transferred-missed.js

const R = require('ramda');

const xs = [
  {
    agent: 'Kim', ring_time: 1, queue_id: 1, talk_time: 0,
  },
  {
    agent: 'Frank', ring_time: 1, queue_id: 1, talk_time: 0,
  },
  {
    agent: 'Kayla', ring_time: 1, queue_id: 1, talk_time: 1,
  },
  {
    agent: 'Jon', ring_time: 1, queue_id: 1, talk_time: 0,
  },
  {
    agent: 'Myke', ring_time: 0, queue_id: 1, talk_time: 0,
  },
  {
    agent: 'Dan', ring_time: 1, queue_id: 1, talk_time: 0,
  },
];

const getMissedTransferLegs = R.ifElse(
  R.find((o) => o.agent && o.talk_time > 0),
  R.pipe(
    R.takeLastWhile((o) => !(o.agent && o.talk_time > 0)),
    R.filter((o) => o.agent && o.ring_time > 0 && o.talk_time === 0),
  ),
  R.always([]),
);

console.log(getMissedTransferLegs(xs));