Update Event Instance

//native

/**

 * Update Event Instance

 * Change one occurrence of a recurring event without touching the rest of the series (get instance ids from List Event Instances). Works on any event id; only the fields you set change. `start`/`end` take `YYYY-MM-DD` for all-day or RFC 3339 (`2026-10-05T10:00:00+02:00`); `time_zone` (IANA, e.g. Europe/Paris) applies to both. `attendees` replaces the guest list.

 */

export async function main(

  auth: RT.Gcal,

  event_id: string,

  calendar_id: string = "primary",

  summary: string | undefined,

  description: string | undefined,

  location: string | undefined,

  start: string | undefined,

  end: string | undefined,

  time_zone: string | undefined,

  attendees: string[] | undefined,

  send_updates: "all" | "externalOnly" | "none" = "all"

) {

  const when = (v: string) =>

    /^\d{4}-\d{2}-\d{2}$/.test(v)

      ? { date: v, dateTime: null }

      : { dateTime: v, date: null, timeZone: time_zone || undefined }

  const body: { [key: string]: any } = {

    summary: summary || undefined,

    description: description || undefined,

    location: location || undefined,

    start: start ? when(start) : undefined,

    end: end ? when(end) : undefined,

    attendees: attendees?.length

      ? attendees.map((email) => ({ email }))

      : undefined,

  }

  const response = await fetch(

    `https://www.googleapis.com/calendar/v3/calendars/${encodeURIComponent(calendar_id || "primary")}/events/${event_id}?sendUpdates=${send_updates || "all"}`,

    {

      method: "PATCH",

      headers: {

        Authorization: `Bearer ${auth.token}`,

        "Content-Type": "application/json",

        Accept: "application/json",

      },

      body: JSON.stringify(body),

    }

  )

  if (!response.ok) {

    throw new Error(`${response.status} ${await response.text()}`)

  }

  return await response.json()

}