using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using TaskTrackerContracts.BindingModels;
using TaskTrackerContracts.SearchModels;
using TaskTrackerContracts.StoragesContracts;
using TaskTrackerContracts.ViewModels;
using TaskTrackerDatabase.Models;

namespace TaskTrackerDatabase.Implements
{
    public class UserStorage : IUserStorage
    {
        public List<UserViewModel> GetFullList()
        {
            using var context = new TaskTrackerDatabase();
            return context.Users
                    .Select(x => x.GetViewModel)
                    .ToList();
        }

        public List<UserViewModel> GetFilteredList(UserSearchModel model)
        {
            if (string.IsNullOrEmpty(model.Email))
            {
                return new();
            }
            using var context = new TaskTrackerDatabase();
            return context.Users
                    .Where(x => x.Email.Contains(model.Email))
                    .Select(x => x.GetViewModel)
                    .ToList();
        }

        public UserViewModel? GetElement(UserSearchModel model)
        {
            if (string.IsNullOrEmpty(model.Email) && string.IsNullOrEmpty(model.Password) && !model.Id.HasValue)
            {
                return null;
            }
            using var context = new TaskTrackerDatabase();
            return context.Users.FirstOrDefault(x =>
            (!string.IsNullOrEmpty(model.Email) && x.Email == model.Email && !string.IsNullOrEmpty(model.Password) && x.Password == model.Password)
            || (model.Id.HasValue && x.Id == model.Id))?.GetViewModel;
        }

        public UserViewModel? Insert(UserBindingModel model)
        {
            var newUser = User.Create(model);
            if (newUser == null)
            {
                return null;
            }
            using var context = new TaskTrackerDatabase();
            context.Users.Add(newUser);
            context.SaveChanges();
            return newUser.GetViewModel;
        }

        public UserViewModel? Update(UserBindingModel model)
        {
            using var context = new TaskTrackerDatabase();
            var user = context.Users.FirstOrDefault(x => x.Id == model.Id);
            if (user == null)
            {
                return null;
            }
            user.Update(model);
            context.SaveChanges();
            return user.GetViewModel;
        }

        public UserViewModel? Delete(UserBindingModel model)
        {
            using var context = new TaskTrackerDatabase();
            var element = context.Users.FirstOrDefault(x => x.Id == model.Id);
            if (element != null)
            {
                context.Users.Remove(element);
                context.SaveChanges();
                return element.GetViewModel;
            }
            return null;
        }
    }
}