bookshelfmanager.py

from typing import List
import json
from typing import Optional
from book import Book
import random
from pathlib import Path
from bookwidth import BookWidth


class BookshelfManager:
    """Manages a collection of books and their visualization."""

    def __init__(self, data_file: Path):
        self.data_file = data_file
        self.books: List[Book] = []

    def load_books(self) -> List[Book]:
        """Load books from JSON file."""
        if not self.data_file.exists():
            print(f"No existing bookshelf found at {self.data_file}")
            return []

        try:
            with open(self.data_file, 'r') as f:
                data = json.load(f)

            self.books = [Book.from_dict(book_data) for book_data in data]
            print(f"Loaded {len(self.books)} books from {self.data_file}")
            return self.books

        except (json.JSONDecodeError, KeyError) as e:
            print(f"Error loading books from {self.data_file}: {e}")
            return []

    def save_books(self) -> bool:
        """Save books to JSON file."""
        try:
            self.data_file.parent.mkdir(parents=True, exist_ok=True)

            with open(self.data_file, 'w') as f:
                json.dump([book.to_dict() for book in self.books], f, indent=2)

            print(f"Saved {len(self.books)} books to {self.data_file}")
            return True

        except Exception as e:
            print(f"Error saving books to {self.data_file}: {e}")
            return False

    def add_book_interactive(self) -> bool:
        """Interactively add a new book."""
        try:
            title = input("Enter book title: ").strip()
            if not title:
                print("Title cannot be empty")
                return False

            author = input("Enter author name: ").strip()
            if not author:
                print("Author cannot be empty")
                return False

            pages = self._get_pages_input()
            width = self._get_width_input()

            new_book = Book(title=title, author=author,
                            pages=pages, book_width=width)

            print(f"\nNew book: {new_book}")
            confirm = input("Add this book to the shelf? [y/N]: ").lower()

            if confirm == 'y':
                self.books.append(new_book)
                return self.save_books()
            else:
                print("Book not added")
                return False

        except KeyboardInterrupt:
            print("\nOperation cancelled")
            return False

    def _get_pages_input(self) -> int:
        """Get valid page count from user."""
        while True:
            try:
                pages = int(input("Number of pages: "))
                if pages > 0:
                    return pages
                print("Pages must be greater than 0")
            except ValueError:
                print("Please enter a valid number")

    def _get_width_input(self) -> BookWidth:
        """Get book width choice from user."""
        width_options = {
            '0': BookWidth.SMALL,
            '1': BookWidth.MEDIUM,
            '2': BookWidth.WIDE,
            '3': BookWidth.VERY_WIDE
        }

        print("\nBook width options:")
        print("0: Small")
        print("1: Medium")
        print("2: Wide")
        print("3: Very Wide")

        while True:
            choice = input("Choose width [1]: ").strip() or '1'
            if choice in width_options:
                return width_options[choice]
            print("Please enter 0, 1, 2, or 3")

    def link_books(self):
        """Set up linked list connections between books."""
        for i, book in enumerate(self.books):
            book.prev_book = self.books[i - 1] if i > 0 else None
            book.next_book = self.books[i +
                                        1] if i < len(self.books) - 1 else None

            if i > 0:
                book.x_start = random.randint(1, 11)

    def display_bookshelf(self, output_file: Optional[str] = None):
        """Display the bookshelf visualization."""
        if not self.books:
            print("No books to display. Add some books first!")
            return

        self.link_books()

        file_handle = None
        if output_file:
            try:
                file_handle = open(output_file, 'w')
            except Exception as e:
                print(f"Error opening output file {output_file}: {e}")
                return

        try:
            for book in reversed(self.books):
                book.print_book(file=file_handle)
        finally:
            if file_handle:
                file_handle.close()
                print(f"Bookshelf visualization saved to {output_file}")

    def reset_to_default(self) -> bool:
        """Reset bookshelf to default books."""
        default_books = []

        self.books = default_books
        return self.save_books()