let trendingBooks = [];
let currentHeroIndex = 0;
let heroInterval;

window.addEventListener('scroll', () => {
    const nav = document.getElementById('navbar');
    if (window.scrollY > 50) nav.classList.add('scrolled');
    else nav.classList.remove('scrolled');
});

const searchInput = document.getElementById('search-input');
const searchResults = document.getElementById('search-results');
let searchTimeout;

searchInput.addEventListener('input', (e) => {
    const query = e.target.value;
    clearTimeout(searchTimeout);
    
    if (query.length < 2) {
        searchResults.classList.remove('active');
        searchResults.innerHTML = '';
        searchInput.style.borderRadius = '99px';
        return;
    }

    searchTimeout = setTimeout(() => {
        fetchBookSearch(query);
    }, 300);
});

document.addEventListener('click', (e) => {
    if (!e.target.closest('.search-wrapper')) {
        searchResults.classList.remove('active');
        searchInput.style.borderRadius = '99px';
    }
});

async function fetchBookSearch(query) {
    try {
        const res = await fetch(`/api/search/books?q=${encodeURIComponent(query)}`);
        const data = await res.json();
        renderSearchResults(data.results || []);
    } catch (err) { 
        console.error("Search Error:", err); 
        renderSearchResults([]);
    }
}

function createSlug(text) {
    if (!text) return '';
    return text
        .toLowerCase()
        .trim()
        .replace(/-/g, '--')
        .replace(/\s+/g, '-')
        .replace(/[^a-z0-9\-]/g, '');
}

function renderSearchResults(results) {
    searchResults.innerHTML = '';

    if (!results || results.length === 0) {
        searchResults.innerHTML = '<div style="padding:1rem; color:#888; text-align:center">No results found</div>';
    } else {
        results.forEach(book => {
            const title = book.title.english || book.title.romaji || "Unknown";
            const img = (book.coverImage && (book.coverImage.medium || book.coverImage.large)) || '';
            const rating = book.averageScore ? `${book.averageScore}%` : 'N/A';
            const year = book.seasonYear || (book.startDate ? book.startDate.year : '') || '????';
            const format = book.format || 'MANGA';
            let href;

            if (book.isExtensionResult) {
                const titleSlug = createSlug(title);
                href = `/book/${book.extensionName}/${titleSlug}`;
            } else {
                href = `/book/${book.id}`;
            }

            const extName = book.extensionName.charAt(0).toUpperCase() + book.extensionName.slice(1);
            const extPill = book.isExtensionResult
                ? `<span>${extName}</span>`
                : '';

            const item = document.createElement('a');
            item.className = 'search-item';
            item.href = href;

            item.innerHTML = `
                <img src="${img}" class="search-poster" alt="${title}">
                <div class="search-info">
                    <div class="search-title">${title}</div>
                    <div class="search-meta">
                        <span class="rating-pill">${rating}</span>
                        <span>• ${year}</span>
                        <span>• ${format}</span>
                        ${extPill}
                    </div>
                </div>
            `;

            searchResults.appendChild(item);
        });
    }

    searchResults.classList.add('active');
    searchInput.style.borderRadius = '12px 12px 0 0';
}

function scrollCarousel(id, direction) {
    const container = document.getElementById(id);
    if(container) {
        const scrollAmount = container.clientWidth * 0.75;
        container.scrollBy({ left: direction * scrollAmount, behavior: 'smooth' });
    }
}

async function init() {
    try {
        const res = await fetch('/api/books/trending');
        const data = await res.json();
        
        if (data.results && data.results.length > 0) {
            trendingBooks = data.results;
            updateHeroUI(trendingBooks[0]);
            renderList('trending', trendingBooks);
            startHeroCycle();
        }

        const resPop = await fetch('/api/books/popular');
        const dataPop = await resPop.json();
        if (dataPop.results) renderList('popular', dataPop.results);

    } catch (e) {
        console.error("Books Error:", e);
    }
}

function startHeroCycle() {
    if(heroInterval) clearInterval(heroInterval);
    heroInterval = setInterval(() => {
        if(trendingBooks.length > 0) {
            currentHeroIndex = (currentHeroIndex + 1) % trendingBooks.length;
            updateHeroUI(trendingBooks[currentHeroIndex]);
        }
    }, 8000);
}

function updateHeroUI(book) {
    if(!book) return;
    const title = book.title.english || book.title.romaji;
    const desc = book.description || "No description available.";
    const poster = (book.coverImage && (book.coverImage.extraLarge || book.coverImage.large)) || '';
    const banner = book.bannerImage || poster;
    
    document.getElementById('hero-title').innerText = title;
    document.getElementById('hero-desc').innerHTML = desc;
    document.getElementById('hero-score').innerText = (book.averageScore || '?') + '% Score';
    document.getElementById('hero-year').innerText = (book.startDate && book.startDate.year) ? book.startDate.year : '????';
    document.getElementById('hero-type').innerText = book.format || 'MANGA';
    
    const heroPoster = document.getElementById('hero-poster');
    if(heroPoster) heroPoster.src = poster;
    
    const bg = document.getElementById('hero-bg-media');
    if(bg) bg.src = banner;

    const readBtn = document.getElementById('read-btn');
    if (readBtn) {
        readBtn.onclick = () => window.location.href = `/book/${book.id}`;
    }
}

function renderList(id, list) {
    const container = document.getElementById(id);
    container.innerHTML = '';
    
    list.forEach(book => {
        const title = book.title.english || book.title.romaji;
        const cover = book.coverImage ? book.coverImage.large : '';
        const score = book.averageScore || '--';
        const type = book.format || 'Book';

        const el = document.createElement('div');
        el.className = 'card';
        el.onclick = () => {
            window.location.href = `/book/${book.id}`;
        };
        el.innerHTML = `
            <div class="card-img-wrap"><img src="${cover}" loading="lazy"></div>
            <div class="card-content">
                <h3>${title}</h3>
                <p>${score}% • ${type}</p>
            </div>
        `;
        container.appendChild(el);
    });
}

init();