Why isn't working my notifications script with sales module? - php

Question

The sales notifications is not working because this line amountArray[$idproduct] += $amount; is returning me offset. I don't know how to fix it.
My full function is this:
function saveAllSaleDetails($idsale, $sale) {
$this->conexion->startTransaction();
$amountArray = [];
try {
foreach ($sale as $detail):
$idproduct = $detail['id'];
$amount = $detail['amount'];
$price = $detail['price'];
$subtotal = $detail['subtotal'];
$iduser = 1;
$this->saveSaleDetail($idsale, $idproduct, $amount, $price, $subtotal, $iduser);
$amountArray[$idproduct] += $amount;
$stock = $this->product->getProductStock($idproduct);
$stock = $stock[0][0] - $amountArray[$idproduct];
if ($stock <= 20) {
$product = $this->product->getProductById($idproduct);
$message = $product[0][1]." stock is bellow 20.";
notification::add($message, $idproduct, 'warning', 'product.php');
}
endforeach;
$this->conexion->commit();
$this->conexion->cerrar();
return true;
} catch (Exception $e) {
$this->conexion->rollback();
$this->conexion->cerrar();
var_dump($e->getMessage());
return false;
}
}

Answer 1

The problem is because of this line,
$amountArray[$idproduct] += $amount;
The above statement can be expanded as
$amountArray[$idproduct] = $amountArray[$idproduct] + $amount;
Initially during the first iteration of foreach loop, $amountArray[1] and $amountArray[2] are not set, and hence you're getting these undefined offset error.
So instead of
$amountArray[$idproduct] += $amount;
Do this:
$amountArray[$idproduct] = isset($amountArray[$idproduct]) ? $amountArray[$idproduct] + $amount : $amount;