Go to next image

next-image.js

window.location = makeBumpedUrl();

function makeBumpedUrl() {
    const imageNumber = getImageNumberInUrl();
    const newImageNumber = bumpTrailingNumber(imageNumber);
    return window.location.href.replace(imageNumber, newImageNumber);
}

function getImagePathInUrl() {
    const urlComponents = window.location.href.split("/");
    const imagePath = urlComponents[urlComponents.length-1];
    return imagePath.split(".")[0];
}

function bumpTrailingNumber(s) {
    let trailingZeros = numOfTrailingZeros(s);
    if (doesBumpAddDigit(s))
        trailingZeros--;
    return pad(Number(s)+1, trailingZeros);
}

function doesBumpAddDigit(s) {
    const num = Number(s);
    const bumped = num + 1;
    return String(num).length !== String(bumped).length;
}

function numOfTrailingZeros(s) {
    const regex = /^0*/;
    const matches = s.match(regex);
    return matches[0].length;
}

function pad(num, zeros) {
    let s = num.toString();
    for (let i = 0; i < zeros; i++)
        s = "0" + s;
    return s;
}