xdhack.user.js

// ==UserScript==
// @name         f-hack
// @namespace    http://tampermonkey.net/
// @version      0.1
// @description  hehe
// @author       dumbasPL
// @match        *.eszkola.opolskie.pl/*
// @grant        none
// ==/UserScript==

function calc(x){

    for(var i = 1; i < x.rows.length; i++){
        var sum = 0;
        var row = x.rows[i];
        for(var j = 1; j < row.cells.length - 1; j++){
            var cell = row.cells[j];
            var num = parseInt(cell.innerHTML);
            if(num) sum += num;
        }
        if(sum > 0) row.cells[row.cells.length - 1].innerHTML = sum;
        else row.cells[x.rows.length - 1].innerHTML = "";
    }

}

var kropka = 'data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAADIAAAAUCAYAAADPym6aAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsMAAA7DAcdvqGQAAACHSURBVFhH7ZZBCoAgEEW9pgfoEq47hLsu4aZLCJ3CbvGL1ELQosDI+A9m5QjzkD8oCCH1gRuhZAe51QALIBxlASbovb+Hcef9r+FF7g/09F41KNKKCDDDqHIWmhGxOkrEShdBEyLpZjpKryahhS9SjdJAv8nIFRSphR8on4Mcn/2iEPJbhFgAXyJEEWgRs3YAAAAASUVORK5CYII=';
var obecnosc = 'Obecność';

var table = document.getElementsByClassName('presentData')[0];
if(table){
    if(table.rows[0].cells[3].innerHTML.indexOf("14.02.2018")){
        for(var i = 1; i < table.rows.length; i++){
            var row = table.rows[i];
            if(row.cells[3].className.length > 0){
                var div = row.cells[3].getElementsByTagName('div')[0];
                div.classList = "x-obecnosc";
                var img = div.getElementsByTagName('img')[0];
                img.src = kropka;
                img.alt = obecnosc;
                img.title = obecnosc;
            }
            if(row.cells[4].className.length > 0){
                var div = row.cells[4].getElementsByTagName('div')[0];
                div.classList = "x-obecnosc";
                var img = div.getElementsByTagName('img')[0];
                img.src = kropka;
                img.alt = obecnosc;
                img.title = obecnosc;
            }
        }
    }
}
var nb = document.getElementById('panel_nieobecnosci');
if(nb) nb.remove();

var x = document.getElementsByTagName('table');
if(x[1]){
    x[1].rows[2].cells[6].innerText = 6;
    x[1].rows[3].cells[6].innerText = 3;
    calc(x[1]);
}