// ==UserScript==
// @name         ПУК-СРЕНЬК
// @version      2.1
// @description  Encode and decode 2ch.hk fart code
// @author       Anonymous
// @include      *://2ch.*
// @grant        none
// @run-at       document-end
// ==/UserScript==

const syms = [
    "ПУК",
    "СРЕНЬК",
    "ХРЮК",
    "УИИИ",
    "ЛАХТА",
    "ЛИБЕРАХА",
    "ХОХЛЫ",
    "СВИНОСОБАКА",
    "ШВАЙНОКАРАСЬ",
    "ЛОЛ",
    "КЕК",
    "АБУ",
    "ДВАЧ",
    "ПАРАША",
    "ПОРИДЖ",
    "ХРЮЧЕВО",
    "СВИН",
    "ПЕРДИКС",
    "ПЫНЯ",
    "ЧАЮ",
    "ШУЕ",
    "ЛЕВАК",
    "ПРАВАК",
    "КОМИГЛИСТ",
    "ШВЯТЫЕ",
    "ВАТА",
    "ВОЛОДИН",
    "ДОЛБИЛЬНЯ",
    "ПЕРЕФОРС",
    "КУНЧИК",
    "АВАТАРКА",
    "АНАЛЬЧИК",
];

const keysLen = Math.log2(syms.length);

const symsEncode = () => {
    let result = {};

    syms.forEach((item, index) => {
        result[
            ("0".repeat(keysLen) + index.toString(2)).slice(-keysLen)
        ] = item;
    });

    return result;
};

const symsDecode = () => {
    let result = {};

    Object.entries(symsEncode()).forEach(([key, value]) => {
        result[value] = key;
    });

    return result;
};

const rle = (string) => {
    let arr = string.split("-"),
        encoding = [],
        previous = arr[0],
        count = 1;

    for (let i = 1; i < arr.length; i++) {
        if (arr[i] !== previous) {
            encoding.push(count, previous);
            count = 1;
            previous = arr[i];
        } else {
            count++;
        }
    }

    encoding.push(count, previous);
    return encoding.join("-").replace(/1-/g, "").replace(/(\d)-/g, "$1");
};

const decode = (string) => {
    const data = symsDecode();

    let ba = string
        .split("-")
        .map((item) => {
            const count = /(\d*)(\w+)-?/.exec(item);

            if (count) {
                const key = item.replace(count[0], "");
                return data[key].repeat(parseInt(count[0]));
            }

            return data[item];
        })
        .join("");

    const padLen = ba.length % 8;
    ba = ba.substring(0, ba.length - padLen);

    return new TextDecoder().decode(
        new Uint8Array(ba.match(/.{1,8}/g).map((c) => parseInt(c, 2)))
    );
};

const encode = (string) => {
    let ba = new TextEncoder()
        .encode(string)
        .reduce((s, b) => s + b.toString(2).padStart(8, "0"), "");

    const padLen = keysLen - (ba.length % keysLen);
    ba = ba + "0".repeat(padLen);

    const data = symsEncode();

    return rle(
        ba
            .match(new RegExp(`.{1,${keysLen}}`, "g"))
            .map((item) => {
                return data[item];
            })
            .join("-")
    );
};

(() => {
    const parse = (node) => {
        const post = node.querySelector(".post__message");
        if (post && post.textContent) {
            const words = post.textContent
                .replace(/\t+/g, "")
                .split(/[\n,\s]+/);
            const re = new RegExp(
                `(\\d+)?(${syms.join("|")})\-(\\S+)\-(\\d+)?(${syms.join("|")})`
            );

            words.forEach((word) => {
                post.innerHTML = post.innerHTML.replace(re, (m) => {
                    try {
                        const thread = node.parentElement.parentElement.id.replace(
                            /thread-/,
                            ""
                        );
                        const board = window.location.pathname.split("/")[1];

                        return `<span style="color:green;font-size:1.21em">${decode(
                            m
                        )
                            .replace(/<.*?>/g, "[Я у мамы идиот]")
                            .replace(
                                /(\b(https?|ftp):\/\/[-A-Z0-9+&@#\/%?=~_|!:,.;]*[-A-Z0-9+&@#\/%=~_|])/gim,
                                '<a href="$1" target="_blank" target="_blank" rel="nofollow noopener noreferrer">$1</a>'
                            )
                            .replace(
                                /(^|[^\/])(www\.[\S]+(\b|$))/gim,
                                '$1<a href="http://$2" target="_blank" rel="nofollow noopener noreferrer">$2</a>'
                            )
                            .replace(
                                /(([a-zA-Z0-9\-\_\.])+@[a-zA-Z\_]+?(\.[a-zA-Z]{2,6})+)/gim,
                                '<a href="mailto:$1" target="_blank" rel="nofollow noopener noreferrer">$1</a>'
                            )
                            .replace(
                                /\>>(\d{9})/gim,
                                '<a href="/' +
                                    board +
                                    "/res/" +
                                    thread +
                                    '.html#$1" class="post-reply-link" data-thread="' +
                                    thread +
                                    '" data-num="$1">&gt;&gt;$1</a>'
                            )
                            .replace(/\n/g, "<br>")}</span>`;
                    } catch (err) {
                        return m;
                    }
                });
            });
        }
    };

    const encodeAction = (e) => {
        e.preventDefault();

        const comment = e.target.parentElement.parentElement.querySelector('[name="comment"]');
        const selection = comment.value.substring(
            comment.selectionStart,
            comment.selectionEnd
        );

        if (selection) {
            const encoded = encode(selection);
            const start = comment.selectionStart;
            comment.value =
                comment.value.slice(0, start) +
                encoded +
                comment.value.slice(comment.selectionEnd);
            comment.focus();
            comment.setSelectionRange(start, start + encoded.length);
        } else {
            comment.value = encode(comment.value);
        }
    };

    const decodeAction = (e) => {
        e.preventDefault();

        try {
            const comment = e.target.parentElement.parentElement.querySelector('[name="comment"]');
            const selection = comment.value.substring(
                comment.selectionStart,
                comment.selectionEnd
            );

            if (selection) {
                const decoded = decode(selection);
                const start = comment.selectionStart;
                comment.value =
                    comment.value.slice(0, start) +
                    decoded +
                    comment.value.slice(comment.selectionEnd);
                comment.focus();
                comment.setSelectionRange(start, start + decoded.length);
            } else {
                comment.value = decode(comment.value);
            }
        } catch (err) {}
    };

    const initialPosts = document.querySelectorAll(".post");
    if (initialPosts) {
        initialPosts.forEach((post) => parse(post));
    }

    const observer = new MutationObserver((o) => {
        o.forEach((i) => {
            if (i.addedNodes) {
                i.addedNodes.forEach((n) => parse(n));
            }
        });
    });
    const config = { childList: true };

    const newPosts = document.querySelector(".thread");
    if (newPosts) {
        observer.observe(newPosts, config);
    }

    const rePosts = document.querySelector("#posts-form");
    if (rePosts) {
        observer.observe(rePosts, config);
    }

    let enBtnTopBottom = document.createElement("input");
    enBtnTopBottom.className = "button";
    enBtnTopBottom.type = "button";
    enBtnTopBottom.style = "color:green";
    enBtnTopBottom.value = `Кодировать`;
    enBtnTopBottom.addEventListener("click", encodeAction);

    const enQuick = enBtnTopBottom.cloneNode(true);
    enQuick.addEventListener("click", encodeAction);

    let deBtnTopBottom = document.createElement("input");
    deBtnTopBottom.className = "button";
    deBtnTopBottom.type = "button";
    deBtnTopBottom.style = "color:red";
    deBtnTopBottom.value = `Декодировать`;
    deBtnTopBottom.addEventListener("click", decodeAction);

    const deQuick = deBtnTopBottom.cloneNode(true);
    deQuick.addEventListener("click", decodeAction);

    const topBottomForm = document.querySelector("#postform .postform__raw.desktop:not(.options)");
    if (topBottomForm) {
        topBottomForm.append(enBtnTopBottom);
        topBottomForm.append("\n");
        topBottomForm.append(deBtnTopBottom);
    }

    const quickForm = document.querySelector("#qr-postform .postform__raw.desktop");
    if (quickForm) {
        quickForm.append(enQuick);
        quickForm.append("\n");
        quickForm.append(deQuick);
    }
})();