<?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],
    ];
}

/** 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 * FROM status_components ORDER BY sort_order, name')->fetchAll();
}

/** 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;
    $s = $pdo->prepare('UPDATE status_components SET status = ? WHERE id = ?');
    $s->execute([$status, $id]);
    return $s->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
{
    $name = trim(mb_substr($name, 0, 120));
    if ($name === '') return null;
    $description = trim(mb_substr($description, 0, 255));
    if ($id) {
        $pdo->prepare('UPDATE status_components SET name = ?, description = ?, sort_order = ? WHERE id = ?')->execute([$name, $description !== '' ? $description : null, $sort, $id]);
        return $id;
    }
    $pdo->prepare('INSERT INTO status_components (name, description, status, sort_order, created_at) VALUES (?,?,?,?,?)')->execute([$name, $description !== '' ? $description : null, 'operational', $sort, db_now()]);
    return (int) $pdo->lastInsertId();
}

function status_delete_component(PDO $pdo, int $id): void
{
    $pdo->prepare('UPDATE status_incidents SET component_id = NULL WHERE component_id = ?')->execute([$id]);
    $pdo->prepare('DELETE FROM status_components WHERE id = ?')->execute([$id]);
}

/**
 * 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'] ?? ''), '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)),
    ];
}