<?php
     $booksid = $_GET[booksid];     //the product id from the URL
     $action  = $_GET[action]; //the action from the URL
 
     //if there is an product_id and that product_id doesn't exist     display an error message
     if($booksid && !productExists($booksid)) {
         die("Error. Product Doesn't Exist");
     }
 
     switch($action) {    //decide what to do    
 
         case "add":
             $_SESSION['cart'][$booksid]++; //add one to the quantity of the product with id $product_id
         break;
 
         case "remove":
             $_SESSION['cart'][$booksid]--; //remove one from the quantity of the product with id $product_id
             if($_SESSION['cart'][$booksid] == 0) unset($_SESSION['cart'][$booksid]); //if the quantity is zero, remove it completely (using the 'unset' function) - otherwise is will show zero, then -1, -2 etc when the user keeps removing items.
         break;
 
         case "empty":
             unset($_SESSION['cart']); //unset the whole cart, i.e. empty the cart.
         break;
 
     }
	      if($_SESSION['cart']) {    //if the cart isn't empty
         //show the cart
 
         echo "<table border=\"1\" padding=\"3\" width=\"40%\">";    //format the cart using a HTML table
 
             //iterate through the cart, the $product_id is the key and $quantity is the value
             foreach($_SESSION['cart'] as $booksid => $quantity) {    
 
                 //get the name, description and price from the database - this will depend on your database implementation.
                 //use sprintf to make sure that $product_id is inserted into the query as a number - to prevent SQL injection
                 $sql = sprintf("SELECT title, author, price, category FROM books WHERE booksid = %d;",
                                 $booksid);
 
                 $result = mysql_query($sql);
 
				 //insert books value into cart
				$sql = "INSERT INTO cart (cartid, cartqty, cartsessionid,)
              	VALUES ($cartid, 1, 1)";
      			$result = dbQuery($sql);
 
                 //Only display the row if there is a product (though there should always be as we have already checked)
                 if(mysql_num_rows($result) > 0) {
 
                     list($title, $author, $price, $category) = mysql_fetch_row($result);
 
                     $line_cost = $price * $quantity;        //work out the line cost
                     $total = $total + $line_cost;            //add to the total cost
 
                     echo "<tr>";
                         //show this information in table cells
                         echo "<td align=\"center\">$title</td>";
                         //along with a 'remove' link next to the quantity - which links to this page, but with an action of remove, and the id of the current product
                         echo "<td align=\"center\">$quantity <a href=\"$_SERVER[PHP_SELF]?action=remove&id=$booksid\">X</a></td>";
                         echo "<td align=\"center\">$line_cost</td>";
 
                     echo "</tr>";
 
                 }
 
             }
 
             //show the total
             echo "<tr>";
                 echo "<td colspan=\"2\" align=\"right\">Total</td>";
                 echo "<td align=\"right\">$total</td>";
             echo "</tr>";
 
             //show the empty cart link - which links to this page, but with an action of empty. A simple bit of javascript in the onlick event of the link asks the user for confirmation
             echo "<tr>";
                 echo "<td colspan=\"3\" align=\"right\"><a href=\"$_SERVER[PHP_SELF]?action=empty\" onclick=\"return confirm('Are you sure?');\">Empty Cart</a></td>";
             echo "</tr>";        
         echo "</table>";
 
 
 
     }else{
         //otherwise tell the user they have no items in their cart
         echo "You have no items in your shopping cart.";
 
     }    
 
	 function productExists($booksid) {
             //use sprintf to make sure that $product_id is inserted into the query as a number - to prevent SQL injection
             $sql = sprintf("SELECT * FROM books WHERE booksid = %d;",
                             $booksid);
 
             return mysql_num_rows(mysql_query($sql)) > 0;
     }
 
 
	 ?>

<?php require_once('../Connections/myDatabase.php'); ?>
<?php
if (!function_exists("GetSQLValueString")) {
function GetSQLValueString($theValue, $theType, $theDefinedValue = "", $theNotDefinedValue = "") 
{
  $theValue = get_magic_quotes_gpc() ? stripslashes($theValue) : $theValue;
 
  $theValue = function_exists("mysql_real_escape_string") ? mysql_real_escape_string($theValue) : mysql_escape_string($theValue);
 
  switch ($theType) {
    case "text":
      $theValue = ($theValue != "") ? "'" . $theValue . "'" : "NULL";
      break;    
    case "long":
    case "int":
      $theValue = ($theValue != "") ? intval($theValue) : "NULL";
      break;
    case "double":
      $theValue = ($theValue != "") ? "'" . doubleval($theValue) . "'" : "NULL";
      break;
    case "date":
      $theValue = ($theValue != "") ? "'" . $theValue . "'" : "NULL";
      break;
    case "defined":
      $theValue = ($theValue != "") ? $theDefinedValue : $theNotDefinedValue;
      break;
  }
  return $theValue;
}
}
 
mysql_select_db($database_myDatabase, $myDatabase);
$query_title = "SELECT * FROM books WHERE books.booksid = 1";
$title = mysql_query($query_title, $myDatabase) or die(mysql_error());
$row_title = mysql_fetch_assoc($title);
$totalRows_title = mysql_num_rows($title);
?><!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Untitled Document</title>
</head>
 
<body>
<table border="1">
 
	<tr>
	  <td>&nbsp;</td>
	  <td>Title</td>
	  <td>Author</td>
	  <td>Price</td>
	  <td>Category</td>
	  <td>&nbsp;</td>
  </tr>
	<tr>
	  <td><?php echo $row_title['booksid']; ?></td>
      <td><?php echo $row_title['title']; ?></td>
	  <td><?php echo $row_title['author']; ?></td>
      <td><?php echo $row_title['price']; ?></td>
      <td><?php echo $row_title['category']; ?></td>
  <td><a href="Cart.php?action=add&id=1">Add To Cart</a></td></tr></table>
 
 
<a href="Cart.php">View Cart</a>
 
</body>
</html>
<?php
mysql_free_result($title);
?>