// ==UserScript==
// @name     4chan2reddit
// @grant GM.getValue
// @grant GM.setValue
// @version  1
// @description Destroy free speech and rely on the discernment of children
// @include      *://boards.4chan.org/*
// @include      *://boards.4channel.org/*
// ==/UserScript==

// User preferences will be loaded.
const defaultMin = "-10";
const defaultMax = "10";
var thresholdMinPreference = defaultMin;
var thresholdMaxPreference = defaultMax;

function generateRandomColor() {
  return `rgb(${Math.floor((Math.random() * 256 + 255) / 2)},${Math.floor((Math.random() * 256 + 255) / 2)},${Math.floor((Math.random() * 256 + 255) / 2)})`;
}

// The script will read posts and apply rules when it sees "+1", "-1", and #hashtags.
const upvoteFilter = /\s\+\d+\s|up(vot|doot|boat)|t ?h ?a ?n ?k ?(y ?o ?)?[su]|bump|s(au|our)ce|good ?job|\b(I l(ov|ik)e|based|nice|cool|cute|qt|haha|lmao|kek|patrician|.pbp\b|lol\b)/i;
const downvoteFilter = /\s\-\d+\s|down(vot|doot|boat)|\bkys\b|touch.*grass|\bcringe\b|\bcope\b|f[a]g|gay|reddit|kil+ yourself|f.ck|r.tard|nig(s|ger)|j[e]w|\bb(8|ait)\b|schizo|stfu|rent.?free|cancer|\bloser/i;
const tagSearchQuery = /[^0-9a-z]#([0-9a-z]{2,})/gi;

function voteAndTag(reply, replyText, post) {
  if (!post || !replyText) return;
  replyText = ` ${replyText} `;
  const upvoted = replyText.match(upvoteFilter);
  const downvoted = replyText.match(downvoteFilter);
  const tags = replyText.match(tagSearchQuery);
  if (post !== reply)
    if (upvoted && (!replyText.includes("-1") || replyText.includes("+1"))) post.voteScore++;
    else if (downvoted) post.voteScore--;
  for (let i = 0; i < tags?.length; i++) {
    const tag = post.tags[tags[i].toString().trim().toLowerCase()] || {
      tag: tags[i].toString().trim(),
      count: 0,
      color: generateRandomColor(),
    };
    tag.count++;
    post.tags[tags[i].toString().trim().toLowerCase()] = tag;
  }
}

function updateScores() {
  // User preferences will be stored.
  const thresholdMin0 = document.getElementById("thresholdMin0");
  const thresholdMin1 = document.getElementById("thresholdMin1");
  const thresholdMax0 = document.getElementById("thresholdMax0");
  const thresholdMax1 = document.getElementById("thresholdMax1");

  if (thresholdMin0 && thresholdMin0.value !== thresholdMinPreference) {
    thresholdMinPreference = thresholdMin0.value || thresholdMinPreference || defaultMin;
    GM.setValue("minThreshold", thresholdMinPreference);
  } else if (thresholdMin1 && thresholdMin1.value !== thresholdMinPreference) {
    thresholdMinPreference = thresholdMin1.value || thresholdMinPreference || defaultMin;
    GM.setValue("minThreshold", thresholdMinPreference);
  }

  if (parseInt(thresholdMinPreference) > parseInt(thresholdMaxPreference)) {
    thresholdMaxPreference = thresholdMinPreference;
    if (thresholdMax0) thresholdMax0.value = thresholdMaxPreference;
    if (thresholdMax1) thresholdMax1.value = thresholdMaxPreference;
    GM.setValue("maxThreshold", thresholdMaxPreference);
  }

  if (thresholdMax0 && thresholdMax0.value !== thresholdMaxPreference) {
    thresholdMaxPreference =
      thresholdMax0.value || thresholdMaxPreference || defaultMax;
    GM.setValue("maxThreshold", thresholdMaxPreference);
  } else if (thresholdMax1 && thresholdMax1.value !== thresholdMaxPreference) {
    thresholdMaxPreference =
      thresholdMax1.value || thresholdMaxPreference || defaultMax;
    GM.setValue("maxThreshold", thresholdMaxPreference);
  }

  if (parseInt(thresholdMinPreference) > parseInt(thresholdMaxPreference)) {
    thresholdMinPreference = thresholdMaxPreference;
    GM.setValue("minThreshold", thresholdMinPreference);
  }

  if (thresholdMin0) thresholdMin0.value = thresholdMinPreference;
  if (thresholdMin1) thresholdMin1.value = thresholdMinPreference;
  if (thresholdMax0) thresholdMax0.value = thresholdMaxPreference;
  if (thresholdMax1) thresholdMax1.value = thresholdMaxPreference;

  // Posts are upvoted, downvoted, and tagged by replies, so tabulate votes by most recent.
  const posts = [...document.getElementsByClassName("postMessage")].filter(
    (p) => !p.id.includes("_")
  );
  posts.forEach((p) => {
    p.voteScore = 0;
    if (p.tags) Object.keys(p.tags).forEach((k) => (p.tags[k].count = 0));
    else p.tags = {};
  });
  const oldTags = document.getElementsByClassName("tag");
  while (oldTags.length > 0) {
    oldTags[0].parentNode.removeChild(oldTags[0]);
  }
  for (let i = posts.length - 1; i >= 0; i--) {
    const post = posts[i];
    const op = post.parentElement.parentElement.parentElement.getElementsByClassName("postMessage")[0];
    // Parse replies to posts into votes and tags.
    let replyTo = {};
    let currentTargets = [];
    let hasData = false;
    // Segment replies by quote links
    for (let j = 0; j < post.childNodes.length; j++) {
      const node = post.childNodes[j];
      if (node.className?.startsWith("quotelink")) {
        if (hasData) {
          currentTargets = [];
          hasData = false;
        }
        let currentTarget = node.hash.substring(2);
        currentTargets.push(currentTarget);
        if (!replyTo[currentTarget]) replyTo[currentTarget] = "";
      } else if (node.data) {
        if (!currentTargets.length) {
          // Posters reply to OP by default.
          let currentTarget = op.id.substring(1);
          currentTargets = [currentTarget];
          if (!replyTo[currentTarget]) replyTo[currentTarget] = "";
        }
        currentTargets.forEach((currentTarget) => {
          replyTo[currentTarget] += node.data + " ";
        });
        hasData = true;
      }
    }
    Object.keys(replyTo).forEach((r) => {
      voteAndTag(
        post,
        replyTo[r],
        posts.find((p) => p.id.substring(1) === r)
      );
    });

    // Posts outside the user's thresholds will be hidden.
    if (post.voteScore < parseInt(thresholdMinPreference) ||
      post.voteScore > parseInt(thresholdMaxPreference)
    ) {
      if (post.parentElement.classList.contains("op")) {
        post.parentElement.parentElement.parentElement.style.display = "none";
        post.parentElement.parentElement.parentElement.nextElementSibling.style.display = "none";
      } else post.parentElement.parentElement.style.display = "none";
    } else {
      if (post.parentElement.classList.contains("op")) {
        post.parentElement.parentElement.parentElement.style = "";
        post.parentElement.parentElement.parentElement.nextElementSibling.style = "";
      } else post.parentElement.parentElement.style = "";
      // Individual posts will add a vote total and a tag cloud.
      let total = document.getElementById("total" + post.id.substring(1));
      let votes = document.getElementById("votes" + post.id.substring(1));
      if (!total) {
        const postQuote = ">>" + post.id.substring(1) + "\n";
        const upvote = document.createElement("a");
        upvote.addEventListener("click", () => {
          [...document.getElementsByTagName("textArea")].forEach((t) => {
            t.value += (t.value.includes(postQuote) ? " " : postQuote) + "+1";
          });
        });
        upvote.style = "display:inline;color:#0f0;font-weight:bolder;background-color:#888";
        upvote.innerHTML = "&nbsp;⬆&nbsp;";
        const downvote = document.createElement("a");
        downvote.innerHTML = "&nbsp;⬇&nbsp;";
        downvote.addEventListener("click", () => {
          [...document.getElementsByTagName("textArea")].forEach((t) => {
            t.value += (t.value.includes(postQuote) ? " " : postQuote) + "-1";
          });
        });
        downvote.style = "display:inline;color:#f00;font-weight:bolder;background-color:#888";
        total = document.createElement("div");
        total.id = "total" + post.id.substring(1);
        total.style = "display:inline;color:#222";
        votes = document.createElement("div");
        votes.id = "votes" + post.id.substring(1);
        votes.innerHTML = " ";
        votes.className = "totals";
        votes.appendChild(upvote);
        votes.appendChild(downvote);
        votes.appendChild(total);
        post.appendChild(votes);
      }
      votes.style =
        "width:40%" +
        (post.voteScore > 0
          ? ";background-color:#8f8"
          : post.voteScore < 0
          ? ";background-color:#f88"
          : "");
      total.innerHTML = "&nbsp;" + post.voteScore;
        Object.keys(post.tags).forEach((k) => {
          const t = post.tags[k];
          if (t.count < 1) return;
          const tag = document.createElement("div");
          tag.innerHTML = t.tag + (t.count > 1 ? " x" + t.count : "");
          tag.className = "tag";
          tag.style = "display:inline;color:#222;background-color:" + t.color;
          post.appendChild(tag);
          post.innerHTML += " ";
        });
    }
  }
}

GM.getValue("minThreshold", defaultMin).then(async (v) => {
  thresholdMinPreference = v || defaultMin;
  thresholdMaxPreference = (await GM.getValue("maxThreshold", defaultMax)) || defaultMax;
  updateScores();
  setTimeout(() => {
    const navLinkContainers = document.getElementsByClassName("navLinks");
    for (let i = 0; i < navLinkContainers.length; i++) {
      const mainContainer = document.createElement("div");
      mainContainer.style = "display:inline";
      if (i < 2) {
        // Threshold Min/Max textboxes will be added to the thread.
        const thresholdMin = document.createElement("input");
        thresholdMin.id = "thresholdMin" + i;
        thresholdMin.type = "number";
        thresholdMin.value = thresholdMinPreference;
        const thresholdMinLabel = document.createElement("label");
        thresholdMinLabel.for = thresholdMin.id;
        thresholdMinLabel.innerHTML = "Minimum score";
        mainContainer.innerHTML += " ";
        mainContainer.appendChild(thresholdMinLabel);
        mainContainer.innerHTML += " ";
        mainContainer.appendChild(thresholdMin);
        const thresholdMax = document.createElement("input");
        thresholdMax.id = "thresholdMax" + i;
        thresholdMax.type = "number";
        thresholdMax.value = thresholdMaxPreference;
        const thresholdMaxLabel = document.createElement("label");
        thresholdMaxLabel.for = thresholdMax.id;
        thresholdMaxLabel.innerHTML = "Max";
        mainContainer.innerHTML += " ";
        mainContainer.appendChild(thresholdMaxLabel);
        mainContainer.innerHTML += " ";
        mainContainer.appendChild(thresholdMax);
      }
      navLinkContainers[i].appendChild(mainContainer);
    }
    updateScores();
    setInterval(updateScores, 2000);
  }, 3500);
});