<?php
// =======================================================
// generate_signature.php
// ใช้สำหรับทดสอบสร้าง Signature ฝั่งเซิร์ฟเวอร์
// =======================================================

header("Content-Type: application/json; charset=utf-8");

// ===== ค่า Token และ SECRET (ฝั่งเซิร์ฟเวอร์) =====
$TOKEN  = "PACKBEACON2025";
$SECRET = "PackBeacon@Secure!";

// ===== timestamp (ฝั่ง Client จะต้องส่งตามนี้) =====
$timestamp = time();

// ===== สร้าง signature =====
$signature = hash_hmac("sha256", $TOKEN . $timestamp, $SECRET);

// ===== ส่งกลับให้ Client =====
echo json_encode([
    "status"    => "success",
    "token"     => $TOKEN,
    "timestamp" => $timestamp,
    "signature" => $signature,
    "example_usage" => [
        "header_token"     => $TOKEN,
        "header_timestamp" => $timestamp,
        "header_signature" => $signature
    ]
], JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE);