Reverse-engineered script injected by HakuNeko to un-scramble the links list based on the first image link.

hakuneko_postload_parser.js

new Promise((resolve, reject) => {
    
    function getImage() {
        resolve( [...this.document.querySelectorAll("div#image a img")].map(el => el.src) );
    }

    function getImageFromHtml() {
        console.log("green yoda dongers")
        let pageCode = new this.URL(this.document.querySelector("div.container select#pages option").dataset.img).pathname.split('.').shift().split('');
        let imageCode = new this.URL(this.document.querySelector("#image a img").src).pathname.split('.').shift().split('');
        let finalCode = {};
        for (let i = 0x0; i < pageCode.length; i++) {
            finalCode[pageCode[i]] = imageCode[i];
            console.log(`finalCode[${pageCode[i]}] = ${imageCode[i]}`)
        }
        let pagesList = this.document.querySelectorAll("div.container select#pages option");
        pagesList = [...pagesList].map(el => {
            let finalURL = new this.URL(el.dataset.img);
            let urlFields = finalURL.pathname.split('.');
            urlFields[0] = urlFields[0].split('').map(f => finalCode[f]).join('');
            finalURL.pathname = urlFields.join('.');
            return finalURL.href;
        });
        console.log(pagesList)
        resolve(pagesList);
    }

    function getCanvas() {
        reject(new Error("Single-page with scrambled images is not yet supported!"));
    }

    function getCanvasFromHtml() {
        let pagesListItems = [...this.document.querySelectorAll("div.container select#pages option")];
        let pagesURLs = pagesListItems.map(el => new this.URL(el.value, window.location.href).href);
        resolve(pagesURLs);
    }

    this.setTimeout(() => {
        try {
            let imgOut = this.document.querySelector("div#image a img") && !![];
            let canvasOut = this.document.querySelector("div#image a canvas") && !![];
            let isHtml = this.document.querySelector("div#image").dataset.nextLink.endsWith(".html");
            let isnotHtml = !isHtml;
            switch (!![]) {
                case (isnotHtml && imgOut):
                    return getImage();
                case (isHtml && imgOut):
                    return getImageFromHtml();
                case (isnotHtml && canvasOut):
                    return getCanvas();
                case (isHtml && canvasOut):
                    return getCanvasFromHtml();
                default:
                    reject(new Error("Unknown condition could not be processed!"));
            }
        } catch (err) {
            reject(err);
        }
    }, 2500);
});

console.log("hakuneko_uo loaded")