using ComputerShopContracts.BindingModels;
using ComputerShopContracts.BusinessLogicContracts;
using ComputerShopContracts.SearchModels;
using ComputerShopContracts.StorageContracts;
using ComputerShopContracts.ViewModels;
using Microsoft.Extensions.Logging;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ComputerShopBusinessLogic.BusinessLogics
{
	public class UserLogic : IUserLogic
	{
		private readonly ILogger _logger;
		private readonly IUserStorage _userStorage;

		public UserLogic(ILogger<IUserLogic> logger, IUserStorage userStorage)
		{
			_logger = logger;
			_userStorage = userStorage;
		}
		public List<UserViewModel>? ReadList(UserSearchModel? model)
		{
			var list = model == null ? _userStorage.GetFullList() : _userStorage.GetFilteredList(model);
			if (list == null)
			{
				_logger.LogWarning("Null list user");
				return null;
			}
			return list;
		}

		public UserViewModel? ReadElement(UserSearchModel model)
		{
			if (model == null)
			{
				throw new ArgumentNullException(nameof(model));
			}
			var element = _userStorage.GetElement(model);
			if (element == null)
			{
				_logger.LogWarning("ReadElement user not found");
				return null;
			}
			return element;
		}

		public bool Create(UserBindingModel model)
		{
			CheckModel(model);
			if (_userStorage.Insert(model) == null)
			{
				_logger.LogWarning("Insert failed");
				return false;
			}
			return true;
		}

		public bool Update(UserBindingModel model)
		{
			CheckModel(model);
			if (_userStorage.Update(model) == null)
			{
				_logger.LogWarning("Update failed");
				return false;
			}
			return true;
		}

		public bool Delete(UserBindingModel model)
		{
			CheckModel(model, false);
			if (_userStorage.Delete(model) == null)
			{
				_logger.LogWarning("Delete failed");
				return false;
			}
			return true;
		}

		private void CheckModel(UserBindingModel model, bool withParams = true)
		{
			if (model == null)
			{
				throw new ArgumentNullException(nameof(model));
			}
			if (!withParams)
			{
				return;
			}
			if (string.IsNullOrEmpty(model.Login))
			{
				throw new ArgumentNullException("Логин не существует", nameof(model.Login));
			}
			if (string.IsNullOrEmpty(model.Password))
			{
				throw new ArgumentNullException("Пароль не существует", nameof(model.Password));
			}
			if (string.IsNullOrEmpty(model.Email))
			{
				throw new ArgumentNullException("Почта не существует", nameof(model.Email));
			}
			
			var user1 = _userStorage.GetElement(new UserSearchModel
			{
				Login = model.Login
			});

			if (user1 != null && user1.Id != model.Id)
			{
				throw new InvalidOperationException("Логин занят");
			}

			var user2 = _userStorage.GetElement(new UserSearchModel
			{
				Email = model.Email
			});

			if (user2 != null && user2.Id != model.Id) {
				throw new InvalidOperationException("Почта занята");
			}
		}
	}
}