Lab: Working with Queries in Django

# 1.    Books Finder

def find_books_by_genre_and_language(book_genre, book_language):
    found_books = Book.objects.filter(genre=book_genre, language=book_language)

    return found_books

# print(find_books_by_genre_and_language("Romance", "English"))
# print(find_books_by_genre_and_language("Poetry", "Spanish"))
# print(find_books_by_genre_and_language("Mystery", "English"))



# 2.    Find Authors' Nationalities

def find_authors_nationalities():
    authors = Author.objects.exclude("nationality"=None)

    result = [
        f"{author.first_name} {author.last_name} is {author.nationality}" for author in authors
    ]

    return "\n".join(result)

# print(find_authors_nationalities())


# 3.    Order Books by Year

def order_books_by_year():
    ordered_books = Book.objects.order_by("publication_year", "title")

    result = [
        f"{book.publication_year} year: {book.title} by {book.author}" for book in ordered_books
    ]


    return "\n".join(result)

# print(order_books_by_year())


# 4.    Delete Review by ID

def delete_review_by_id(review_id):
    review = Review.objects.get(id=review_id)
    review.delete()

    return f"Review by {review.reviewer_name} was deleted"

# print(delete_review_by_id(4))
# print(delete_review_by_id(1))
# print(delete_review_by_id(8))


# 5.    Filter Authors by Nationalities

def filter_authors_by_nationalities(nationality):
    authors = Author.objects.filter(nationality=nationality).order_by("first_name", "last_name")

    result = [
        author.biography if author.biography is not None else f"{author.first_name} {author.last_name}" for author in authors
    ]

    return "\n".join(authors)

# print("American authors:")
# print(filter_authors_by_nationalities('American'))
# print()
# print("British authors:")
# print(filter_authors_by_nationalities('British'))
# print()
# print("Authors with no nationalities:")
# print(filter_authors_by_nationalities(None))


# 6.    Filter Authors by Birth Year

def filter_authors_by_birth_year(first_year, second_year):
    authors = Author.objects.filter(birth_date__year__range=(first_year, last_name)).order_by("-birth_date"))

    result = [
        f"{author.birth_date}: {author.first_name} {author.last_name}" for author in authors
    ]


    return "\n".join(result)

# print("Authors born between 1980 and 2000:")
# print(filter_authors_by_birth_year(1980, 2000))
# print()
# print("Authors born between 1950 and 1960:")
# print(filter_authors_by_birth_year(1950, 1960))
# print()
# print("Authors born between 2000 and 2010:")
# print(filter_authors_by_birth_year(2000, 2010))

# 7.    Change Reviewer's Name

def change_reviewer_name(reviewer_name, new_name):
    (Review.objects
    .filter(reviewer_name=reviewer_name)
    .update(reviewer_name=new_name))
    result = Review.objects.all()
    return result

# print("Change Alice Johnson to A.J.:")
# print(change_reviewer_name("Alice Johnson", "A.J."))
# print()
# print("Change Bob Wilson to Bobby W.:")
# print(change_reviewer_name("Bob Wilson", "Bobby W."))
# print()
# print("Change A.J. to A. Johnson:")
# print(change_reviewer_name("A.J.", "A. Johnson"))