<?php

/**
 * A stand-in for the Swish Handel API, for trying the payment flow locally
 * before there is an agreement and a certificate.
 *
 * It answers the payment request the way Swish does — with a
 * PaymentRequestToken header — and then calls the callback URL from the request
 * a few seconds later, carrying the callbackIdentifier back as a header just
 * like the real one. Everything downstream is real: the receiver app, the
 * callback verification, the booking.
 *
 * The only thing it cannot do is open the Swish app. The token is made up, so
 * the app would reject it — on a phone the page simply stays in the waiting
 * state until the fake callback lands, which is exactly what we want to see.
 *
 * Start it inside the kiosk container:
 *
 *   docker exec -d lan_kiosk-api-1 php -S 127.0.0.1:9099 /var/www/html/dev/fake-swish.php
 *
 * and point the app at it in .env:
 *
 *   SWISH_API_URL=http://127.0.0.1:9099
 *
 * Amounts that behave differently, so every screen can be reached:
 *
 *   13 kr  → DECLINED, the payer aborted in the app
 *   1 kr   → no callback at all, the page keeps waiting until it times out
 *   other  → PAID after DELAY_SECONDS
 *
 * Delete this directory once Swish Handel is in place.
 */

const DELAY_SECONDS = 4;

// Second mode: started in the background by the request below to deliver the
// callback after the payment request has already been answered.
if (PHP_SAPI === 'cli') {
    $payload = json_decode(base64_decode($argv[1] ?? ''), true);

    if (!$payload) {
        exit(1);
    }

    sleep(DELAY_SECONDS);

    $body = json_encode($payload['body']);

    $context = stream_context_create([
        'http' => [
            'method'        => 'POST',
            'header'        => "Content-Type: application/json\r\n"
                . 'callbackIdentifier: ' . $payload['identifier'] . "\r\n",
            'content'       => $body,
            'timeout'       => 15,
            'ignore_errors' => true,
        ],
    ]);

    $result = @file_get_contents($payload['url'], false, $context);

    file_put_contents('/tmp/fake-swish.log', sprintf(
        "[%s] callback %s -> %s\n",
        date('H:i:s'),
        $payload['url'],
        $result === false ? 'FAILED' : 'sent'
    ), FILE_APPEND);

    exit(0);
}

// First mode: the payment request itself
$request = json_decode(file_get_contents('php://input'), true) ?: [];
$amount  = (float) ($request['amount'] ?? 0);

file_put_contents('/tmp/fake-swish.log', sprintf(
    "[%s] %s %s %s\n",
    date('H:i:s'),
    $_SERVER['REQUEST_METHOD'],
    $_SERVER['REQUEST_URI'],
    json_encode($request)
), FILE_APPEND);

// Swish rejects a payment request without a payee, and so do we
if (empty($request['payeeAlias'])) {
    http_response_code(422);
    header('Content-Type: application/json');
    echo json_encode([['errorCode' => 'PA02', 'errorMessage' => 'Payee alias is missing']]);
    return;
}

$instructionUuid = basename($_SERVER['REQUEST_URI']);

header('PaymentRequestToken: FAKE' . substr($instructionUuid, 0, 12));
header('Location: http://127.0.0.1:9099/swish-cpcapi/api/v1/paymentrequests/' . $instructionUuid);
http_response_code(201);

// 1 kr means "the payer never finishes", so no callback is ever sent
if ((int) $amount === 1) {
    return;
}

$callback = [
    // Already ends in /kiosk — the app puts it there so the receiver knows where to forward
    'url'        => $request['callbackUrl'],
    'identifier' => $request['callbackIdentifier'] ?? '',
    'body'       => [
        'id'                    => $instructionUuid,
        'payeePaymentReference' => $request['payeePaymentReference'] ?? '',
        'paymentReference'      => strtoupper(bin2hex(random_bytes(16))),
        'payerAlias'            => '46701234567',
        'payeeAlias'            => $request['payeeAlias'],
        'amount'                => $amount,
        'currency'              => 'SEK',
        'message'               => $request['message'] ?? '',
        'status'                => (int) $amount === 13 ? 'DECLINED' : 'PAID',
        'errorCode'             => (int) $amount === 13 ? 'BANKIDCL' : null,
        'errorMessage'          => '',
        'dateCreated'           => date('c'),
        'datePaid'              => (int) $amount === 13 ? null : date('c'),
    ],
];

// Answer first, deliver the callback afterwards — the same order as the real thing
exec(sprintf(
    'php %s %s > /dev/null 2>&1 &',
    escapeshellarg(__FILE__),
    escapeshellarg(base64_encode(json_encode($callback)))
));