credit system for an auction site having a problem

[barnfold]

hi

im using geo auctions lite and bungling my way through the coding of adding a credit system

bare with me on this heheh !

ok ive added a bidcredit row to a table with a default of 500

so everyone when register gets 500 credits

now they can place bids etc with the exisitng script

its using class files (functions) and cases in one main file

i think its processing the bids checking the login and that the auction exists etc etc

i would like to know how to place a a bit of code in the processing bid function to check if the user has enough credits and deduct them from the bidcredit total ( in this case i think the bid row in the auctions table from the bidcredit row in the logindata table...........

im sure its easy but my method of cutting and pasting and chopping is not working so far...

hope you can help

regards

[barnfold]

hope this isnt getting to confusing by doing this
i thought i add some of the code that already exists

is this (poor) pseudo code getting close at all...

if bidcredit = 0
return an error message

if bid_amount > bidcredit
return an error message

else if bid_amount <= bidcredit
it ok to carry on

where should i place a piece of code to check a users credit amount
I.E in the class file or in the main file in the case ?

**************************************************here is the snippet from the main auction file (SNIPPET FROM CLaSS FILE FOLLOWS )******************************

case 8:
//process a bid
//sellers_id is b
include("classes/auction_browse_class.php");
$auction_browse = new Auction_browse($auth_auctions_103);
$auction_browse->auction_close($db);
include("auctionheader.htm");
if (!$auth_auctions_103->auction_user_id)
{
$auth_auctions_103->auth_messages["login"] = $auth_auctions_103->messages[832];
$auth_auctions_103->login_form();
}
else
{
include("classes/auction_bid_class.php");
$bid = new Auction_bid();
if (($b) && ($c))
{
if (!$bid->process_bid($db,$b,$auth_auctions_103->auction_user_id,$c))
{
$bid->bid_error();
}
else
{
//successful bid
if (!$bid->display_successful_bid($db,$b))
{
$bid->bid_error();
}
else
{
if (!$bid->mail_confirmation($db,$b,$auth_auctions_103->auction_user_id))
$bid->bid_error();
}
}
}
elseif ($b)
{
if (!$bid->prepare_bid($db,$auth_auctions_103->auction_user_id,$b))
{
$bid->bid_error();
}
}
else
{
$bid->error_message = $bid->messages[2312];
$bid->bid_error();
}
}
include("auctionfooter.htm");
exit;
break;

*************************************************SNIPPET FROM THE AUCTION_BID_CLASS file FUNCTION PROCESS BID if the whole code is needed ask 🙂 ********

function process_bid($db,$auction_id=0,$bidder=0,$bid_amount=0)
{
if ($auction_id)
{
if ($bidder)
{
if ($bid_amount)
{
//check to if bid_amount is above or = to the minimum bid
$sql_query = "select * from ".$this->auctions_table." where id = ".$auction_id;
//echo $sql_query." is the query<br>\n";
$result = &$db->Execute($sql_query);
if (!$result)
{
//echo $sql_query." is the query<br>\n";
$this->error_message = $this->messages[2313];
return false;
}
elseif ($result->RecordCount() == 1)
{
$show = $result->FetchNextObject();