protected async Task <int> GetTotalPages(
BooksQuery request,
bool onlyAvailable = true,
int?authorId = default,
CancellationToken cancellationToken = default)
{
var bookSpecification = this.GetBookSpecification(request, onlyAvailable);
var authorSpecification = this.GetAuthorSpecification(request, authorId);
var totalBooks = await this.bookRepository.Total(
bookSpecification,
authorSpecification,
cancellationToken);
return((int)Math.Ceiling((double)totalBooks / BooksPerPage));
}
protected async Task <IEnumerable <TOutputModel> > GetBookListings <TOutputModel>(
BooksQuery request,
bool onlyAvailable = true,
int?authorId = default,
CancellationToken cancellationToken = default)
{
var bookSpecification = this.GetBookSpecification(request, onlyAvailable);
var authorSpecification = this.GetAuthorSpecification(request, authorId);
var searchOrder = new BooksSortOrder(request.SortBy, request.Order);
var skip = (request.Page - 1) * BooksPerPage;
return(await this.bookRepository.GetBookListings <TOutputModel>(
bookSpecification,
authorSpecification,
searchOrder,
skip,
take : BooksPerPage,
cancellationToken));
}
private Specification <Book> GetBookSpecification(BooksQuery request, bool onlyAvailable) => new BookByPublisherSpecification(request.Publisher) .And(new BookByPriceSpecification(request.MinPrice, request.MaxPrice)) .And(new BookOnlyAvailableSpecification(onlyAvailable));
private Specification <Author> GetAuthorSpecification(BooksQuery request, int?authorId) => new AuthorByIdSpecification(authorId) .And(new AuthorByNameSpecification(request.Author));