public IEnumerable <BookModel> GetBooks()
{
var books = Books.Get()?.ToList();
if (books == null || !books.Any())
{
return(Enumerable.Empty <BookModel>().ToList());
}
var pubHouseIds = books.Select(t => t.PubHouseId);
var pubHouses = PubHouses.Get().Where(t => pubHouseIds.Contains(t.PubHouseId));
var bookIds = books.Select(t => t.BookId);
var authors = BookAuthors.Get().Where(t => bookIds.Contains(t.BookId)).Join(Authors.Get(),
ba => ba.AuthorId,
a => a.AuthorId,
(ba, a) =>
new
{
ba.BookId,
author = a
});
var list = new List <BookModel>();
books.ForEach(t =>
{
var thisBookAuthors = authors.Where(a => a.BookId == t.BookId).Select(q => q.author).ToList();
var pubHouse = pubHouses.SingleOrDefault(p => p.PubHouseId == t.PubHouseId);
list.Add(new BookModel(t, thisBookAuthors, pubHouse));
});
return(list);
}
public void DeleteAuthor(long id)
{
if (BookAuthors.Get().Any(t => t.AuthorId == id))
{
throw new InvalidOperationException();
}
Authors.Delete(id);
}
public BookModel GetBook(long id)
{
var book = Books.GetById(id);
var pubHouse = book.PubHouseId.HasValue ? PubHouses.GetById(book.PubHouseId.Value) : null;
var authors = Authors.Get()
.Join(BookAuthors.Get().Where(q => q.BookId == book.BookId), a => a.AuthorId, ba => ba.AuthorId, (a, ba) =>
a).ToList();
var bookModel = new BookModel(book, authors, pubHouse);
return(bookModel);
}