[ApiController]
[Route("api/[controller]")]
public class BooksController : ControllerBase
{
    private readonly LibraryContext _context;

    public BooksController(LibraryContext context)
    {
        _context = context;
    }

    // GET: api/books
    [HttpGet]
    public async Task<ActionResult<IEnumerable<Book>>> GetBooks()
    {
        return await _context.Books
            .Include(b => b.Author)
            .Include(b => b.Genre)
            .ToListAsync();
    }

    // GET: api/books/5
    [HttpGet("{id}")]
    public async Task<ActionResult<Book>> GetBook(int id)
    {
        var book = await _context.Books
            .Include(b => b.Author)
            .Include(b => b.Genre)
            .FirstOrDefaultAsync(b => b.Id == id);

        if (book == null)
            return NotFound();

        return book;
    }

    // POST: api/books
    [HttpPost]
    public async Task<ActionResult<Book>> CreateBook(Book book)
    {
        _context.Books.Add(book);
        await _context.SaveChangesAsync();
        return CreatedAtAction(nameof(GetBook), new { id = book.Id }, book);
    }

    // PUT: api/books/5
    [HttpPut("{id}")]
    public async Task<IActionResult> UpdateBook(int id, Book book)
    {
        if (id != book.Id)
            return BadRequest();

        _context.Entry(book).State = EntityState.Modified;

        try
        {
            await _context.SaveChangesAsync();
        }
        catch (DbUpdateConcurrencyException)
        {
            if (!BookExists(id))
                return NotFound();
            else
                throw;
        }

        return NoContent();
    }

    // DELETE: api/books/5
    [HttpDelete("{id}")]
    public async Task<IActionResult> DeleteBook(int id)
    {
        var book = await _context.Books.FindAsync(id);
        if (book == null)
            return NotFound();

        _context.Books.Remove(book);
        await _context.SaveChangesAsync();
        return NoContent();
    }

    private bool BookExists(int id) => _context.Books.Any(e => e.Id == id);
}