Userscript to play files in external media player

play_external.user.js

// ==UserScript==
// @name       Play in external player
// @namespace  http://wol.ph/
// @version    1.0
// @grant          GM_getValue
// @grant          GM_openInTab
// @grant          GM_registerMenuCommand
// @grant          GM_setValue
// @include      http://*
// @include      https://*
// @copyright  2015, Wolph
// ==/UserScript==


function getDomains(){
    return GM_getValue('domains', '');
}

function setDomains(domains){
    if(domains !== null)return GM_setValue('domains', domains);
}

function getPlayerPrefix(){
    return GM_getValue('player_prefix', 'mpv://');
}

function setPlayerPrefix(prefix){
    if(domains !== null)return GM_setValue('player_prefix', prefix);
}

function getPlayerPostfix(){
    return GM_getValue('player_postfix', '');
}

function setPlayerPostfix(postfix){
    if(domains !== null)return GM_setValue('player_postfix', postfix);
}

function configureDomains(){
    setDomains(prompt("Enabled domains (regular expression, separate by '|'): ", getDomains()));
}

function configurePlayer(){
    setPlayerPrefix(prompt("Set the player prefix: ", getPlayerPrefix()));
    setPlayerPostfix(prompt("Set the player postfix: ", getPlayerPostfix()));
}

GM_registerMenuCommand("External player domains", configureDomains);
GM_registerMenuCommand("External player", configurePlayer);

if(document.location.hostname.match(getDomains())){
    window.setTimeout(function(){
        try{
        $('.jwplayer').after(
            '<a href="' + getPlayerPrefix() + __fileurl
            + getPlayerPostfix() + '">Play local</a>');
        }catch(e){
        };
    }, 500);
}