Bongo Cat plays Baby Shark

bongo-cat-baby-shark.js

// https://bongo.cat/
// Copy and paste in the browser console.

const playNote = key => {
  const downEvent = new KeyboardEvent('keydown', { 'key': key } )
  const upEvent = new KeyboardEvent('keyup', { 'key': key } )
  document.dispatchEvent(downEvent);
  setTimeout(() => document.dispatchEvent(upEvent), 100);
}

const playSong = (score, tempo) =>
  score
    .reduce((acc, [note, length]) => {
      const time = acc + length * tempo;
      if(note !== '!')
        setTimeout(() => playNote(note), time)
      return time;
    }, 400)


const babyShark = [
  ["3", 1/2],
  ["5", 1/2],
  ["8", 1/4],
  ["8", 1/4],
  ["8", 1/4],
  ["8", 1/8],
  ["8", 1/4],
  ["8", 1/8],
  ["8", 1/4],

  ["3", 1/4],
  ["5", 1/4],
  ["8", 1/4],
  ["8", 1/4],
  ["8", 1/4],
  ["8", 1/8],
  ["8", 1/4],
  ["8", 1/8],
  ["8", 1/4],

  ["3", 1/4],
  ["5", 1/4],
  ["8", 1/4],
  ["8", 1/4],
  ["8", 1/4],
  ["8", 1/8],
  ["8", 1/4],
  ["8", 1/8],
  ["8", 1/4],

  ["8", 1/4],
  ["8", 1/4],
  ["7", 1/4],
  [" ", 1/4],
  ["!", 1/2],
]

playSong(
  babyShark
   .concat(babyShark)
   .concat(babyShark)
  , 800);