function createSelectBox(name, data_list, default_value) {
  var obj = document.createElement('select');
  obj.setAttribute('name', name);
  counter = 0;

  for (value in data_list) {
    var opt = document.createElement('option');
    opt.appendChild(document.createTextNode(data_list[value]));
    opt.value = value;
    obj.appendChild(opt);

    if (value == default_value) {
      obj.selectedIndex = counter;
    }
    counter++;
  }
  return obj;
}

function yearChange(year_value) {
  var form = document.getElementById('search_form');

  if (!year_value) {
    var year_value = form.childNodes[1].options.item(form.childNodes[1].selectedIndex).value;

  } else {
    for (var i = 0; i < form.childNodes[1].length; i++) {
      if (form.childNodes[1].options.item(i).value == year_value) {
        form.childNodes[1].selectedIndex = i;
        break;
      }
    }
  }
  var bumon_value = form.childNodes[3].options.item(form.childNodes[3].selectedIndex).value;

  form.replaceChild(createBumonSelectBox(year_value, bumon_value), form.childNodes[3]);
}

function getPost(year_value, bumon_value) {
  var form = document.getElementById('search_form');
  form.replaceChild(createBumonSelectBox(year_value, bumon_value), form.childNodes[3]);
}

function bumonChange() {
  var form = document.getElementById('search_form');
}

function createBumonSelectBox(year, default_value) {
  var data_list = new Array();
  data_list['all_all'] = 'すべての部門';

  if (year == 'all') {
    for (var key in bumon_list) {
      data_list[key+'_all'] = bumon_list[key];
    }

  } else {
    var prev_bumon = null;

    for (var bumon_value in year_category_list[year]) {
      cur_bumon = bumon_value.substring(0, bumon_value.indexOf('_'));
      cur_category = bumon_value.substring(bumon_value.indexOf('_') + 1);

      if (cur_bumon != prev_bumon) {
        data_list[cur_bumon+'_all'] = bumon_list[cur_bumon];
        prev_bumon = cur_bumon;
      }
      data_list[bumon_value] = category_list[cur_category];
    }
  }

  return createSelectBox('bumon', data_list, default_value)
}