Autoscroller

autoscroll.js

(function (pixelsToScroll) {
  const byteFormatter = new Intl.NumberFormat(undefined, {
    style: "unit",
    unit: "megabyte",
    maximumFractionDigits: 0,
    minimumFractionDigits: 0,
  });
  const numberFormatter = new Intl.NumberFormat();
  const formatBytes = (bytes) => byteFormatter.format(bytes / (1024 * 1024));
  const formatPercentage = (dec) => `${Math.round(100 * dec)}%`;
  function stats() {
    const m = window.performance.memory;
    console.log(
      "Memory: %s used of %s (%s)",
      formatBytes(m.usedJSHeapSize),
      formatBytes(m.totalJSHeapSize),
      formatPercentage(m.usedJSHeapSize / m.totalJSHeapSize)
    );
    console.log(
      "Position: %s",
      numberFormatter.format(document.body.scrollHeight)
    );
    console.log(
      "Elements in timeline: %s",
      numberFormatter.format(document.getElementsByClassName("_1DxdS").length)
    );
  }

  function scrollToBottom() {
    window.scrollTo({ top: document.body.scrollHeight, behavior: "smooth" });
  }

  let nextTurn;
  function scrollPixels() {
    if (document.body.scrollHeight < pixelsToScroll) {
      scrollToBottom();
      stats();
      nextTurn = setTimeout(scrollPixels, 2000);
    } else {
      stats();
      console.log(
        "%s posts, %s ads in timeline",
        numberFormatter.format(
          document.querySelectorAll("._1DxdS._2jOH-").length
        ),
        numberFormatter.format(
          document.querySelectorAll("._1DxdS:not(._2jOH-)").length
        )
      );
    }
  }
  scrollPixels();

  window._stop = () => {
    console.log("stopping");
    clearInterval(nextTurn);
    stats();
    console.log(
      "Elements in timeline: %s",
      numberFormatter.format(document.getElementsByClassName("_1DxdS").length)
    );
  };
})(500000);