<?php
// Example TonPing webhook receiver. Set TONPING_WEBHOOK_SECRET, then point the
// device's webhook URL (https) at this script.
declare(strict_types=1);

require __DIR__ . '/tonping.php';

/** Your own code goes here. Keep it quick: TonPing waits 10 seconds for the answer. Throw on failure: you answer 500 and TonPing retries. */
function handle_event(array $event): void
{
    // Log only the type and id; never the secret or the whole body.
    error_log('tonping event ' . ($event['type'] ?? '?') . ' ' . ($event['event_id'] ?? '?'));
}

function request_headers(): array
{
    if (function_exists('getallheaders')) {
        $all = getallheaders();
        if (is_array($all)) {
            return $all;
        }
    }
    $out = [];
    foreach ($_SERVER as $key => $value) {
        if (strncmp($key, 'HTTP_', 5) === 0 && is_string($value)) {
            $out[str_replace('_', '-', substr($key, 5))] = $value;
        }
    }
    return $out;
}

function respond(int $code, string $text): void
{
    http_response_code($code);
    header('Content-Type: text/plain; charset=utf-8');
    echo $text;
    exit;
}

if (($_SERVER['REQUEST_METHOD'] ?? '') !== 'POST') {
    header('Allow: POST');
    respond(405, 'method not allowed');
}

$secret = (string) getenv('TONPING_WEBHOOK_SECRET');
if ($secret === '') {
    error_log('TONPING_WEBHOOK_SECRET is not set');
    respond(500, 'server not configured');
}

$rawBody = (string) file_get_contents('php://input');
$event = tonping_verify($secret, $rawBody, request_headers(), time());
if ($event === null) {
    respond(401, 'invalid signature');
}

$eventId = $event['event_id'] ?? null;
if (!is_string($eventId) || $eventId === '') {
    respond(400, 'missing event_id');
}

// Record the id only after the handler succeeds; a failure answers 500 and TonPing retries.
try {
    $code = tonping_handle_once(tonping_store_path(), $event, 'handle_event');
} catch (Throwable $e) {
    // The dedupe store is unusable (path, permissions, disk). Never answer 200 without it.
    error_log('tonping dedupe store failed: ' . $e->getMessage());
    respond(500, 'store failure');
}
respond($code, $code === 200 ? 'ok' : 'handler failed');