NC wizard: resolve WebDAV selections by fileid and storage adapter

include/nc_connector_wizard_user_scope.inc.php

@@ -20,7 +20,7 @@ function bratonien_tools_nc_wizard_webdav_list(array $state, $path = '')
   $url = rtrim((string)$state['base_url'], '/').'/remote.php/dav/files/'.$user.'/'.implode('/', $segments);
   if (substr($url, -1) !== '/') $url .= '/';
 
-  $body = '<?xml version="1.0"?><d:propfind xmlns:d="DAV:"><d:prop><d:resourcetype/><d:displayname/></d:prop></d:propfind>';
+  $body = '<?xml version="1.0"?><d:propfind xmlns:d="DAV:" xmlns:oc="http://owncloud.org/ns"><d:prop><d:resourcetype/><d:displayname/><oc:fileid/></d:prop></d:propfind>';
   $ch = curl_init($url);
   curl_setopt_array($ch, array(
     CURLOPT_RETURNTRANSFER=>true,
@@ -45,27 +45,43 @@ function bratonien_tools_nc_wizard_webdav_list(array $state, $path = '')
   $xml = simplexml_load_string((string)$response);
   if ($xml === false) throw new RuntimeException('Nextcloud hat eine ungültige WebDAV-Antwort geliefert.');
   $xml->registerXPathNamespace('d', 'DAV:');
+  $xml->registerXPathNamespace('oc', 'http://owncloud.org/ns');
 
   $children = array();
+  $fileids = array();
+  $current_fileid = 0;
+  $base_path = (string)parse_url($url, PHP_URL_PATH);
+
   foreach ($xml->xpath('//d:response') as $item)
   {
     $item->registerXPathNamespace('d', 'DAV:');
+    $item->registerXPathNamespace('oc', 'http://owncloud.org/ns');
     $hrefs = $item->xpath('d:href');
     $collections = $item->xpath('d:propstat/d:prop/d:resourcetype/d:collection');
-    if (!$hrefs || !$collections) continue;
+    $ids = $item->xpath('d:propstat/d:prop/oc:fileid');
+    if (!$hrefs || !$collections || !$ids) continue;
 
+    $fileid = (int)trim((string)$ids[0]);
+    if ($fileid < 1) continue;
     $href = rawurldecode((string)$hrefs[0]);
     $href_path = (string)parse_url($href, PHP_URL_PATH);
-    $base_path = (string)parse_url($url, PHP_URL_PATH);
-    if (rtrim($href_path, '/') === rtrim($base_path, '/')) continue;
+
+    if (rtrim($href_path, '/') === rtrim($base_path, '/'))
+    {
+      $current_fileid = $fileid;
+      continue;
+    }
 
     $name = basename(rtrim($href_path, '/'));
     if ($name === '') continue;
     $child_path = $path === '' ? $name : $path.'/'.$name;
     $children[$child_path] = $name;
+    $fileids[$child_path] = $fileid;
   }
   natcasesort($children);
 
+  if ($current_fileid < 1) throw new RuntimeException('Nextcloud hat für das aktuelle Verzeichnis keine eindeutige Datei-ID geliefert.');
+
   $parent = '';
   if ($path !== '')
   {
@@ -74,7 +90,13 @@ function bratonien_tools_nc_wizard_webdav_list(array $state, $path = '')
     $parent = implode('/', $parts);
   }
 
-  return array('current'=>$path, 'parent'=>$parent, 'children'=>$children);
+  return array(
+    'current'=>$path,
+    'parent'=>$parent,
+    'children'=>$children,
+    'current_fileid'=>$current_fileid,
+    'fileids'=>$fileids,
+  );
 }
 
 function bratonien_tools_nc_wizard_refresh_directory_state(array &$state, $path = null)
@@ -84,7 +106,149 @@ function bratonien_tools_nc_wizard_refresh_directory_state(array &$state, $path
   $state['directory_path'] = (string)$listing['current'];
   $state['directory_parent'] = (string)$listing['parent'];
   $state['directory_children'] = (array)$listing['children'];
+  $state['directory_current_fileid'] = (int)$listing['current_fileid'];
+  $state['directory_fileids'] = (array)$listing['fileids'];
   if (!isset($state['directory_selected']) || !is_array($state['directory_selected'])) $state['directory_selected'] = array();
+  if (!isset($state['directory_selected_fileids']) || !is_array($state['directory_selected_fileids'])) $state['directory_selected_fileids'] = array();
+}
+
+function bratonien_tools_nc_wizard_generic_db_config(array $state)
+{
+  return array(
+    'host'=>(string)$state['db_host'],
+    'port'=>(string)$state['db_port'],
+    'database'=>(string)$state['db_database'],
+    'user'=>(string)$state['db_user'],
+  );
+}
+
+function bratonien_tools_nc_wizard_verify_generic_data_access(array &$state)
+{
+  $config = bratonien_tools_nc_wizard_generic_db_config($state);
+  $password = (string)$state['_db_password'];
+  if (trim((string)$config['user']) === '' || $password === '') throw new RuntimeException('Die gespeicherte Reader-Verbindung ist unvollständig.');
+
+  bratonien_tools_nc_connector_psql($config, $password, 'SELECT 1');
+  bratonien_tools_nc_connector_psql($config, $password, 'SELECT 1 FROM piwigo_connector_files LIMIT 1');
+  bratonien_tools_nc_connector_psql($config, $password, 'SELECT 1 FROM piwigo_connector_activity LIMIT 1');
+
+  $state['source_view'] = 'piwigo_connector_files';
+  $state['activity_view'] = 'piwigo_connector_activity';
+  $state['source_mode'] = 'selected-fileids';
+  $state['storages'] = array();
+  $state['storage_candidates'] = array();
+  $state['roots'] = array();
+  $state['technical_complete'] = false;
+  $state['technical_stage'] = 'mounts';
+  $state['technical_source'] = 'Generische Reader-Schnittstelle geprüft';
+  $state['technical_error'] = '';
+  $state['directory_selection_ready'] = true;
+}
+
+function bratonien_tools_nc_wizard_known_adapter($storage_id, $source_path)
+{
+  $storage_id = trim((string)$storage_id);
+  $source_path = trim((string)$source_path, '/');
+  $matches = array();
+
+  foreach (bratonien_tools_nc_connector_connections() as $connection)
+  {
+    foreach ((array)($connection['config']['storages'] ?? array()) as $storage)
+    {
+      if ((string)($storage['storage_id'] ?? '') !== $storage_id) continue;
+      $prefix = trim((string)($storage['source_prefix'] ?? ''), '/');
+      if ($prefix !== '' && $source_path !== $prefix && strpos($source_path, $prefix.'/') !== 0) continue;
+      $mount = rtrim(trim((string)($storage['local_mount'] ?? '')), '/');
+      if ($mount === '' || !is_dir($mount) || !is_readable($mount)) continue;
+      $key = $prefix.'|'.$mount;
+      $matches[$key] = array('storage_id'=>$storage_id,'source_prefix'=>$prefix,'local_mount'=>$mount);
+    }
+  }
+
+  if (!$matches) return null;
+  $max = -1;
+  foreach ($matches as $match) $max = max($max, strlen((string)$match['source_prefix']));
+  $best = array_values(array_filter($matches, function($match) use ($max) { return strlen((string)$match['source_prefix']) === $max; }));
+  return count($best) === 1 ? $best[0] : null;
+}
+
+function bratonien_tools_nc_wizard_resolve_selected_roots(array &$state)
+{
+  $selected = isset($state['directory_selected']) && is_array($state['directory_selected']) ? $state['directory_selected'] : array();
+  $selected_fileids = isset($state['directory_selected_fileids']) && is_array($state['directory_selected_fileids']) ? $state['directory_selected_fileids'] : array();
+  if (!$selected) throw new RuntimeException('Bitte mindestens ein Nextcloud-Verzeichnis auswählen.');
+
+  $ids = array();
+  foreach ($selected as $path)
+  {
+    if (!isset($selected_fileids[$path]) || (int)$selected_fileids[$path] < 1) throw new RuntimeException('Für eine Auswahl fehlt die eindeutige Nextcloud-Datei-ID. Bitte das Verzeichnis erneut auswählen.');
+    $ids[(int)$selected_fileids[$path]] = (string)$path;
+  }
+
+  $config = bratonien_tools_nc_wizard_generic_db_config($state);
+  $id_list = implode(',', array_map('intval', array_keys($ids)));
+  $rows = bratonien_tools_nc_connector_psql(
+    $config,
+    (string)$state['_db_password'],
+    "SELECT fileid::text || E'\\t' || storage_id || E'\\t' || COALESCE(source_path, '') FROM piwigo_connector_files WHERE fileid IN (".$id_list.") ORDER BY fileid"
+  );
+
+  $resolved = array();
+  foreach (preg_split('/\r\n|\r|\n/', trim($rows)) as $line)
+  {
+    if ($line === '') continue;
+    $parts = explode("\t", $line, 3);
+    if (count($parts) !== 3 || !ctype_digit($parts[0])) continue;
+    $resolved[(int)$parts[0]] = array('storage_id'=>(string)$parts[1], 'source_path'=>trim((string)$parts[2], '/'));
+  }
+
+  $roots = array();
+  $candidates = array();
+  foreach ($ids as $fileid=>$path)
+  {
+    if (!isset($resolved[$fileid])) throw new RuntimeException('Das ausgewählte Nextcloud-Verzeichnis mit Datei-ID '.$fileid.' konnte nicht mehr aufgelöst werden.');
+    $storage_id = trim((string)$resolved[$fileid]['storage_id']);
+    $source_path = trim((string)$resolved[$fileid]['source_path'], '/');
+    if ($storage_id === '') throw new RuntimeException('Nextcloud hat für Datei-ID '.$fileid.' keine Storage-ID geliefert.');
+
+    $display_name = $path === '' ? ((string)($state['display_name'] ?? '') !== '' ? (string)$state['display_name'] : 'Nextcloud') : basename($path);
+    $roots[] = array(
+      'fileid'=>(int)$fileid,
+      'display_name'=>$display_name,
+      'webdav_path'=>$path,
+      'storage_id'=>$storage_id,
+      'source_path'=>$source_path,
+    );
+
+    $adapter = bratonien_tools_nc_wizard_known_adapter($storage_id, $source_path);
+    if (!$adapter) $adapter = array('storage_id'=>$storage_id,'source_prefix'=>'','local_mount'=>'');
+    $key = $adapter['storage_id'].'|'.$adapter['source_prefix'].'|'.$adapter['local_mount'];
+    $candidates[$key] = $adapter;
+  }
+
+  $state['roots'] = array_values($roots);
+  $state['storage_candidates'] = array_values($candidates);
+  $state['storages'] = $state['storage_candidates'];
+
+  $all_mapped = !empty($state['storage_candidates']);
+  foreach ($state['storage_candidates'] as $candidate)
+  {
+    $mount = rtrim(trim((string)($candidate['local_mount'] ?? '')), '/');
+    if ($mount === '' || !is_dir($mount) || !is_readable($mount)) $all_mapped = false;
+  }
+
+  if ($all_mapped)
+  {
+    $state['technical_complete'] = true;
+    $state['technical_stage'] = 'ready';
+    $state['directory_selection_ready'] = false;
+    return;
+  }
+
+  $state['technical_complete'] = false;
+  $state['technical_stage'] = 'mounts';
+  $state['directory_selection_ready'] = false;
+  $state['mount_prompted'] = true;
 }
 
 function bratonien_tools_nc_wizard_scan_user_scoped()
@@ -135,9 +299,9 @@ function bratonien_tools_nc_wizard_scan_user_scoped()
     'users'=>array(),'can_list_users'=>false,'showcase_user'=>$resolved_username,'connection_name'=>$url_host !== '' ? $url_host : 'Nextcloud',
     'scan_message'=>'Nextcloud wurde erkannt und der Benutzerzugriff wurde bestätigt.','_password'=>$password,
     'api_status'=>'pending','api_username'=>'','api_error'=>'','db_host'=>strtolower($url_host),'db_port'=>'5432','db_database'=>'nextcloud','db_user'=>'','db_password_set'=>false,'_db_password'=>'',
-    'source_view'=>'piwigo_showcase_sources','activity_view'=>'piwigo_showcase_activity','gallery_root'=>rtrim(PHPWG_ROOT_PATH, '/').'/galleries/nextcloud',
-    'storages'=>array(),'storage_candidates'=>array(),'technical_stage'=>'auto_check','technical_source'=>'Automatische Prüfung','technical_error'=>'','technical_complete'=>false,
-    'directory_selection_ready'=>false,'directory_path'=>'','directory_parent'=>'','directory_children'=>array(),'directory_selected'=>array(),
+    'source_view'=>'piwigo_connector_files','activity_view'=>'piwigo_connector_activity','source_mode'=>'selected-fileids','gallery_root'=>rtrim(PHPWG_ROOT_PATH, '/').'/galleries/nextcloud',
+    'storages'=>array(),'storage_candidates'=>array(),'roots'=>array(),'technical_stage'=>'auto_check','technical_source'=>'Automatische Prüfung','technical_error'=>'','technical_complete'=>false,
+    'directory_selection_ready'=>false,'directory_path'=>'','directory_parent'=>'','directory_children'=>array(),'directory_current_fileid'=>0,'directory_fileids'=>array(),'directory_selected'=>array(),'directory_selected_fileids'=>array(),
     'database_prompted'=>false,'mount_prompted'=>false,
   ));
 
@@ -151,31 +315,51 @@ function bratonien_tools_nc_wizard_scan_user_scoped()
     return array('message'=>'Nextcloud wurde gefunden. Für den Datenzugriff wird eine separate Reader-Verbindung benötigt.');
   }
 
-  $known_storages = isset($state['storages']) && is_array($state['storages']) ? $state['storages'] : array();
   try
   {
-    bratonien_tools_nc_wizard_finish_data_access_for_selection($state, $known_storages);
-    if (!empty($state['directory_selection_ready']))
-    {
-      bratonien_tools_nc_wizard_refresh_directory_state($state, '');
-    }
-    else
-    {
-      $state['mount_prompted'] = true;
-    }
+    bratonien_tools_nc_wizard_verify_generic_data_access($state);
+    bratonien_tools_nc_wizard_refresh_directory_state($state, '');
   }
   catch (Throwable $e)
   {
     $state['technical_complete'] = false;
     $state['technical_stage'] = 'database_details';
     $state['database_prompted'] = true;
-    $state['technical_error'] = $e->getMessage();
+    $state['technical_error'] = $e->getMessage().' Die generischen Connector-Views müssen in Nextcloud eingerichtet sein.';
   }
   bratonien_tools_nc_wizard_store($state);
 
-  if ($state['technical_stage'] === 'database_details') return array('message'=>'Nextcloud wurde gefunden. Die bekannte Reader-Verbindung konnte noch nicht vollständig bestätigt werden.');
-  if (empty($state['directory_selection_ready'])) return array('message'=>'Nextcloud und Datenzugriff wurden bestätigt. Der technische Speicherort muss einmal bestätigt werden.');
-  return array('message'=>'Nextcloud und Datenzugriff wurden bestätigt. Jetzt können die Verzeichnisse des angemeldeten Benutzers gewählt werden.');
+  if ($state['technical_stage'] === 'database_details') return array('message'=>'Nextcloud wurde gefunden. Die generische Reader-Schnittstelle konnte noch nicht bestätigt werden.');
+  return array('message'=>'Nextcloud und generischer Datenzugriff wurden bestätigt. Jetzt können die Verzeichnisse des angemeldeten Benutzers gewählt werden.');
+}
+
+function bratonien_tools_nc_wizard_save_technical_generic()
+{
+  $state = bratonien_tools_nc_wizard_state();
+  if (empty($state['scan_ok'])) throw new RuntimeException('Bitte zuerst Nextcloud erfolgreich scannen.');
+  if (trim((string)($state['db_user'] ?? '')) === '' || (string)($state['_db_password'] ?? '') === '') bratonien_tools_nc_wizard_apply_known_database_profile($state);
+  if (trim((string)($state['db_user'] ?? '')) === '' || (string)($state['_db_password'] ?? '') === '') throw new RuntimeException('Für diese Nextcloud sind noch keine Datenbank-Reader-Zugangsdaten bekannt.');
+
+  $state['db_host'] = trim((string)($_POST['nc_wizard_db_host'] ?? $state['db_host']));
+  $state['db_port'] = (string)max(1, min(65535, (int)($_POST['nc_wizard_db_port'] ?? $state['db_port'])));
+  $state['db_database'] = trim((string)($_POST['nc_wizard_db_database'] ?? $state['db_database']));
+  if ($state['db_host'] === '' || $state['db_database'] === '') throw new RuntimeException('Die Adresse der Datenbank ist noch unvollständig.');
+
+  try
+  {
+    bratonien_tools_nc_wizard_verify_generic_data_access($state);
+    bratonien_tools_nc_wizard_refresh_directory_state($state, '');
+    bratonien_tools_nc_wizard_store($state);
+    return array('message'=>'Generischer Datenzugriff wurde erfolgreich geprüft. Jetzt können Verzeichnisse ausgewählt werden.');
+  }
+  catch (Throwable $e)
+  {
+    $state['technical_error'] = $e->getMessage();
+    $state['technical_stage'] = 'database_details';
+    $state['database_prompted'] = true;
+    bratonien_tools_nc_wizard_store($state);
+    throw $e;
+  }
 }
 
 function bratonien_tools_nc_wizard_directory_browse()
@@ -193,9 +377,13 @@ function bratonien_tools_nc_wizard_directory_add()
   $state = bratonien_tools_nc_wizard_state();
   if ((int)$state['step'] !== 2 || (string)$state['technical_stage'] !== 'mounts' || empty($state['directory_selection_ready'])) throw new RuntimeException('Die Verzeichnisauswahl ist in diesem Fenster nicht verfügbar.');
   $path = trim((string)($state['directory_path'] ?? ''), '/');
+  $fileid = (int)($state['directory_current_fileid'] ?? 0);
+  if ($fileid < 1) throw new RuntimeException('Für dieses Verzeichnis fehlt die eindeutige Nextcloud-Datei-ID.');
   $selected = isset($state['directory_selected']) && is_array($state['directory_selected']) ? $state['directory_selected'] : array();
   if (!in_array($path, $selected, true)) $selected[] = $path;
   $state['directory_selected'] = array_values($selected);
+  if (!isset($state['directory_selected_fileids']) || !is_array($state['directory_selected_fileids'])) $state['directory_selected_fileids'] = array();
+  $state['directory_selected_fileids'][$path] = $fileid;
   bratonien_tools_nc_wizard_store($state);
   return array('message'=>$path === '' ? 'Stammverzeichnis ausgewählt.' : 'Verzeichnis hinzugefügt.');
 }
@@ -207,6 +395,7 @@ function bratonien_tools_nc_wizard_directory_remove()
   $path = trim((string)($_POST['nc_wizard_directory_remove'] ?? ''), '/');
   $selected = isset($state['directory_selected']) && is_array($state['directory_selected']) ? $state['directory_selected'] : array();
   $state['directory_selected'] = array_values(array_filter($selected, function($value) use ($path) { return (string)$value !== $path; }));
+  if (isset($state['directory_selected_fileids'][$path])) unset($state['directory_selected_fileids'][$path]);
   bratonien_tools_nc_wizard_store($state);
   return array('message'=>'Verzeichnis entfernt.');
 }
@@ -216,69 +405,35 @@ function bratonien_tools_nc_wizard_save_mounts_server_side()
   $state = bratonien_tools_nc_wizard_state();
   if ((int)$state['step'] !== 2 || (string)$state['technical_stage'] !== 'mounts') throw new RuntimeException('Die Speicher-/Verzeichnisauswahl ist in diesem Fenster nicht verfügbar.');
 
-  $candidates = isset($state['storage_candidates']) && is_array($state['storage_candidates']) ? $state['storage_candidates'] : array();
-  if (!$candidates) throw new RuntimeException('Es wurden noch keine Speicherorte erkannt.');
+  if (!empty($state['directory_selection_ready']))
+  {
+    bratonien_tools_nc_wizard_resolve_selected_roots($state);
+    bratonien_tools_nc_wizard_store($state);
+    return array('message'=>!empty($state['technical_complete']) ? 'Verzeichnisse und vorhandene Storage-Adapter wurden übernommen.' : 'Verzeichnisse wurden aufgelöst. Ein neuer Storage-Adapter muss noch zugeordnet werden.');
+  }
 
+  $candidates = isset($state['storage_candidates']) && is_array($state['storage_candidates']) ? $state['storage_candidates'] : array();
+  if (!$candidates) throw new RuntimeException('Es wurden noch keine Speicherorte aus der Verzeichnisauswahl aufgelöst.');
   $mounts = isset($_POST['nc_wizard_storage_mount']) && is_array($_POST['nc_wizard_storage_mount']) ? $_POST['nc_wizard_storage_mount'] : array();
 
-  // Erstes sichtbares Fenster: technische Mount-Zuordnung bestätigen.
-  if (empty($state['directory_selection_ready']))
-  {
-    foreach ($candidates as $index=>&$candidate)
-    {
-      $mount = rtrim(trim((string)($candidate['local_mount'] ?? '')), '/');
-      if ($mount === '') $mount = rtrim(trim((string)($mounts[$index] ?? '')), '/');
-      if ($mount === '' || $mount[0] !== '/') throw new RuntimeException('Für einen Speicherort fehlt ein gültiger lokaler Pfad.');
-      if (!is_dir($mount) || !is_readable($mount)) throw new RuntimeException('Der angegebene Speicherort ist nicht vorhanden oder nicht lesbar: '.$mount);
-      $candidate['local_mount'] = $mount;
-    }
-    unset($candidate);
-
-    $state['storage_candidates'] = array_values($candidates);
-    $state['mount_prompted'] = true;
-    $state['directory_selection_ready'] = true;
-    $state['technical_complete'] = false;
-    $state['technical_stage'] = 'mounts';
-    $state['directory_path'] = '';
-    $state['directory_parent'] = '';
-    $state['directory_children'] = array();
-    $state['directory_selected'] = array();
-    bratonien_tools_nc_wizard_refresh_directory_state($state, '');
-    bratonien_tools_nc_wizard_store($state);
-    return array('message'=>'Speicherzuordnung wurde bestätigt. Jetzt können die Verzeichnisse ausgewählt werden.');
-  }
-
-  // Zweites sichtbares Fenster: Verzeichnisauswahl übernehmen.
-  $selected = isset($state['directory_selected']) && is_array($state['directory_selected']) ? $state['directory_selected'] : array();
-  if (!$selected) $selected = array('');
-  $storages = array();
-
-  foreach ($candidates as $candidate)
+  foreach ($candidates as $index=>&$candidate)
   {
     $mount = rtrim(trim((string)($candidate['local_mount'] ?? '')), '/');
+    if ($mount === '') $mount = rtrim(trim((string)($mounts[$index] ?? '')), '/');
     if ($mount === '' || $mount[0] !== '/') throw new RuntimeException('Für einen Speicherort fehlt ein gültiger lokaler Pfad.');
     if (!is_dir($mount) || !is_readable($mount)) throw new RuntimeException('Der angegebene Speicherort ist nicht vorhanden oder nicht lesbar: '.$mount);
-
-    foreach ($selected as $directory)
-    {
-      $directory = trim((string)$directory, '/');
-      if ($directory !== '' && preg_match('#(^|/)\.\.(/|$)#', $directory)) throw new RuntimeException('Ungültige Verzeichnisauswahl.');
-      $storages[] = array(
-        'storage_id'=>(string)($candidate['storage_id'] ?? ''),
-        'source_prefix'=>trim((string)($candidate['source_prefix'] ?? ''), '/'),
-        'local_mount'=>$mount,
-        'include_prefix'=>$directory,
-      );
-    }
+    $candidate['local_mount'] = $mount;
   }
+  unset($candidate);
 
-  $state['storages'] = $storages;
+  $state['storage_candidates'] = array_values($candidates);
+  $state['storages'] = $state['storage_candidates'];
   $state['technical_complete'] = true;
   $state['technical_stage'] = 'ready';
   $state['technical_error'] = '';
   $state['directory_selection_ready'] = false;
   bratonien_tools_nc_wizard_store($state);
-  return array('message'=>'Verzeichnisauswahl wurde übernommen.');
+  return array('message'=>'Storage-Adapter wurde geprüft. Die Verbindung ist technisch vollständig.');
 }
 
 function bratonien_tools_nc_wizard_select_current_user()
@@ -304,12 +459,10 @@ function bratonien_tools_nc_wizard_back()
 
   if ($step === 4)
   {
-    // Abschluss -> API
     $state['step'] = 3;
   }
   elseif ($step === 3)
   {
-    // API -> Verbindungsname
     $state['step'] = 2;
     $state['technical_complete'] = true;
     $state['technical_stage'] = 'ready';
@@ -317,7 +470,6 @@ function bratonien_tools_nc_wizard_back()
   }
   elseif (!empty($state['technical_complete']))
   {
-    // Verbindungsname -> Verzeichnisauswahl
     $state['technical_complete'] = false;
     $state['technical_stage'] = 'mounts';
     $state['directory_selection_ready'] = true;
@@ -325,36 +477,16 @@ function bratonien_tools_nc_wizard_back()
   }
   elseif ((string)($state['technical_stage'] ?? '') === 'mounts' && !empty($state['directory_selection_ready']))
   {
-    // Verzeichnisauswahl -> vorher tatsächlich sichtbares Fenster.
-    if (!empty($state['mount_prompted']))
-    {
-      $state['directory_selection_ready'] = false;
-    }
-    elseif (!empty($state['database_prompted']))
-    {
-      $state['technical_stage'] = 'database_details';
-      $state['directory_selection_ready'] = false;
-    }
-    else
-    {
-      $state['step'] = 1;
-    }
+    if (!empty($state['database_prompted'])) $state['technical_stage'] = 'database_details'; else $state['step'] = 1;
+    $state['directory_selection_ready'] = false;
   }
   elseif ((string)($state['technical_stage'] ?? '') === 'mounts')
   {
-    // Mount-Zuordnung -> Datenbankfenster, falls es sichtbar war, sonst Anmeldung.
-    if (!empty($state['database_prompted']))
-    {
-      $state['technical_stage'] = 'database_details';
-    }
-    else
-    {
-      $state['step'] = 1;
-    }
+    $state['directory_selection_ready'] = true;
+    bratonien_tools_nc_wizard_refresh_directory_state($state);
   }
   elseif ((string)($state['technical_stage'] ?? '') === 'database_details')
   {
-    // Datenbankfenster -> Anmeldung.
     $state['step'] = 1;
   }
   else