Redirector

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Redirector

https://github.com/einaregilsson/Redirector
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// ==UserScript==
// @name         Redirector
// @namespace    https://facaikotei.github.io/
// @version      4.0.0
// @description  https://github.com/einaregilsson/Redirector
// @author       (c)2025 facaikotei (c)2016 Einar Egilsson
// @match        *://*/*
// @grant        GM_getValue
// @grant        GM_setValue
// @require      https://raw.githubusercontent.com/einaregilsson/Redirector/refs/tags/v3.5.2/js/redirect.js#sha256=706cd9538fc6a8417ff7ddf9a65c389600a4a334f0220802632e1411a6432d97
// @icon         https://raw.githubusercontent.com/einaregilsson/Redirector/refs/tags/v3.5.2/images/icon-dark-theme-128.png
// @run-at       document-start
// @license      MIT
// @website      https://greasyfork.org/users/1305953
// ==/UserScript==

var log = console.log;
var partitionedRedirects = {
    main_frame: [
        new Redirect({
            includePattern: 'https://x.com/*',
            redirectUrl: 'https://farside.link/nitter/$1',
            patternType: 'W',
        }),
        new Redirect({
            includePattern: 'https://www.reddit.com/*',
            redirectUrl: 'https://farside.link/redlib/$1',
            patternType: 'W',
        }),
        new Redirect({
            includePattern: '^https://(|[^/]+\\.)medium\\.com/[^?#]*-([0-9a-f]{11,12})(?=$|[?#])',
            redirectUrl: 'https://freedium-mirror.cfd/$2',
            patternType: 'R',
        }),
        new Redirect({
            includePattern: '^https://www\\.pixiv\\.net/(artworks|users)/(\\d+)(?=$|[/?#])',
            redirectUrl: 'https://pixiv.perennialte.ch/$1/$2',
            patternType: 'R',
        }),
        new Redirect({
            includePattern: '^https://(|[^/]+\\.)moegirl\\.[^/]+(/[a-z][^/]*/|/)(.*)',
            excludePattern: '^https://moegirl\\.(icu|uk)/',
            redirectUrl: 'https://moegirl.icu/$3',
            patternType: 'R',
        }),
    ],
};
var ignoreNextRequest = GM_getValue('ignoreNextRequest', {});
var justRedirected = GM_getValue('justRedirected', {});
var redirectThreshold = 3;
var enableNotifications = false;
var sendNotifications = console.log;

//This is the actual function that gets called for each request and must
//decide whether or not we want to redirect.
function checkRedirects(details) {

    //We only allow GET request to be redirected, don't want to accidentally redirect
    //sensitive POST parameters
    if (details.method != 'GET') {
        return {};
    }
    log('Checking: ' + details.type + ': ' + details.url);

    var list = partitionedRedirects[details.type];
    if (!list) {
        log('No list for type: ' + details.type);
        return {};
    }

    var timestamp = ignoreNextRequest[details.url];
    if (timestamp) {
        log('Ignoring ' + details.url + ', was just redirected ' + (new Date().getTime() - timestamp) + 'ms ago');
        delete ignoreNextRequest[details.url];
        return {};
    }


    for (var i = 0; i < list.length; i++) {
        var r = list[i];
        var result = r.getMatch(details.url);

        if (result.isMatch) {

            //Check if we're stuck in a loop where we keep redirecting this, in that
            //case ignore!
            var data = justRedirected[details.url];

            var threshold = 3000;
            if (!data || ((new Date().getTime() - data.timestamp) > threshold)) { //Obsolete after 3 seconds
                justRedirected[details.url] = { timestamp: new Date().getTime(), count: 1 };
            } else {
                data.count++;
                justRedirected[details.url] = data;
                if (data.count >= redirectThreshold) {
                    log('Ignoring ' + details.url + ' because we have redirected it ' + data.count + ' times in the last ' + threshold + 'ms');
                    return {};
                }
            }


            log('Redirecting ' + details.url + ' ===> ' + result.redirectTo + ', type: ' + details.type + ', pattern: ' + r.includePattern + ' which is in Rule : ' + r.description);
            if (enableNotifications) {
                sendNotifications(r, details.url, result.redirectTo);
            }
            ignoreNextRequest[result.redirectTo] = new Date().getTime();

            return { redirectUrl: result.redirectTo };
        }
    }

    return {};
}

(function () {
    'use strict';

    let { redirectUrl } = checkRedirects({
        method: 'GET',
        type: 'main_frame',
        url: location.href,
    });
    GM_setValue('ignoreNextRequest', ignoreNextRequest);
    GM_setValue('justRedirected', justRedirected);
    if (redirectUrl) {
        location.replace(redirectUrl);
    }
})();