<?php
error_reporting(E_ALL);
ini_set('display_errors', 0);
ini_set('log_errors', 1);
ini_set('error_log', __DIR__ . '/callback_error.log');

require __DIR__ . '/../../../config/connect.php';

header("Content-Type: application/json");

// =====================
// LOAD PUBLIC KEY
// =====================
$publicKeyString = file_get_contents(__DIR__ . '/public_key_prod.pem');
$publicKey = openssl_get_publickey($publicKeyString);

// =====================
// RAW BODY
// =====================
$rawBody = file_get_contents('php://input');
$body = json_decode($rawBody, true) ?: [];

// =====================
// HEADERS
// =====================
$headers = function_exists('getallheaders') ? getallheaders() : [];

$signature = $headers['X-Signature'] ?? $_SERVER['HTTP_X_SIGNATURE'] ?? '';
$timestamp = $headers['X-Timestamp'] ?? $_SERVER['HTTP_X_TIMESTAMP'] ?? '';
$method    = $_SERVER['REQUEST_METHOD'] ?? 'POST';

// =====================
// PATH DINAMIS (WAJIB)
// =====================
$uri  = $_SERVER['REQUEST_URI'] ?? '';
$path = parse_url($uri, PHP_URL_PATH);

// =====================
// HELPER
// =====================
function clean($v){
    return is_string($v) ? trim($v) : $v;
}

// =====================
// VALIDATE SIGNATURE
// =====================
function validateSignature($publicKey, $method, $path, $rawBody, $timestamp, $signature)
{
    $hashBody = strtolower(bin2hex(hash('sha256', $rawBody, true)));

    $stringToSign = implode(':', [
        $method,
        $path,
        $hashBody,
        $timestamp
    ]);

    file_put_contents(__DIR__.'/stringtosign.log', $stringToSign.PHP_EOL, FILE_APPEND);

    return openssl_verify(
        $stringToSign,
        base64_decode($signature),
        $publicKey,
        OPENSSL_ALGO_SHA256
    ) === 1;
}

// =====================
// VALIDASI SIGNATURE
// =====================
if (!validateSignature($publicKey, $method, $path, $rawBody, $timestamp, $signature)) {

    http_response_code(400);

    echo json_encode([
        'responseCode' => '4011100',
        'responseMessage' => 'Invalid Signature'
    ]);
    exit;
}

// =====================
// DETECT TYPE
// =====================
function detectType($path, $body){
    if (strpos($path, 'transfer-va') !== false || isset($body['virtualAccountNo'])) {
        return 'VA';
    }
    if (strpos($path, 'qris') !== false) {
        return 'QRIS';
    }
    return 'EWALLET';
}

$type = detectType($path, $body);

// =====================
// NORMALISASI
// =====================
$trxId = clean(
    $body['trxId']
    ?? $body['originalPartnerReferenceNo']
    ?? null
);

$invoiceId = clean(
    $body['paymentRequestId']
    ?? $body['referenceNo']
    ?? null
);

$amount = floatval(
    $body['paidAmount']['value']
    ?? $body['amount']['value']
    ?? 0
);

$channel = clean(
    $body['additionalInfo']['channel']
    ?? $body['ewalletType']
    ?? $type
);

// =====================
// STATUS
// =====================
$statusCode = $body['latestTransactionStatus'] ?? '00';
$status = ($statusCode === '00') ? 'PAID' : 'FAILED';

// =====================
// IDEMPOTENT (ANTI DOUBLE)
// =====================
$check = $pdo->prepare("SELECT status FROM payment_winpay WHERE trx_id = ?");
$check->execute([$trxId]);
$existing = $check->fetch(PDO::FETCH_ASSOC);

if ($existing && $existing['status'] === 'PAID') {

    echo json_encode([
        'responseCode' => '2000000',
        'responseMessage' => 'ALREADY PROCESSED'
    ]);
    exit;
}

// =====================
// UPDATE DB
// =====================
try {

    $stmt = $pdo->prepare("
        UPDATE payment_winpay
        SET 
            status = :status,
            paid_at = CASE WHEN :status = 'PAID' THEN NOW() ELSE paid_at END,
            response_callback = :callback,
            updated_at = NOW()
        WHERE trx_id = :trx_id
    ");

    $stmt->execute([
        ':status'   => $status,
        ':callback' => $rawBody,
        ':trx_id'   => $trxId
    ]);

        // =====================
    // SAVE LOG (FIXED)
    // =====================
    try {

        $stmtLog = $pdo->prepare("
            INSERT INTO payment_winpay_log (
                trx_id, type, endpoint, method,
                request_body, response_body,
                status, created_at
            ) VALUES (
                :trx_id, :type, :endpoint, :method,
                :request_body, :response_body,
                :status, NOW()
            )
        ");

        $stmtLog->execute([
            ':trx_id'        => $trxId,
            ':type'          => 'CALLBACK',
            ':endpoint'      => $path, // ini paling valid dari request
            ':method'        => $method,
            ':request_body'  => $rawBody,
            ':response_body' => json_encode([
                'status' => $status,
                'type'   => $type
            ]),
            ':status'        => $status
        ]);

    } catch (Exception $e) {
        file_put_contents(__DIR__.'/callback_log_error.log',
            date('Y-m-d H:i:s').' '.$e->getMessage().PHP_EOL,
            FILE_APPEND
        );
    }

} catch (Exception $e) {

    file_put_contents(__DIR__.'/callback_db_error.log',
        date('Y-m-d H:i:s').' '.$e->getMessage().PHP_EOL,
        FILE_APPEND
    );
}

// =====================
// RESPONSE CODE DINAMIS
// =====================
$responseCode = '2000000';

if ($type === 'QRIS') {
    $responseCode = '2005200';
    $responseMessage = 'success';
} elseif ($type === 'EWALLET') {
    $responseCode = '2005600';
    $responseMessage = 'Successful';
} elseif ($type === 'VA') {
    $responseCode = '2002500';
    $responseMessage = 'Successful';
}

// =====================
// RESPONSE
// =====================
echo json_encode([
    'responseCode' => $responseCode,
    'responseMessage' => $responseMessage
]);