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

namespace BookBusinessLogic.BusinessLogic
{
    public class BookLogic : IBookLogic
    {
        private readonly IBookStorage _bookStorage;

        public BookLogic(IBookStorage bookStorage)
        {
            _bookStorage = bookStorage;
        }

        public void CreateOrUpdate(BookBindingModel model)
        {
            var element = _bookStorage.GetElement(new BookBindingModel { Title = model.Title });
            if (element != null && element.Id != model.Id) {
                throw new Exception("Книги с таким названием тут нет");
            }
            if (model.Id.HasValue)
            {
                _bookStorage.Update(model);
            }
            else
            {
                _bookStorage.Insert(model);
            }
        }

        public void Delete(BookBindingModel model)
        {
            var element = _bookStorage.GetElement(new BookBindingModel { Title = model.Title });
            if (element == null)
            {
                throw new Exception("Книги с таким названием тут нет");
            }
            _bookStorage.Delete(model);
        }

        public List<BookViewModel> Read(BookBindingModel model)
        {
            if(model == null)
                return _bookStorage.GetFullList();
            if (model.Id.HasValue) {
                return new List<BookViewModel> {
                    _bookStorage.GetElement(model)
                };
            }
            return _bookStorage.GetFullList();
        }
    }
}