export function diffString(diff) {
  return diff < 0 ? `${diff}` : `+${diff}`
}

export default function calculateDiff(program, minutes, seconds, calories) {
  const {warmupMin, warmupCpm, cpm} = program;

  let preWarmup = 0;
  if (warmupMin > 0) {
    // Pre-warmup
    const warmedUpMinutes = Math.min(minutes, warmupMin);
    const warmedUpSeconds = minutes >= warmupMin ? 0 : seconds;
    preWarmup = Math.round((warmupCpm * (warmedUpMinutes + (warmedUpSeconds / 60))));
  }

  // Post-warmup
  const trainedMinutes = Math.max(0, minutes - warmupMin);
  const trainedSeconds = minutes >= warmupMin ? seconds : 0;
  const postWarmup = Math.round((cpm * (trainedMinutes + (trainedSeconds / 60))));

  // Sum
  const target = Math.round(preWarmup + postWarmup);

  return calories - target;
}