import prisma from "@lib/prisma";
import { deleteEvent } from "@lib/calendarClient";
import async from "async";
import { deleteMeeting } from "@lib/videoClient";
import { asStringOrNull } from "@lib/asStringOrNull";
import { BookingStatus } from "@prisma/client";

export default async function handler(req, res) {
  if (req.method == "POST") {
    const uid = asStringOrNull(req.body.uid);

    const bookingToDelete = await prisma.booking.findUnique({
      where: {
        uid,
      },
      select: {
        id: true,
        user: {
          select: {
            credentials: true,
          },
        },
        attendees: true,
        references: {
          select: {
            uid: true,
            type: true,
          },
        },
      },
    });

    if (!bookingToDelete) {
      return res.status(404).end();
    }

    // by cancelling first, and blocking whilst doing so; we can ensure a cancel
    // action always succeeds even if subsequent integrations fail cancellation.
    await prisma.booking.update({
      where: {
        uid,
      },
      data: {
        status: BookingStatus.CANCELLED,
      },
    });

    const apiDeletes = async.mapLimit(bookingToDelete.user.credentials, 5, async (credential) => {
      const bookingRefUid = bookingToDelete.references.filter((ref) => ref.type === credential.type)[0]?.uid;
      if (bookingRefUid) {
        if (credential.type.endsWith("_calendar")) {
          return await deleteEvent(credential, bookingRefUid);
        } else if (credential.type.endsWith("_video")) {
          return await deleteMeeting(credential, bookingRefUid);
        }
      }
    });

    const attendeeDeletes = prisma.attendee.deleteMany({
      where: {
        bookingId: bookingToDelete.id,
      },
    });

    const bookingReferenceDeletes = prisma.bookingReference.deleteMany({
      where: {
        bookingId: bookingToDelete.id,
      },
    });

    await Promise.all([apiDeletes, attendeeDeletes, bookingReferenceDeletes]);

    //TODO Perhaps send emails to user and client to tell about the cancellation

    res.status(200).json({ message: "Booking successfully deleted." });
  } else {
    res.status(405).json({ message: "This endpoint only accepts POST requests." });
  }
}