Close pre-sale registration a configurable time before events start.

Events gain nullable presale_closure_enabled / presale_close_minutes_before
overrides; null inherits the new site_settings defaults (enabled, 120 min).
A shared resolver computes the effective cutoff, which the public event API
exposes as presaleClosesAt and the public booking endpoint enforces. Door and
admin ticket creation are not gated.

Admin: toggle + duration picker in the event modal (pre-filled from the site
default) and a matching default card on Settings › General. Public: the event
page shows "Registration Closed" after the cutoff and the checkout page
redirects back.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

backend/src/lib/presale.test.ts

@@ -0,0 +1,75 @@
+import { describe, it, expect } from 'vitest';
+import {
+  resolvePresaleClosure,
+  isPresaleClosed,
+  DEFAULT_PRESALE_CLOSE_MINUTES,
+} from './presale.js';
+
+const START = '2030-01-01T20:00:00.000Z';
+const startMs = new Date(START).getTime();
+const minutes = (n: number) => n * 60_000;
+
+describe('resolvePresaleClosure', () => {
+  it('falls back to the built-in defaults when neither event nor settings specify anything', () => {
+    const r = resolvePresaleClosure({ startDatetime: START }, null);
+    expect(r.enabled).toBe(true);
+    expect(r.minutesBefore).toBe(DEFAULT_PRESALE_CLOSE_MINUTES);
+    expect(r.closesAt?.getTime()).toBe(startMs - minutes(DEFAULT_PRESALE_CLOSE_MINUTES));
+  });
+
+  it('inherits from site settings when the event has null overrides', () => {
+    const r = resolvePresaleClosure(
+      { startDatetime: START, presaleClosureEnabled: null, presaleCloseMinutesBefore: null },
+      { presaleClosureEnabled: true, presaleCloseMinutesBefore: 30 }
+    );
+    expect(r.minutesBefore).toBe(30);
+    expect(r.closesAt?.getTime()).toBe(startMs - minutes(30));
+  });
+
+  it('lets the event override the site settings', () => {
+    const r = resolvePresaleClosure(
+      { startDatetime: START, presaleClosureEnabled: true, presaleCloseMinutesBefore: 1440 },
+      { presaleClosureEnabled: false, presaleCloseMinutesBefore: 30 }
+    );
+    expect(r.enabled).toBe(true);
+    expect(r.closesAt?.getTime()).toBe(startMs - minutes(1440));
+  });
+
+  it('returns closesAt null when closure is disabled (site-wide or per event)', () => {
+    expect(resolvePresaleClosure({ startDatetime: START }, { presaleClosureEnabled: false }).closesAt).toBeNull();
+    expect(
+      resolvePresaleClosure({ startDatetime: START, presaleClosureEnabled: false }, { presaleClosureEnabled: true }).closesAt
+    ).toBeNull();
+  });
+
+  it('accepts PostgreSQL 0/1 integers and string minutes', () => {
+    const r = resolvePresaleClosure(
+      { startDatetime: new Date(START), presaleClosureEnabled: 1, presaleCloseMinutesBefore: '45' },
+      { presaleClosureEnabled: 0, presaleCloseMinutesBefore: 10 }
+    );
+    expect(r.enabled).toBe(true);
+    expect(r.minutesBefore).toBe(45);
+    const off = resolvePresaleClosure({ startDatetime: START, presaleClosureEnabled: 0 }, { presaleClosureEnabled: 1 });
+    expect(off.enabled).toBe(false);
+  });
+
+  it('closes at the event start when minutes is 0', () => {
+    const r = resolvePresaleClosure({ startDatetime: START, presaleCloseMinutesBefore: 0 }, null);
+    expect(r.closesAt?.getTime()).toBe(startMs);
+  });
+});
+
+describe('isPresaleClosed', () => {
+  const event = { startDatetime: START, presaleClosureEnabled: true, presaleCloseMinutesBefore: 60 };
+
+  it('is open before the cutoff and closed from the cutoff onwards', () => {
+    const cutoff = startMs - minutes(60);
+    expect(isPresaleClosed(event, null, cutoff - 1)).toBe(false);
+    expect(isPresaleClosed(event, null, cutoff)).toBe(true);
+    expect(isPresaleClosed(event, null, startMs + minutes(5))).toBe(true);
+  });
+
+  it('never closes when closure is disabled', () => {
+    expect(isPresaleClosed({ ...event, presaleClosureEnabled: false }, null, startMs + minutes(60))).toBe(false);
+  });
+});

backend/src/lib/presale.ts

@@ -0,0 +1,70 @@
+/**
+ * Pre-sale closure: online registration for an event closes a configurable
+ * number of minutes before the event starts.
+ *
+ * Each event may override the site-wide default; a `null`/`undefined` value on
+ * the event means "inherit from site_settings". Values arrive as booleans on
+ * SQLite and as 0/1 integers on PostgreSQL, so both are accepted here.
+ */
+
+export const DEFAULT_PRESALE_CLOSURE_ENABLED = true;
+export const DEFAULT_PRESALE_CLOSE_MINUTES = 120;
+
+export interface PresaleEventLike {
+  startDatetime: string | Date;
+  presaleClosureEnabled?: boolean | number | null;
+  presaleCloseMinutesBefore?: number | string | null;
+}
+
+export interface PresaleSettingsLike {
+  presaleClosureEnabled?: boolean | number | null;
+  presaleCloseMinutesBefore?: number | string | null;
+}
+
+export interface ResolvedPresaleClosure {
+  enabled: boolean;
+  minutesBefore: number;
+  /** When online registration closes, or null when closure is disabled. */
+  closesAt: Date | null;
+}
+
+function toBool(value: boolean | number | null | undefined): boolean | null {
+  if (value === null || value === undefined) return null;
+  return typeof value === 'number' ? value !== 0 : Boolean(value);
+}
+
+function toMinutes(value: number | string | null | undefined): number | null {
+  if (value === null || value === undefined) return null;
+  const n = typeof value === 'string' ? parseInt(value, 10) : value;
+  return Number.isFinite(n) && n >= 0 ? Math.floor(n) : null;
+}
+
+export function resolvePresaleClosure(
+  event: PresaleEventLike,
+  settings?: PresaleSettingsLike | null
+): ResolvedPresaleClosure {
+  const enabled =
+    toBool(event.presaleClosureEnabled) ??
+    toBool(settings?.presaleClosureEnabled) ??
+    DEFAULT_PRESALE_CLOSURE_ENABLED;
+  const minutesBefore =
+    toMinutes(event.presaleCloseMinutesBefore) ??
+    toMinutes(settings?.presaleCloseMinutesBefore) ??
+    DEFAULT_PRESALE_CLOSE_MINUTES;
+
+  if (!enabled) return { enabled, minutesBefore, closesAt: null };
+
+  const startMs = new Date(event.startDatetime).getTime();
+  if (!Number.isFinite(startMs)) return { enabled, minutesBefore, closesAt: null };
+
+  return { enabled, minutesBefore, closesAt: new Date(startMs - minutesBefore * 60_000) };
+}
+
+export function isPresaleClosed(
+  event: PresaleEventLike,
+  settings?: PresaleSettingsLike | null,
+  nowMs: number = Date.now()
+): boolean {
+  const { closesAt } = resolvePresaleClosure(event, settings);
+  return closesAt !== null && closesAt.getTime() <= nowMs;
+}