<?php
/**
 * includes/status_page.php
 *
 * Statusseite für Kunden (status.php): Zustand der Dienste („Komponenten“) und Meldungen zu Störungen und Wartungen.
 * Verwaltet wird sie im Mitarbeiterbereich (Adminportal → Statusseite) und über die Apps.
 */

function status_page_enabled(): bool
{
    return get_setting('status_page_enabled', '0') === '1';
}

/** Zustände einer Komponente, vom besten zum schlechtesten. Schlüssel => [Beschriftung, Farbe, Rang]. */
function status_component_states(): array
{
    return [
        'operational' => ['In Betrieb', '#157a45', 0],
        'maintenance' => ['Wartung', '#2563eb', 1],
        'degraded'    => ['Eingeschränkt', '#b45309', 2],
        'outage'      => ['Ausfall', '#dc2626', 3],
    ];
}

/** Erkennt ohne zusätzliche Einstellung Datenbank, DeskHub-API und konfigurierte Prüf-URLs. */
function status_app_connection(PDO $pdo, string $platform): array
{
    $timeoutSeconds = $platform === 'android' ? 3600 : 600;
    $timeoutMinutes = (int) ($timeoutSeconds / 60);
    $cutoff = date('Y-m-d H:i:s', time() - $timeoutSeconds);
    $deviceFilter = $platform === 'windows'
        ? "device_name LIKE 'Windows Desktop (%'"
        : "(device_name IS NULL OR device_name NOT LIKE 'Windows Desktop (%')";
    try {
        $stmt = $pdo->prepare("SELECT MAX(last_used_at) FROM mobile_api_tokens WHERE revoked_at IS NULL AND expires_at > ? AND last_used_at IS NOT NULL AND $deviceFilter");
        $stmt->execute([db_now()]);
        $lastSeen = $stmt->fetchColumn();
    } catch (Throwable $e) {
        $lastSeen = false;
    }
    $lastSeen = is_string($lastSeen) && $lastSeen !== '' ? $lastSeen : null;
    return ['online' => $lastSeen !== null && strtotime($lastSeen) >= strtotime($cutoff), 'last_seen' => $lastSeen, 'timeout_minutes' => $timeoutMinutes];
}

function status_component_monitor_target(PDO $pdo, array $component): ?array
{
    $type = (string) ($component['monitor_type'] ?? 'auto');
    $target = trim((string) ($component['monitor_target'] ?? ''));
    $category = mb_strtolower((string) ($component['category_name'] ?? ''));
    $name = mb_strtolower((string) ($component['name'] ?? ''));

    if ($type === 'manual') return null;
    if ($type === 'auto') {
        if ($target !== '') return ['type' => 'http', 'target' => $target, 'label' => 'Webadresse'];
        if (str_contains($name, 'android') || (str_contains($category, 'app') && str_contains($name, 'mobil'))) return ['type' => 'android_app', 'target' => '', 'label' => 'Android-App-Verbindung'];
        if (str_contains($name, 'windows') || str_contains($name, 'desktop') || str_contains($name, 'windows-programm')) return ['type' => 'windows_app', 'target' => '', 'label' => 'Windows-Programm-Verbindung'];
        if (str_contains($name, 'datenbank') || str_contains($name, 'database')) return ['type' => 'database', 'target' => '', 'label' => 'Datenbank'];
        if (str_contains($name, 'api') || str_contains($category, 'api')) return ['type' => 'http', 'target' => rtrim(base_url(), '/') . '/api/public/v1/health.php', 'label' => 'DeskHub-API'];
        if ((str_contains($name, 'support') || str_contains($name, 'kundenportal')) && (str_contains($category, 'web') || $category === '')) return ['type' => 'http', 'target' => rtrim(base_url(), '/') . '/index.php', 'label' => 'DeskHub-Portal'];
        if (str_contains($name, 'mail') || str_contains($category, 'e-mail')) return status_configured_mail_endpoints($pdo) ? ['type' => 'mail', 'target' => '', 'label' => 'E-Mail-Server'] : null;
        if ((str_contains($name, 'push') || str_contains($category, 'benachrichtigung')) && function_exists('fcm_configured') && fcm_configured()) return ['type' => 'fcm', 'target' => '', 'label' => 'Push-Dienst'];
        return null;
    }
    if ($type === 'database') return ['type' => 'database', 'target' => '', 'label' => 'Datenbank'];
    if ($type === 'android_app') return ['type' => 'android_app', 'target' => '', 'label' => 'Android-App-Verbindung'];
    if ($type === 'windows_app') return ['type' => 'windows_app', 'target' => '', 'label' => 'Windows-Programm-Verbindung'];
    if ($type === 'mail') return status_configured_mail_endpoints($pdo) ? ['type' => 'mail', 'target' => '', 'label' => 'E-Mail-Server'] : null;
    if ($type === 'fcm') return function_exists('fcm_configured') && fcm_configured() ? ['type' => 'fcm', 'target' => '', 'label' => 'Push-Dienst'] : null;
    if ($type === 'smtp') {
        if ($target === '') $target = trim((string) get_setting('smtp_host', '')) . ':' . ((int) get_setting('smtp_port', '587') ?: 587);
        return $target !== ':' ? ['type' => 'tcp', 'target' => $target, 'label' => 'E-Mail-Server'] : null;
    }
    if (in_array($type, ['http', 'tcp'], true) && $target !== '') return ['type' => $type, 'target' => $target, 'label' => $type === 'http' ? 'Webadresse' : 'Serververbindung'];
    return null;
}

function status_execute_component_check(PDO $pdo, array $check): array
{
    $started = microtime(true);
    $ok = false;
    $error = '';
    if ($check['type'] === 'database') {
        try { $pdo->query('SELECT 1'); $ok = true; } catch (Throwable $e) { $error = 'Datenbankabfrage fehlgeschlagen'; }
    } elseif (in_array($check['type'], ['android_app', 'windows_app'], true)) {
        $platform = $check['type'] === 'windows_app' ? 'windows' : 'android';
        $connection = status_app_connection($pdo, $platform);
        $ok = $connection['online'];
        if (!$ok) $error = $connection['last_seen'] === null
            ? 'Noch keine Verbindung von ' . ($platform === 'windows' ? 'Windows' : 'Android') . ' gemeldet'
            : 'Keine aktuelle Verbindung von ' . ($platform === 'windows' ? 'Windows' : 'Android');
    } elseif ($check['type'] === 'mail') {
        $endpoints = status_configured_mail_endpoints($pdo);
        $ok = count($endpoints) > 0;
        foreach ($endpoints as $endpoint) {
            $socket = @stream_socket_client('tcp://' . $endpoint['host'] . ':' . $endpoint['port'], $errno, $errstr, 4, STREAM_CLIENT_CONNECT);
            if (!is_resource($socket)) {
                $ok = false;
                $error = $endpoint['name'] . '-Server nicht erreichbar (' . $endpoint['host'] . ':' . $endpoint['port'] . ')';
                break;
            }
            fclose($socket);
        }
        if (!$ok && $error === '') $error = 'Kein E-Mail-Server eingerichtet';
    } elseif ($check['type'] === 'fcm') {
        $mode = function_exists('fcm_mode') ? fcm_mode() : 'none';
        if ($mode === 'own' && function_exists('fcm_service_account') && function_exists('fcm_access_token')) {
            $account = fcm_service_account();
            $ok = $account !== null && fcm_access_token($account) !== null;
            if (!$ok) $error = 'Firebase-Zugang konnte nicht bestätigt werden';
        } elseif ($mode === 'relay') {
            $url = function_exists('fcm_relay_url') ? fcm_relay_url() : '';
            $host = (string) parse_url($url, PHP_URL_HOST);
            $port = (int) (parse_url($url, PHP_URL_PORT) ?: 443);
            if ($host !== '') {
                $socket = @stream_socket_client('tcp://' . $host . ':' . $port, $errno, $errstr, 4, STREAM_CLIENT_CONNECT);
                $ok = is_resource($socket);
                if ($ok) fclose($socket); else $error = 'Push-Dienst nicht erreichbar';
            } else $error = 'Push-Dienst nicht eingerichtet';
        } else $error = 'Push-Dienst nicht eingerichtet';
    } elseif ($check['type'] === 'tcp') {
        if (preg_match('/^([a-zA-Z0-9.-]+):(\\d{1,5})$/', (string) $check['target'], $m) && (int) $m[2] > 0 && (int) $m[2] <= 65535) {
            $socket = @stream_socket_client('tcp://' . $m[1] . ':' . $m[2], $errno, $errstr, 4, STREAM_CLIENT_CONNECT);
            $ok = is_resource($socket);
            if ($ok) fclose($socket); else $error = 'Server oder Port nicht erreichbar';
        } else $error = 'Ungültiges Prüfziel';
    } elseif ($check['type'] === 'http') {
        $url = (string) $check['target'];
        if (filter_var($url, FILTER_VALIDATE_URL) && in_array(strtolower((string) parse_url($url, PHP_URL_SCHEME)), ['http', 'https'], true)) {
            if (function_exists('curl_init')) {
                $ch = curl_init($url);
                curl_setopt_array($ch, [CURLOPT_RETURNTRANSFER => false, CURLOPT_WRITEFUNCTION => static fn($handle, string $body): int => strlen($body), CURLOPT_FOLLOWLOCATION => true, CURLOPT_MAXREDIRS => 4, CURLOPT_CONNECTTIMEOUT => 4, CURLOPT_TIMEOUT => 7, CURLOPT_USERAGENT => 'DeskHub Status Check']);
                curl_exec($ch);
                $code = (int) curl_getinfo($ch, CURLINFO_RESPONSE_CODE);
                $error = curl_error($ch);
                curl_close($ch);
                $ok = $code >= 200 && $code < 400;
            } else {
                $context = stream_context_create(['http' => ['method' => 'GET', 'timeout' => 7, 'ignore_errors' => true, 'follow_location' => 1, 'max_redirects' => 4], 'ssl' => ['verify_peer' => true, 'verify_peer_name' => true]]);
                @file_get_contents($url, false, $context);
                $code = 0;
                foreach (($http_response_header ?? []) as $header) if (preg_match('/^HTTP\\/\\S+\\s+(\\d{3})/', $header, $m)) $code = (int) $m[1];
                $ok = $code >= 200 && $code < 400;
            }
            if (!$ok && $error === '') $error = 'Webseite antwortet mit HTTP ' . ($code ?: 'ohne Antwort');
        } else $error = 'Ungültige oder nicht unterstützte Prüf-URL';
    }
    return ['ok' => $ok, 'error' => mb_substr($error, 0, 255), 'ms' => (int) round((microtime(true) - $started) * 1000)];
}

function status_run_component_checks(PDO $pdo): int
{
    $components = status_components($pdo);
    $update = $pdo->prepare('UPDATE status_components SET last_checked_at = ?, last_check_ms = ?, last_check_error = ?, consecutive_failures = ? WHERE id = ?');
    $sample = $pdo->prepare('INSERT INTO status_component_checks (component_id, status, checked_at, response_ms) VALUES (?,?,?,?)');
    $checked = 0;
    foreach ($components as $component) {
        $check = status_component_monitor_target($pdo, $component);
        if ($check === null) continue;
        $result = status_execute_component_check($pdo, $check);
        $failures = $result['ok'] ? 0 : (int) ($component['consecutive_failures'] ?? 0) + 1;
        $update->execute([db_now(), $result['ms'], $result['ok'] ? null : $result['error'], $failures, (int) $component['id']]);
        $currentStatus = (string) $component['status'];
        if ($result['ok'] && $currentStatus !== 'maintenance' && $currentStatus !== 'operational') {
            status_set_component($pdo, (int) $component['id'], 'operational');
            $currentStatus = 'operational';
        } elseif (!$result['ok'] && $failures >= 2 && $currentStatus !== 'maintenance' && $currentStatus !== 'outage') {
            status_set_component($pdo, (int) $component['id'], 'outage');
            $currentStatus = 'outage';
        }
        $sample->execute([(int) $component['id'], $currentStatus, db_now(), $result['ms']]);
        $checked++;
    }
    if (function_exists('pseudo_cron_try_claim') && pseudo_cron_try_claim($pdo, 'status_check_samples_cleanup', 86400)) {
        $pdo->prepare('DELETE FROM status_component_checks WHERE checked_at < ?')->execute([date('Y-m-d H:i:s', time() - 30 * 86400)]);
    }
    return $checked;
}

/** Erkennt vorhandene automatische Prüfziele und prüft sie sofort; externe Ziele ohne URL bleiben offen. */
function status_discover_and_check(PDO $pdo): array
{
    $recognized = [];
    $pending = [];
    foreach (status_components($pdo) as $component) {
        if (($component['monitor_type'] ?? 'auto') === 'manual') continue;
        if (status_component_monitor_target($pdo, $component) !== null) $recognized[] = (string) $component['name'];
        elseif (($component['monitor_type'] ?? 'auto') === 'auto') $pending[] = (string) $component['name'];
    }
    $checked = status_run_component_checks($pdo);
    return ['recognized' => $recognized, 'pending' => $pending, 'checked' => $checked];
}

/** Stufen einer Störungsmeldung. */
function status_incident_states(): array
{
    return [
        'investigating' => 'Wird untersucht',
        'identified'    => 'Ursache gefunden',
        'monitoring'    => 'Wird beobachtet',
        'resolved'      => 'Behoben',
    ];
}

function status_components(PDO $pdo): array
{
    return $pdo->query("SELECT c.*, COALESCE(cat.name, NULLIF(c.category, '')) AS category_name FROM status_components c LEFT JOIN status_categories cat ON cat.id = c.category_id ORDER BY COALESCE(cat.sort_order, 0), COALESCE(cat.name, c.category, ''), c.sort_order, c.name")->fetchAll();
}

function status_categories(PDO $pdo): array
{
    return $pdo->query('SELECT * FROM status_categories ORDER BY sort_order, name')->fetchAll();
}

function status_monitor_types(): array
{
    return [
        'auto' => 'Automatisch erkennen',
        'http' => 'Webseite / URL',
        'android_app' => 'Android-App-Verbindung',
        'windows_app' => 'Windows-Programm-Verbindung',
        'database' => 'Datenbankverbindung',
        'smtp' => 'SMTP-Server',
        'mail' => 'E-Mail (SMTP und IMAP)',
        'fcm' => 'Push-Dienst',
        'tcp' => 'Server und Port',
        'manual' => 'Manuell verwalten',
    ];
}

/** SMTP- und IMAP-Ziele aus den eingerichteten Konten der Installation. */
function status_configured_mail_endpoints(PDO $pdo): array
{
    $targets = [];
    $globalHost = trim((string) get_setting('smtp_host', ''));
    if ($globalHost !== '') $targets[] = ['host' => $globalHost, 'port' => (int) get_setting('smtp_port', '587') ?: 587, 'name' => 'SMTP'];
    try {
        foreach ($pdo->query("SELECT smtp_host, smtp_port FROM email_addresses WHERE smtp_enabled = 1 AND is_active = 1 AND smtp_host <> ''")->fetchAll() as $row) {
            if (trim((string) $row['smtp_host']) !== '') $targets[] = ['host' => trim((string) $row['smtp_host']), 'port' => (int) ($row['smtp_port'] ?: 587), 'name' => 'SMTP'];
        }
    } catch (Throwable $e) {
        // Einzelne oder alte Installationen können andere E-Mail-Tabellen haben.
    }
    try {
        foreach ($pdo->query('SELECT host, port FROM imap_accounts WHERE is_active = 1')->fetchAll() as $row) {
            if (trim((string) $row['host']) !== '') $targets[] = ['host' => trim((string) $row['host']), 'port' => (int) ($row['port'] ?: 993), 'name' => 'IMAP'];
        }
    } catch (Throwable $e) {
        // IMAP ist optional.
    }
    $unique = [];
    foreach ($targets as $target) $unique[$target['host'] . ':' . $target['port']] = $target;
    return array_values($unique);
}

/** Zeigt die dynamisch verwendeten Prüfziele im Mitarbeiterbereich ohne Zugangsdaten an. */
function status_component_detected_targets(PDO $pdo, array $check): array
{
    if (in_array($check['type'], ['android_app', 'windows_app'], true)) {
        $platform = $check['type'] === 'windows_app' ? 'windows' : 'android';
        $label = $platform === 'windows' ? 'Windows' : 'Android';
        $connection = status_app_connection($pdo, $platform);
        if ($connection['last_seen'] === null) return ['Noch keine Verbindung von ' . $label . ' gemeldet'];
        $when = format_dt($connection['last_seen']);
        return [$connection['online'] ? 'Verbunden · letzter Kontakt ' . $when : 'Letzter Kontakt ' . $when . ' · älter als ' . (int) $connection['timeout_minutes'] . ' Minuten'];
    }
    if ($check['type'] === 'database') {
        $db = (array) (config()['db'] ?? []);
        $driver = strtolower((string) ($db['driver'] ?? ''));
        if ($driver === 'sqlite') return ['SQLite-Datenbank (lokal)'];
        if ($driver === 'mysql') {
            $host = trim((string) ($db['host'] ?? ''));
            $port = (int) ($db['port'] ?? 3306) ?: 3306;
            return [$host !== '' ? 'MySQL · ' . $host . ':' . $port : 'MySQL-Datenbank'];
        }
        return [$driver !== '' ? strtoupper($driver) . '-Datenbank' : 'Datenbankverbindung'];
    }
    if ($check['type'] === 'mail') {
        return array_map(static fn(array $endpoint): string => $endpoint['name'] . ' · ' . $endpoint['host'] . ':' . $endpoint['port'], status_configured_mail_endpoints($pdo));
    }
    if ($check['type'] === 'fcm') {
        $mode = function_exists('fcm_mode') ? fcm_mode() : 'none';
        if ($mode === 'own') return ['Firebase Cloud Messaging'];
        if ($mode === 'relay') {
            $url = function_exists('fcm_relay_url') ? fcm_relay_url() : '';
            $host = (string) parse_url($url, PHP_URL_HOST);
            $port = parse_url($url, PHP_URL_PORT);
            return [$host !== '' ? 'Push-Relay · ' . $host . ($port ? ':' . $port : '') : 'Push-Relay'];
        }
        return ['Push-Dienst'];
    }
    return [(string) ($check['target'] ?? '')];
}

function status_set_component_monitor(PDO $pdo, int $id, string $type, string $target): bool
{
    if (!isset(status_monitor_types()[$type])) return false;
    $target = trim(mb_substr($target, 0, 500));
    if ($type === 'http' && ($target === '' || !filter_var($target, FILTER_VALIDATE_URL) || !in_array(strtolower((string) parse_url($target, PHP_URL_SCHEME)), ['http', 'https'], true))) return false;
    if ($type === 'tcp' && $target !== '' && !preg_match('/^[a-zA-Z0-9.-]+:\\d{1,5}$/', $target)) return false;
    $stmt = $pdo->prepare('UPDATE status_components SET monitor_type = ?, monitor_target = ?, consecutive_failures = 0, last_check_error = NULL WHERE id = ?');
    $stmt->execute([$type, $target !== '' ? $target : null, $id]);
    return $stmt->rowCount() > 0 || (bool) $pdo->query('SELECT 1 FROM status_components WHERE id = ' . (int) $id)->fetchColumn();
}

function status_save_category(PDO $pdo, string $name): bool
{
    $name = trim(mb_substr($name, 0, 80));
    if ($name === '') return false;
    $check = $pdo->prepare('SELECT COUNT(*) FROM status_categories WHERE LOWER(name) = LOWER(?)');
    $check->execute([$name]);
    if ((int) $check->fetchColumn() > 0) return false;
    $pdo->prepare('INSERT INTO status_categories (name, sort_order) VALUES (?,?)')->execute([$name, count(status_categories($pdo)) * 10 + 10]);
    return true;
}

function status_delete_category(PDO $pdo, int $id): void
{
    $pdo->prepare('UPDATE status_components SET category_id = NULL, category = NULL WHERE category_id = ?')->execute([$id]);
    $pdo->prepare('DELETE FROM status_categories WHERE id = ?')->execute([$id]);
}

function status_set_category_order(PDO $pdo, int $id, int $sort): bool
{
    $stmt = $pdo->prepare('UPDATE status_categories SET sort_order = ? WHERE id = ?');
    $stmt->execute([$sort, $id]);
    return $stmt->rowCount() > 0 || (bool) $pdo->query('SELECT 1 FROM status_categories WHERE id = ' . (int) $id)->fetchColumn();
}

/** Gesamtzustand: der schlechteste Zustand aller Komponenten und offener Störungen. @return array{key:string,label:string,color:string} */
function status_overall(PDO $pdo): array
{
    $states = status_component_states();
    $worst = 'operational';
    foreach (status_components($pdo) as $c) {
        if (($states[$c['status']][2] ?? 0) > $states[$worst][2]) $worst = $c['status'];
    }
    // Eine offene Störung ohne zugeordnete Komponente zählt mindestens als „eingeschränkt“
    $open = (int) $pdo->query("SELECT COUNT(*) FROM status_incidents WHERE status <> 'resolved'")->fetchColumn();
    if ($open > 0 && $states[$worst][2] < $states['degraded'][2] && $worst !== 'maintenance') $worst = 'degraded';
    return ['key' => $worst, 'label' => $worst === 'operational' ? 'Alle Systeme laufen' : ($worst === 'maintenance' ? 'Wartungsarbeiten' : ($worst === 'outage' ? 'Ausfall' : 'Teilweise eingeschränkt')), 'color' => $states[$worst][1]];
}

/** Offene Störungen und die der letzten Tage (neueste zuerst), jeweils mit ihren Updates. */
function status_incidents(PDO $pdo, int $days = 14, bool $onlyOpen = false): array
{
    $since = date('Y-m-d H:i:s', time() - max(1, $days) * 86400);
    $sql = "SELECT i.*, c.name AS component_name FROM status_incidents i LEFT JOIN status_components c ON c.id = i.component_id WHERE "
        . ($onlyOpen ? "i.status <> 'resolved'" : "(i.status <> 'resolved' OR i.created_at >= ?)") . ' ORDER BY i.created_at DESC, i.id DESC LIMIT 50';
    $stmt = $pdo->prepare($sql);
    $stmt->execute($onlyOpen ? [] : [$since]);
    $rows = $stmt->fetchAll();
    $up = $pdo->prepare('SELECT * FROM status_incident_updates WHERE incident_id = ? ORDER BY created_at DESC, id DESC');
    foreach ($rows as &$r) {
        $up->execute([$r['id']]);
        $r['updates'] = $up->fetchAll();
    }
    return $rows;
}

function status_set_component(PDO $pdo, int $id, string $status): bool
{
    if (!isset(status_component_states()[$status])) return false;
    $current = $pdo->prepare('SELECT status FROM status_components WHERE id = ?');
    $current->execute([$id]);
    $previous = $current->fetchColumn();
    if ($previous === false) return false;
    $s = $pdo->prepare('UPDATE status_components SET status = ? WHERE id = ?');
    $s->execute([$status, $id]);
    if ($previous !== $status) {
        $pdo->prepare('INSERT INTO status_component_events (component_id, status, created_at) VALUES (?,?,?)')->execute([$id, $status, db_now()]);
    }
    return true;
}

function status_toggle_component_maintenance(PDO $pdo, int $id): bool
{
    $stmt = $pdo->prepare('SELECT status FROM status_components WHERE id = ?');
    $stmt->execute([$id]);
    $current = $stmt->fetchColumn();
    if ($current === false) return false;
    return status_set_component($pdo, $id, $current === 'maintenance' ? 'operational' : 'maintenance');
}

/** Letzte einzelne Prüfungen sowie Verfügbarkeit der letzten 24 Stunden. */
function status_component_timeline(PDO $pdo, int $componentId, int $checks = 30): array
{
    $checks = max(1, min(100, $checks));
    $now = time();
    $windowStart = $now - 86400;
    $priorQuery = $pdo->prepare('SELECT status, checked_at FROM status_component_checks WHERE component_id = ? AND checked_at < ? ORDER BY checked_at DESC, id DESC LIMIT 1');
    $priorQuery->execute([$componentId, date('Y-m-d H:i:s', $windowStart)]);
    $prior = $priorQuery->fetch();
    $recentQuery = $pdo->prepare('SELECT status, checked_at FROM status_component_checks WHERE component_id = ? AND checked_at >= ? AND checked_at <= ? ORDER BY checked_at, id');
    $recentQuery->execute([$componentId, date('Y-m-d H:i:s', $windowStart), date('Y-m-d H:i:s', $now)]);
    $recent = $recentQuery->fetchAll();
    $priorTime = $prior ? strtotime((string) $prior['checked_at']) : null;
    $state = $priorTime !== null && $priorTime >= $windowStart - 120 ? (string) $prior['status'] : null;
    $cursor = $state !== null ? max($windowStart, $priorTime) : $windowStart;
    $knownSeconds = 0;
    $upSeconds = 0;
    foreach ($recent as $check) {
        $checkTime = strtotime((string) $check['checked_at']);
        if ($state !== null && $checkTime > $cursor) {
            $duration = min($checkTime - $cursor, 120);
            $knownSeconds += $duration;
            if ($state === 'operational') $upSeconds += $duration;
        }
        $state = (string) $check['status'];
        $cursor = max($cursor, $checkTime);
    }
    if ($state !== null && $now > $cursor) {
        $duration = min($now - $cursor, 120);
        $knownSeconds += $duration;
        if ($state === 'operational') $upSeconds += $duration;
    }

    $barsQuery = $pdo->prepare('SELECT status, checked_at FROM status_component_checks WHERE component_id = ? ORDER BY checked_at DESC, id DESC LIMIT ' . $checks);
    $barsQuery->execute([$componentId]);
    $bars = array_reverse($barsQuery->fetchAll());
    $bars = array_map(static fn(array $bar): array => [
        'date' => date('d.m.Y H:i:s', strtotime((string) $bar['checked_at'])),
        'status' => (string) $bar['status'],
    ], $bars);
    while (count($bars) < $checks) array_unshift($bars, ['date' => '', 'status' => null]);
    return [
        'bars' => $bars,
        'uptime' => $knownSeconds > 0 ? round($upSeconds / $knownSeconds * 100, 2) : null,
    ];
}

function status_set_component_category(PDO $pdo, int $id, ?int $categoryId, int $sort): bool
{
    if ($categoryId !== null) {
        $check = $pdo->prepare('SELECT COUNT(*) FROM status_categories WHERE id = ?');
        $check->execute([$categoryId]);
        if (!(int) $check->fetchColumn()) $categoryId = null;
    }
    $stmt = $pdo->prepare('UPDATE status_components SET category_id = ?, category = NULL, sort_order = ? WHERE id = ?');
    $stmt->execute([$categoryId, $sort, $id]);
    return $stmt->rowCount() > 0 || (bool) $pdo->query('SELECT 1 FROM status_components WHERE id = ' . (int) $id)->fetchColumn();
}

function status_save_component(PDO $pdo, ?int $id, string $name, string $description, int $sort, ?int $categoryId = null): ?int
{
    $name = trim(mb_substr($name, 0, 120));
    if ($name === '') return null;
    $description = trim(mb_substr($description, 0, 255));
    if ($categoryId !== null) {
        $check = $pdo->prepare('SELECT COUNT(*) FROM status_categories WHERE id = ?');
        $check->execute([$categoryId]);
        if (!(int) $check->fetchColumn()) $categoryId = null;
    }
    if ($id) {
        $pdo->prepare('UPDATE status_components SET name = ?, description = ?, sort_order = ?, category_id = ?, category = NULL WHERE id = ?')->execute([$name, $description !== '' ? $description : null, $sort, $categoryId, $id]);
        return $id;
    }
    $pdo->prepare('INSERT INTO status_components (name, description, status, sort_order, created_at, category_id, category) VALUES (?,?,?,?,?,?,NULL)')->execute([$name, $description !== '' ? $description : null, 'operational', $sort, db_now(), $categoryId]);
    $newId = (int) $pdo->lastInsertId();
    $pdo->prepare('INSERT INTO status_component_events (component_id, status, created_at) VALUES (?,?,?)')->execute([$newId, 'operational', db_now()]);
    return $newId;
}

function status_delete_component(PDO $pdo, int $id): void
{
    $pdo->prepare('UPDATE status_incidents SET component_id = NULL WHERE component_id = ?')->execute([$id]);
    $pdo->prepare('DELETE FROM status_component_events WHERE component_id = ?')->execute([$id]);
    $pdo->prepare('DELETE FROM status_components WHERE id = ?')->execute([$id]);
}

/** Restore missing DeskHub core services without changing existing entries. */
function status_restore_core_components(PDO $pdo): int
{
    $defaults = [
        ['DeskHub-Supportportal', 'Webseite', 'auto', ['DeskHub Supportportal']],
        ['DeskHub-API', 'API-Schnittstellen', 'auto', ['DeskHub API']],
        ['Datenbank', 'Server & Datenbank', 'database', ['Datenbank Server', 'Database']],
        ['Maildienst', 'E-Mail', 'mail', ['Mail Dienst', 'Mail Server']],
        ['Push-Dienst', 'Benachrichtigungen', 'fcm', ['Push Dienst']],
        ['Android-App', 'Apps', 'android_app', ['Windelgeschichten-Android-App', 'DeskHub-Mitarbeiter-App für Android']],
        ['Windows-Programm', 'Apps', 'windows_app', ['DeskHub-Mitarbeiter-App für Windows', 'Windows-App']],
    ];
    $find = $pdo->prepare('SELECT id, category_id FROM status_components WHERE LOWER(name) = LOWER(?) LIMIT 1');
    $findCategory = $pdo->prepare('SELECT id FROM status_categories WHERE LOWER(name) = LOWER(?) LIMIT 1');
    $categoryIds = [];
    $nextCategoryOrder = (int) $pdo->query('SELECT COALESCE(MAX(sort_order), 0) FROM status_categories')->fetchColumn() + 10;
    foreach (array_unique(array_column($defaults, 1)) as $categoryName) {
        $findCategory->execute([$categoryName]);
        $categoryId = $findCategory->fetchColumn();
        if (!$categoryId) {
            $pdo->prepare('INSERT INTO status_categories (name, sort_order) VALUES (?, ?)')->execute([$categoryName, $nextCategoryOrder]);
            $categoryId = (int) $pdo->lastInsertId();
            $nextCategoryOrder += 10;
        }
        $categoryIds[$categoryName] = (int) $categoryId;
    }
    $maxOrder = (int) $pdo->query('SELECT COALESCE(MAX(sort_order), 0) FROM status_components')->fetchColumn();
    $restored = 0;
    foreach ($defaults as [$name, $categoryName, $monitorType, $aliases]) {
        $existing = null;
        foreach (array_merge([$name], $aliases) as $candidate) {
            $find->execute([$candidate]);
            $row = $find->fetch(PDO::FETCH_ASSOC);
            if ($row) { $existing = $row; break; }
        }
        $categoryId = $categoryIds[$categoryName] ?? null;
        if ($existing) {
            if (empty($existing['category_id']) && $categoryId) {
                $pdo->prepare('UPDATE status_components SET category_id = ?, category = NULL WHERE id = ?')->execute([$categoryId, (int) $existing['id']]);
            }
            continue;
        }
        $id = status_save_component($pdo, null, $name, '', $maxOrder + 10, $categoryId);
        if ($id) {
            status_set_component_monitor($pdo, $id, $monitorType, '');
            $maxOrder += 10;
            $restored++;
        }
    }
    return $restored;
}

/**
 * Neue Störungs- oder Wartungsmeldung. Mit $componentState wird die zugeordnete Komponente gleich auf diesen Zustand gesetzt.
 * @return array{ok:bool,id?:int,error?:string}
 */
function status_create_incident(PDO $pdo, string $title, string $body, string $status, ?int $componentId, ?string $componentState, ?int $staffId): array
{
    $title = trim(mb_substr($title, 0, 200));
    if ($title === '') return ['ok' => false, 'error' => 'Bitte einen Titel angeben.'];
    if (!isset(status_incident_states()[$status])) $status = 'investigating';
    if ($componentId !== null) {
        $c = $pdo->prepare('SELECT COUNT(*) FROM status_components WHERE id = ?');
        $c->execute([$componentId]);
        if (!(int) $c->fetchColumn()) $componentId = null;
    }
    $now = db_now();
    $pdo->prepare('INSERT INTO status_incidents (title, body, status, impact, component_id, created_by, created_at, updated_at, resolved_at) VALUES (?,?,?,?,?,?,?,?,?)')
        ->execute([$title, trim($body) !== '' ? trim($body) : null, $status, 'minor', $componentId, $staffId, $now, $now, $status === 'resolved' ? $now : null]);
    $id = (int) $pdo->lastInsertId();
    if (trim($body) !== '') {
        $pdo->prepare('INSERT INTO status_incident_updates (incident_id, status, body, created_by, created_at) VALUES (?,?,?,?,?)')->execute([$id, $status, trim($body), $staffId, $now]);
    }
    if ($componentId !== null && $componentState !== null && isset(status_component_states()[$componentState])) status_set_component($pdo, $componentId, $componentState);
    return ['ok' => true, 'id' => $id];
}

/**
 * Update zu einer Meldung. Wird sie als „Behoben“ markiert, setzt die zugeordnete Komponente zurück auf „In Betrieb“, wenn $restore true ist.
 * @return array{ok:bool,error?:string}
 */
function status_update_incident(PDO $pdo, int $id, string $status, string $body, ?int $staffId, bool $restore = true): array
{
    if (!isset(status_incident_states()[$status])) return ['ok' => false, 'error' => 'Unbekannter Status.'];
    $s = $pdo->prepare('SELECT * FROM status_incidents WHERE id = ?');
    $s->execute([$id]);
    $inc = $s->fetch();
    if (!$inc) return ['ok' => false, 'error' => 'Meldung nicht gefunden.'];
    $now = db_now();
    $pdo->prepare('UPDATE status_incidents SET status = ?, updated_at = ?, resolved_at = ? WHERE id = ?')
        ->execute([$status, $now, $status === 'resolved' ? ($inc['resolved_at'] ?: $now) : null, $id]);
    $pdo->prepare('INSERT INTO status_incident_updates (incident_id, status, body, created_by, created_at) VALUES (?,?,?,?,?)')
        ->execute([$id, $status, trim(mb_substr($body, 0, 4000)), $staffId, $now]);
    if ($status === 'resolved' && $restore && $inc['component_id']) {
        // Nur zurücksetzen, wenn keine andere offene Meldung dieselbe Komponente betrifft
        $o = $pdo->prepare("SELECT COUNT(*) FROM status_incidents WHERE component_id = ? AND status <> 'resolved' AND id <> ?");
        $o->execute([$inc['component_id'], $id]);
        if (!(int) $o->fetchColumn()) status_set_component($pdo, (int) $inc['component_id'], 'operational');
    }
    return ['ok' => true];
}

function status_delete_incident(PDO $pdo, int $id): void
{
    $pdo->prepare('DELETE FROM status_incident_updates WHERE incident_id = ?')->execute([$id]);
    $pdo->prepare('DELETE FROM status_incidents WHERE id = ?')->execute([$id]);
}

/** Zusammenfassung für die Apps. */
function status_summary(PDO $pdo): array
{
    $states = status_component_states();
    $overall = status_overall($pdo);
    return [
        'enabled' => status_page_enabled(),
        'title' => (string) get_setting('status_page_title', 'Systemstatus'),
        'url' => base_url() . '/status.php',
        'overall' => $overall,
        'componentStates' => array_map(fn($k, $v) => ['key' => $k, 'label' => $v[0]], array_keys($states), $states),
        'incidentStates' => array_map(fn($k, $v) => ['key' => $k, 'label' => $v], array_keys(status_incident_states()), status_incident_states()),
        'components' => array_map(fn($c) => ['id' => (int) $c['id'], 'name' => (string) $c['name'], 'description' => (string) ($c['description'] ?? ''), 'category' => (string) ($c['category_name'] ?? ''), 'categoryId' => $c['category_id'] !== null ? (int) $c['category_id'] : null, 'status' => (string) $c['status'], 'statusLabel' => $states[$c['status']][0] ?? $c['status']], status_components($pdo)),
        'incidents' => array_map(fn($i) => [
            'id' => (int) $i['id'], 'title' => (string) $i['title'], 'status' => (string) $i['status'], 'statusLabel' => status_incident_states()[$i['status']] ?? $i['status'],
            'component' => $i['component_name'] ?? null, 'componentId' => $i['component_id'] !== null ? (int) $i['component_id'] : null,
            'createdAt' => (string) $i['created_at'], 'updatedAt' => (string) $i['updated_at'], 'resolvedAt' => $i['resolved_at'],
            'updates' => array_map(fn($u) => ['status' => (string) $u['status'], 'statusLabel' => status_incident_states()[$u['status']] ?? $u['status'], 'body' => (string) ($u['body'] ?? ''), 'createdAt' => (string) $u['created_at']], $i['updates']),
        ], status_incidents($pdo, 14)),
    ];
}