<?php
require_once __DIR__ . '/../includes/bootstrap.php';
require_once __DIR__ . '/_ui.php';
$staff = require_admin_or_permission('manage_custom_fields');
$pdo = get_db();

$errors = [];

if ($_SERVER['REQUEST_METHOD'] === 'POST') {
    verify_csrf();
    $action = $_POST['action'] ?? '';

    if ($action === 'create' || $action === 'update') {
        $id = (int) ($_POST['id'] ?? 0);
        $name = trim($_POST['name'] ?? '');
        $sort = (int) ($_POST['sort_order'] ?? 0);
        $notes = trim($_POST['notes'] ?? '');
        // Einträge: eine Zeile = ein Wert; Reihenfolge der Zeilen = Sortierung, doppelte Werte entfallen
        $values = [];
        foreach (preg_split('/\R/', (string) ($_POST['items'] ?? '')) as $line) {
            $line = trim($line);
            if ($line !== '' && !in_array($line, $values, true)) $values[] = $line;
        }

        if ($name === '') $errors[] = 'Bitte einen Namen angeben.';
        $dup = $pdo->prepare('SELECT COUNT(*) FROM custom_lists WHERE LOWER(name) = LOWER(?) AND id <> ?');
        $dup->execute([$name, $id]);
        if ($dup->fetchColumn() > 0) $errors[] = 'Eine Liste mit diesem Namen existiert bereits.';

        if (!$errors) {
            if ($action === 'create') {
                $pdo->prepare('INSERT INTO custom_lists (name, sort_order, notes, created_at, updated_at) VALUES (?,?,?,?,?)')->execute([$name, $sort, $notes ?: null, db_now(), db_now()]);
                $id = (int) $pdo->lastInsertId();
                audit_log($staff['id'], "Liste erstellt: {$name}");
                flash('success', 'Liste erstellt.');
            } else {
                $pdo->prepare('UPDATE custom_lists SET name=?, sort_order=?, notes=?, updated_at=? WHERE id=?')->execute([$name, $sort, $notes ?: null, db_now(), $id]);
                audit_log($staff['id'], "Liste aktualisiert: {$name}");
                flash('success', 'Änderungen gespeichert.');
            }
            // Einträge abgleichen: Bestehende behalten (und umsortieren), neue anlegen, entfernte löschen
            $existing = $pdo->prepare('SELECT id, value FROM custom_list_items WHERE list_id = ?');
            $existing->execute([$id]);
            $byValue = array_column($existing->fetchAll(), 'id', 'value');
            $upd = $pdo->prepare('UPDATE custom_list_items SET sort_order = ? WHERE id = ?');
            $ins = $pdo->prepare('INSERT INTO custom_list_items (list_id, value, sort_order) VALUES (?,?,?)');
            foreach ($values as $i => $val) {
                if (isset($byValue[$val])) { $upd->execute([($i + 1) * 10, $byValue[$val]]); unset($byValue[$val]); }
                else $ins->execute([$id, $val, ($i + 1) * 10]);
            }
            $del = $pdo->prepare('DELETE FROM custom_list_items WHERE id = ?');
            foreach ($byValue as $itemId) $del->execute([$itemId]);
            redirect('/staff/custom_lists.php');
        }
    }

    if ($action === 'delete') {
        $id = (int) $_POST['id'];
        $pdo->prepare('DELETE FROM custom_list_items WHERE list_id = ?')->execute([$id]);
        $pdo->prepare('DELETE FROM custom_lists WHERE id = ?')->execute([$id]);
        audit_log($staff['id'], "Liste gelöscht: #{$id}");
        flash('success', 'Liste gelöscht.');
        redirect('/staff/custom_lists.php');
    }
}

$isNew    = isset($_GET['new']);
$editId   = (int) ($_GET['edit'] ?? 0);
$showForm = $isNew || $editId || ($errors && in_array($_POST['action'] ?? '', ['create', 'update'], true));

$lists = $pdo->query('SELECT l.*, (SELECT COUNT(*) FROM custom_list_items i WHERE i.list_id = l.id) AS item_count FROM custom_lists l ORDER BY l.sort_order, l.name')->fetchAll();
$editList = null; $editItems = [];
if ($editId) {
    $es = $pdo->prepare('SELECT * FROM custom_lists WHERE id = ?'); $es->execute([$editId]);
    $editList = $es->fetch() ?: null;
    $ei = $pdo->prepare('SELECT value FROM custom_list_items WHERE list_id = ? ORDER BY sort_order, value'); $ei->execute([$editId]);
    $editItems = $ei->fetchAll(PDO::FETCH_COLUMN);
}

$pageTitle = 'Benutzerdefinierte Listen'; $activePage = 'custom_lists';
require __DIR__ . '/_header.php';
?>

<?php foreach ($errors as $err): ?><div class="flash error"><?= e($err) ?></div><?php endforeach; ?>

<?php if ($showForm): ?>
<?php
  $f = fn(string $k, $default = '') => $_POST[$k] ?? $default;
  $v = fn(string $k, string $col, $default = '') => $f($k, $editList[$col] ?? $default);
?>
<h1>
  <?= $editList ? 'Liste aktualisieren' : 'Neue Liste' ?>
  <?php if ($editList): ?><span class="muted" style="font-size:1rem;font-weight:400">— <?= e($editList['name']) ?></span><?php endif; ?>
</h1>

<form method="post" class="card" style="padding:0">
  <?= csrf_field() ?>
  <input type="hidden" name="action" value="<?= $editList ? 'update' : 'create' ?>">
  <?php if ($editList): ?><input type="hidden" name="id" value="<?= (int) $editList['id'] ?>"><?php endif; ?>

  <?php ui_tab_bar(['list' => 'Liste', 'items' => 'Einträge']); ?>

  <div class="tab-pane" data-pane="list" style="padding:16px 20px">
    <h3 style="margin-top:0">Listeninformationen</h3>
    <label for="name">Name *</label>
    <input type="text" id="name" name="name" value="<?= e($v('name', 'name')) ?>" placeholder="z. B. Betriebssysteme" required>
    <label for="sort_order">Sortierung</label>
    <input type="number" id="sort_order" name="sort_order" value="<?= e((string) $v('sort_order', 'sort_order', '0')) ?>" style="max-width:140px">
    <h3>Administratornotizen <span class="muted" style="font-weight:400;font-size:.85rem">– Interne Notizen, sichtbar für alle Administratoren</span></h3>
    <textarea name="notes" rows="5"><?= e($v('notes', 'notes')) ?></textarea>
    <p class="muted" style="font-size:.82rem">Wiederverwendbare Auswahllisten für Ticket-Felder: Wähle in einem <a href="/staff/custom_fields.php">Ticket-Feld</a> den Typ „Liste“ und verknüpfe diese Liste.</p>
  </div>

  <div class="tab-pane" data-pane="items" style="padding:16px 20px;display:none">
    <label for="items" style="margin-top:0">Einträge – ein Wert pro Zeile, die Reihenfolge entspricht der Anzeige</label>
    <textarea id="items" name="items" rows="14" style="font-family:monospace"><?= e($_POST ? (string) ($_POST['items'] ?? '') : implode("\n", $editItems)) ?></textarea>
    <p class="muted" style="font-size:.78rem">Entfernte Zeilen werden gelöscht, bereits in Tickets gespeicherte Werte bleiben dort unverändert sichtbar.</p>
  </div>

  <div class="btn-row" style="padding:0 20px 18px">
    <button type="submit" class="btn"><?= $editList ? 'Änderungen speichern' : 'Erstellen' ?></button>
    <a href="/staff/custom_lists.php" class="btn secondary">Abbrechen</a>
  </div>
</form>
<?php ui_tab_assets('list'); ?>

<?php else: ?>
<div style="display:flex;justify-content:space-between;align-items:center;gap:12px">
  <h1 style="margin:0">Benutzerdefinierte Listen</h1>
  <a href="/staff/custom_lists.php?new=1" class="btn">Neue Liste hinzufügen</a>
</div>
<p class="muted">Wiederverwendbare Auswahllisten für Ticket-Felder. Wähle in einem Ticket-Feld den Typ „Liste“ und verknüpfe eine dieser Listen.</p>

<div class="card">
  <table>
    <thead><tr><th>Name</th><th style="text-align:center">Einträge</th><th>Erstellt</th><th>Zuletzt aktualisiert</th><th></th></tr></thead>
    <tbody>
      <?php foreach ($lists as $l): ?>
        <tr>
          <td><a href="/staff/custom_lists.php?edit=<?= (int) $l['id'] ?>"><?= e($l['name']) ?></a></td>
          <td style="text-align:center"><?= (int) $l['item_count'] ?></td>
          <td class="muted" style="font-size:.82rem"><?= e(ui_date($l['created_at'] ?? null)) ?></td>
          <td class="muted" style="font-size:.82rem"><?= e(ui_date($l['updated_at'] ?? null)) ?></td>
          <td style="white-space:nowrap">
            <a href="/staff/custom_lists.php?edit=<?= (int) $l['id'] ?>">Bearbeiten</a> ·
            <form method="post" style="display:inline" onsubmit="return confirm('Liste wirklich löschen?')">
              <?= csrf_field() ?>
              <input type="hidden" name="action" value="delete">
              <input type="hidden" name="id" value="<?= (int) $l['id'] ?>">
              <button type="submit" style="background:none;border:none;color:#dc2626;cursor:pointer;padding:0;font-size:.9rem">Löschen</button>
            </form>
          </td>
        </tr>
      <?php endforeach; ?>
      <?php if (!$lists): ?><tr><td colspan="5" class="muted">Noch keine Listen angelegt.</td></tr><?php endif; ?>
    </tbody>
  </table>
</div>
<?php endif; ?>
<?php require __DIR__ . '/_footer.php'; ?>