function CheckElement(element){
  if(element=="paym"){
    var ind = document.getElementById("paym").selectedIndex;
    var data_std  = document.getElementById("paym_det_std");
    var data_rdc  = document.getElementById("paym_det_rdc");
    
    if(ind==0){
      data_std.style.display = "";
      data_rdc.style.display = "none";
    }
    else{
      data_rdc.style.display = "";
      data_std.style.display = "none";
    }
  }
  else if(element=="part"){
    var ind = document.getElementById("participation").selectedIndex;
    var descr_ind = document.getElementById("descr").selectedIndex;
    var data = document.getElementById("part_data");
    var descr_main = document.getElementById("descr_main");
    var descr_data = document.getElementById("descr_data");
    
    if(ind==0){
      data.style.display = "none";
      descr_main.style.display = "none";
      descr_data.style.display = "none";
    }
    else{
      data.style.display = "";
      descr_main.style.display = "";

      if(descr_ind!=0){
        descr_data.style.display = "";
      }
    }

  }
  else{
    if(element=="invoice"){
      var ind = document.getElementById("invoice").selectedIndex;
      var data  = document.getElementById("inv_data");
    }
    else if(element=="note"){
      var ind = document.getElementById("note").selectedIndex;
      var data  = document.getElementById("note_data");
    }
    else if(element=="descr"){
      var ind = document.getElementById("descr").selectedIndex;
      var data  = document.getElementById("descr_data");
    }
    
    if(ind==0) data.style.display = "none";
    else data.style.display = "";
  }


  return 0;
}

////////////
function SubmitForm(form_type){
  var regexp  = /^[\s\t\r\n]*$/i,
    rexp_num  = /[0-9]+/i,
    rexp_mail = /^[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,4}$/i;

  if(form_type=='logform'){
    var log   = document.getElementById('log').value;
    var pass  = document.getElementById('pass').value;

    if(log.length<4 || pass.length<4 || regexp.test(log) || regexp.test(pass)){
      alert('Proszę podać poprawny login i hasło!');
      return false;
    }
    else{
      HideLogBtn();
      document.getElementById('ref').value = "login";
      return true;
    }
  }
  else if(form_type=="rejestracja"){
  	var fname     = document.getElementById("pers_fname"),
      lname       = document.getElementById("pers_lname"),
      pers_mail   = document.getElementById("pers_mail"),
      pers_phone  = document.getElementById("pers_phone"),
      pers_mobile = document.getElementById("pers_mobile"),
      pers_fax    = document.getElementById("pers_fax"),
      form_agree  = document.getElementById("form_agree"),
      cont_str = pers_mail.value + pers_phone.value + pers_mobile.value + pers_fax.value;

    if(regexp.test(fname.value) || rexp_num.test(fname.value)){
      alert("Prosimy o podanie swojego imienia.");
      fname.focus();
      return false;
    }
    else if(regexp.test(lname.value) || rexp_num.test(lname.value)){
      alert("Prosimy o podanie swojego nazwiska.");
      lname.focus();
      return false;
    }
    else if(regexp.test(cont_str)){
      alert("Prosimy o podanie co najmniej jednego z pól danych kontaktowych.");
      pers_mail.focus();
      return false;
    }
    else if(!regexp.test(pers_mail.value) && !rexp_mail.test(pers_mail.value)){
      alert("Prosimy o podanie poprawnego adresu mailowego.");
      pers_mail.focus();
      return false;
    }
    else if(form_agree.checked == false || form_agree.checked == "no"){
      alert("Prosimy o wyrażenie zgody na przetwarzanie danych osobowych.");
      return false;
    }

    document.getElementById(form_type).action = "index.php?action=kongres&subac=zarejestrowano";
    document.getElementById(form_type).submit();
  }
  else if(form_type=="newsletter"){
    var mail = document.getElementById("e_mail");

    if(!rexp_mail.test(mail.value)){
      alert("Prosimy o podanie poprawnego adresu mailowego.");
      mail.focus();
      return false;
    }
    else{
      document.getElementById(form_type).action = "index.php?action=newsletter&subac=zarejestrowano";
      document.getElementById(form_type).submit();
    }
  }
  else if(form_type=="add_content" || form_type=="edit_content"){
    var title = document.getElementById("title");
    var content = document.getElementById("content");

    if(regexp.test(title.value)){
      alert("Proszę podać tytuł");
      title.focus();
      return false;
    }
    else{
      if(form_type=="add_content") document.getElementById(form_type).action = "index.php?action=cont&subac=add";
      else if(form_type=="edit_content") document.getElementById(form_type).action = "index.php?action=cont&subac=edit_cont";
      document.getElementById(form_type).submit();
    }
  }
  else if(form_type=="add_links" || form_type=="edit_links"){
    var alias = document.getElementById("alias");
    var id_cont = document.getElementById("id_cont");

    if(regexp.test(alias.value)){
      alert("Proszę podać alias linku");
      alias.focus();
      return false;
    }
    else if(regexp.test(id_cont.value)){
      alert("Proszę podać ID treści");
      id_cont.focus();
      return false;
    }
    else{
      if(form_type=="add_links") document.getElementById(form_type).action = "index.php?action=links&subac=add";
      else if(form_type=="edit_links") document.getElementById(form_type).action = "index.php?action=links&subac=edit_links";
      document.getElementById(form_type).submit();
    }
  }
  else if(form_type=="change_selection"){
    form = document.getElementById(form_type);
    form.submit();
    return true;
  }

  return false;
}

function HideLogBtn(){
  document.getElementById('log_btn').style.display = "none";
  document.getElementById('log_txt').style.display = "inline";
}

//
function ShowOverlay(){
	var thediv = document.getElementById('displaybox');
	if(thediv.style.display == "none"){
		thediv.style.display = "";
		thediv.innerHTML = "<table width='100%' height='100%'><tr><td align='center' valign='middle' width='100%' height='100%' style='border:1px black solid; padding:25px'><img src='images/ajax-load-main.gif' width='85px'></td></tr></table>";
	}
  else{
		//thediv.style.display = "none";
		//thediv.innerHTML = '';
	}
	return false;
}

//maxlength
function MaxLen(id){
  var elem = document.getElementById(id);
  
  var maxlength = elem.getAttribute ? parseInt(elem.getAttribute("maxlength")) : "";
  if(elem.getAttribute && elem.value.length>maxlength){
    elem.value = elem.value.substring(0, maxlength);
  }
}