// JavaScript Document
      promenna1 = new Image();
      promenna1.src = '/template/images/ikona_1_over.png';
      promenna2 = new Image();
      promenna2.src = '/template/images/ikona_2_over.png';
      promenna3 = new Image();
      promenna3.src = '/template/images/ikona_3_over.png';
      promenna4 = new Image();
      promenna4.src = '/template/images/ikona_4_over.png';
      promenna5 = new Image();
      promenna5.src = '/template/images/ikona_5_over.png';
      promenna6 = new Image();
      promenna6.src = '/template/images/ikona_6_over.png';
      promenna7 = new Image();
      promenna7.src = '/template/images/ikona_7_over.png';
      promenna8 = new Image();
      promenna8.src = '/template/images/ikona_8_over.png';
      promenna9 = new Image();
      promenna9.src = '/template/images/ikona_9_over.png';     
      promenna = new Image();
      promenna.src = '/template/images/ikona.gif'; 
      promenna11 = new Image();
      promenna11.src = '/template/images/submit_hover.jpg';
      function zpet(){
        document.getElementById('text-ikona').innerHTML='';
      }
      function zmena(text){
        document.getElementById('text-ikona').innerHTML=text;
      }
      function zobraz(id){
        document.getElementById('odkaz'+id).style.visibility='visible';
        document.getElementById('ikona_'+id).style.backgroundImage='url(/template/images/ikona.gif)';
      }
      function skryj(id){
        document.getElementById('odkaz'+id).style.visibility='hidden';
        document.getElementById('ikona_'+id).style.backgroundImage='url(/template/images/ikona_'+id+'.png)';
      }

      function submit_over(submit){
        document.getElementById(submit).style.backgroundImage='url(/template/images/submit_hover.jpg)';
      }
      function submit_out(submit){
        document.getElementById(submit).style.backgroundImage='url(/template/images/submit.jpg)';
      }
      
function is_email(str) {    
    if (str == "" || str.search("^.+@.+\\..+$") != -1)
        return true
    else
        return false;
}      

//reference      
function changeDateS(year){
  document.getElementById("year").value = year;
  document.getElementById("stranka").value = 0;
  document.forms[0].submit();
} 

//site      
function changeSite(site){
  document.getElementById("stranka").value = site;
  document.forms[0].submit();
}  

function changeCategory(){
  document.getElementById("stranka").value = 0;
  document.forms[0].submit();
}

//demand
function validateForm(){
  form = document.getElementById("send_demand");
  var textAlert = "";
  
  if (form.poznamka.value == ""){
    textAlert = "Informace o objednávce musí být vyplněna.\n";
  }
  
  if (form.lokalita.value == ""){
    textAlert = "Lokalita musí být vyplněna.\n";
  }
  
  if (form.email.value == ""){
    textAlert = "Email musí být vyplněn.\n";
  }else if (!is_email(form.email.value)){
    textAlert = "Email musí mít správný formát.\n";
  }
  
  if (form.jmeno.value == ""){
    textAlert = "Jméno musí být vyplněno.\n";
  }

  if (textAlert == ""){
    return true;
  }else{
    alert(textAlert);
    return false;
  }
}

function validateFormVacancies () {
  form = document.getElementById("send_vacancies");
  var textAlert = "";
  if (form.jmeno.value == ""){
    textAlert = "Jméno musí být vyplněno.\n";
  }
  
  if (form.email.value == ""){
    textAlert += "Email musí být vyplněn.\n";
  }else if (!is_email(form.email.value)){
    textAlert += "Email musí mít správný formát.\n";
  }

  if (textAlert == ""){
    return true;
  }else{
    alert(textAlert);
    return false;
  }

}