☰

Reddit Advanced Content Filter

Automatically hides posts in your Reddit feed based on keywords or subreddits you specify

// ==UserScript==
// @name Reddit Advanced Content Filter
// @namespace https://greasyfork.org/en/users/567951-stuart-saddler
// @version 2.4
// @description Automatically hides posts in your Reddit feed based on keywords or subreddits you specify
// @author Stuart Saddler
// @license MY
// @icon https://clipart-library.com/images_k/smoke-clipart-transparent/smoke-clipart-transparent-6.png
// @supportURL https://greasyfork.org/en/users/567951-stuart-saddler
// @match *://www.reddit.com/*
// @match *://old.reddit.com/*
// @run-at document-end
// @grant GM.getValue
// @grant GM.setValue
// @grant GM_addStyle
// @grant GM_registerMenuCommand
// @grant GM_unregisterMenuCommand
// ==/UserScript==

(async function() {
    'use strict';

    const postSelector = 'article, div[data-testid="post-container"], shreddit-post';
    let filteredCount = 0;
    let menuCommand = null;
    let processedPosts = new WeakSet();
    let blocklistArray = [];
    let keywordPattern = null;
    let pendingUpdates = 0;

    const batchUpdateCounter = debounce(() => {
        if (typeof GM_registerMenuCommand !== 'undefined') {
            if (menuCommand !== null) {
                GM_unregisterMenuCommand(menuCommand);
            }
            menuCommand = GM_registerMenuCommand(
                `Configure Blocklist (${filteredCount} blocked)`,
                showConfig
            );
        } else {
            createFallbackButton();
        }
    }, 16);

    const cleanup = () => {
        if (pendingUpdates === 0) return;
        pendingUpdates = 0;
        batchUpdateCounter();
    };

    setInterval(cleanup, 1000);

    const CSS = `
        .content-filtered { display: none !important; height: 0 !important; overflow: hidden !important; }
        .reddit-filter-dialog { position: fixed; top: 50%; left: 50%; transform: translate(-50%, -50%); background: white; padding: 20px; border-radius: 8px; z-index: 1000000; box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15); min-width: 300px; max-width: 350px; font-family: Arial, sans-serif; color: #333; }
        .reddit-filter-dialog h2 { margin-top: 0; color: #0079d3; font-size: 1.5em; font-weight: bold; }
        .reddit-filter-dialog p { font-size: 0.9em; margin-bottom: 10px; color: #555; }
        .reddit-filter-dialog textarea { width: calc(100% - 16px); height: 150px; padding: 8px; margin: 10px 0; border: 1px solid #ccc; border-radius: 4px; font-family: monospace; background: #f9f9f9; color: #000; resize: vertical; }
        .reddit-filter-dialog .button-container { display: flex; justify-content: flex-end; gap: 10px; margin-top: 10px; }
        .reddit-filter-dialog button { display: flex; align-items: center; justify-content: center; padding: 8px 16px; border: none; border-radius: 4px; cursor: pointer; font-size: 1em; text-align: center; }
        .reddit-filter-dialog .save-btn { background-color: #0079d3; color: white; }
        .reddit-filter-dialog .cancel-btn { background-color: #f2f2f2; color: #333; }
        .reddit-filter-dialog button:hover { opacity: 0.9; }
        .reddit-filter-overlay { position: fixed; top: 0; left: 0; right: 0; bottom: 0; background: rgba(0, 0, 0, 0.5); z-index: 999999; }
    `;

    if (typeof GM_addStyle !== 'undefined') {
        GM_addStyle(CSS);
    } else {
        const style = document.createElement('style');
        style.textContent = CSS;
        document.head.appendChild(style);
    }

    const getKeywordPattern = (keywords) => {
        const escapedKeywords = keywords.map(k => k.replace(/[.*+?^${}()|[\]\\]/g, '\\$&')).join('|');
        return new RegExp(`\\b(${escapedKeywords})(s|es|ies)?\\b`, 'i');
    };

    async function showConfig() {
        const overlay = document.createElement('div');
        overlay.className = 'reddit-filter-overlay';
        const dialog = document.createElement('div');
        dialog.className = 'reddit-filter-dialog';
        dialog.innerHTML = `
            <h2>Reddit Filter: Blocklist</h2>
            <p>Enter keywords or subreddit names one per line. Filtering is case-insensitive.</p>
            <p><em>Keywords can match common plural forms (e.g., "apple" blocks "apples"). Irregular plurals (e.g., "mouse" and "mice") must be added separately. Subreddit names should be entered without the "r/" prefix (e.g., "subredditname").</em></p>
            <textarea spellcheck="false" id="blocklist">${blocklistArray.join('\n')}</textarea>
            <div class="button-container">
                <button class="cancel-btn">Cancel</button>
                <button class="save-btn">Save</button>
            </div>
        `;

        document.body.appendChild(overlay);
        document.body.appendChild(dialog);

        const closeDialog = () => {
            dialog.remove();
            overlay.remove();
        };

        dialog.querySelector('.save-btn').addEventListener('click', async () => {
            const blocklistInput = dialog.querySelector('#blocklist').value;
            blocklistArray = blocklistInput
                .split('\n')
                .map(item => item.trim().toLowerCase())
                .filter(item => item.length > 0);
            keywordPattern = getKeywordPattern(blocklistArray);
            await GM.setValue('blocklist', blocklistArray);
            closeDialog();
            location.reload();
        });

        dialog.querySelector('.cancel-btn').addEventListener('click', closeDialog);
        overlay.addEventListener('click', closeDialog);
    }

    function createFallbackButton() {
        const button = document.createElement('button');
        button.innerHTML = `Configure Blocklist (${filteredCount} blocked)`;
        button.style.cssText = 'position:fixed;top:10px;right:10px;z-index:999999;padding:8px;';
        button.addEventListener('click', showConfig);
        document.body.appendChild(button);
    }

    async function processPostsBatch(posts) {
        const batchSize = 5;
        for (let i = 0; i < posts.length; i += batchSize) {
            const batch = posts.slice(i, i + batchSize);
            await new Promise(resolve => requestIdleCallback(resolve, { timeout: 1000 }));
            batch.forEach(post => processPost(post));
        }
    }

    function processPost(post) {
        if (!post || processedPosts.has(post)) return;
        processedPosts.add(post);

        let shouldHide = false;
        const subredditElement = post.querySelector('a[data-click-id="subreddit"], a.subreddit');

        if (subredditElement) {
            const subredditName = subredditElement.textContent.trim().replace(/^r\//i, '').toLowerCase();
            if (blocklistArray.includes(subredditName)) {
                shouldHide = true;
            }
        }

        if (!shouldHide && blocklistArray.length > 0) {
            const postContent = post.textContent.toLowerCase();
            shouldHide = keywordPattern.test(postContent);
        }

        if (shouldHide) {
            post.classList.add('content-filtered');
            const parentArticle = post.closest(postSelector);
            if (parentArticle) {
                parentArticle.classList.add('content-filtered');
            }
            filteredCount++;
            pendingUpdates++;
            batchUpdateCounter();
        }
    }

    const debouncedUpdate = debounce((posts) => {
        processPostsBatch(Array.from(posts));
    }, 100);

    function debounce(func, wait) {
        let timeout;
        return (...args) => {
            clearTimeout(timeout);
            timeout = setTimeout(() => {
                timeout = null;
                func.apply(this, args);
            }, wait);
        };
    }

    async function init() {
        blocklistArray = (await GM.getValue('blocklist', [])).map(item => item.toLowerCase());
        keywordPattern = getKeywordPattern(blocklistArray);
        batchUpdateCounter();

        const observerTarget = document.querySelector('.main-content') || document.body;
        const observer = new MutationObserver(mutations => {
            const newPosts = new Set();
            mutations.forEach(mutation => {
                mutation.addedNodes.forEach(node => {
                    if (node.nodeType === Node.ELEMENT_NODE) {
                        if (node.matches?.(postSelector)) {
                            newPosts.add(node);
                        }
                        node.querySelectorAll?.(postSelector).forEach(post => newPosts.add(post));
                    }
                });
            });
            if (newPosts.size > 0) {
                debouncedUpdate(newPosts);
            }
        });

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

        const initialPosts = document.querySelectorAll(postSelector);
        if (initialPosts.length > 0) {
            debouncedUpdate(initialPosts);
        }
    }

    await init();
})();