Proses FIFO feat. @mizno

ProcessFifo.php

<?php

function ProcessFifo($code, $quantity, $data) {
	$result = array();
	$counter = $quantity;
	// proses
	foreach ($data as $row) {
		if ($counter > 0) {
			if ($row['code'] == $code) {
				if ($row['stock'] >= $counter) {
					$row['stock'] = $counter;
					$counter = 0;
				} else {
					$counter -= $row['stock'];
				}
			}
			$result[] = $row;
		}
	}
	// jika stok kurang
	if ($counter > 0) {
		$result = 'Stock KURANG!';
	}
	// return result
	return $result;
}

$code = isset($_GET['code']) ? $_GET['code'] : 'a';
$buy = isset($_GET['buy']) ? $_GET['buy'] : 10;
$query = array(
	array('id' => 1, 'code' => 'a', 'stock' => 8, 'h' => 100),
	array('id' => 2, 'code' => 'a', 'stock' => 4, 'h' => 110),
	array('id' => 3, 'code' => 'a', 'stock' => 3, 'h' => 90),
	array('id' => 4, 'code' => 'a', 'stock' => 5, 'h' => 105)
);

$result = ProcessFifo($code,$buy,$query);
print '<pre>';
print_r($result);
print '</pre>';