/// <summary>
/// Gives instance of book to the subscriber and sets a specific time
/// </summary>
/// <param name="subscriber"></param>
/// <param name="book"></param>
public void SubscribeTheBookToTheSubscriber(Subscriber subscriber, Book book, DateTime subscribingTime)
{
if (subscriber == null)
{
throw new ArgumentNullException("subsriber", "Sibscriber is null");
}
if (book == null)
{
throw new ArgumentNullException("book", "Book is null");
}
if (subscriber.GetTakenBooks().Count() >= 5)
{
throw new SubscribingException("У абонента превышен лимит книг", subscriber, book);
}
if (subscriber.GetOverdueTakenBooks().Any())
{
throw new SubscribingException("У абонента есть просроченные книги", subscriber, book);
}
if (book.BookSubscriber != null)
{
throw new SubscribingException("Книга уже у другого абонента", subscriber, book);
}
if (book.Rare && subscriber.GetRareBooks().Any())
{
throw new SubscribingException("У абонента уже есть редкая книга", subscriber, book);
}
book.Subscribe(subscriber, subscribingTime);
subscriber.AddBook(book);
BookStateChanged?.Invoke(this, new BookStateChangedEventArgs(book, BusinessLayer.BookStateChanged.Subscribing, true, "Книга выдана абоненту."));
//BookStateChanged?.Invoke(this, new BookStateChangedEventArgs(book, BusinessLayer.BookStateChanged.Subscribing, false, "Книга не выдана абоненту, так как редкая книга уже имеется у абонента."));
}
public BookStateChangedEventArgs(Book book, BookStateChanged bookStateShanged, bool isExecuted, string message)
{
Book = book;
BookStateChanged = bookStateShanged;
IsExecuted = isExecuted;
Message = message;
}
/// <summary>
/// Gets instance of the book from the subscriber and indocated, that this book in library
/// </summary>
/// <param name="subscriber"></param>
/// <param name="book"></param>
public void UnsubscribeTheBookFromTheSubscriber(Subscriber subscriber, Book book)
{
if (subscriber == null)
{
throw new ArgumentNullException("subsriber", "Sibscriber is null");
}
if (book == null)
{
throw new ArgumentNullException("book", "Book is null");
}
if (!subscriber.GetTakenBooks().Any(x => x == book))
{
//BookStateChanged?.Invoke(this, new BookStateChangedEventArgs(book, BusinessLayer.BookStateChanged.Unsubscribing, false, "Книга не принята от абонента"));
throw new UnsubscribingException("Subscriber does not have trasmitted book in taken books", subscriber, book);
}
book.Unsubscribe();
subscriber.RemoveBook(book);
BookStateChanged?.Invoke(this, new BookStateChangedEventArgs(book, BusinessLayer.BookStateChanged.Unsubscribing, true, "Книга принята от абонента"));
}
