//common functions
function classChange(mytarget, myclass){
	if (document.getElementById(mytarget)){
		document.getElementById(mytarget).className = myclass;
	}
}

/** change class of itself, it doesn't matter of element ID
 *@param elem - element
 *param newclass - required class for change
 */
function classChangeSelf(elem, newclass){
  elem.className = newclass;
}

/** delete value of element ... input
 *@param elem - element
 *@param str - string
  */
function delValue(elem, str){
  if(elem.value == str) elem.value = "";
  return;
}

function switchImg(num, imgname) {
  document.getElementById(imgname).src = img[num].src;
}

function changeLocation(sel, loc){
  var order = sel[sel.selectedIndex].value;
  loc = loc + '' + order;
  location.href = loc;
  return;
}

function limitText(limitField, limitNum){
  if(limitField.value.length > limitNum){
    limitField.value = limitField.value.substring(0, limitNum);
  }
}

function check_form_video_upload(mode){

  if(!mode){
    //normal user - upload-video.php
    var nazev = document.getElementById('video_title');
    var popis = document.getElementById('video_description');
    var keywords = document.getElementById('video_keywords');
    var file = document.getElementById('video_file');
    var pic = "normal_user";
    var ftp = null;
  }else{
    //admin
    var nazev = document.getElementById('fav_name');
    var popis = document.getElementById('fav_short_text');
    var keywords = document.getElementById('fav_keywords');
    var file = document.getElementById('fav_flv');
    var pic = document.getElementById('fav_image');
    var ftp = document.getElementById('fav_ftp');
  }
  
  var check_flv = 1;
  var check_img = 1;
  
  //admi osetreni - nahrati videofilu FLv pres FTP
  if(ftp){
    if(ftp.value) check_flv = 0;
  }
  
  if(mode == 2){
    check_flv = document.getElementById('fav_upload_flv').checked ? 1 : 0;
    check_img = document.getElementById('fav_upload_image').checked ? 1 : 0;
  }

  var ok = true;

  if(nazev){ //nazev
    if(nazev.value.length == 0){
      alert(text_upload_echo_1);
      ok = false;
    }
  }

  if(popis){ //popis
    if(popis.value.length == 0){
      alert(text_upload_echo_2);
      ok = false;
    }
  }

/*
  if(keywords){ //popis
    if(keywords.value.length == 0){
      alert(text_upload_echo_3);
      ok = false;
    }else{
      var reg = new RegExp("^[ a-zA-ZěščřžýáííéúůĚŠČŘŽÝÁÍÉÚŮňŇ0-9]*$");
      if(!reg.test(keywords.value)){
        alert(text_upload_echo_6);
        ok = false;
      }
    }
  }
*/

  if(check_flv){
  
    if(file.value){
      ext = file.value.substring(file.value.length-3, file.value.length);
      ext = ext.toLowerCase();

      if(!mode){
        //normal user - avi, wmv
        if((ext != upload_extension_0) && (ext != upload_extension_1)){
          alert(text_upload_echo_4);
          ok = false;
        }
      }else{
        //admin
        if(ext != "flv"){
          alert(text_upload_echo_4);
          ok = false;
        }
      }

    }else{
      alert(text_upload_echo_5);
      ok = false;
    }
  }

  if(check_img){

    if(pic != "normal_user"){
      if(pic.value){
        ext = pic.value.substring(pic.value.length-3, pic.value.length);
        ext = ext.toLowerCase();
        //jpg, git, png
        if((ext != 'jpg') && (ext != 'gif') && (ext != 'png')){
          alert(text_upload_echo_7);
          ok = false;
        }
      }else{
       // alert(text_upload_echo_6);
       // ok = false;
      }
    }
    
  }

  return ok;
}

function check_form_video_upload2(){

  //normal user - upload-video.php
  var nazev = document.getElementById('video_title');
  var popis = document.getElementById('video_description');
  var file = document.getElementById('video_file');

  var ok = true;

  if(nazev){ //nazev
    if(nazev.value.length == 0){
      alert(text_upload_echo_1);
      ok = false;
    }
  }

  if(popis){ //popis
    if(popis.value.length == 0){
      alert(text_upload_echo_2);
      ok = false;
    }
  }

  if(file.value){
    ext = file.value.substring(file.value.length-3, file.value.length);
    ext = ext.toLowerCase();

    //normal user - avi, wmv
    if((ext != upload_extension_0) && (ext != upload_extension_1) && (ext != upload_extension_2) && (ext != upload_extension_3)){
      alert(text_upload_echo_4);
      ok = false;
    }

  }else{
    alert(text_upload_echo_5);
    ok = false;
  }


  return ok;
}

function checkRegular(exp, str){
  if(exp != "" && str != ""){
    if (str.match(exp)) {
      return true;
    }
    else{
      return false;
    }
  }
}