feat(admission): add scheduled group access

2026-08-02 14:04:48 -04:00
parent eb1c5b6de4
commit c131465ff5
32 changed files with 2446 additions and 59 deletions
@@ -0,0 +1,119 @@
+export const MINUTES_PER_WEEK = 7 * 24 * 60;
+const MAX_WINDOWS = 50;
+
+export interface WeeklyAccessWindow {
+  startMinuteOfWeek: number;
+  endMinuteOfWeek: number;
+}
+
+interface ScheduleDecision {
+  allowed: boolean;
+  nextWindow: { start: Date; end: Date } | null;
+}
+
+function normalizedMinute(value: number) {
+  return ((value % MINUTES_PER_WEEK) + MINUTES_PER_WEEK) % MINUTES_PER_WEEK;
+}
+
+function validWindow(window: WeeklyAccessWindow) {
+  return Number.isInteger(window.startMinuteOfWeek)
+    && Number.isInteger(window.endMinuteOfWeek)
+    && window.startMinuteOfWeek >= 0
+    && window.startMinuteOfWeek < MINUTES_PER_WEEK
+    && window.endMinuteOfWeek >= 0
+    && window.endMinuteOfWeek < MINUTES_PER_WEEK
+    && window.startMinuteOfWeek !== window.endMinuteOfWeek;
+}
+
+function segments(window: WeeklyAccessWindow) {
+  return window.endMinuteOfWeek > window.startMinuteOfWeek
+    ? [[window.startMinuteOfWeek, window.endMinuteOfWeek] as const]
+    : [
+        [window.startMinuteOfWeek, MINUTES_PER_WEEK] as const,
+        [0, window.endMinuteOfWeek] as const,
+      ];
+}
+
+export function validateScheduleWindows(windows: WeeklyAccessWindow[]) {
+  if (windows.length > MAX_WINDOWS || windows.some((window) => !validWindow(window))) return null;
+  for (let left = 0; left < windows.length; left += 1) {
+    for (let right = left + 1; right < windows.length; right += 1) {
+      const overlaps = segments(windows[left]!).some(([leftStart, leftEnd]) =>
+        segments(windows[right]!).some(([rightStart, rightEnd]) =>
+          leftStart < rightEnd && rightStart < leftEnd));
+      if (overlaps) return null;
+    }
+  }
+  return [...windows].sort((left, right) => left.startMinuteOfWeek - right.startMinuteOfWeek);
+}
+
+export function parseScheduleWindows(formData: FormData) {
+  const starts = formData.getAll("startMinuteOfWeek").map(String);
+  const ends = formData.getAll("endMinuteOfWeek").map(String);
+  if (starts.length !== ends.length) return null;
+  const decimalInteger = /^(0|[1-9]\d*)$/;
+  if (starts.some((value) => !decimalInteger.test(value)) || ends.some((value) => !decimalInteger.test(value))) {
+    return null;
+  }
+  return validateScheduleWindows(starts.map((start, index) => ({
+    startMinuteOfWeek: Number(start),
+    endMinuteOfWeek: Number(ends[index]),
+  })));
+}
+
+function utcWeekStart(now: Date) {
+  const dayFromMonday = (now.getUTCDay() + 6) % 7;
+  return Date.UTC(now.getUTCFullYear(), now.getUTCMonth(), now.getUTCDate() - dayFromMonday);
+}
+
+function windowDuration(window: WeeklyAccessWindow) {
+  return normalizedMinute(window.endMinuteOfWeek - window.startMinuteOfWeek);
+}
+
+export function evaluateGroupSchedule(windows: WeeklyAccessWindow[], now: Date): ScheduleDecision {
+  if (!windows.length) return { allowed: true, nextWindow: null };
+  const valid = validateScheduleWindows(windows);
+  if (!valid || !Number.isFinite(now.getTime())) return { allowed: false, nextWindow: null };
+
+  const weekStart = utcWeekStart(now);
+  const occurrences = valid.flatMap((window) => [-1, 0, 1].map((weekOffset) => {
+    const start = new Date(weekStart + (weekOffset * MINUTES_PER_WEEK + window.startMinuteOfWeek) * 60_000);
+    const end = new Date(start.getTime() + windowDuration(window) * 60_000);
+    return { start, end };
+  }));
+  if (occurrences.some(({ start, end }) => now >= start && now < end)) {
+    return { allowed: true, nextWindow: null };
+  }
+  const nextWindow = occurrences
+    .filter(({ start }) => start > now)
+    .sort((left, right) => left.start.getTime() - right.start.getTime())[0] ?? null;
+  return { allowed: false, nextWindow };
+}
+
+export function localWindowToUtc(window: WeeklyAccessWindow, browserOffsetMinutes: number) {
+  return {
+    startMinuteOfWeek: normalizedMinute(window.startMinuteOfWeek + browserOffsetMinutes),
+    endMinuteOfWeek: normalizedMinute(window.endMinuteOfWeek + browserOffsetMinutes),
+  };
+}
+
+export function utcWindowToLocal(window: WeeklyAccessWindow, browserOffsetMinutes: number) {
+  return {
+    startMinuteOfWeek: normalizedMinute(window.startMinuteOfWeek - browserOffsetMinutes),
+    endMinuteOfWeek: normalizedMinute(window.endMinuteOfWeek - browserOffsetMinutes),
+  };
+}
+
+const WEEKDAYS = ["Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday"] as const;
+
+export function formatWeeklyMinute(minuteOfWeek: number) {
+  const minute = normalizedMinute(minuteOfWeek);
+  const day = WEEKDAYS[Math.floor(minute / (24 * 60))];
+  const hour = Math.floor((minute % (24 * 60)) / 60);
+  const minuteOfHour = minute % 60;
+  return `${day} ${String(hour).padStart(2, "0")}:${String(minuteOfHour).padStart(2, "0")}`;
+}
+
+export function formatScheduleInstant(value: Date) {
+  return `${value.toISOString().slice(0, 16).replace("T", " ")} UTC`;
+}