String.prototype.trim = function() { return this.replace(/^\s+|\s+$/g, ''); };
	function checkUncheckAll(cnt)
	{
		checked = false;
		unchecked = false;
		for (i = 0; i < cnt; i++)
		{
			box = eval("document.message_list.check_mail_" + i);
			if (box.checked == false)
			{
				unchecked = true;
			}
			else
			{
				checked = true;
			}
		}
		if (checked == true && unchecked == true)
			for (i = 0; i < cnt; i++)
			{
				box = eval("document.message_list.check_mail_" + i);
				box.checked = true;
			}
		else if (checked == true)
			for (i = 0; i < cnt; i++)
			{
				box = eval("document.message_list.check_mail_" + i);
				box.checked = false;
			}
		else
			for (i = 0; i < cnt; i++)
			{
				box = eval("document.message_list.check_mail_" + i);
				box.checked = true;
			}
	}
	
	function testAllCheckbox(checkall,cnt)
	{
		checked = false;
		unchecked = false;
		for (i = 0; i < cnt; i++)
		{
			box = eval("document.message_list.check_mail_" + i);
			if (box.checked == false)
			{
				unchecked = true;
			}
			else
			{
				checked = true;
			}
		}
		if (checked == true && unchecked == true)
			checkall.checked = false;
		else if (checked == true)
			checkall.checked = true;
		else
			checkall.checked = false;
	}
	
	function testAllCheckbox(checkall,cnt)
	{
		checked = false;
		unchecked = false;
		for (i = 0; i < cnt; i++)
		{
			box = eval("document.message_list.check_mail_" + i);
			if (box.checked == false)
			{
				unchecked = true;
			}
			else
			{
				checked = true;
			}
		}
		if (checked == true && unchecked == true)
			checkall.checked = false;
		else if (checked == true)
			checkall.checked = true;
		else
			checkall.checked = false;
	}
	
	function checkUncheckNewsletterAll(cnt)
	{
		checked = false;
		unchecked = false;
		for (i = 0; i < cnt; i++)
		{
			box = eval("document.newsletter_list.check_newsletter_" + i);
			if (box.checked == false)
			{
				unchecked = true;
			}
			else
			{
				checked = true;
			}
		}
		if (checked == true && unchecked == true)
			for (i = 0; i < cnt; i++)
			{
				box = eval("document.newsletter_list.check_newsletter_" + i);
				box.checked = true;
			}
		else if (checked == true)
			for (i = 0; i < cnt; i++)
			{
				box = eval("document.newsletter_list.check_newsletter_" + i);
				box.checked = false;
			}
		else
			for (i = 0; i < cnt; i++)
			{
				box = eval("document.newsletter_list.check_newsletter_" + i);
				box.checked = true;
			}
	}
	function testAllNewsletterCheckbox(checkall,cnt)
	{
		checked = false;
		unchecked = false;
		for (i = 0; i < cnt; i++)
		{
			box = eval("document.newsletter_list.check_newsletter_" + i);
			if (box.checked == false)
			{
				unchecked = true;
			}
			else
			{
				checked = true;
			}
		}
		if (checked == true && unchecked == true)
			checkall.checked = false;
		else if (checked == true)
			checkall.checked = true;
		else
			checkall.checked = false;
	}
	function testCheckRights(text)
	{
		box = eval("document.upload_photo.check_rights");
		if (box.checked == true)
			checked = true;
		else
			checked = false;
		if (checked == false)
			window.alert(text);
		return box.checked;
	}
	function showDialog(text)
	{
		if(window.confirm(text))
			return true;
		else
			return false;
	}
	function check_cat(cnt,max_cnt)
	{
		checked = false;
		unchecked = false;
		count = 0;
		for (i = 0; i < cnt; i++)
		{
			box = eval("document.upload_photo.check_category_" + i);
			if (box.checked == true)
			{
				count++;
			}
		}
		if (count > max_cnt-1)
			for (i = 0; i < cnt; i++)
			{
				box = eval("document.upload_photo.check_category_" + i);
				if (box.checked == false)
					box.disabled = true;
			}
		else
			for (i = 0; i < cnt; i++)
			{
				box = eval("document.upload_photo.check_category_" + i);
				box.disabled = false;
			}
	}
	function check_cat2(cnt,max_cnt)
	{
		checked = false;
		unchecked = false;
		count = 0;
		for (i = 0; i < cnt; i++)
		{
			box = eval("document.photochange.check_category_" + i);
			if (box.checked == true)
			{
				count++;
			}
		}
		if (count > max_cnt-1)
			for (i = 0; i < cnt; i++)
			{
				box = eval("document.photochange.check_category_" + i);
				if (box.checked == false)
					box.disabled = true;
			}
		else
			for (i = 0; i < cnt; i++)
			{
				box = eval("document.photochange.check_category_" + i);
				box.disabled = false;
			}
	}
	// kontroluje zda je zadano vse, co ma
	function kontrolaField(field,text) {
		var fields_ok = (field.trim() != "");
		if (fields_ok == false) window.alert(text);
		return (fields_ok);
	}
	// kontroluje zda je zadano vse, co ma
	function toggleVisibility(id_link,link_text_1,link_text_2,id_display) {
		if (document.getElementById(id_display).style.display == "none") {
			document.getElementById(id_display).style.display = "block";
			document.getElementById(id_link).text = link_text_1;
		}
		else {
			document.getElementById(id_display).style.display = "none";
			document.getElementById(id_link).text = link_text_2;
		}
		return true;
	}