function openForm() {
  var main_div_height = document.getElementById('main').offsetHeight;
  var main_div_width = document.getElementById('main').offsetWidth;
  
  document.getElementById('send_form_bg').style.height = main_div_height + 'px';
  document.getElementById('send_form_bg').style.width = '100%';
  
  $('#send_form_bg').fadeIn('fast',function() {
      $('#form_holder').slideDown('fast');
  });
}

function closeForm() {  
  $('#form_holder').slideUp('fast',function() {
      document.getElementById('u_name').value = '';
	  document.getElementById('u_mail').value = '';
	  document.getElementById('u_message').value = '';
	  document.getElementById('u_id').value = '';
	  $('#error_send').slideUp('fast');
	  $('#success_send').slideUp('fast');
      $('#send_form_bg').fadeOut('fast');
  });
}

function sendMessage(obj) {
  var u_name = obj.u_name.value;
  var u_mail = obj.u_mail.value;
  var u_message = obj.u_message.value;
  var u_id = obj.u_id.value;
  
  if(u_name!='' && u_mail!='' && u_message!='' && u_id!='') {
      $('#error_send').slideUp('fast',function() {
	      sendMessageAjax(u_name,u_mail,u_message,u_id);
	  });      
  }
  else {
      $('#error_send').html('Все поля обязательны для заполнения.');
      $('#error_send').slideDown('fast');
  }
}

function sendMessageAjax(u_name,u_mail,u_message,u_id) {
    var b = new Date();
    $.ajax({    
    url: '/ajax/sendMessage.php',
	data: 'u_name='+u_name+'&u_mail='+u_mail+'&u_message='+u_message+'&u_id='+u_id+'&date='+b.toLocaleString(),
    dataType: 'xml',
    type: 'POST',	
    success: function (xml) {
        $(xml).find('data').each(function(){
		    if($(this).find('errors_count').text()>0) {
			    $('#error_send').html($(this).find('error_message').text());
				$('#error_send').slideDown('fast');		
			}
			else {
			    $('#success_send').html('Сообщение успешно отправлено.');
				$('#success_send').slideDown('fast',function() {
				    var close_timer = window.setTimeout(function() {closeForm();}, 1700);				    
				});			    
			}
        });		
        },
	error: function(){
        alert('Man! You have a problem here!');
        },
    beforeSend: function(){
        // Handle the beforeSend event
        },
    complete: function(){	    
        // Handle the complete event
        }	
    });    
}