4chan-id-blocker.user.js

// ==UserScript==
// @name        4chan id blocker - 4chan.org
// @namespace   Violentmonkey Scripts
// @match       https://boards.4chan.org/*
// @grant       none
// @version     1.0
// @author      -
// @description -
// ==/UserScript==

var bannedIds = {};

function hideElement(node) {
  node.style.display = "none";
}

function removePostFromIdNode(node) {
  var postNode = node.parentNode.parentNode.parentNode;
  var prevNode = postNode.previousSibling;

  hideElement(postNode);
  hideElement(prevNode);
}

function makeHideHandler(posterId) {
  return function() {
    var elts = document.getElementsByTagName("span");

    for (var i = 0; i < elts.length; i++) {
      var elt = elts[i];

      if (elt.getAttribute("class") != "posteruid id_" + posterId)
        continue;

      removePostFromIdNode(elt);
    }

    bannedIds[posterId] = 1;
  };
}


function hideBannedIds() {
  var elts = document.getElementsByTagName("span");

  for (var i = 0; i < elts.length; i++) {
    var elt = elts[i];

    var cls = elt.getAttribute("class");

    if (!cls) continue;

    if (cls.substring(0, 13) != "posteruid id_") continue;

    var posterId = cls.substring(13);

    if (bannedIds[posterId] == 1) {
      removePostFromIdNode(elt);
    }
  }
}


function addHideButtons() {
  var elts = document.getElementsByTagName("span");

  for (var i = 0; i < elts.length; i++) {
    var elt = elts[i];

    if (elt.getAttribute("class") != "hand" ||
        elt.getAttribute("title") != "Highlight posts by this ID" ||
        elt.getAttribute("data-has-block-button") == "true")
      continue;

    var xNode = document.createElement("span");
    xNode.textContent = "[x]";

    var handler = makeHideHandler(elt.textContent);

    xNode.addEventListener("click", handler);

    elt.parentNode.appendChild(xNode);

    elt.setAttribute("data-has-block-button", "true");
  }
}

var pageLoadDelay = 1000;

function onUpdate() {
  hideBannedIds();
  addHideButtons();
}

function updateHandler() {
  setTimeout(onUpdate, pageLoadDelay);
}

function addUpdateButtonHook() {
  var elts = document.getElementsByTagName("a");

  for (var i = 0; i < elts.length; i++) {
    var elt = elts[i];

    if (elt.textContent != "Update") continue;

    elt.addEventListener("click", updateHandler);
  }
}

function pageLoop(timeout) {
  onUpdate();
  setTimeout(pageLoop, timeout);
}

addHideButtons();
setTimeout(addUpdateButtonHook, pageLoadDelay);

pageLoop(10000);