Rearrange VALARM segment to be after RRULE and DURATION

iCalendarUtils.test.ts

import { rearrangeCalendarStringsForOutlook } from "../iCalendarUtils";

describe("rearrangeCalendarStringsForOutlook()", () => {
  test("should handle a single resort", () => {
    const singleBefore = dedent`
      BEGIN:VCALENDAR
      VERSION:2.0
      CALSCALE:GREGORIAN
      PRODID:TiE23/ical
      START:VEVENT
      BEGIN:VALARM
      ACTION:DISPLAY
      TRIGGER:-PT10M
      END:VALARM
      RRULE:FREQ=WEEKLY;BYDAY=MO;UNTIL=20301224T235900Z
      DURATION:PT45M
      END:VEVENT
      END:VCALENDAR
    `;
    const singleAfter = dedent`
      BEGIN:VCALENDAR
      VERSION:2.0
      CALSCALE:GREGORIAN
      PRODID:TiE23/ical
      START:VEVENT
      RRULE:FREQ=WEEKLY;BYDAY=MO;UNTIL=20301224T235900Z
      DURATION:PT45M
      BEGIN:VALARM
      ACTION:DISPLAY
      TRIGGER:-PT10M
      END:VALARM
      END:VEVENT
      END:VCALENDAR
    `;

    expect(rearrangeCalendarStringsForOutlook(singleBefore)).toEqual(
      singleAfter
    );
  });
  test("it should handle two resorts", () => {
    const multiBefore = dedent`
      BEGIN:VCALENDAR
      VERSION:2.0
      CALSCALE:GREGORIAN
      PRODID:TiE23/ical
      START:VEVENT
      SUMMARY: Blah blah
      BEGIN:VALARM
      ACTION:DISPLAY
      TRIGGER:-PT10M
      END:VALARM
      RRULE:FREQ=WEEKLY;BYDAY=MO;UNTIL=20301224T235900Z
      DURATION:PT45M
      END:VEVENT
      START:VEVENT
      SUMMARY: Blah blah
      BEGIN:VALARM
      ACTION:DISPLAY
      TRIGGER:-PT10M
      END:VALARM
      RRULE:FREQ=WEEKLY;BYDAY=MO;UNTIL=20301224T235900Z
      DURATION:PT45M
      END:VEVENT
      END:VCALENDAR
    `;
    const multiAfter = dedent`
      BEGIN:VCALENDAR
      VERSION:2.0
      CALSCALE:GREGORIAN
      PRODID:TiE23/ical
      START:VEVENT
      SUMMARY: Blah blah
      RRULE:FREQ=WEEKLY;BYDAY=MO;UNTIL=20301224T235900Z
      DURATION:PT45M
      BEGIN:VALARM
      ACTION:DISPLAY
      TRIGGER:-PT10M
      END:VALARM
      END:VEVENT
      START:VEVENT
      SUMMARY: Blah blah
      RRULE:FREQ=WEEKLY;BYDAY=MO;UNTIL=20301224T235900Z
      DURATION:PT45M
      BEGIN:VALARM
      ACTION:DISPLAY
      TRIGGER:-PT10M
      END:VALARM
      END:VEVENT
      END:VCALENDAR
    `;

    expect(rearrangeCalendarStringsForOutlook(multiBefore)).toEqual(
      multiAfter
    );
  });

  test("it should work if there is no RRULE line", () => {
    const singleBeforeNoRRULE = dedent`
      BEGIN:VCALENDAR
      VERSION:2.0
      CALSCALE:GREGORIAN
      PRODID:TiE23/ical
      START:VEVENT
      SUMMARY: Blah blah
      BEGIN:VALARM
      ACTION:DISPLAY
      TRIGGER:-PT10M
      END:VALARM
      DURATION:PT45M
      END:VEVENT
      END:VCALENDAR
    `;
    const singleAfterNoRRULE = dedent`
      BEGIN:VCALENDAR
      VERSION:2.0
      CALSCALE:GREGORIAN
      PRODID:TiE23/ical
      START:VEVENT
      SUMMARY: Blah blah
      DURATION:PT45M
      BEGIN:VALARM
      ACTION:DISPLAY
      TRIGGER:-PT10M
      END:VALARM
      END:VEVENT
      END:VCALENDAR
    `;

    expect(rearrangeCalendarStringsForOutlook(singleBeforeNoRRULE)).toEqual(
      singleAfterNoRRULE
    );
  });

  test("it should work if there is no DURATION line", () => {
    const singleBeforeNoDURATION = dedent`
      BEGIN:VCALENDAR
      VERSION:2.0
      CALSCALE:GREGORIAN
      PRODID:TiE23/ical
      START:VEVENT
      SUMMARY: Blah blah
      BEGIN:VALARM
      ACTION:DISPLAY
      TRIGGER:-PT10M
      END:VALARM
      RRULE:FREQ=WEEKLY;BYDAY=MO;UNTIL=20301224T235900Z
      END:VEVENT
      END:VCALENDAR
    `;
    const singleAfterNoDURATION = dedent`
      BEGIN:VCALENDAR
      VERSION:2.0
      CALSCALE:GREGORIAN
      PRODID:TiE23/ical
      START:VEVENT
      SUMMARY: Blah blah
      RRULE:FREQ=WEEKLY;BYDAY=MO;UNTIL=20301224T235900Z
      BEGIN:VALARM
      ACTION:DISPLAY
      TRIGGER:-PT10M
      END:VALARM
      END:VEVENT
      END:VCALENDAR
    `;

    expect(
      rearrangeCalendarStringsForOutlook(singleBeforeNoDURATION)
    ).toEqual(singleAfterNoDURATION);
  });

  test("it should work if there is no DURATION line", () => {
    const singleBeforeNoRRULENoDURATION = dedent`
      BEGIN:VCALENDAR
      VERSION:2.0
      CALSCALE:GREGORIAN
      PRODID:TiE23/ical
      START:VEVENT
      SUMMARY: Blah blah
      BEGIN:VALARM
      ACTION:DISPLAY
      TRIGGER:-PT10M
      END:VALARM
      END:VEVENT
      END:VCALENDAR
    `;
    const singleAfterNoRRULENoDURATION = dedent`
      BEGIN:VCALENDAR
      VERSION:2.0
      CALSCALE:GREGORIAN
      PRODID:TiE23/ical
      START:VEVENT
      SUMMARY: Blah blah
      BEGIN:VALARM
      ACTION:DISPLAY
      TRIGGER:-PT10M
      END:VALARM
      END:VEVENT
      END:VCALENDAR
    `;

    expect(
      rearrangeCalendarStringsForOutlook(singleBeforeNoRRULENoDURATION)
    ).toEqual(singleAfterNoRRULENoDURATION);
  });

  test("it should work if there is no ALARMS", () => {
    const singleBeforeNoVALARM = dedent`
      BEGIN:VCALENDAR
      VERSION:2.0
      CALSCALE:GREGORIAN
      PRODID:TiE23/ical
      START:VEVENT
      RRULE:FREQ=WEEKLY;BYDAY=MO;UNTIL=20301224T235900Z
      DURATION:PT45M
      END:VEVENT
      END:VCALENDAR
    `;
    const singleAfterNoVALARM = dedent`
      BEGIN:VCALENDAR
      VERSION:2.0
      CALSCALE:GREGORIAN
      PRODID:TiE23/ical
      START:VEVENT
      RRULE:FREQ=WEEKLY;BYDAY=MO;UNTIL=20301224T235900Z
      DURATION:PT45M
      END:VEVENT
      END:VCALENDAR
    `;

    expect(rearrangeCalendarStringsForOutlook(singleBeforeNoVALARM)).toEqual(
      singleAfterNoVALARM
    );
  });

  test("it should work if there is nothing in the string", () => {
    expect(rearrangeCalendarStringsForOutlook("")).toEqual("");
  });
});

iCalendarUtils.ts

export function rearrangeCalendarStringsForOutlook(iCal: string): string {
  return iCal.replace(
    /(^BEGIN:VALARM(.|\r?\n)*?END:VALARM$\r?\n)(.|\r?\n)*?(^RRULE:.*$\r?\n)?(.|\r?\n)*?(^DURATION:.*$\r?\n)?(.|\r?\n)*?/gm,
    "$4$6$1"
  );
}

Oh, must mention that yes, there is one module I'm using in the unit test: dedent. deline (by AirBnB) does the same exact thing.