// Only change code below this line
function updateRecords(id, prop, value) {
  //check that id exists in collection
  if (collection[id] === undefined) {
    console.log(`id: ${id} is not in collection`);
    return collection;
  }

  let obj = collection[id];

  if (value == "") {
    delete collection[id][prop];
    return collection;
  }

  switch (true) {
    case prop === "tracks":
      obj[prop] = obj[prop] || [];
      obj[prop].push(value);
      break;
    case prop != "tracks":
      obj[prop] = value;
      break;
  }

  collection[id] = obj;
  return collection;
}