DrownedMods Base64 Auto Decoder のソースコード

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DrownedMods Base64 Auto Decoder

Auto-decodes base64 strings in posts and makes them clickable
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// ==UserScript==
// @name         DrownedMods Base64 Auto Decoder
// @namespace    https://example.com/drownedmods-base64
// @version      1.2
// @description  Auto-decodes base64 strings in posts and makes them clickable
// @author       Adapted from FMHY with help from Grok.ai
// @license MIT 
// @match        https://forum.drownedmods.org/*
// @grant        none
// @run-at       document-end
// ==/UserScript==

(function() {
    'use strict';

    const base64FullRegex = /^[A-Za-z0-9+/]{40,}(={0,2})?$/;

    function looksLikeUrl(str) {
        str = str.trim();
        return /^(https?:\/\/|magnet:\?|ftp:\/\/)/i.test(str) ||
               /mega\.nz|mediafire\.com|drive\.google\.com|gofile\.io|pixeldrain\.com/i.test(str) ||
               str.endsWith('.torrent') || str.includes('?xt=urn:btih:');
    }

    function processTextNode(node) {
        if (node.nodeType !== Node.TEXT_NODE) return;
        const text = node.textContent.trim();
        if (text.length < 40 || !base64FullRegex.test(text)) return;

        let decoded;
        try {
            decoded = atob(text).trim();
        } catch (e) {
            return;
        }

        if (!looksLikeUrl(decoded) && !decoded.includes('http')) return;

        const fragment = document.createDocumentFragment();

        if (!decoded.includes('\n')) {
            const a = document.createElement('a');
            a.href = decoded;
            a.textContent = decoded;
            a.target = '_blank';
            a.rel = 'noopener noreferrer';
            a.style.color = '#00aaff';
            a.style.fontWeight = 'bold';
            fragment.appendChild(document.createTextNode('→ '));
            fragment.appendChild(a);
        } else {
            decoded.split('\n').forEach((line, idx, arr) => {
                const trimmed = line.trim();
                if (!trimmed) {
                    fragment.appendChild(document.createElement('br'));
                    return;
                }
                if (looksLikeUrl(trimmed)) {
                    const a = document.createElement('a');
                    a.href = trimmed;
                    a.textContent = trimmed;
                    a.target = '_blank';
                    a.rel = 'noopener noreferrer';
                    fragment.appendChild(a);
                } else {
                    fragment.appendChild(document.createTextNode(trimmed));
                }
                if (idx < arr.length - 1) fragment.appendChild(document.createElement('br'));
            });
        }

        node.parentNode.replaceChild(fragment, node);
    }

    function walk(node) {
        if (!node) return;

        if (node.nodeType === Node.ELEMENT_NODE &&
            (node.tagName === 'PRE' || node.tagName === 'CODE' ||
             node.classList.contains('message-body') ||
             node.classList.contains('post-body') ||
             node.classList.contains('message-content') ||
             node.classList.contains('content') ||
             node.classList.contains('post-message') ||
             node.tagName === 'BLOCKQUOTE' ||
             node.tagName === 'DIV' || node.tagName === 'P')) {
            Array.from(node.childNodes).forEach(walk);
        }

        if (node.nodeType === Node.TEXT_NODE) {
            processTextNode(node);
        }
    }

    walk(document.body);

    const observer = new MutationObserver(muts => {
        muts.forEach(mut => {
            mut.addedNodes.forEach(node => {
                if (node.nodeType === Node.ELEMENT_NODE) walk(node);
            });
        });
    });

    observer.observe(document.body, { childList: true, subtree: true });

    console.log('[DrownedMods Base64 Decoder] Running – looking for encoded links');
})();