<?php
/**
 * includes/ticket_extras.php
 *
 * Wiedervorlage (Ticket "auf später legen"), Beobachter (Mitarbeiter verfolgen ein Ticket, ohne es zugewiesen zu haben),
 * ähnliche Tickets und Artikel sowie die Erinnerung an Kunden vor dem automatischen Schließen.
 */

// ── Wiedervorlage ────────────────────────────────────────────────────────────

/** Auswahl im Dialog "Wiedervorlage" (Schlüssel => Beschriftung). */
function ticket_snooze_options(): array
{
    return ['1h' => 'In 1 Stunde', '3h' => 'In 3 Stunden', 'tomorrow' => 'Morgen früh (8:00 Uhr)', '3d' => 'In 3 Tagen', '1w' => 'In 1 Woche', 'custom' => 'Zu einem Zeitpunkt …'];
}

/** Rechnet die Auswahl in einen Zeitpunkt um (Y-m-d H:i:s); null, wenn ungültig oder nicht in der Zukunft (höchstens 1 Jahr). */
function ticket_snooze_until(string $choice, string $custom = ''): ?string
{
    $now = time();
    $ts = match ($choice) {
        '1h' => $now + 3600,
        '3h' => $now + 3 * 3600,
        'tomorrow' => (int) strtotime('tomorrow 08:00'),
        '3d' => $now + 3 * 86400,
        '1w' => $now + 7 * 86400,
        'custom' => $custom !== '' ? (int) strtotime(str_replace('T', ' ', $custom)) : 0,
        default => 0,
    };
    if ($ts <= $now + 30 || $ts > $now + 366 * 86400) return null;
    return date('Y-m-d H:i:s', $ts);
}

function ticket_snooze_set(PDO $pdo, int $ticketId, int $staffId, string $until): void
{
    $now = db_now();
    $pdo->prepare('UPDATE tickets SET snoozed_until = ?, snoozed_by = ?, updated_at = updated_at WHERE id = ?')->execute([$until, $staffId, $ticketId]);
    log_activity($pdo, $ticketId, $staffId, 'Wiedervorlage bis ' . date('d.m.Y H:i', (int) strtotime($until)) . ' Uhr');
}

function ticket_snooze_clear(PDO $pdo, int $ticketId, ?int $staffId, string $reason): void
{
    $stmt = $pdo->prepare('UPDATE tickets SET snoozed_until = NULL, snoozed_by = NULL WHERE id = ? AND snoozed_until IS NOT NULL');
    $stmt->execute([$ticketId]);
    if ($stmt->rowCount() > 0) log_activity($pdo, $ticketId, $staffId, $reason);
}

/** Gibt es die Spalte der Wiedervorlage schon? (Solange die Datenbank nicht aktualisiert ist, bleiben die Listen trotzdem benutzbar.) */
function ticket_snooze_available(): bool
{
    static $ok = null;
    if ($ok === null) {
        try { get_db()->query('SELECT snoozed_until FROM tickets LIMIT 1'); $ok = true; } catch (Throwable $e) { $ok = false; }
    }
    return $ok;
}

/** SQL-Bedingung: Ticket ist gerade nicht in der Wiedervorlage (für Listen und Zähler). */
function ticket_not_snoozed_sql(string $alias = 't'): string
{
    if (!ticket_snooze_available()) return '1=1';
    return "({$alias}.snoozed_until IS NULL OR {$alias}.snoozed_until <= '" . db_now() . "')";
}

/**
 * Holt fällige Wiedervorlagen zurück: Das Ticket erscheint wieder in den Listen, der Mitarbeiter bekommt eine Benachrichtigung.
 *
 * @return int Anzahl der zurückgeholten Tickets
 */
function ticket_snooze_wake_due(PDO $pdo): int
{
    try {
        $stmt = $pdo->prepare('SELECT * FROM tickets WHERE snoozed_until IS NOT NULL AND snoozed_until <= ?');
        $stmt->execute([db_now()]);
        $due = $stmt->fetchAll();
    } catch (Throwable $e) {
        return 0;   // Spalte fehlt (Datenbank noch nicht aktualisiert)
    }
    $woken = 0;
    foreach ($due as $t) {
        // Erledigte Tickets (gelöst oder geschlossen) brauchen keine Wiedervorlage mehr: still aufräumen, keine Benachrichtigung
        if (in_array((string) $t['status'], ['resolved', 'closed'], true)) {
            $pdo->prepare('UPDATE tickets SET snoozed_until = NULL, snoozed_by = NULL WHERE id = ?')->execute([$t['id']]);
            continue;
        }
        $woken++;
        $pdo->prepare('UPDATE tickets SET snoozed_until = NULL, snoozed_by = NULL, updated_at = ? WHERE id = ?')->execute([db_now(), $t['id']]);
        log_activity($pdo, (int) $t['id'], null, 'Wiedervorlage fällig');
        $to = (int) ($t['snoozed_by'] ?: ($t['assigned_staff_id'] ?? 0));
        if ($to > 0) {
            fcm_notify_staff([$to], fcm_data('ticket_snooze', $t), (int) $t['department_id']);
            if (file_exists(__DIR__ . '/push.php')) {
                require_once __DIR__ . '/push.php';
                push_to_staff($to, 'Wiedervorlage: #' . $t['ticket_number'], mb_strimwidth((string) $t['subject'], 0, 60, '…'), '/staff/ticket_view.php?n=' . urlencode((string) $t['ticket_number']));
            }
        }
    }
    return $woken;
}

// ── Beobachter ───────────────────────────────────────────────────────────────

function ticket_follow(PDO $pdo, int $ticketId, int $staffId): void
{
    $c = $pdo->prepare('SELECT COUNT(*) FROM ticket_followers WHERE ticket_id = ? AND staff_id = ?');
    $c->execute([$ticketId, $staffId]);
    if ((int) $c->fetchColumn() === 0) {
        $pdo->prepare('INSERT INTO ticket_followers (ticket_id, staff_id, created_at) VALUES (?,?,?)')->execute([$ticketId, $staffId, db_now()]);
    }
}

function ticket_unfollow(PDO $pdo, int $ticketId, int $staffId): void
{
    $pdo->prepare('DELETE FROM ticket_followers WHERE ticket_id = ? AND staff_id = ?')->execute([$ticketId, $staffId]);
}

/** @return array<int,array{id:int,name:string}> */
function ticket_followers(PDO $pdo, int $ticketId): array
{
    try {
        $stmt = $pdo->prepare('SELECT s.id, s.name FROM ticket_followers f JOIN staff s ON s.id = f.staff_id WHERE f.ticket_id = ? AND s.is_active = 1 ORDER BY s.name');
        $stmt->execute([$ticketId]);
        return $stmt->fetchAll();
    } catch (Throwable $e) {
        return [];
    }
}

/**
 * Benachrichtigt die Beobachter eines Tickets (nicht den, der es ausgelöst hat, und nicht den zugewiesenen Mitarbeiter, der ohnehin
 * Bescheid bekommt). $what ist ein kurzer Text wie "Neue Kundenantwort".
 */
function ticket_followers_notify(array $ticket, string $what, ?int $actorId = null): void
{
    if (empty($ticket['id'])) return;
    $pdo = get_db();
    $ids = array_map(fn($f) => (int) $f['id'], ticket_followers($pdo, (int) $ticket['id']));
    $skip = array_filter([$actorId, (int) ($ticket['assigned_staff_id'] ?? 0)]);
    $ids = array_values(array_diff($ids, $skip));
    if (!$ids) return;
    $data = fcm_data('ticket_follow', $ticket);
    $data['body'] = $what . ' · #' . ($ticket['ticket_number'] ?? '');
    fcm_notify_staff($ids, $data, (int) ($ticket['department_id'] ?? 0));
    if (file_exists(__DIR__ . '/push.php')) {
        require_once __DIR__ . '/push.php';
        foreach ($ids as $id) {
            push_to_staff($id, 'Beobachtet: #' . ($ticket['ticket_number'] ?? ''), $what, '/staff/ticket_view.php?n=' . urlencode((string) ($ticket['ticket_number'] ?? '')));
        }
    }
}

// ── Ähnliche Tickets und Artikel ─────────────────────────────────────────────

/**
 * Passende Artikel der Wissensdatenbank und bereits gelöste, ähnliche Tickets zu Betreff (und Kundentext) eines Tickets.
 *
 * @param int[]|null $deptIds sichtbare Abteilungen des Mitarbeiters (null = alle)
 * @return array{articles:array,tickets:array}
 */
function ticket_similar(PDO $pdo, array $ticket, ?array $deptIds = null, int $limit = 4): array
{
    require_once __DIR__ . '/assistant.php';
    $q = assistant_tokens((string) ($ticket['subject'] ?? ''));
    $out = ['articles' => [], 'tickets' => []];
    if (count($q) < 1) return $out;
    $need = max(1, (int) ceil(count($q) / 2));

    foreach ($pdo->query('SELECT id, title, slug, body FROM kb_articles WHERE is_published = 1 ORDER BY id DESC LIMIT 500')->fetchAll() as $a) {
        $title = array_flip(assistant_tokens($a['title']));
        $body = array_flip(assistant_tokens(mb_substr(strip_tags((string) $a['body']), 0, 20000)));
        $score = 0.0; $hit = 0;
        foreach ($q as $t) {
            if (isset($title[$t])) { $score += 4; $hit++; }
            elseif (isset($body[$t])) { $score += 1.5; $hit++; }
        }
        if ($hit >= $need && $score >= 2.5) $out['articles'][] = ['score' => $score, 'title' => $a['title'], 'url' => '/kb_article.php?slug=' . rawurlencode((string) $a['slug'])];
    }
    usort($out['articles'], fn($a, $b) => $b['score'] <=> $a['score']);
    $out['articles'] = array_slice($out['articles'], 0, 3);

    $sql = "SELECT id, ticket_number, subject, status FROM tickets WHERE id <> ? AND is_spam = 0 AND status IN ('resolved','closed')";
    $params = [(int) $ticket['id']];
    if ($deptIds !== null) {
        if (!$deptIds) return $out;
        $sql .= ' AND department_id IN (' . implode(',', array_fill(0, count($deptIds), '?')) . ')';
        array_push($params, ...$deptIds);
    }
    $stmt = $pdo->prepare($sql . ' ORDER BY id DESC LIMIT 800');
    $stmt->execute($params);
    foreach ($stmt->fetchAll() as $t) {
        $words = array_flip(assistant_tokens((string) $t['subject']));
        $hit = 0;
        foreach ($q as $w) if (isset($words[$w])) $hit++;
        if ($hit >= max(2, $need) || ($hit >= 1 && count($q) === 1)) $out['tickets'][] = ['score' => $hit, 'number' => $t['ticket_number'], 'subject' => $t['subject'], 'status' => $t['status']];
    }
    usort($out['tickets'], fn($a, $b) => $b['score'] <=> $a['score']);
    $out['tickets'] = array_slice($out['tickets'], 0, $limit);
    return $out;
}

// ── Erinnerung an Kunden ─────────────────────────────────────────────────────

function customer_reminder_enabled(): bool
{
    return get_setting('remind_enabled', '0') === '1';
}

function customer_reminder_days(): int
{
    return max(1, min(60, (int) get_setting('remind_after_days', '3')));
}