MyBot MapLoader

MyBot Pixel Place Map Loader
This script should not be not be installed directly. It is a library for other scripts to include with the meta directive // @require https://update.greasyfork.org/scripts/479128/1275793/MyBot%20MapLoader.js
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// ==UserScript==
// @name         MyBot MapLoader
// @description  MyBot Pixel Place Map Loader
// @version      1.6.2
// @author       SamaelWired
// @namespace    https://greasyfork.org/tr/users/976572
// @match        https://pixelplace.io/*
// @icon         https://www.google.com/s2/favicons?sz=64&domain=pixelplace.io
// @license      MIT
// @grant        none
// @run-at       document-start
// ==/UserScript==
(() => {
    const MyBot = window.MyBot || { modules: {} };
    window.MyBot = MyBot;
    if ('MapLoader' in MyBot.modules) return;

    const module = {};
    module.map = {};
    module.maps = {};

    module.args = {};
    module.config = ({ colors }) => Object.assign(module.args, { colors });

    module.callbacks = [];
    module.subscribe = func => module.callbacks.push(func);

    const Img = window.Image;
    window.Image = function () {
        const img = new Img(...arguments);

        Object.defineProperty(img, 'src', {
            enumerable: true,
            configurable: true,
            set(val) {
                this.setAttribute('src', val);
                if (!val.match(/canvas\/\d+\.png\?/)) return;
                const serverId = +val.match(/canvas\/(\d+)\.png\?/)[1];

                this.addEventListener('load', () => {
                    const canvas = document.createElement('canvas');
                    canvas.width = this.width;
                    canvas.height = this.height;

                    const ctx = canvas.getContext('2d');
                    ctx.drawImage(this, 0, 0);

                    const rgba = ctx.getImageData(0, 0, this.width, this.height).data;
                    const pixels = new Uint8Array(rgba.length >> 2);
                    for (let i = 0; i < rgba.length; i += 4) {
                        pixels[i >> 2] = module.args.colors.indexOf((rgba[i] << 16) + (rgba[i + 1] << 8) + rgba[i + 2]);
                    }

                    const { width, height } = this;
                    const map = {
                        pixels, width, height, serverId,
                        get(x, y) {
                            return this.pixels[x + y * this.width];
                        },
                        set(x, y, pixel) {
                            const offset = x + y * this.width;
                            if (this.pixels[offset] == null) return;
                            this.pixels[offset] = pixel;
                        }
                    };

                    if (!('serverId' in module.map)) Object.assign(module.map, map);
                    if (!MyBot.map) MyBot.map = map;

                    if (!MyBot.maps) MyBot.maps = {};
                    MyBot.maps[serverId] = map;
                    module.maps[serverId] = map;

                    module.callbacks.forEach(f => f(module, map));
                });
            }
        });

        return img;
    };
    Object.assign(Image, Img);
    for (let k in Img.prototype) try { Image.prototype[k] = Img.prototype[k]; } catch (e) {};

    MyBot.modules.MapLoader = module;
})();