Updates galore. Improved folder structure, componentized, and notifications upon completion.

static/js/modules/utils.js

@@ -0,0 +1,45 @@
+/**
+ * utils.js
+ * --------
+ * Pure utility functions with no DOM or state dependencies.
+ * Safe to import anywhere without side-effects.
+ */
+
+/**
+ * Escape a string for safe insertion into HTML.
+ * @param {*} str
+ * @returns {string}
+ */
+export function esc(str) {
+  if (!str) return '';
+  return String(str)
+    .replace(/&/g, '&')
+    .replace(/</g,  '&lt;')
+    .replace(/>/g,  '&gt;')
+    .replace(/"/g,  '&quot;')
+    .replace(/'/g,  '&#39;');
+}
+
+/**
+ * Format a duration in seconds as M:SS or H:MM:SS.
+ * @param {number} seconds
+ * @returns {string}
+ */
+export function fmtTime(seconds) {
+  const s   = Math.floor(seconds);
+  const h   = Math.floor(s / 3600);
+  const m   = Math.floor((s % 3600) / 60);
+  const sec = s % 60;
+  return h > 0
+    ? `${h}:${pad(m)}:${pad(sec)}`
+    : `${m}:${pad(sec)}`;
+}
+
+/**
+ * Zero-pad a number to at least 2 digits.
+ * @param {number} n
+ * @returns {string}
+ */
+export function pad(n) {
+  return String(n).padStart(2, '0');
+}