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MPP BG Sync

Syncs backgrounds via chat.

You will need to install an extension such as Tampermonkey, Greasemonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Userscripts to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install a user script manager extension to install this script.

(У мене вже є менеджер скриптів, дайте мені встановити його!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

(I already have a user style manager, let me install it!)

// ==UserScript==
// @name         MPP BG Sync
// @namespace    http://tampermonkey.net/
// @version      2.1
// @description  Syncs backgrounds via chat.
// @author       MrButtersLot
// @match        https://www.multiplayerpiano.net/*
// @match        https://multiplayerpiano.net/*
// @grant        none
// ==/UserScript==

(function() {
    'use strict';

    const mainLayer = document.createElement('div');
    mainLayer.style = "position:fixed; top:0; left:0; width:100vw; height:100vh; pointer-events:none; z-index:-1; background:black; background-repeat:no-repeat; background-position:center; background-size:contain;";
    document.body.appendChild(mainLayer);

    const videoLayer = document.createElement('video');
    videoLayer.style = "position:fixed; top:0; left:0; width:100vw; height:100vh; object-fit:contain; z-index:-2; background:black; display:none;";
    videoLayer.loop = true; videoLayer.muted = true; videoLayer.autoplay = true;
    document.body.appendChild(videoLayer);

    const showMessage = () => {
        const msg = document.createElement('div');
        msg.innerText = "say !bg [imgur link] to change background globally";
        msg.style = "position:fixed; top:40%; left:50%; transform:translate(-50%, -50%); background:rgba(0,0,0,0.8); color:#2ecc71; padding:15px 30px; border-radius:10px; font-family:sans-serif; font-weight:bold; font-size:1.2em; z-index:10001; pointer-events:none; border:2px solid #2ecc71; transition:opacity 1s ease-out;";
        document.body.appendChild(msg);

        setTimeout(() => {
            msg.style.opacity = "0";
            setTimeout(() => msg.remove(), 1000);
        }, 3000);
    };

    const apply = (url) => {
        if (!url || !url.includes('i.imgur.com')) return;
        const isVid = url.toLowerCase().endsWith('.mp4');
        
        if (isVid) {
            document.body.style.backgroundImage = "none";
            mainLayer.style.backgroundImage = "none";
            if (videoLayer.src !== url) {
                videoLayer.src = url;
                videoLayer.style.display = "block";
                videoLayer.play().catch(()=>{});
            }
        } else {
            videoLayer.style.display = "none";
            videoLayer.pause();
            const css = `url(${url})`;
            document.body.style.background = `black ${css} no-repeat center center fixed`;
            document.body.style.backgroundSize = "contain";
            mainLayer.style.backgroundImage = css;
        }
    };

    const checkHistory = () => {
        setTimeout(() => {
            const list = document.querySelectorAll('#chat li');
            for (let i = list.length - 1; i >= 0; i--) {
                const txt = list[i].innerText;
                const hit = txt.match(/!bg\s+(https?:\/\/i\.imgur\.com\/\S+)/);
                if (hit) {
                    apply(hit[1]);
                    break;
                }
            }
        }, 500);
    };

    const start = () => {
        if (window.MPP && window.MPP.client) {
            window.MPP.client.on('a', (m) => {
                const t = (m.a || "").trim();
                if (t.startsWith('!bg ')) apply(t.split(' ')[1]);
            });
            window.MPP.client.on('ch', checkHistory);
            checkHistory();
            showMessage();
        } else {
            setTimeout(start, 500);
        }
    };

    const btn = document.createElement('button');
    btn.innerText = "BRING TO FRONT";
    btn.style = "position:fixed; top:10px; right:10px; z-index:10000; background:#e67e22; color:white; border:none; padding:6px 12px; cursor:pointer; font-weight:bold; border-radius:4px; opacity:0.6; transition:0.3s;";
    
    let active = false;
    btn.onclick = () => {
        active = !active;
        mainLayer.style.zIndex = active ? "9998" : "-1";
        videoLayer.style.zIndex = active ? "9997" : "-2";
        mainLayer.style.pointerEvents = active ? "all" : "none";
        btn.innerText = active ? "SEND TO BACK" : "BRING TO FRONT";
        btn.style.background = active ? "#95a5a6" : "#e67e22";
    };
    
    document.body.appendChild(btn);
    start();
})();