Adds an extra column to covid tracker

covid19tracker.js

// ==UserScript==
// @name         Covid19 Add Column
// @namespace    http://brennan.sh/
// @version      1.0
// @description  Adds a column of statistics to covid19vaccine tracker
// @author       Brennan
// @match        https://covid19tracker.ca/vaccinationtracker.html
// @icon         https://www.google.com/s2/favicons?domain=covid19tracker.ca
// @grant        none
// @run-at      document-idle
// ==/UserScript==
(function() {
    'use strict';
    const CANADA_POPULATION = 37590000;
    const NEW_HEADER_TEXT = 'Percent who have recieved at least one dose';
    const VACCINE_PROVINCE_TABLE_ID = 'vaccinationsProvinceTable';
    const DATA_TABLE_ID = 'dataTable2';
    const formatPercentString = (percent) => {
        return (((percent).toString() !== 'NaN') ? `${(percent).toString()}%` : 'N/A')
    };
    const populationDict = {
        'Ontario': 14570000,
        'Quebec': 8485000,
        'British Columbia': 5071000,
        'Alberta': 4370000,
        'Manitoba': 1369000,
        'Saskatchewan': 1174000,
        'New Brunswick': 776827,
        'Nova Scotia': 971395,
        'Newfoundland and Labrador': 521542,
        'Northwest Territories': 44826,
        'Yukon': 35874,
        'Nunavut': 38780,
        'Prince Edward Island': 156947,
        'Canada': 37590000,
    };

    const createTableCell = (textContent, parent, element = 'td') => {
        const newCol = document.createElement(element);
        newCol.textContent = textContent
        parent.appendChild(newCol);
    };

    const render = () => {
        const vaccinationsProvinceTable = document.getElementById(VACCINE_PROVINCE_TABLE_ID);
        if (vaccinationsProvinceTable.children.length !== 0) {
            const dataTable2 = document.getElementById(DATA_TABLE_ID);
            const totalDosesCanada = parseInt(dataTable2.children[1].children[0].children[1].textContent.split(' ')[0].replaceAll(',', ''));
            const fullyVaccinatedCanada = parseInt(dataTable2.children[1].children[0].children[5].textContent.split(' ')[0].replaceAll(',', ''));
            const percentCanada = Math.round(((totalDosesCanada - fullyVaccinatedCanada) / CANADA_POPULATION) * 10000) / 100;

            for (let i = 0; i < vaccinationsProvinceTable.children.length; i++) {
                const parentRow = vaccinationsProvinceTable.children[i];
                const province = parentRow.children[0].textContent.trim();
                const totalDoses = parseInt(parentRow.children[1].textContent.split(' ')[0].replaceAll(',', ''));
                const fullyVaccinated = parseInt(parentRow.children[5].textContent.split(' ')[0].replaceAll(',', ''));
                const rowPercent = Math.round(((totalDoses - fullyVaccinated) / populationDict[province]) * 10000) / 100;

                createTableCell(formatPercentString(rowPercent), vaccinationsProvinceTable.children[i]);
            }

            createTableCell(NEW_HEADER_TEXT, dataTable2.children[0].children[0], 'th');
            createTableCell(formatPercentString(percentCanada), dataTable2.children[1].children[0]);

            // Only run once after table has been populated.
            clearInterval(interval);
        }
    }

    render();
    const interval = setInterval(render, 500);
})();