function VerifyGuestbookForm(guestbookForm) {
  var why = "";
  var confirmCode = "";
  var codeConverse = new Array();
  var now = new Date();
  var dateRatio = now.getFullYear()*(now.getMonth()+1)*now.getDate();
  
  codeConverse[1] = "a";
  codeConverse[2] = "b";
  codeConverse[3] = "c";
  codeConverse[4] = "d";
  codeConverse[5] = "e";
  codeConverse[6] = "f";
  codeConverse[7] = "g";
  codeConverse[8] = "h";
  codeConverse[9] = "i";
  codeConverse[10] = "j";
  codeConverse[11] = "k";
  codeConverse[12] = "l";
  codeConverse[13] = "m";
  codeConverse[14] = "n";
  codeConverse[15] = "o";
  codeConverse[16] = "p";
  codeConverse[17] = "q";
  codeConverse[18] = "r";
  codeConverse[19] = "s";
  codeConverse[20] = "t";
  codeConverse[21] = "u";
  codeConverse[22] = "v";
  codeConverse[23] = "w";
  codeConverse[24] = "x";
  codeConverse[25] = "y";
  codeConverse[26] = "z";
  codeConverse[27] = "A";
  codeConverse[28] = "B";
  codeConverse[29] = "C";
  codeConverse[30] = "D";
  codeConverse[31] = "E";
  codeConverse[32] = "F";
  codeConverse[33] = "G";
  codeConverse[34] = "H";
  codeConverse[35] = "I";
  codeConverse[36] = "J";
  codeConverse[37] = "K";
  codeConverse[38] = "L";
  codeConverse[39] = "M";
  codeConverse[40] = "N";
  codeConverse[41] = "O";
  codeConverse[42] = "P";
  codeConverse[43] = "Q";
  codeConverse[44] = "R";
  codeConverse[45] = "S";
  codeConverse[46] = "T";
  codeConverse[47] = "U";
  codeConverse[48] = "V";
  codeConverse[49] = "W";
  codeConverse[50] = "X";
  codeConverse[51] = "Y";
  codeConverse[52] = "Z";
  codeConverse[53] = "0";
  codeConverse[54] = "1";
  codeConverse[55] = "2";
  codeConverse[56] = "3";
  codeConverse[57] = "4";
  codeConverse[58] = "5";
  codeConverse[59] = "6";
  codeConverse[60] = "7";
  codeConverse[61] = "8";
  codeConverse[62] = "9";

  confirmCode = codeConverse[(guestbookForm.confirmCode1.value/dateRatio)];
  confirmCode += codeConverse[(guestbookForm.confirmCode2.value/dateRatio)];
  confirmCode += codeConverse[(guestbookForm.confirmCode3.value/dateRatio)];
  confirmCode += codeConverse[(guestbookForm.confirmCode4.value/dateRatio)];
  confirmCode += codeConverse[(guestbookForm.confirmCode5.value/dateRatio)];
  confirmCode += codeConverse[(guestbookForm.confirmCode6.value/dateRatio)];

  if(guestbookForm.jmeno.value == ""){
    why += "Před odesláním zadejte své jméno.\n";
  }
  if(guestbookForm.text.value == ""){
    why += "Před odesláním zadejte text příspěvku.\n";
  }
  if (guestbookForm.email.value != ""){
	  why += checkEmail(guestbookForm.email.value);
  }
   if(guestbookForm.confirmCode.value != confirmCode){
    why += "\nZadejte správný potvrzovací kód!\n(řetězec znaků pod ikonami smajlíků)";
  }

//  why += dateSum;

  if (why != ""){
    alert(why);
    return false;
  }

  return true;
}

function VerifyQuickSearchForm(searchForm) {
  var why = "";

  if(searchForm.phrase.value == ""){
    why += "Před odesláním zadejte hledaný řetězeci!\n";
  }

  StrLen = searchForm.phrase.value.length;
  if(StrLen<3 ){
    why += "Hledaný řetězec musí obsahovat alespoň 3 znaky!\n";
  }
  
  if (why != ""){
    alert(why);
    return false;
  }

  return true;
}

function checkEmail (strng) {
  var error = "";

  var emailFilter=/^.+@.+\..{2,4}$/;
  if (!(emailFilter.test(strng))) {
    error += "Zadaná e-mailová adresa nemá platný formát.\n";
  }

  var illegalChars= /[\(\)\<\>\,\;\:\\\\[\]]/
  if (strng.match(illegalChars)) {
    error += "Zadaná e-mailová adresa obsahuje nepovolené znaky.\n";
  }
  return error;
}