function setFields()
{
  var radio_buttons       = $$( 'input.amount_radio' );
  var radio_button_other  = $( 'amount_radio_other' );
  var amount_text         = $( 'amount_text' );
  var amount              = $( 'amount' );
  var SHASign             = $( 'SHASign' );

  // set amount
  if ( radio_button_other.checked == true )
  {
    amount.value = ( amount_text.value * 100 );
  }
  else
  {
    // is one of the radio buttons checked?
    radio_buttons.each( function( radio_button )
    {
      if ( radio_button.checked == true )
      {
        amount.value = radio_button.value;
      }
    } );
  }

  if ( ( amount.value != '' ) && ( amount.value != '0' ) && ( amount.value != 'NaN' ) )
  {
    return getOrderID();
  }
}

function getOrderID()
{
  var firstname     = $( 'firstname' );
  var lastname      = $( 'lastname' );
  var EMAIL         = $( 'EMAIL' );
  var ownerZIP      = $( 'ownerZIP' )
  var ownertown     = $( 'ownertown' );
  var orderID       = $( 'orderID' );
  var amount        = $( 'amount' );

  if ( ( orderID.value == '' ) || ( orderID.value == '0' ) || ( orderID.value == 'NaN' ) )
  {
    new Ajax.Request( '/spende.php', {
      parameters: 'firstname=' + firstname.value + '&lastname=' + lastname.value + '&EMAIL=' + EMAIL.value + '&ownerZIP=' + ownerZIP.value + '&ownertown=' + ownertown.value + '&amount=' + amount.value,
      onSuccess: setOrderId,
      onComplete: getSHASign
    } );
  }
  else
  {
    getSHASign();
  }
}

function setOrderId( ajaxRequest )
{
  var orderID = $( 'orderID' );

  orderID.value = ajaxRequest.responseText;
}

function getSHASign()
{
  var orderID = $( 'orderID' );
  var amount  = $( 'amount' );

  new Ajax.Request( '/shaSign.php',
  {
    parameters: 'orderID=' + orderID.value + '&amount=' + amount.value + '&currency=CHF&PSPID=awmspenden',
    onSuccess: setSHASign,
    onComplete: enableSubmit
  } );
}

function setSHASign( ajaxRequest )
{
  var SHASign = $( 'SHASign' );

  SHASign.value = ajaxRequest.responseText;
}

function checkRadioButton( element_id )
{
  var element = $( element_id );

  element.checked = true;
}

function enableSubmit()
{
  var spenden_submit  = $( 'spenden_submit' );

  spenden_submit.disabled = false;
}

function disableSubmit()
{
  var spenden_submit  = $( 'spenden_submit' );

  spenden_submit.disabled = true;
}

function validateSubmit()
{
  var orderID         = $( 'orderID' );
  var amount          = $( 'amount' );

  if ( ( orderID.value != '' ) && ( orderID.value != '0' ) && ( orderID.value != 'NaN' ) && ( amount.value != '' ) && ( amount.value != '0' ) && ( amount.value != 'NaN' ) )
  {
    return true;
  }
  else
  {
    alert( 'Bitte einen Betrag auswählen oder eingeben' );
    return false;
  }
}

function setCN()
{
  var firstname     = $( 'firstname' );
  var lastname      = $( 'lastname' );
  var CN            = $( 'CN' );
  var customername  = new String();

  customername = firstname.value + ' ' + lastname.value;
  CN.value = customername.strip();
}