function likeButton(button) {
  const pressedClass = "like-button_pressed";
  let pressed = button.classList.contains(pressedClass);

  function press() {
    pressed = true;
    button.classList.add(pressedClass);
    button.setAttribute("aria-pressed", "true");
  }

  function unpress() {
    pressed = false;
    button.classList.remove(pressedClass);
    button.setAttribute("aria-pressed", "false");
  }

  button.addEventListener("click", function(e) {
    pressed ? unpress() : press();
  });
}

Array.prototype.slice
  .call(document.querySelectorAll(".like-button"))
  .forEach(likeButton);