document.addEventListener('DOMContentLoaded', function() {
    const carousel = document.querySelector('.js-carousel');
    if (!carousel) return;

    const track = carousel.querySelector('.js-carousel-track');
    const slides = track.children;
    const dots = carousel.querySelectorAll('.js-dot');
    const prevBtn = carousel.querySelector('.js-carousel-prev');
    const nextBtn = carousel.querySelector('.js-carousel-next');

    let current = 0;
    const total = slides.length;
    let touchStartX = 0;
    let touchEndX = 0;

    function updateDisplay() {
        // 移动轨道
        track.style.transform = `translateX(-${current * 100}%)`;
        // 更新指示器
        dots.forEach((dot, i) => {
            if (i === current) {
                dot.classList.add('bg-white', 'w-6');
                dot.classList.remove('bg-white/50');
            } else {
                dot.classList.remove('bg-white', 'w-6');
                dot.classList.add('bg-white/50');
            }
        });
    }

    function next() {
        current = (current === total - 1) ? 0 : current + 1;
        updateDisplay();
    }

    function prev() {
        current = (current === 0) ? total - 1 : current - 1;
        updateDisplay();
    }

    // 自动轮播
    let autoPlay = setInterval(next, 5000);

    function resetTimer() {
        clearInterval(autoPlay);
        autoPlay = setInterval(next, 5000);
    }

    // 事件监听
    if (nextBtn) nextBtn.addEventListener('click', () => { next(); resetTimer(); });
    if (prevBtn) prevBtn.addEventListener('click', () => { prev(); resetTimer(); });

    dots.forEach(dot => {
        dot.addEventListener('click', () => {
            current = parseInt(dot.getAttribute('data-index'));
            updateDisplay();
            resetTimer();
        });
    });

    // --- 触摸滑动逻辑 ---
    carousel.addEventListener('touchstart', (e) => {
        touchStartX = e.changedTouches[0].screenX;
    }, { passive: true });

    carousel.addEventListener('touchend', (e) => {
        touchEndX = e.changedTouches[0].screenX;
        const distance = touchStartX - touchEndX;
        const minSwipeDistance = 50;

        if (Math.abs(distance) > minSwipeDistance) {
            if (distance > 0) next(); else prev();
            resetTimer();
        }
    }, { passive: true });

    // 初始化
    updateDisplay();
});