Как при переключения сезона сделать 1 серию сезона активной?

<script type="text/javascript">
var pos = 0;
var poz = 0;
var sea = null;
var width = 700;
var uvk = new Object();

(uvk = {
     init: function () {
            document.write("<div id=\"uber-vk-write\" align=\"center\">\
                            <ul id=\"uber-vk-season\"><li id=\"seasons\"></li></ul>\
                            <div id=\"uber-vk-player\"></div>\
                            <ul id=\"uber-vk-serial\"></ul>\
                            <a href=\"javascript://\" class=\"prev\" onclick=\"uvk.move(1);\">prev</a>\
                           <a href=\"javascript://\" class=\"next\" onclick=\"uvk.move(0);\">next</a>\
                           <a href=\"javascript://\" class=\"prev1\" onclick=\"uvk.move1(1);\">prev</a>\
                           <a href=\"javascript://\" class=\"next1\" onclick=\"uvk.move1(0);\">next</a>\
                           <div class=\"text_serii\">Выбирать серию</div>\
                           <\/div>");
    },
    player: function (a, b) {
        document.getElementById("uber-vk-player").innerHTML = "";
         var vk = document.createElement("iframe");
             vk.src = String(a);
             vk.width = "100%";
             vk.height = "460";
             vk.setAttribute("border","0");
             vk.setAttribute("frameborder", "0");
             document.getElementById("uber-vk-player").appendChild(vk);
         if (document.getElementById("uber-vk-serial")) {
              c = document.getElementById("uber-vk-serial").getElementsByTagName("span");
                for (var i=0; i<c.length; i++) {
                   c[i].removeAttribute("class")
                }
           }
     b.setAttribute("class", "active")
   },
   season : function (a, b) {
     if (document.getElementById("uber-vk-season")) {
     c = document.getElementById("uber-vk-season").getElementsByTagName("span");
             for (var i=0; i<c.length; i++) {
              document.getElementById("season"+i).style.display = "none";
            c[i].removeAttribute("class")
          }
          document.getElementById("season"+a).style.display = "";
          sea = a;
       }
     b.setAttribute("class", "active")
   },
   show: function (a, b) {
          for(var i=0; i<a.length; i++) {
                 document.getElementById("uber-vk-season").getElementsByTagName("li")[0].innerHTML += "<span onclick=\"uvk.season("+i+", this)\">"+a[i]+"</span>";
                 document.getElementById("uber-vk-serial").innerHTML += "<li id=\"season" + i + "\" style=\"display:none;\"></li>";
                 }
                 for(var i=0; i<a.length; i++) {
                 for(var j=0; j<b[i].length; j++) {
                 document.getElementById("season" + i).innerHTML += "<span onclick=\"uvk.player('"+b[i][j]+"', this);\">" + (j+1) + "</span>";
             }
       }
       document.getElementById("uber-vk-season").getElementsByTagName("span")[0].setAttribute("class", "active");
       document.getElementById("uber-vk-season").getElementsByTagName("span")[0].click();
       document.getElementById("season0").getElementsByTagName("span")[0].click();
       document.getElementById("season0").style.display = "";
      
   },
   move: function (d) {
           var a, b;
        var butt = document.getElementById("seasons");
        var widt = butt.offsetWidth;
        var left = butt.offsetLeft;
        if (d == 0) {
            clearTimeout(a);
            b = setInterval(function () {
              pos = pos - 10;
          if (pos >= (left-width) && pos >= -(widt-width)) {
              butt.style.left = pos + "px";
            } else clearTimeout(b);
            }, 15);
        }
        
        if (d == 1) {
            clearTimeout(b);
            b = setInterval(function () {
              pos = pos + 10;
          if (pos <= (left+width) && pos <= 0) {
              butt.style.left = pos + "px";
            } else clearTimeout(b);
            }, 15);
        }
   },
   move1: function (d) {
           var a, b;
        var butt = document.getElementById("season" + sea);
        var widt = butt.offsetWidth;
        var left = butt.offsetLeft;

        if (d == 0) {
            clearTimeout(a);
            b = setInterval(function () {
              poz = poz - 10;
          if (poz >= (left-width) && poz >= -(widt-width)) {
              butt.style.left = poz + "px";
            } else clearTimeout(b);
            }, 10);
        }
        
        if (d == 1) {
            clearTimeout(b);
            b = setInterval(function () {
              poz = poz + 10;
          if (poz <= (left+width) && poz <= 0) {
              butt.style.left = poz + "px";
            } else clearTimeout(b);
            }, 10);
        }
    }
});
</script>