function selectLibrary(libraryId: string): void {
    localStorage.setItem('selectedLibrary', libraryId);

    document.querySelectorAll('.library-item').forEach(el => {
        el.classList.remove('ring-2');
        el.classList.remove('ring-accent');
    });

    const selected = document.querySelector(`[data-library-id="${libraryId}"]`);
    if (selected) {
        selected.classList.add('ring-2');
        selected.classList.add('ring-accent');
    }

    loadBookshelf(libraryId);
}

async function loadBookshelf(libraryId: string): Promise<void> {
    const token = localStorage.getItem('token');
    if (!token) return;

    try {
        const response = await fetch(`/api/libraries/${libraryId}/books`, {
            headers: { 'Authorization': `Bearer ${token}` }
        });

        if (response.ok) {
            const data = await response.json();
            renderBooks(data.books || []);
        }
    } catch (error) {
        console.error('Failed to load bookshelf:', error);
    }
}

function renderBooks(books: unknown[]): void {
    const container = document.getElementById('books-grid');
    if (!container) return;

    if (books.length === 0) {
        container.innerHTML = '<p class="text-center p-8" style="color: var(--text-secondary)">No books in this library</p>';
        return;
    }

    container.innerHTML = books.map((book: any) => `
        <div class="book-card p-3 rounded-lg border transition-transform hover:scale-105 cursor-pointer"
             style="background-color: var(--bg-secondary); border-color: var(--border)"
             onclick="window.selectBook('${book.id}')">
            ${book.cover_image_path ?
                `<img src="/covers/${book.cover_image_path}" alt="${book.title}" class="w-full h-48 object-cover rounded mb-2">` :
                `<div class="w-full h-48 rounded mb-2 flex items-center justify-center" style="background-color: var(--bg-primary)">
                    <span class="text-4xl">📖</span>
                </div>`
            }
            <h3 class="font-medium text-sm truncate" style="color: var(--text-primary)">${book.title}</h3>
            <p class="text-xs truncate" style="color: var(--text-secondary)">${book.author || 'Unknown Author'}</p>
        </div>
    `).join('');
}

function selectBook(bookId: string): void {
    localStorage.setItem('selectedBook', bookId);
    window.location.href = `/books/${bookId}`;
}

function changePage(page: number): void {
    const libraryId = localStorage.getItem('selectedLibrary');
    if (!libraryId) return;

    const offset = (page - 1) * 50;
    loadBookshelfPaginated(libraryId, offset);
}

async function loadBookshelfPaginated(libraryId: string, offset: number): Promise<void> {
    const token = localStorage.getItem('token');
    if (!token) return;

    try {
        const response = await fetch(`/api/libraries/${libraryId}/books?offset=${offset}&limit=50`, {
            headers: { 'Authorization': `Bearer ${token}` }
        });

        if (response.ok) {
            const data = await response.json();
            renderBooks(data.books || []);
            updatePagination(data.total, offset);
        }
    } catch (error) {
        console.error('Failed to load bookshelf:', error);
    }
}

function updatePagination(total: number, offset: number): void {
    const container = document.getElementById('pagination');
    if (!container) return;

    const limit = 50;
    const currentPage = Math.floor(offset / limit) + 1;
    const totalPages = Math.ceil(total / limit);

    if (totalPages <= 1) {
        container.innerHTML = '';
        return;
    }

    container.innerHTML = `
        <div class="flex justify-center space-x-2">
            ${currentPage > 1 ? `<button onclick="window.changePage(${currentPage - 1})" class="btn-secondary px-3 py-1 rounded">Previous</button>` : ''}
            <span class="px-3 py-1" style="color: var(--text-secondary)">Page ${currentPage} of ${totalPages}</span>
            ${currentPage < totalPages ? `<button onclick="window.changePage(${currentPage + 1})" class="btn-secondary px-3 py-1 rounded">Next</button>` : ''}
        </div>
    `;
}

(window as any).selectLibrary = selectLibrary;
(window as any).loadBookshelf = loadBookshelf;
(window as any).selectBook = selectBook;
(window as any).changePage = changePage;