reservation.js

const { Data } = require("dataclass");

class Timespan extends Data {
  start;
  end;
}

open = [
  Timespan.create({
    start: new Date("December 12, 2022 11:00:00"),
    end: new Date("December 12, 2022 22:00:00"),
  }),
];

reservations = [
  Timespan.create({
    start: new Date("December 12, 2022 12:00:00"),
    end: new Date("December 12, 2022 12:30:00"),
  }),
];

bufferTime = 5;

function book(open, bufferTime, reservations, newReservation) {
  function addBuffer(date, bufferMinutes) {
    return new Date(date.getTime() + bufferMinutes * 60000);
  }
  // check if in service hours
  if (
    open.some(
      (slot) =>
        slot.start <= newReservation.start && slot.end >= newReservation.end
    )
  ) {
    console.log("in service hours");

    // check if there is a reservation that overlaps with the new reservation
    if (
      reservations.some(
        (existingReservation) =>
          (existingReservation.start <= newReservation.start &&
            addBuffer(existingReservation.end, bufferTime) >=
              newReservation.start) ||
          (existingReservation.start <= newReservation.end &&
            addBuffer(existingReservation.end, bufferTime) >=
              newReservation.end)
      )
    ) {
      console.log("overlapping reservation");
      return false;
    } else {
      console.log("no overlapping reservation");
      reservations.push(newReservation);
      return true;
    }
  } else {
    console.log("not in service hours");
    return false;
  }
}

newReservation = Timespan.create({
  start: new Date("December 12, 2022 12:15:00"),
  end: new Date("December 12, 2022 12:35:00"),
});
console.log(
  "Should be false: " + book(open, bufferTime, reservations, newReservation)
);
newReservation = Timespan.create({
  start: new Date("December 12, 2022 11:00:00"),
  end: new Date("December 12, 2022 11:30:00"),
});
console.log(
  "Should be true: " + book(open, bufferTime, reservations, newReservation)
);