// ==UserScript==
// @name        YouTube to Invidious
// @author      OdinBrood, Jesús E.
// @namespace   InvidiousRedirect
// @description Scan page for Youtube embeds and urls and replace with Invidious.
// @homepageURL https://libregit.org/heckyel/book/src/branch/master/scripts-greasemonkey
// @include     *
// @exclude     /^http(s|)://(www[.]|)invidio[.]us/.*$/
// @exclude     /^http(s|)://(www[.]|proxy[.]|)invidious[.]snopyta[.]org/.*$/
// @exclude     /^http(s|)://(www[.]|)vid[.]wxzm[.]sx/.*$/
// @exclude     /^http(s|)://(www[.]|)invidious[.]kabi[.]tk/.*$/
// @exclude     /^http(s|)://(www[.]|)invidiou[.]sh/.*$/
// @exclude     /^http(s|)://(www[.]|)invidious[.]enkirton[.]net/.*$/
// @exclude     /^http(s|)://(www[.]|)tube[.]poal[.]co/.*$/
// @exclude     /^http(s|)://(www[.]|)invidious[.]13ad[.]de/.*$/
// @grant       GM_xmlhttpRequest
// @version     8.4.5
// @license     GPL version 3 or any later version::: https://www.gnu.org/licenses/gpl-3.0.html
// ==/UserScript==
/* jshint esversion: 6 */

// set you favorite Invidious instance! (https://github.com/omarroth/invidious/wiki/Invidious-Instances)
let instance = 'invidio.us';

// Console Style - Debug
let consoleCSS = 'background: #000; color: #00FF00; padding: 0px 7px; border: 1px solid #00FF00; line-height: 16px;';

// change script options, default values recommended
let a=1; //set to 0 to force autoplay off, set to 1 to keep embed's value [default 1]
let b=1; //set to 0 to not replace all youtube links to Invidious [default 1]
let c=1; //set to 0 to disable DASH playback (beta feature) [default 1]
let d=1; //set to 0 to disable Invidious proxy [default 1]
let e=1; //set to 0 to disable bypass of url shorteners [default 1]

let ytdomains=new RegExp(/http(s|)\:\/\/(m[.]|i[.]|www[.]|img[.]|)(youtu(|be|be-nocookie)|.*ytimg)[.](com|be)\/.*/);
let shorteners=new RegExp(/^http(s|):\/\/(bit.ly|goo.gl|tinyurl.com|t.co|ow.ly|is.gd|buff.ly|deck.ly|su.pr|lnk.co|fur.ly|moourl.com|)\/.*/);
let params=new RegExp(/^(autoplay|channel|v|playlist|list)$/);
let current=window.location.href.match(ytdomains)===null;
let frames,thumbs,links,skip;

if(current){
    frames=Array.prototype.slice.call(document.getElementsByTagName('iframe')).filter(ytel);
    thumbs=Array.prototype.slice.call(document.getElementsByTagName('img')).filter(ytel);
    if(b==1)links=Array.prototype.slice.call(document.getElementsByTagName('a')).filter(ythref);
    if(frames.length>0)embed();
    if(thumbs.length>0)thumb();
    if(links.length>0)link();
    statuscheck();
}else{
    let title=Array.prototype.slice.call(document.getElementsByTagName('h1'));
    addbtn();
}

let observer=new MutationObserver(function(mutations){
    mutations.forEach(function(mutation){
        if(current){
            frames=Array.prototype.slice.call(mutation.target.getElementsByTagName('iframe')).filter(ytel);
            thumbs=Array.prototype.slice.call(mutation.target.getElementsByTagName('img')).filter(ytel);
            if(frames.length>0)embed();
            if(thumbs.length>0)thumb();
            if(b==1){
                links=Array.prototype.slice.call(mutation.target.getElementsByTagName('a')).filter(ythref);
                if(links.length>0)link();
            }
        }else{
            skip=Array.prototype.slice.call(mutation.target.getElementsByClassName('skipinv'));
            if(skip<1){
                title=Array.prototype.slice.call(mutation.target.getElementsByTagName('h1'));
                addbtn();
            }
        }
    });
});
observer.observe(document.body,{childList:true,subtree:true});

function embed(){
    for(let i=0;i<frames.length;i++){
        frames[i].style.backgroundColor='rgba(35,35,35,1)';
        frames[i].style.backgroundRepeat='no-repeat';
        frames[i].style.backgroundPosition='center center';
        frames[i].style.backgroundSize='auto';
        for(let j=0;j<frames[i].attributes.length;j++) {
            if(frames[i].attributes[j].value.match(ytdomains)){
                let url=new URL(frames[i].attributes[j].value);
                if(!url.hostname.match(/youtube/)){
                    url=new URL(decodeURIComponent(url.href).match(ytdomains)[0]);
                    url.searchParams.set('autoplay',0);
                }
                for(let key of url.searchParams.keys()){
                    if(!(key.match(params)))url.searchParams.delete(key);
                }
                url.hostname=instance;
                if(a==1){
                    if(!url.searchParams.has('autoplay')||url.searchParams.get('autoplay')==='')url.searchParams.set('autoplay',0);
                }else{
                    url.searchParams.set('autoplay',0);
                }
                if(c==1)url.searchParams.set('quality','dash');
                if(d==1)url.searchParams.set('local',true);
                frames[i].setAttribute(frames[i].attributes[j].name,url);
            }
        }
    }
}

function thumb(){
    for(let i=0;i<thumbs.length;i++){
        let url=new URL(thumbs[i].src.match(ytdomains)[0]);
        url.hostname=instance;
        thumbs[i].src=url;
    }
}

function link(){
    for(let i=0;i<links.length;i++){
        let url=new URL(links[i].href.match(ytdomains)[0]);
        url.hostname=instance;
        links[i].href=url;
    }
}

function addbtn(){
    for(let i=0;i<title.length;i++){
        let btn=document.createElement('a');
        btn.innerHTML='<h2>Watch on '+instance+'</h2>';
        btn.href='javascript:void(0)';
        btn.onclick=function(){redir();};
        btn.className='skipinv';
        title[i].parentNode.appendChild(btn);
    }
}

function redir(){
    let url=new URL(window.location.href);
    url.hostname=instance;
    location.href=url;
}

function unshorten(long,short){
    frames=Array.prototype.slice.call(document.getElementsByTagName('iframe'));
    for(let k=0;k<frames.length;k++){
        for(let l=0;l<frames[k].attributes.length;l++) {
            if(frames[k].attributes[l].value==long){
                frames[k].attributes[l].value=short;
                frames=[frames[k]];
                embed();
                return;
            }
        }
    }
}

function ytel(el){
    for(let i=0;i<el.attributes.length;i++){
        let val=el.attributes[i].value;
        if(val.substring(0,2)=='//')val='https:'+val;
        try{val=decodeURIComponent(val);}catch(e){}
        if(val.match(shorteners)&&e==1){
            let long=el.attributes[i].value=val;
            GM_xmlhttpRequest({
                method:'GET',url:long,onload:function(response){
                    let short=response.finalUrl;
                    if(short.match(ytdomains))unshorten(long,short);
                }
            });
        }
        if(val.match(ytdomains)){
            el.attributes[i].value=val;
            return true;
        }
    }
}

function ythref(el){
    return(decodeURIComponent(el.href).match(ytdomains));
}

function statuscheck(){
    // Console Feedback
    console.log("%cUSERSCRIPT | " + GM_info.script.name + " " + GM_info.script.version + " | successfully initialized", consoleCSS);
}