<?php
declare(strict_types=1);

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

// Only accept POST requests
if ($_SERVER['REQUEST_METHOD'] !== 'POST') {
    http_response_code(405);
    echo json_encode(['error' => 'Method Not Allowed', 'allowed' => ['POST']]);
    exit;
}

// Validate key parameter
if (!isset($_GET['key']) || empty($_GET['key'])) {
    http_response_code(400);
    echo json_encode(['error' => 'Missing key parameter']);
    exit;
}

$key = $_GET['key'];
$dataPath = __DIR__ . '/data/webhooks.json';
$maxRequestsPerWebhook = 100;

// Read and validate webhook
$fp = fopen($dataPath, 'c+');
if (!$fp) {
    http_response_code(500);
    echo json_encode(['error' => 'Internal server error']);
    exit;
}

flock($fp, LOCK_EX);
$raw = stream_get_contents($fp);
$data = json_decode($raw, true);

// Find the webhook
$webhookIndex = null;
foreach ($data['webhooks'] as $index => $webhook) {
    if ($webhook['key'] === $key) {
        $webhookIndex = $index;
        break;
    }
}

if ($webhookIndex === null) {
    flock($fp, LOCK_UN);
    fclose($fp);
    http_response_code(404);
    echo json_encode(['error' => 'Webhook not found']);
    exit;
}

// Capture request data
$request = [
    'timestamp' => date('c'),
    'method' => $_SERVER['REQUEST_METHOD'],
    'headers' => getallheaders() ?: [],
    'body' => file_get_contents('php://input')
];

// Add request to webhook
$data['webhooks'][$webhookIndex]['requests'][] = $request;

// Enforce max requests limit (FIFO - remove oldest)
if (count($data['webhooks'][$webhookIndex]['requests']) > $maxRequestsPerWebhook) {
    array_shift($data['webhooks'][$webhookIndex]['requests']);
}

// Write back to file
ftruncate($fp, 0);
rewind($fp);
fwrite($fp, json_encode($data, JSON_PRETTY_PRINT));
flock($fp, LOCK_UN);
fclose($fp);

// Return success response
http_response_code(200);
echo json_encode(['success' => true, 'message' => 'Request logged']);