my shopping cart is messing with my head

[mackevin]

I have code for a basic shopping cart system, and its was working fine till I added a postage part, now when I add something to my cart it adds the same item twice, wierd I know.

 

Also if the value of quantity goes up past five how do I apply a second value to that incremental, so 1-5 would be R20 postage 6-10 would be R30 11-15 would be 40 etc etc please could someone offer me some advice please

 

here is the code:

<?php

 

if (isset($_GET["shopping_cart"]) || isset($_POST["shopping_cart"]))

{

 

if (isset($_GET["add2cart"]) && $_GET["add2cart"]>0) //add product to cart with productID=$add

{

 

$q = db_query("select in_stock from ".PRODUCTS_TABLE." where productID='".$_GET["add2cart"]."'") or die (db_error());

$is = db_fetch_row($q); $is = $is[0];

 

//$_SESSION[gids] contains product IDs

//$_SESSION[counts] contains product quantities ($_SESSION[counts][$i] corresponds to $_SESSION[gids][$i])

//$_SESSION[gids][$i] == 0 means $i-element is 'empty'

if (!isset($_SESSION["gids"]))

{

$_SESSION["gids"] = array();

$_SESSION["counts"] = array();

}

//check for current item in the current shopping cart content

$i=0;

while ($i<count($_SESSION["gids"]) && $_SESSION["gids"][$i] != $_GET["add2cart"]) $i++;

if ($i < count($_SESSION["gids"])) //increase current product's quantity

{

$_SESSION["counts"][$i]++;

}

else //no item - add it to $gids array

{

$_SESSION["gids"][] = $_GET["add2cart"];

$_SESSION["counts"][] = 0;

}

 

header("Location: index.php?shopping_cart=yes");

 

}

 

 

if (isset($_GET["remove"]) && $_GET["remove"] > 0) //remove from cart product with productID == $remove

{

$i=0;

while ($i<count($_SESSION["gids"]) && $_SESSION["gids"][$i] != $_GET["remove"]) $i++;

if ($i<count($_SESSION["gids"])) $_SESSION["gids"][$i] = 0;

 

header("Location: index.php?shopping_cart=yes");

}

 

 

if (isset($_POST["update"])) //update shopping cart content

{

 

foreach ($_POST as $key => $val)

if (strstr($key, "count_"))

{

  //select product's in stock level

  $q = db_query("select in_stock from ".PRODUCTS_TABLE." where productID='".str_replace("count_","",$key)."'") or die (db_error());

  $is = db_fetch_row($q); $is = $is[0];

 

if ($val > 0)

{

for ($i=0; $i<count($_SESSION["gids"]); $i++)

{

if ($_SESSION["gids"][$i] == str_replace("count_","",$key))

{

$_SESSION["counts"][$i] = floor($val);

}

}

}

else //remove

{

$i=0;

while ($_SESSION["gids"][$i] != str_replace("count_","",$key) && $i<count($_SESSION["gids"])) $i++;

$_SESSION["gids"][$i] = 0;

}

  }

 

header("Location: index.php?shopping_cart=yes");

 

}

 

if (isset($_GET["clear_cart"])) //completely clear shopping cart

{

//clear cart

unset($_SESSION["gids"]);

unset($_SESSION["counts"]);

 

header("Location: index.php?shopping_cart=yes");

}

 

 

 

//shopping cart items count

$c = 0;

if (isset($_SESSION["gids"]))

for ($j=0; $j<count($_SESSION["gids"]); $j++)

if ($_SESSION["gids"][$j]) $c += $_SESSION["counts"][$j];

 

//not empty?

if (isset($_SESSION["gids"]) && $c)

{

$k = 0; //total cart value

$products = array();

for ($i=0; $i<count($_SESSION["gids"]); $i++)

  if ($_SESSION["gids"][$i])

  {

$q = db_query("SELECT name, Price, product_code FROM ".PRODUCTS_TABLE." WHERE productID='".$_SESSION["gids"][$i]."'") or die (db_error());

if ($r = db_fetch_row($q))

{

$tmp = array("id"=>$_SESSION["gids"][$i], "name"=>$r[0], "quantity"=>$_SESSION["counts"][$i], "cost"=>show_price($_SESSION["counts"][$i]*$r[1]), "product_code"=>$r[2]);

 

$products[] = $tmp;

 

$k += $_SESSION["counts"][$i]*$r[1];

$p += $_SESSION["counts"][$i]*$r[1];

$p = 20;

}

 

  }

 

//total...

$smarty->assign("cart_content", $products);

$smarty->assign("cart_total", show_price($p + $k));

$smarty->assign('postage', show_price($p));

}

else

{

$smarty->assign("cart_total", "");

}

 

$smarty->assign("main_content_template", "shopping_cart.tpl.html");

 

 

}

?>