Twitter media-only filter toggle.

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Twitter media-only filter toggle.

Toggle non-media tweets on and off on the home timeline, for the power-viewer!
Ask a question, post a review, or report the script.
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// ==UserScript==
// @name         Twitter media-only filter toggle.
// @version      0.22
// @description  Toggle non-media tweets on and off on the home timeline, for the power-viewer!
// @author       Cro
// @match        https://*.twitter.com/*
// @match        https://*.x.com/*
// @run-at       document-idle
// @grant        GM_setValue
// @grant        GM_getValue
// @namespace https://greasyfork.org/users/10865
// @icon         https://www.google.com/s2/favicons?domain=twitter.com
// @license      MIT
// ==/UserScript==
/* jshint esversion: 6 */

(function() {
    'use strict';
    let storage_key = 'cro-media-toggle';
    let show_all = GM_getValue(storage_key);

    let create_ui = function(target)
    {
        let button = document.createElement('button');
        button.innerText = show_all ? 'Showing all home tweets' : 'Showing only media home tweets';
        button.onclick = function(event)
        {
            show_all = !show_all;
            GM_setValue(storage_key, show_all);
            location.reload();
        };
        target.prepend(button);
    };

    let walk_objects = function*(obj)
    {
        let stack = Object.entries(obj);
        while (stack.length > 0)
        {
            let entry = stack.pop();
            yield entry;
            if (entry[1] != null && typeof(entry[1]) == 'object')
            {
                stack = stack.concat(Object.entries(entry[1]));
            }
        }
    };

    let find_objects_at_keys = (obj, keys) => Array.from(walk_objects(obj)).filter(e => keys.includes(e[0])).map(e => e[1]);
    let any_key_in_obj = (obj, keys) => Array.from(walk_objects(obj)).some(e => keys.includes(e[0]));
    let target_entry_types = ['tweet-', 'promoted-tweet-', 'home-conversation-'];
    let media_types = ['media', 'card'];
    let has_media = (obj) => !target_entry_types.some(e => obj.entryId.startsWith(e)) || any_key_in_obj(obj, media_types);

    let update_data = function(data)
    {
        if (show_all || location.pathname != '/home')
        {
            return;
        }
        for (let obj of find_objects_at_keys(data, ['instructions']))
        {
            for (let subobj of obj)
            {
                if (subobj.hasOwnProperty('entries'))
                {
                    subobj.entries = subobj.entries.filter(has_media);
                }
            }
        }
    };

    let old_parse = JSON.parse;
    let unsafe_window_parse = unsafeWindow.JSON.parse;
    let new_unsafe_window_parse = function(string)
    {
        let data = old_parse(string);
        try
        {
            if (data != null)
            {
                update_data(data);
            }
        }
        catch(error)
        {
            console.log(error);
        }
        return unsafe_window_parse(JSON.stringify(data));;
    };
    exportFunction(new_unsafe_window_parse, unsafeWindow.JSON, { defineAs: 'parse' });

    // Wait for twitter's react crap finish loading things.
    let scan_interval = setInterval(function()
    {
        let target = document.body.querySelector('nav[role="navigation"]');
        if (target)
        {
            clearInterval(scan_interval);
            create_ui(target);
        }
    }, 10);
})();