using System;

using System.Linq;

using System.Collections.Generic;

//using Microsoft.EntityFrameworkCore;

using AutoMapper;   

using Moq;

​

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello Library");

​

        MockLibrary mockLibrary = new MockLibrary();

        var library = mockLibrary.Data();

        var libraryDto = mockLibrary.DataDto();

        var myProfile = new AutoMapping();

        var configuration = new MapperConfiguration(cfg => cfg.AddProfile(myProfile));

        var _mapper = new Mapper(configuration);

        /*

        libraryDto.Books.ForEach(bookDto => {

            //Console.WriteLine($"library book: {bookDto.BookId}, Author count: {bookDto.BookAuthors.Count}");

            var mappedBook = _mapper.Map<Book>(bookDto);

            //Console.WriteLine($"mapped book: {mappedBook.BookId}, Author count: {mappedBook.BookAuthors.Count}");

            mappedBook.BookAuthors.ForEach(bk => {

                Console.WriteLine($"mapped book {bk.BookId} author: {bk.AuthorId}");

            });

        });

        var mappedBooks = _mapper.Map<List<Book>>(libraryDto.Books);

        mappedBooks.ForEach(book => {

            Console.WriteLine($"library book: {book.BookId}, Author count: {book.BookAuthors.Count}");

        });

        */

        library.Books.ForEach(book => {

            //Console.WriteLine($"library book: {book.BookId}, Author count: {book.BookAuthors.Count}");

            var mappedBook = _mapper.Map<BookViewModel>(book);

            Console.WriteLine($"mapped book: {mappedBook.BookId}, Author count: {mappedBook.Authors.Count}");

            mappedBook.Authors.ForEach(bk => {

                Console.WriteLine($"mapped book author: {bk.AuthorId}, name: {bk.AuthorName}");

​

            });

        });

        Console.WriteLine("Library mapped data");

        //var mappedBooks = _mapper.Map<BookViewModel>(library.Books);

    }

}

​

public class AutoMapping : Profile{

    public AutoMapping(){

        CreateMap<Book, BookViewModel>() // Book -> BookViewModel

​

            .ForMember(dest => dest.Authors, opt => opt.MapFrom(src => src.BookAuthors

                                                          //.Select(bookAuthor => bookAuthor.Author)))

                                                          .Select(bookAuthor => new Author { AuthorId = bookAuthor.AuthorId})))

​

            .ReverseMap()               // BookViewModel -> Book

            .PreserveReferences()

            .ForMember(dest => dest.BookAuthors, opt => opt.MapFrom(src => src.Authors

                                                              .Select(author => 

                                                                      new { src.BookId, Book = src, author.AuthorId, Author = author })))

            ;

​

        CreateMap<Author, AuthorViewModel>() // Author -> AuthorViewModel

            .ReverseMap()                    // AuthorViewModel -> Author

            ;

    }

}

​

public class Book

{

    public int BookId { get; set; }

    public List<BookAuthor> BookAuthors { get; set; } = new List<BookAuthor>();

}

public class Author

{

    public int AuthorId { get; set; }

    public string AuthorName { get; set; }

    public List<BookAuthor> BookAuthors { get; set; } = new List<BookAuthor>();

}

 public class BookAuthor

{

    public int BookId { get; set; }

    public Book Book { get; set; }

    public int AuthorId { get; set; }

    public Author Author { get; set; }

}

public class BookViewModel

{

    public int BookId { get; set; }

    public virtual List<AuthorViewModel> Authors { get; set; } = new List<AuthorViewModel>();   

}

public class AuthorViewModel

{

    public int AuthorId { get; set; }

    public string AuthorName { get; set; }

}

public class MockLibrary {

    public LibraryContext libraryContext {get;set;} = new LibraryContext();

    public LibraryContext libraryContextDto {get;set;} = new LibraryContext();

    public LibraryContext Data(){

        var book1 = new Book { BookId = 1 };

        var book2 = new Book { BookId = 2 };

        var book3 = new Book { BookId = 3 };

        var book4 = new Book { BookId = 4 };

        var author1 = new Author { AuthorId = 1, AuthorName = "CBZ" };

        var author2 = new Author { AuthorId = 2, AuthorName = "ABS" };

        book1.BookAuthors.Add(new BookAuthor { BookId = book1.BookId, AuthorId = author1.AuthorId });

        book2.BookAuthors.Add(new BookAuthor { BookId = book2.BookId, AuthorId = author1.AuthorId });

        book3.BookAuthors.Add(new BookAuthor { BookId = book3.BookId, AuthorId = author1.AuthorId });

        book3.BookAuthors.Add(new BookAuthor { BookId = book3.BookId, AuthorId = author2.AuthorId });

        book4.BookAuthors.Add(new BookAuthor { BookId = book4.BookId, AuthorId = author2.AuthorId });

​

        libraryContext.Books.AddRange(new List<Book> {book1, book2, book3, book4});

        libraryContext.Authors.AddRange(new List<Author> {author1, author2});

        return libraryContext;

    }

        public LibraryContext DataDto(){

            var book6 = new Book { BookId = 6 };

            var book7 = new Book { BookId = 7 };

            var book8 = new Book { BookId = 8 };

            var book9 = new Book { BookId = 9 };

            var author1 = new Author { AuthorId = 1, AuthorName = "CBZ" };

            var author2 = new Author { AuthorId = 2, AuthorName = "ABS" };

​

            book6.BookAuthors.Add(new BookAuthor { BookId = book6.BookId, AuthorId = author1.AuthorId });

            book7.BookAuthors.Add(new BookAuthor { BookId = book7.BookId, AuthorId = author1.AuthorId });

            book8.BookAuthors.Add(new BookAuthor { BookId = book8.BookId, AuthorId = author1.AuthorId });

            book8.BookAuthors.Add(new BookAuthor { BookId = book8.BookId, AuthorId = author2.AuthorId });

            book9.BookAuthors.Add(new BookAuthor { BookId = book9.BookId, AuthorId = author2.AuthorId });

​

            libraryContextDto.Books.AddRange(new List<Book> {book6, book7, book8, book9});

            libraryContextDto.Authors.AddRange(new List<Author> {author1, author2});

            return libraryContextDto;

    }

}

​

public class LibraryContext

{

    public List<Book> Books { get; set; } = new List<Book>();

    public List<Author> Authors { get; set; } = new List<Author>();

}