import { hasMessageText, stripEmptyTextCharacters } from '../message_text'

const EMPTY = '\uFFFC'

describe('stripEmptyTextCharacters', () => {
  it.each([
    ['leaves ordinary text alone', 'Come on over after.', 'Come on over after.'],
    [
      'removes a trailing pair',
      `Yes. Come on over after.${EMPTY}${EMPTY}`,
      'Yes. Come on over after.',
    ],
    ['removes one mid-string', `before${EMPTY}after`, 'beforeafter'],
    ['reduces an all-empty body to an empty string', EMPTY, ''],
    ['reduces a repeated all-empty body to an empty string', `${EMPTY}${EMPTY}${EMPTY}`, ''],
    ['leaves an empty string alone', '', ''],
  ])('%s', (_name, input, expected) => {
    expect(stripEmptyTextCharacters(input)).toBe(expected)
  })

  it('does not disturb emoji or other multi-byte text', () => {
    expect(stripEmptyTextCharacters(`👋 hi${EMPTY}`)).toBe('👋 hi')
  })
})

describe('hasMessageText', () => {
  it.each([
    ['ordinary text', 'hello', true],
    ['text alongside an empty character', `hello${EMPTY}`, true],
    ['only an empty character', EMPTY, false],
    ['several empty characters', `${EMPTY}${EMPTY}`, false],
    ['an empty character surrounded by whitespace', `  ${EMPTY} `, false],
    ['whitespace only', '   ', false],
    ['empty string', '', false],
    ['undefined', undefined, false],
    ['null', null, false],
  ])('%s -> %s', (_name, input, expected) => {
    expect(hasMessageText(input)).toBe(expected)
  })

  it('is not fooled by trim alone, which does not treat the character as whitespace', () => {
    expect(EMPTY.trim()).toBe(EMPTY)
    expect(hasMessageText(EMPTY)).toBe(false)
  })
})