/**
 * Product Discount Countdown Module
 *
 * This script initializes countdown timers on the product page.
 * It handles the initial page load and the dynamic updates that occur
 * when a customer changes a product combination (attribute).
 */

// A global array to keep track of our active timer intervals.
// This is crucial for cleanup when the product block is updated via AJAX.
let productCountdownIntervals = [];

/**
 * Scans the DOM for countdown containers and initializes them.
 * This function is designed to be called on page load and after AJAX updates.
 */
function initializeProductCountdowns() {
  // 1. Clear any previously running timers.
  // This prevents multiple timers from running after a product combination change.
  productCountdownIntervals.forEach(intervalId => clearInterval(intervalId));
  productCountdownIntervals = [];

  // 2. Find all countdown containers on the page that need to be processed.
  const countdownContainers = document.querySelectorAll('.product-countdown-container');

  countdownContainers.forEach(container => {
    // Check if this specific container has already been initialized to avoid race conditions.
    if (container.dataset.initialized === 'true') {
        return;
    }

    const timerElement = container.querySelector('.countdown-timer');
    if (!timerElement) return;

    // Mark as initialized
    container.dataset.initialized = 'true';

    const targetTimestamp = parseInt(container.dataset.timestamp, 10);
    const onExpireAction = container.dataset.onExpire;
    const expiredText = container.dataset.expiredText;
    
    // Get translated units from hidden spans
    const units = {
        day: container.querySelector('[data-unit="day"]').textContent,
        days: container.querySelector('[data-unit="days"]').textContent,
        hr: container.querySelector('[data-unit="hr"]').textContent,
        min: container.querySelector('[data-unit="min"]').textContent,
        sec: container.querySelector('[data-unit="sec"]').textContent
    };

    function updateTimer() {
        const now = Math.floor(new Date().getTime() / 1000);
        const diff = targetTimestamp - now;

        if (diff <= 0) {
            clearInterval(interval);
            handleExpiry();
            return;
        }

        const d = Math.floor(diff / (60 * 60 * 24));
        const h = Math.floor((diff % (60 * 60 * 24)) / (60 * 60));
        const m = Math.floor((diff % (60 * 60)) / 60);
        const s = Math.floor(diff % 60);

        const parts = [];
        if (d > 0) {
            parts.push(`${d} ${d > 1 ? units.days : units.day}`);
        }
        // Always show hours, minutes, and seconds for a better countdown experience
        parts.push(`${String(h).padStart(2, '0')}${units.hr}`);
        parts.push(`${String(m).padStart(2, '0')}${units.min}`);
        parts.push(`${String(s).padStart(2, '0')}${units.sec}`);
        
        timerElement.textContent = parts.join(' ');
    }

    function handleExpiry() {
        switch (onExpireAction) {
            case 'reload':
                location.reload();
                break;
            case 'message':
                container.querySelector('.countdown-wrapper').innerHTML = `<span class="badge badge-secondary">${expiredText}</span>`;
                break;
            case 'hide':
            default:
                container.style.display = 'none';
                break;
        }
    }

    const interval = setInterval(updateTimer, 1000);
    // Add the new interval ID to our global array for tracking.
    productCountdownIntervals.push(interval);
    updateTimer(); // Initial call to display the timer immediately
  });
}

// --- Event Listeners ---

// 1. Run the initializer on the initial page load.
document.addEventListener('DOMContentLoaded', () => {
    initializeProductCountdowns();
});

// 2. Run the initializer whenever PrestaShop updates the product block via AJAX.
// The `prestashop` object is globally available in modern themes.
if (typeof prestashop !== 'undefined') {
    prestashop.on('updateProduct', (data) => {
        // We use a small timeout to ensure the DOM has been fully updated by PrestaShop's scripts
        // before our script runs and looks for the new container. 100ms is usually safe.
        setTimeout(() => {
            initializeProductCountdowns();
        }, 100);
    });
}