video.js

$(document).ready(function(e) {
    $("#video-next, #video-prev").click(function(event) {
        var index = (function(i){return (i < 0) ? 6 : (i > 6) ? 0 : i})($("#video-player").data("index") + $(this).data("dir"));
        $("#video-player").attr({'data-index': index, 'src': (["https://youtube.com/embed/XFTR70j_8u0","https://youtube.com/embed/Eb_wyy_PaR0","https://youtube.com/embed/1C_n9RryuV0","https://youtube.com/embed/IsXmPVvXIjA","https://youtube.com/embed/eAoVwCSo_Qo","https://youtube.com/embed/KzuMTaiAr_0","https://youtube.com/embed/BZgtJcgfU4k"])[index]});
        event.preventDefault();
    });
});