Reddit: Highlight New Comments

Emulate the Reddit Gold feature of highlighting new comments since your last visit.

K instalaci tototo skriptu si budete muset nainstalovat rozšíření jako Tampermonkey, Greasemonkey nebo Violentmonkey.

You will need to install an extension such as Tampermonkey to install this script.

K instalaci tohoto skriptu si budete muset nainstalovat rozšíření jako Tampermonkey nebo Violentmonkey.

K instalaci tohoto skriptu si budete muset nainstalovat rozšíření jako Tampermonkey nebo Userscripts.

You will need to install an extension such as Tampermonkey to install this script.

K instalaci tohoto skriptu si budete muset nainstalovat manažer uživatelských skriptů.

(Už mám manažer uživatelských skriptů, nechte mě ho nainstalovat!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

(Už mám manažer uživatelských stylů, nechte mě ho nainstalovat!)

// ==UserScript==
// @name            Reddit: Highlight New Comments
// @description     Emulate the Reddit Gold feature of highlighting new comments since your last visit.
// @author          Chris H (Zren / Shade)
// @icon            https://reddit.com/favicon.ico
// @namespace       https://github.com/Zren
// @version         2
// @include         /https?:\/\/((www|pay|[a-z]{2})\.)?reddit\.com\/r\/[a-zA-Z0-9]+\/comments\/.*/
// @grant           GM_addStyle
// ==/UserScript==

// Based on:
//		https://greasyfork.org/scripts/1868-reddit-highlight-newest-comments/code/Reddit%20highlight%20newest%20comments.user.js


(function(uw) {
    //--- Settings
    var threadTTL = 3 * 24 * 60 * 60 * 1000; // 3 Days
    var applyStyle = true; // Set to true to overload Reddit's default styling of new comments with the style below.
    
    // Remove .res-commentBoxes if you're not using RES.
    var style = " \
.res-commentBoxes .new-comment .usertext-body { \
background-color: transparent; \
border: 0; \
margin: 0; \
} \
\
.res-commentBoxes .comment.new-comment, \
.res-commentBoxes .comment .comment .comment.new-comment, \
.res-commentBoxes .comment .comment .comment .comment .comment.new-comment, \
.res-commentBoxes .comment .comment .comment .comment .comment .comment .comment.new-comment, \
.res-commentBoxes .comment .comment .comment .comment .comment .comment .comment .comment .comment.new-comment \
{ background-color: #f2f8ff !important; border: solid 1px #d6e3f3 !important; } \
\
.res-commentBoxes .comment .comment.new-comment, \
.res-commentBoxes .comment .comment .comment .comment.new-comment, \
.res-commentBoxes .comment .comment .comment .comment .comment .comment.new-comment, \
.res-commentBoxes .comment .comment .comment .comment .comment .comment .comment .comment.new-comment, \
.res-commentBoxes .comment .comment .comment .comment .comment .comment .comment .comment .comment .comment.new-comment \
{ background-color: #e5efff !important; border: solid 1px #cddaf3 !important; } \
";
    
    //--- Variables
    var nowAtLoad = Date.now();
    var lastVisitedAtLoad = null;
    
    //--- Functions
    var getThreadId = function() {
        var element = document.querySelector('[rel="shorturl"]');
        if (!element)
            return null;
        return "redd_id_" + element.href.substr(-6);
    };
    
    var setThreadLastVisited = function(threadId, t) {
        if (typeof t === 'object' && t.getTime) { // Date
            t = t.getTime();
        }
        localStorage.setItem(threadId, t);
        console.log('set localStorage["' + threadId + '"] = ', t);
    };
    
    var getThreadLastVisited = function(threadId) {
        var t = localStorage.getItem(threadId);
        t = parseInt(t, 10);
        //console.log('get localStorage["' + threadId + '"] = ', t);
        return t;
    };
    
    var deleteThreadLastVisited = function(threadId) {
        localStorage.removeItem(threadId);
        console.log('del localStorage["' + threadId + '"]');
    };
    
    var highlightNewCommentsSince = function(t) {
        $('.comment').each(function(i, comment) {
            var $comment = $(comment);
            if ($comment.hasClass('deleted'))
                return;
            
            var $commentTime = $comment.children('.entry').children('.tagline').children('time');
            var commentTime = $commentTime.attr('datetime');
            commentTime = new Date(commentTime);
            
            if (commentTime > t) {
                $comment.addClass('new-comment');
            } else {
                $comment.removeClass('new-comment');
            }
        });
    };
    
    
    var updateLastVisited = function() {
        var threadId = getThreadId();
        var threadLastVisited = getThreadLastVisited(threadId);
        if (threadLastVisited) {
            highlightNewCommentsSince(threadLastVisited);
        } else {
        	threadLastVisited = nowAtLoad;
        }
        setThreadLastVisited(threadId, nowAtLoad);
        lastVisitedAtLoad = threadLastVisited;
    };
    
    var purgeExpiredData = function() {
        var keys = Object.keys(localStorage);
        var threadIdRegex = /redd_id_([a-zA-Z0-9]{6})/;
        // Filter out non threadLastVisited keys.
        keys = keys.filter(function(key) {
            return threadIdRegex.test(key);
        });
        // Filter out non expired keys.
        keys = keys.filter(function(threadId) {
            var threadLastVisited = getThreadLastVisited(threadId);
            return nowAtLoad - threadTTL >= threadLastVisited; // Return true if it has expired.
        });
        keys.forEach(function(threadId) {
            deleteThreadLastVisited(threadId);
        });
    };
    
    var update = function() {
        if (lastVisitedAtLoad) {
            highlightNewCommentsSince(lastVisitedAtLoad);
        } else {
        	updateLastVisited();
        }
        purgeExpiredData();
    };
    
    //--- Main
    if (!getThreadId())
        return;
    
    // Wrap the function called when requesting more comments.
    var reddit_morechildren = uw.morechildren.__origional__ || uw.morechildren;
    uw.morechildren = function() {
        reddit_morechildren.apply(this, arguments);
        setTimeout(update, 1000);
    };
    uw.morechildren.__origional__ = reddit_morechildren;

    // Overwrite Reddit's default styling.
    if (applyStyle)
        GM_addStyle(style);
    
    update();
    
})(typeof unsafeWindow !== 'undefined' ? unsafeWindow : window);