<?php
/*
Developer: David Kumwenda
Contact: 0881161942 or 0996139030
App: Mpamba 4 MSE
Date: 30 August 2025
Duration: 1 day dev work*/
 

// Read raw POST data
$rawData = file_get_contents("php://input");

// Decode JSON
$data = json_decode($rawData, true);

// Basic logging (optional, useful for debugging)
file_put_contents("logs/callback_log_".date('Ymd').'.txt', date("Y-m-d H:i:s") . " - " . $rawData . PHP_EOL, FILE_APPEND); exit(); 

// Validate required fields
if (isset($data["receipt_number"], $data["result_code"], $data["transaction_id"])) {
    
    $receiptNumber = $data["receipt_number"];
    $resultCode = $data["result_code"];
    $resultDescription = $data["result_description"] ?? "";
    $resultTime = $data["result_time"] ?? date("Y-m-d H:i:s");
    $transactionId = $data["transaction_id"];
    $success = $data["success"] ?? false;

    // Example: Save to database
    // (Replace this with your actual DB insert/update code)
    /*
    $conn = mysqli_connect("localhost", "user", "password", "dbname");
    $stmt = mysqli_prepare($conn, "INSERT INTO payments (transaction_id, receipt_number, result_code, result_description, result_time, success) VALUES (?, ?, ?, ?, ?, ?)");
    mysqli_stmt_bind_param($stmt, "ssissi", $transactionId, $receiptNumber, $resultCode, $resultDescription, $resultTime, $success);
    mysqli_stmt_execute($stmt);
    mysqli_stmt_close($stmt);
    mysqli_close($conn);
    */

    // Respond with 200 OK to acknowledge receipt
    http_response_code(200);
    echo json_encode(["status" => "callback received"]);

} else {
    // Missing required fields
    http_response_code(400);
    echo json_encode(["error" => "Invalid callback payload"]);
}
	
?>