rower-website/public/js/app.js

A web server which access the PM5 rowing machine over usb and displays the wattage value.

var socket = io();
let wattage = 0;
let startWattage = wattage;
let lastWattage = wattage;
let maxWattage = wattage;
let average = 0;

let sum = 0; // Variable to store the sum of values
let count = 0; // Variable to store the number of values

function computeCumulativeAverage(newValue) {
    sum += newValue;
    count++;
    return sum / count;
}

function computeMaxWattage(newValue) {
    if (newValue > maxWattage) {
        maxWattage = newValue; // Update lastMaxWattage if newValue is greater
    }
    return maxWattage; // Return the computed maximum wattage
}

document.addEventListener("DOMContentLoaded", function() {
    var countdownElement = document.getElementById("countdown");
    var tenthsCountdownElement = document.getElementById("tenthsCountdown");

    var countdownDuration = 5;
    var initialMessage = "Ready?";

    countdownElement.textContent = initialMessage;

    function startCountdown() {
        var countdown = countdownDuration;
        var countdownInterval = setInterval(function() {
            countdown--;
            if (countdown > 1) {
                countdownElement.textContent = (countdown-1).toString();
            }   else if (countdown === 1){
                countdownElement.textContent = "Go!";


                // Start the tenths of a second countdown
                startTenthsCountdown();
            } else {
                countdownElement.textContent = "";
                clearInterval(countdownInterval);
            }
        }, 1000);
    }

    function startTenthsCountdown() {
        var tenthsCountdown = 100;
        var tenthsCountdownInterval = setInterval(function() {
            tenthsCountdown--;
            var seconds = Math.floor(tenthsCountdown / 10);
            var tenths = tenthsCountdown % 10;
            tenthsCountdownElement.textContent = seconds + "." + tenths;
            if (tenthsCountdown > 0) {
                socket.on('usbData', function(number) {
                    wattage = number;
                    maxWattage = Math.round(computeMaxWattage(wattage));
                    average = Math.round(computeCumulativeAverage(wattage));
                    
                    document.getElementById('wattage').textContent = 'Wattage: ' + wattage +"W";
                    document.getElementById('max').textContent = 'Peak: ' + maxWattage +"W";
                    document.getElementById('average').textContent = 'Average: ' + average +"W";
                    // Function to update the bar chart
                    function updateChart() {
                        document.getElementById('current-bar').style.bottom = `${wattage/7}%`;
                        document.getElementById('average-bar').style.bottom = `${average/7}%`;
                        document.getElementById('peak-bar').style.bottom = `${maxWattage/7}%`;

                    }

                    // Call the updateChart function to initialize the chart
                    updateChart();
                  });
            }
            if (tenthsCountdown <= 0) {
                clearInterval(tenthsCountdownInterval);
                tenthsCountdownElement.textContent = "STOP!";
            }
        }, 100);
    }

    startCountdown();
});