Create `generateIcsString` function

packages/emails/lib/generateIcsString.ts

@@ -0,0 +1,81 @@
+import type { DateArray } from "ics";
+import { createEvent } from "ics";
+import { RRule } from "rrule";
+
+import dayjs from "@calcom/dayjs";
+import { getRichDescription } from "@calcom/lib/CalEventParser";
+import type { CalendarEvent, Person } from "@calcom/types/Calendar";
+
+const generateIcsString = ({
+  event,
+  recipient,
+  role,
+}: {
+  event: CalendarEvent;
+  recipient: Person;
+  role: "attendee" | "organizer";
+}) => {
+  const t = recipient.language.translate;
+  // Taking care of recurrence rule
+  let recurrenceRule: string | undefined = undefined;
+  if (event.recurringEvent?.count) {
+    // ics appends "RRULE:" already, so removing it from RRule generated string
+    recurrenceRule = new RRule(event.recurringEvent).toString().replace("RRULE:", "");
+  }
+
+  const getTextBody = (title = "", subtitle = "emailed_you_and_any_other_attendees"): string => {
+    if (!title) {
+      if (role === "organizer") {
+        title = event.recurringEvent?.count ? "new_event_scheduled_recurring" : "new_event_scheduled";
+      }
+      if (role === "attendee") {
+        title = event.recurringEvent?.count
+          ? "your_event_has_been_scheduled_recurring"
+          : "your_event_has_been_scheduled";
+      }
+    }
+
+    return `
+${t(title)}
+${t(subtitle)}
+
+${getRichDescription(event, t)}
+`.trim();
+  };
+
+  const icsEvent = createEvent({
+    uid: event.iCalUID || event.uid!,
+    sequence: event.iCalSequence || 0,
+    start: dayjs(event.startTime)
+      .utc()
+      .toArray()
+      .slice(0, 6)
+      .map((v, i) => (i === 1 ? v + 1 : v)) as DateArray,
+    startInputType: "utc",
+    productId: "calcom/ics",
+    title: event.title,
+    description: getTextBody(),
+    duration: { minutes: dayjs(event.endTime).diff(dayjs(event.startTime), "minute") },
+    organizer: { name: event.organizer.name, email: event.organizer.email },
+    ...{ recurrenceRule },
+    attendees: [
+      ...event.attendees.map((attendee: Person) => ({
+        name: attendee.name,
+        email: attendee.email,
+      })),
+      ...(event.team?.members
+        ? event.team?.members.map((member: Person) => ({
+            name: member.name,
+            email: member.email,
+          }))
+        : []),
+    ],
+    status: "CONFIRMED",
+  });
+  if (icsEvent.error) {
+    throw icsEvent.error;
+  }
+  return icsEvent.value;
+};
+
+export default generateIcsString;