using BookContract.BindingModels;
using BookContract.BusinessLogicContracts;
using BookContract.StorageContracts;
using BookContract.ViewModels;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace BookBusinessLogic.BusinessLogic
{
    public class HistoryLogic : IHistoryLogic
    {
        private readonly IHistoryStorage _historyStorage;

        public HistoryLogic(IHistoryStorage historyStorage)
        {
            _historyStorage = historyStorage;
        }

        public List<HistoryViewModel> Read(HistoryBindingModel model)
        {
            if(model == null)
            {
                return _historyStorage.GetFullList();
            }
            if (model.Id.HasValue) { 
                return new List<HistoryViewModel>
                {
                    _historyStorage.GetElement(model)
                };
            }
            return _historyStorage.GetHistoryByBookId(model.BookId);
        }

        public void CreateOrUpdate(HistoryBindingModel model)
        {
            var element = _historyStorage.GetElement(
               new HistoryBindingModel
               {
                   Id = model.Id,
               });
            if (element != null && element.Id != model.Id)
            {
                throw new Exception("Такая связь уже существует");
            }
            _historyStorage.Insert(model);
        }

        public void Delete(HistoryBindingModel model)
        {
            var element = _historyStorage.GetElement(new HistoryBindingModel
            {
                Id = model.Id
            });

            if (element == null)
            {
                throw new Exception("Навык не найден");
            }

            _historyStorage.Delete(model);
        }
    }
}