Code that will appearing NOT AVAILABLE button using if else that disable to adding in a cart from menu

Need help for code that will appearing not available button using if else that can disable to adding in a cart if the food is not available

    <?php
include('connection.php');
$cat=$_GET['category'];
$result = mysql_query("SELECT * FROM menu where category='$cat' ");
while($row = mysql_fetch_array($result))
{
echo '
<form name="Form1" method="post" action="">
<img src="'.$row['picture'].'" alt="" align="top" border="0" style="width:82px;height:75px;">
<font style="font-size:19px" color="#000000" face="Arial">'.$row['foods'].'</font></div>
<font style="font-size:13px" color="#000000" face="Arial">'.$row['price'].' pesos</font>
<a href="addcart2.php?productid='.$row['productid'].'&&category='.$row['category'].'"><img src="images/button.png" id="Image2" alt="" align="top" border="0" style="width:80px;height:26px;"></a>
</form> ';
}
?>