function blocking(nr)
{
  if (document.getElementById)
  {
    current = (document.getElementById('submenu-' + nr).style.display == 'block') ? 'none' : 'block';
    document.getElementById('submenu-' + nr).style.display = current;
    if(current == 'block') {
      document.getElementById('menu-' + nr).className = 'menuactive';
    } else {
      document.getElementById('menu-' + nr).className = '';
    }
  }
  else if (document.all)
  {
    current = (document.all['submenu-' + nr].style.display == 'block') ? 'none' : 'block'
    document.all['submenu-' + nr].style.display = current;
    if(current == 'block') {
      document.all['menu-' + nr].className = 'menuactive';
    } else {
      document.all['menu-' + nr].className = '';
    }
  }
  else if (document.layers)
  {
    var i = parseInt('submenu-' + nr.substr('submenu-' + nr.length-1,1));
    var replacing = heights[i-1];
    if (shown[i])
    {
      shown[i] = false;
      replacing = -replacing;
      document.layers['submenu-' + nr].visibility = 'hide';
      document.layers['submenu-' + nr].top = safe;
    }
    else
    {
      shown[i] = true;
      document.layers['submenu-' + nr].visibility = 'show';
      var tempname = 'header' + i;
      document.layers['submenu-' + nr].top = document.layers[tempname].top + headerheight;
    }
    for (j=(i+1);j<=max;j++)
    {
      name1 = 'header' + j;
      document.layers[name1].top += replacing;
      if (shown[j])
      {
        name2 = 'number' + j;
        document.layers[name2].top += replacing;
      }
    }
  }
}

// Enrol menu popup
$(document).ready(function()
{
  
  // Handle click on button - show the popup
  $("#top-menu-enrol > a").click(function()
  {
    var button = $(this);
    var offset = button.offset();
    $("#enrol-popup")
      .css("top", offset.top + button.height() + 1)
      .css("left", offset.left + 1)
      .show();
    return false;
  });
  
  // Handle click on document - hide the popup
  $(document).click(function()
  {
    $("#enrol-popup").hide();
  });
  
  // Handle click on the popup - do nothing (i.e. don't hide it)
  $("#enrol-popup").click(function(event)
  {
    event.stopPropagation();
  });
  
});

// Enrol form: AS/A2
function enrol_asa2_update_week(i)
{
  var select = $("#week" + i + "_select select").get(0);
  var value = select.options[select.selectedIndex].value;
  if (value)
    $("#week" + i + "_details").show("fast");
  else
    $("#week" + i + "_details").hide("fast");
}

$(document).ready(function()
{
  if ($("#week1_select").length)
  {
    // n.b. I tried using a for loop, but the value inside the function was 4 by
    // the time it was run!
    $("#week1_select select").bind("change", function() { enrol_asa2_update_week(1); });
    $("#week2_select select").bind("change", function() { enrol_asa2_update_week(2); });
    $("#week3_select select").bind("change", function() { enrol_asa2_update_week(3); });
    enrol_asa2_update_week(1);
    enrol_asa2_update_week(2);
    enrol_asa2_update_week(3);
  }
});

// Enrol form: GCSE
function enrol_gcse_update_week(id)
{
  var checkbox = $("#" + id + "_checkbox input").get(0);
  if (checkbox.checked)
    $("#" + id + "_details").show("fast");
  else
    $("#" + id + "_details").hide("fast");
}

function enrol_gcse_update_allowed(half1, half2, full)
{
  var half1_checkbox = $("#" + half1 + "_checkbox input");
  var half2_checkbox = $("#" + half2 + "_checkbox input");
  var full_checkbox = $("#" + full + "_checkbox input");
  
  if (half1_checkbox.attr("checked") || half2_checkbox.attr("checked"))
  {
    full_checkbox.attr({checked: "", disabled: "disabled"});
  }
  else
  {
    full_checkbox.attr({disabled: ""});
  }
  
  if (full_checkbox.attr("checked"))
  {
    half1_checkbox.attr({checked: "", disabled: "disabled"});
    half2_checkbox.attr({checked: "", disabled: "disabled"});
  }
  else
  {
    half1_checkbox.attr({disabled: ""});
    half2_checkbox.attr({disabled: ""});
  }
}

$(document).ready(function()
{
  if ($("#week1_am_checkbox").length)
  {
    $("#week1_am_checkbox  input").bind("click", function() { enrol_gcse_update_week("week1_am");  enrol_gcse_update_allowed("week1_am", "week1_pm", "week1_day"); });
    $("#week1_pm_checkbox  input").bind("click", function() { enrol_gcse_update_week("week1_pm");  enrol_gcse_update_allowed("week1_am", "week1_pm", "week1_day"); });
    $("#week1_day_checkbox input").bind("click", function() { enrol_gcse_update_week("week1_day"); enrol_gcse_update_allowed("week1_am", "week1_pm", "week1_day"); });
    $("#week2_am_checkbox  input").bind("click", function() { enrol_gcse_update_week("week2_am");  enrol_gcse_update_allowed("week2_am", "week2_pm", "week2_day"); });
    $("#week2_pm_checkbox  input").bind("click", function() { enrol_gcse_update_week("week2_pm");  enrol_gcse_update_allowed("week2_am", "week2_pm", "week2_day"); });
    $("#week2_day_checkbox input").bind("click", function() { enrol_gcse_update_week("week2_day"); enrol_gcse_update_allowed("week2_am", "week2_pm", "week2_day"); });
    enrol_gcse_update_week("week1_am");
    enrol_gcse_update_week("week1_pm");
    enrol_gcse_update_week("week1_day");
    enrol_gcse_update_week("week2_am");
    enrol_gcse_update_week("week2_pm");
    enrol_gcse_update_week("week2_day");
    enrol_gcse_update_allowed("week1_am", "week1_pm", "week1_day");
    enrol_gcse_update_allowed("week2_am", "week2_pm", "week2_day");
  }
});

// Enrol form: Supplementary Tuition
function enrol_supplementary_update_subject(id)
{
  var text = $("#" + id + "_input input").val();
  if (text)
    $("#" + id + "_detail").show("fast");
  else
    $("#" + id + "_detail").hide("fast");
}

function enrol_supplementary_update_level(id)
{
  var select = $("#" + id + "_level_select select").get(0);
  var value = select.options[select.selectedIndex].text;
  if (value == "Other...")
    $("#" + id + "_level_detail").show("fast");
  else
    $("#" + id + "_level_detail").hide("fast");
}

$(document).ready(function()
{
  if ($(".supplementarytuitionform #subject1_input").length)
  {
    $("#subject1_input input").bind("change keyup mousemove blur", function() { enrol_supplementary_update_subject("subject1"); });
    $("#subject2_input input").bind("change keyup mousemove blur", function() { enrol_supplementary_update_subject("subject2"); });
    $("#subject3_input input").bind("change keyup mousemove blur", function() { enrol_supplementary_update_subject("subject3"); });
    $("#subject4_input input").bind("change keyup mousemove blur", function() { enrol_supplementary_update_subject("subject4"); });
    $("#subject1_level_select select").bind("change", function() { enrol_supplementary_update_level("subject1"); });
    $("#subject2_level_select select").bind("change", function() { enrol_supplementary_update_level("subject2"); });
    $("#subject3_level_select select").bind("change", function() { enrol_supplementary_update_level("subject3"); });
    $("#subject4_level_select select").bind("change", function() { enrol_supplementary_update_level("subject4"); });
    enrol_supplementary_update_subject("subject1");
    enrol_supplementary_update_subject("subject2");
    enrol_supplementary_update_subject("subject3");
    enrol_supplementary_update_subject("subject4");
    enrol_supplementary_update_level("subject1");
    enrol_supplementary_update_level("subject2");
    enrol_supplementary_update_level("subject3");
    enrol_supplementary_update_level("subject4");
  }
});