function buy_stock($symb, $comment = '', $volume = 0)
{
// moves stock from the cart to trades and updates pf_summary
global $db_hostname, $db_database, $db_user, $db_password;
$portfolio = new portfolio($_SESSION['pfid']);
$pfid = $portfolio->getID();
$date = $portfolio->getWorkingDate();
$exch = $portfolio->getExch()->getID();
$commission = $portfolio->getCommission();
$close = get_stock_close($symb, $date, $exch);
if ($comment == '') {
$comment = "{$name}: {$date}";
}
if ($volume != 0) {
$qty = $volume;
} else {
// this means that a volume of '0' buys one parcel's worth.
// is that what we want?
if ($close < $parcel) {
$qty = (int) ($parcel / $close);
} else {
$qty = 1;
}
}
// take the absolute value of $qty since we set aside the purchase price as an asset for a short.
$total = $close * abs($qty);
try {
$pdo = new PDO("pgsql:host={$db_hostname};dbname={$db_database}", $db_user, $db_password);
$pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
} catch (PDOException $e) {
die("ERROR: Cannot connect: " . $e->getMessage());
}
// find out how much money, and stocks are in the portfolio today
$query = "select cash_in_hand, holdings from pf_summary where pfid = '{$pfid}' and date = '{$date}';";
foreach ($pdo->query($query) as $row) {
$cash_in_hand = $row['cash_in_hand'];
$holdings = $row['holdings'];
}
$duty = $total * ($portfolio->getTaxRate() / 100);
if ($cash_in_hand < $total + $duty + $commission) {
// we can't afford this one!
return false;
}
$cash_in_hand = $cash_in_hand - $total - $duty - $commission;
$holdings = $holdings + $total;
try {
$query = "select nextval('trades_trid_seq') as trid;";
$result = $pdo->query($query);
$row = $result->fetch(PDO::FETCH_ASSOC);
$next_trid = $row['trid'];
} catch (PDOException $e) {
tr_warn('buy_stock:' . $query . ':' . $e->getMessage());
return false;
}
try {
$query = "select nextval('holdings_hid_seq') as hid;";
$result = $pdo->query($query);
$row = $result->fetch(PDO::FETCH_ASSOC);
$next_hid = $row['hid'];
} catch (PDOException $e) {
tr_warn('buy_stock:' . $query . ':' . $e->getMessage());
return false;
}
try {
$pdo->beginTransaction();
// add the trade to the trades table
$query = "insert into trades (trid, pfid, hid, date, symb, price, volume, comment, tr_type) values ('{$next_trid}', '{$pfid}', '{$next_hid}', '{$date}', '{$symb}', '{$close}', '{$qty}', '{$comment}', 'O');";
$pdo->exec($query);
// add the transaction to the holdings table
$query = "insert into holdings (hid, pfid, date, symb, price, volume, comment) values ('{$next_hid}', '{$pfid}', '{$date}', '{$symb}', '{$close}', '{$qty}', '{$comment}');";
$pdo->exec($query);
// update the pf_summary with the trade
$query = "update pf_summary set cash_in_hand = '{$cash_in_hand}', holdings = '{$holdings}' where date = '{$date}' and pfid = '{$pfid}';";
$pdo->exec($query);
$pdo->commit();
} catch (PDOException $e) {
$pdo->rollBack();
tr_warn('buy_stock:' . $query . ':' . $e->getMessage());
return false;
}
return true;
}
