/**
 * utils.js — Shared Utility Functions
 * 
 * XSS defense and common helpers.
 */

/**
 * Escape HTML special characters to prevent XSS when using innerHTML.
 * @param {*} str - Value to escape (null/undefined → empty string)
 * @returns {string} HTML-safe string
 */
export function escapeHtml(str) {
    if (str == null) return '';
    return String(str)
        .replace(/&/g, '&')
        .replace(/</g, '&lt;')
        .replace(/>/g, '&gt;')
        .replace(/"/g, '&quot;')
        .replace(/'/g, '&#39;');
}