function trim(inputString) {
   if (typeof inputString != "string") { return inputString; }
   var retValue = inputString;
   var ch = retValue.substring(0, 1);
   while (ch == " ") { // Check for spaces at the beginning of the string
      retValue = retValue.substring(1, retValue.length);
      ch = retValue.substring(0, 1);
   }
   ch = retValue.substring(retValue.length-1, retValue.length);
   while (ch == " ") { // Check for spaces at the end of the string
      retValue = retValue.substring(0, retValue.length-1);
      ch = retValue.substring(retValue.length-1, retValue.length);
   }
   while (retValue.indexOf("  ") != -1) { // Note that there are two spaces in the string - look for multiple spaces within the string
      retValue = retValue.substring(0, retValue.indexOf("  ")) + retValue.substring(retValue.indexOf("  ")+1, retValue.length); // Again, there are two spaces in each of the strings
   }
   return retValue; // Return the trimmed string back to the user
}

	function fieldCheckEmpty(field, name)
	{
		if(trim(field.value)=="")
		{
			alert("Uzupelnij pole: "+name);
			field.focus();
			return false;
		}
		return true;
	}

	function fieldCheckEmptyLen(field, name, len)
	{
		if (fieldCheckEmpty(field, name)==false) return false;
		if (len>0 && field.value.length<len)
		{
			alert("Za krotkie haslo: "+name);
			field.focus();
			return false;
		}
		return true;
	}

	function fieldCheckAlphaNum(field, name)
	{
		for (i=0; i<field.value.length; i++)
		{
			if (!((field.value.charAt(i)>='a' && field.value.charAt(i)<='z') || 
				  (field.value.charAt(i)>='A' && field.value.charAt(i)<='Z') || 
				  (field.value.charAt(i)>='0' && field.value.charAt(i)<='9'))) 
			{
				alert("Pole "+name+" moze zawierac tylko male i duze litery alfabetu angielskiego albo cyfry.");
				field.focus();
				return false;
			}
		}
	}

	function fieldCheckEmptyLenAlphaNum(field, name, len)
	{
		if (fieldCheckEmptyLen(field, name, len)==false) return false;
		if (fieldCheckAlphaNum(field, name)==false) return false;
		return true;
	}

	function fieldCheckNumber(field)
	{
		var str = String(parseInt(field.value));
		if(field.value != str)
		{
			alert("To musi byc liczba calkowita");
			field.focus();
			field.value="";
			return false;
		}
		return true;
	}

      function fieldPictureOrDocumentName(field, name)
        {
                if(trim(field.value)=="") return true;
                var i = field.value.indexOf('.');
                if (i>0)
                {
                        var p = field.value.substring(i+1, field.value.length);
                        if (p=='jpg' || p=='jpeg' || p=='gif' || p=='doc' || p=='pdf')
                        return true;
                }
                alert("Nieprawidlowy format pliku. Plik moze byc typu doc, pdf, jpg lub gif,.");
                field.focus();
                return false;
        }


	function fieldCheckPassword(passField, confirmField, len)
	{
		if (fieldCheckEmpty(passField, "haslo")==false) return false;
		if (fieldCheckEmpty(confirmField, "potwierdz haslo")==false) return false;
		if (fieldCheckAlphaNum(passField, "haslo")==false) return false;
		if (passField.value!=confirmField.value)
		{
			alert("Haslo i potwierdzenie musza byc takie same");
			passField.value="";
			confirmField.value="";
			passField.focus();
			return false;
		}
		if (passField.value.length<len)
		{
			alert("Za krotkie haslo");
			passField.value="";
			confirmField.value="";
			passField.focus();
			return false;
		}
		return true;
	}



	function fieldCheckEmail(field, name)
	{
		if (fieldCheckEmpty(field, name)==false) return false;
		var i = field.value.indexOf('@');
		if (i>0)
		{
			var p = field.value.substring(i+1, field.value.length);
			i = p.indexOf('.');
			if (i>0) 
				return true;
		}
		alert("Nieprawidlowy email: "+name);
		field.focus();
		return false;
	}

	function fieldPictureName(field, name)
	{
		if (fieldCheckEmpty(field, name)==false) return false;
		var i = field.value.indexOf('.');
		if (i>0)
		{
			var p = field.value.substring(i+1, field.value.length);
			if (p=='jpg' || p=='jpeg' || p=='gif')
			return true;
		}
		alert("Nieprawidlowy format pliku. Zdjecie moze byc typu gif albo jpg.");
		field.focus();
		return false;
	}

	function fieldPictureName1(field, name)
	{
		if(trim(field.value)=="") return true;
		var i = field.value.indexOf('.');
		if (i>0)
		{
			var p = field.value.substring(i+1, field.value.length);
			if (p=='jpg' || p=='jpeg' || p=='gif')
			return true;
		}
		alert("Nieprawidlowy format pliku. Zdjecie moze byc typu gif albo jpg.");
		field.focus();
		return false;
	}
	
	function fieldDocumentName(field, name)
	{
		if (fieldCheckEmpty(field, name)==false) return false;
		var i = field.value.indexOf('.');
		if (i>0)
		{
			var p = field.value.substring(i+1, field.value.length);
			if (p=='doc' || p=='pdf')
			return true;
		}
		alert("Nieprawidlowy format pliku. Przyjmujemy dokumenty w formacie pdf albo doc.");
		field.focus();
		return false;
	}