using CarShowroomContracts.BusinessLogic;
using CarShowroomContracts.StorageContracts;
using CarShowroomDataModels.Dtos;
using CarShowroomDataModels.SearchModel;
using CarShowroomDataModels.Views;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace CarShowroomBusinessLogic.BusinessLogic
{
    public class EmployeeLogic : IEmployeeLogic
    {
        private readonly IEmployeeStorage _employeeStorage;

        public EmployeeLogic(IEmployeeStorage storage)
        {
            _employeeStorage = storage;
        }

        public List<EmployeeView>? ReadList(EmployeeSearch? model)
        {
            var list = model == null ? _employeeStorage.GetFullList() : _employeeStorage.GetFilteredList(model);
            if (list == null)
            {
                return null;
            }
            return list;
        }

        public EmployeeView? ReadElement(EmployeeSearch model)
        {
            if (model == null)
            {
                throw new ArgumentNullException(nameof(model));
            }
            var element = _employeeStorage.GetElement(model);
            if (element == null)
            {
                return null;
            }
            return element;
        }

        public bool Create(EmployeeDto model)
        {
            CheckModel(model);
            if (_employeeStorage.Insert(model) == null)
            {
                return false;
            }
            return true;
        }

        public bool Update(EmployeeDto model)
        {
            CheckModel(model);
            if (_employeeStorage.Update(model) == null)
            {
                return false;
            }
            return true;
        }

        public bool Delete(EmployeeDto model)
        {
            CheckModel(model, false);
            if (_employeeStorage.Delete(model) == null)
            {
                return false;
            }
            return true;
        }

        private void CheckModel(EmployeeDto model, bool withParams = true)
        {
            if (model == null)
                throw new ArgumentNullException(nameof(model));
            if (!withParams)
                return;
            if (string.IsNullOrEmpty(model.Name))
                throw new InvalidOperationException();
            if (string.IsNullOrEmpty(model.Email))
                throw new InvalidOperationException();
            if (string.IsNullOrEmpty(model.Password))
                throw new InvalidOperationException();
            var element = _employeeStorage.GetElement(new EmployeeSearch
            {
                Email = model.Email,
            });
            if (element != null && element.Id != model.Id)
                throw new InvalidOperationException();
        }
    }
}