
            using (var context = new ToDoContext())
            {
                return context.Items.Include(i => i.User).Where(i => i.User == user && i.IsCompleted == false).ToList();
            }
        }

        public Item? FindItem(int itemId)
        {
            using (var context = new ToDoContext())
            {
                return context.Items.FirstOrDefault(i => i.Id == itemId);
            }
        }

        public Item? FindItem(Item item)
        {
            return FindItem(item.Id);
        }

        public void CreateItem(Item item)
        {
            using (var context = new ToDoContext())
            {
                item.CreateDate = DateTime.Now;
                context.Items.Add(item);
                context.SaveChanges();
            }
        }

        public void UpdateItem(Item item)
        {
            using (var context = new ToDoContext())
            {
                Item? original = context.Items.Find(item.Id);
                if (original == null)
                    return;

                original.Title = item.Title;
                original.Description = item.Description;
                original.DueDate = item.DueDate;
                original.IsToday = item.IsToday;
                original.IsCompleted = item.IsCompleted;

                context.SaveChanges();
            }
        }

        public void RemoveItem(int itemId)
        {
            using (var context = new ToDoContext())
            {
                Item? item = context.Items.Find(itemId);
                if (item == null) 
                    return;

                context.Remove(item);
                context.SaveChanges();
            }
        }

        public void RemoveItem(Item item)
        {
            RemoveItem(item.Id);
        }
    }
}