RRULE Patterns

// Every Monday
'FREQ=WEEKLY;BYDAY=MO'

// Every Tuesday and Thursday
'FREQ=WEEKLY;BYDAY=TU,TH'

// Monday, Wednesday, Friday
'FREQ=WEEKLY;BYDAY=MO,WE,FR'

// Every other Tuesday and Thursday
'FREQ=WEEKLY;INTERVAL=2;BYDAY=TU,TH'

// Every Monday until end of semester
'FREQ=WEEKLY;BYDAY=MO;UNTIL=20260731T235959Z'

// Daily for 14 weeks (weekdays only, 70 occurrences)
'FREQ=DAILY;COUNT=70;BYDAY=MO,TU,WE,TH,FR'

// 15 weekly sessions
'FREQ=WEEKLY;COUNT=15;BYDAY=WE'

// 2x per week, 15-week semester
const weeklyLecture = {
    title: 'CS 101 - Intro to Programming',
    startTime: new Date('2026-03-02T09:00:00'),  // Monday 9 AM
    durationMin: 90,
    recurrenceRule: 'FREQ=WEEKLY;BYDAY=MO,WE;UNTIL=20260619T235959Z',
};

// Weekly lab on Friday
const labSession = {
    title: 'CS 101 - Lab',
    startTime: new Date('2026-03-06T14:00:00'),  // Friday 2 PM
    durationMin: 120,
    recurrenceRule: 'FREQ=WEEKLY;BYDAY=FR;UNTIL=20260619T235959Z',
};

// First Wednesday of each month
'FREQ=MONTHLY;BYDAY=1WE'

// Last Friday of each month
'FREQ=MONTHLY;BYDAY=-1FR'

// One-time event (no RRULE)
const finalExam = {
    title: 'CS 101 - Final Exam',
    startTime: new Date('2026-06-22T09:00:00'),
    durationMin: 180,
    recurrenceRule: null,  // null = one-time event
};

// Cancel the March 30 occurrence (spring break)
await eventStorage.createException({
    eventId: lecture.id,
    originalDate: new Date('2026-03-30'),
    type: 'cancelled',
    newStartTime: null,
    newDurationMin: null,
    newRoomId: null,
    metadata: { reason: 'Spring Break' },
});

// Room change for April 6 occurrence
await eventStorage.createException({
    eventId: lecture.id,
    originalDate: new Date('2026-04-06'),
    type: 'modified',
    newStartTime: null,          // keep same time
    newDurationMin: null,        // keep same duration
    newRoomId: 'large-auditorium',  // different room
    metadata: { reason: 'Guest lecturer' },
});

// Extra session on Saturday to make up for cancelled class
await eventStorage.createException({
    eventId: lecture.id,
    originalDate: new Date('2026-04-04'),  // Saturday
    type: 'added',
    newStartTime: new Date('2026-04-04T10:00:00'),
    newDurationMin: 90,
    newRoomId: null,  // same room as parent event
    metadata: { reason: 'Makeup session' },
});

import { RecurrenceService } from '@hfu.digital/coursekit-nestjs';

const error = recurrence.validateRule('FREQ=WEEKLY;BYDAY=MO');
if (error !== null) {
    throw new Error(`Invalid RRULE: ${error}`);
}