react-date-picker/src/TimeInput/toTimeValue.js

A carefully crafted date picker for React

import leftPad from '../utils/leftPad'

export default ({ value, separator = ':', meridiem }) => {
  const parts = value.split(separator)

  const hours = parts[0]
  const minutes = parts[1]
  const seconds = parts[2]

  const result = { hours, minutes }

  if (typeof seconds == 'string' && seconds.length) {
    result.seconds = seconds
  }

  if (meridiem && seconds !== undefined && seconds * 1 != seconds) {
    result.seconds = leftPad(parseInt(seconds, 10))
  }

  if (meridiem && seconds === undefined && minutes * 1 != minutes) {
    result.minutes = leftPad(parseInt(minutes, 10))
  }

  if (meridiem) {
    const meridiems = ['am', 'AM', 'pm', 'PM']
    const indexes = meridiems.map(m => (seconds || minutes).indexOf(m))

    indexes.forEach((indexOf, i) => {
      if (indexOf != -1) {
        result.meridiem = meridiems[i]
      }
    })
  }

  return result
}