update: add calendar to app

src/lib/calendarDates.js

@@ -0,0 +1,30 @@
+// Truncates to minute precision so repeated ingests of "the same" slot land
+// on the same instant even though n8n's timestamps carry sub-minute noise
+// that differs run to run (the DB's UNIQUE(lower, upper) constraint depends
+// on this). Returns a Date (not a string) — pg accepts Date directly for a
+// timestamptz column.
+function normalizeISO(iso) {
+  const d = new Date(iso);
+  d.setSeconds(0, 0);
+  return d;
+}
+
+// Calendar date (YYYY-MM-DD) of the given instant in Europe/Paris, so e.g. a
+// 18:30 CEST slot stays on the correct local day regardless of what UTC day
+// it falls on.
+function slotDateParis(iso) {
+  return new Date(iso).toLocaleDateString('en-CA', { timeZone: 'Europe/Paris' });
+}
+
+const WEEKDAY_TO_NUMBER = { Mon: 1, Tue: 2, Wed: 3, Thu: 4, Fri: 5, Sat: 6, Sun: 7 };
+
+// Monday=1..Sunday=7, from the Europe/Paris-local weekday name. Falls back
+// to the instant's own (UTC) getDay() if the locale parsing ever fails.
+function dayOfWeekParis(iso) {
+  const date = new Date(iso);
+  const short = date.toLocaleDateString('en-US', { timeZone: 'Europe/Paris', weekday: 'short' }).slice(0, 3);
+  const dow = WEEKDAY_TO_NUMBER[short];
+  return dow === undefined ? date.getDay() || 7 : dow;
+}
+
+module.exports = { normalizeISO, slotDateParis, dayOfWeekParis };

src/lib/calendarWebhookAuth.js

@@ -0,0 +1,23 @@
+const crypto = require('crypto');
+const config = require('../config');
+
+// Protects the two endpoints n8n calls directly (server-to-server, no
+// browser session available) — a shared secret header instead of the
+// session-based auth the rest of /api uses. Constant-time compare since
+// this is a bearer-secret check.
+function calendarWebhookAuth(req, res, next) {
+  const provided = req.header('X-Calendar-Webhook-Secret') || '';
+  const expected = config.calendarWebhookSecret;
+
+  const providedBuf = Buffer.from(provided);
+  const expectedBuf = Buffer.from(expected);
+  const valid =
+    providedBuf.length === expectedBuf.length && crypto.timingSafeEqual(providedBuf, expectedBuf);
+
+  if (!valid) {
+    return res.status(401).json({ error: 'invalid_webhook_secret' });
+  }
+  next();
+}
+
+module.exports = calendarWebhookAuth;

src/lib/calendarWorkflowState.js

@@ -0,0 +1,25 @@
+// In-memory only — resets on process restart, which is fine: it just tracks
+// whether the last "refresh availability" run is idle/running/done/failed,
+// not data that needs to survive a restart. Shared between the session-gated
+// routes (src/routes/calendar.js) and the n8n-facing webhook routes
+// (src/routes/calendarWebhooks.js) so both can read/update the same state
+// without a require cycle between those two route files.
+let state = { status: 'idle', triggeredAt: null, message: null, node: null };
+
+function getState() {
+  return state;
+}
+
+function setRunning() {
+  state = { status: 'running', triggeredAt: new Date().toISOString(), message: null, node: null };
+}
+
+function setSuccess() {
+  state = { ...state, status: 'success', message: null, node: null };
+}
+
+function setError(message, node) {
+  state = { ...state, status: 'error', message: message || 'Unknown error', node: node || null };
+}
+
+module.exports = { getState, setRunning, setSuccess, setError };