function buildVolumeOptions() {
    var subscriptionSelect = $("interest_subscription_plan");
    var values = volumes[ parseInt($F("siteKind"))];

    for (i = subscriptionSelect.options.length; --i >= 1; ) {
      subscriptionSelect.options[i].innerHTML = "Jusqu'à " + values[i - 1];
    }
  }

  function productChecked(product) {
    buildLines();
    if (undefined == $F(product)) {
      Element.hide(product.id + "Line");
    } else {
      Element.show(product.id + "Line");
    }
  }
  
  function nextStep() {
    if ($F('interest_subscription_mode_b_b') == undefined && $F('interest_subscription_mode_b_c') == undefined) {
      alert("Veuillez choisir l'activité de votre site");
      return;
    }
      if ($F('interest_subscription_plan') == "") {
          alert("Veuillez choisir le nombre de visite par mois");
          return;
      }
      if ($F('mode_1') == undefined && $F('mode_0') == undefined) {
          alert("Veuillez choisir le type d'abonnement");
          return
      }
      if ($F('suite') == undefined && $F('optimizer') == undefined &&
          $F('keyword_generator') == undefined && $F('click_quality') == undefined &&
          $F('web_ranking') == undefined && $F('universal_roi') == undefined) {
        alert("Veuillez choisir votre logiciel");
        return;
      }
    $('pageForm').submit();
  }

  function siteActivityClicked() {
    var kind = $('siteKind');
    kind.value =  $F("interest_subscription_mode_b_b") == undefined ? '0' : '1';
    buildVolumeOptions(); buildLines();
  }

  function volumeChanged() {
    var subscriptionSelect = $("interest_subscription_plan");
    var subscription = $F(subscriptionSelect);
    var subscriptionLimit = "0";
    for (i = subscriptionSelect.options.length; --i >= 0; ) {
      if (subscriptionSelect.options[i].value == subscription) {
        subscriptionLimit = subscriptionSelect.options[i].text;
      }
    }
    $('subscriptionVolume').value = "" + subscription;
    buildLines();
  }

  function subscriptionLengthChanged(duration) {
    $('subscriptionDuration').value = "" + duration;
    buildLines();

  }