initial commit

LICENSE

@@ -0,0 +1,339 @@
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
+  The licenses for most software are designed to take away your
+freedom to share and change it.  By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
+software--to make sure the software is free for all its users.  This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it.  (Some other Free Software Foundation software is covered by
+the GNU Lesser General Public License instead.)  You can apply it to
+your programs, too.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
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+These restrictions translate to certain responsibilities for you if you
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+
+  For example, if you distribute copies of such a program, whether
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+source code.  And you must show them these terms so they know their
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+
+  We protect your rights with two steps: (1) copyright the software, and
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+
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+  The precise terms and conditions for copying, distribution and
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+
+                    GNU GENERAL PUBLIC LICENSE
+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+  0. This License applies to any program or other work which contains
+a notice placed by the copyright holder saying it may be distributed
+under the terms of this General Public License.  The "Program", below,
+refers to any such program or work, and a "work based on the Program"
+means either the Program or any derivative work under copyright law:
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+language.  (Hereinafter, translation is included without limitation in
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+
+Activities other than copying, distribution and modification are not
+covered by this License; they are outside its scope.  The act of
+running the Program is not restricted, and the output from the Program
+is covered only if its contents constitute a work based on the
+Program (independent of having been made by running the Program).
+Whether that is true depends on what the Program does.
+
+  1. You may copy and distribute verbatim copies of the Program's
+source code as you receive it, in any medium, provided that you
+conspicuously and appropriately publish on each copy an appropriate
+copyright notice and disclaimer of warranty; keep intact all the
+notices that refer to this License and to the absence of any warranty;
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+along with the Program.
+
+You may charge a fee for the physical act of transferring a copy, and
+you may at your option offer warranty protection in exchange for a fee.
+
+  2. You may modify your copy or copies of the Program or any portion
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+distribute such modifications or work under the terms of Section 1
+above, provided that you also meet all of these conditions:
+
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+
+    b) You must cause any work that you distribute or publish, that in
+    whole or in part contains or is derived from the Program or any
+    part thereof, to be licensed as a whole at no charge to all third
+    parties under the terms of this License.
+
+    c) If the modified program normally reads commands interactively
+    when run, you must cause it, when started running for such
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+
+These requirements apply to the modified work as a whole.  If
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+
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+
+  4. You may not copy, modify, sublicense, or distribute the Program
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+
+  5. You are not required to accept this License, since you have not
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+
+  6. Each time you redistribute the Program (or any work based on the
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+
+If any portion of this section is held invalid or unenforceable under
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+
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+to distribute software through any other system and a licensee cannot
+impose that choice.
+
+This section is intended to make thoroughly clear what is believed to
+be a consequence of the rest of this License.
+
+  8. If the distribution and/or use of the Program is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Program under this License
+may add an explicit geographical distribution limitation excluding
+those countries, so that distribution is permitted only in or among
+countries not thus excluded.  In such case, this License incorporates
+the limitation as if written in the body of this License.
+
+  9. The Free Software Foundation may publish revised and/or new versions
+of the General Public License from time to time.  Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+Each version is given a distinguishing version number.  If the Program
+specifies a version number of this License which applies to it and "any
+later version", you have the option of following the terms and conditions
+either of that version or of any later version published by the Free
+Software Foundation.  If the Program does not specify a version number of
+this License, you may choose any version ever published by the Free Software
+Foundation.
+
+  10. If you wish to incorporate parts of the Program into other free
+programs whose distribution conditions are different, write to the author
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+make exceptions for this.  Our decision will be guided by the two goals
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+of promoting the sharing and reuse of software generally.
+
+                            NO WARRANTY
+
+  11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
+FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN
+OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
+PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
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+TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE
+PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
+REPAIR OR CORRECTION.
+
+  12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
+REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
+INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
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+TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
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+PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGES.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License along
+    with this program; if not, write to the Free Software Foundation, Inc.,
+    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+Also add information on how to contact you by electronic and paper mail.
+
+If the program is interactive, make it output a short notice like this
+when it starts in an interactive mode:
+
+    Gnomovision version 69, Copyright (C) year name of author
+    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, the commands you use may
+be called something other than `show w' and `show c'; they could even be
+mouse-clicks or menu items--whatever suits your program.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the program, if
+necessary.  Here is a sample; alter the names:
+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the program
+  `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+  <signature of Ty Coon>, 1 April 1989
+  Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program into
+proprietary programs.  If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.

README.md

@@ -0,0 +1,33 @@
+# Islandora Collection Manager
+
+Provides an administrative Collection Manager for Islandora-style Drupal sites.
+
+## Features
+
+- Container autocomplete restricted to configured Islandora models.
+- Recursive, cycle-safe traversal through `field_member_of`.
+- Paged descendant results (50/page).
+- Result filtering by model.
+- Configured Drupal node Actions can be applied to selected results.
+- Administrator-selectable container models using taxonomy term `field_external_uri` values.
+
+## Configuration
+
+After enabling/updating the module:
+
+    drush updb -y
+    drush cr
+
+Configure container models at:
+
+    /admin/config/content/collection-manager
+
+Use Collection Manager at:
+
+    /admin/content/collection-manager
+
+The upgrade hook preserves the former hard-coded defaults:
+
+- Collection — http://purl.org/dc/dcmitype/Collection
+- Compound Object — http://vocab.getty.edu/aat/300242735
+- Book/Paged Content — https://schema.org/Book

composer.json

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+{
+    "name": "roblib/islandora_collection_manager",
+    "description": "Allows Actions to be run on collection members",
+    "type": "drupal-custom-module",
+    "minimum-stability": "dev",
+    "license": "GPL-2.0-or-later",
+    "require": {
+    }
+}

config/install/islandora_collection_manager.settings.yml

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+container_model_uris:
+  - 'http://purl.org/dc/dcmitype/Collection'
+  - 'http://vocab.getty.edu/aat/300242735'
+  - 'https://schema.org/Book'

config/schema/islandora_collection_manager.schema.yml

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+islandora_collection_manager.settings:
+  type: config_object
+  label: 'Islandora Collection Manager settings'
+  mapping:
+    container_model_uris:
+      type: sequence
+      label: 'Container model URIs'
+      sequence:
+        type: string
+        label: 'Model URI'

islandora_collection_manager.info.yml

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+name: 'Islandora Collection Manager'
+type: module
+description: 'Select an Islandora collection/container, browse descendants, filter by model, and execute configured node actions.'
+package: Custom
+core_version_requirement: ^10 || ^11
+dependencies:
+  - drupal:node
+  - drupal:taxonomy
+  - drupal:action

islandora_collection_manager.install

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+<?php
+
+/**
+ * @file
+ * Install/update hooks for Islandora Collection Manager.
+ */
+
+/**
+ * Add configurable container models, preserving the previous hard-coded set.
+ */
+function islandora_collection_manager_update_10003(): void {
+  $config = \Drupal::configFactory()->getEditable('islandora_collection_manager.settings');
+  if ($config->get('container_model_uris') === NULL) {
+    $config->set('container_model_uris', [
+      'http://purl.org/dc/dcmitype/Collection',
+      'http://vocab.getty.edu/aat/300242735',
+      'https://schema.org/Book',
+    ])->save();
+  }
+}

islandora_collection_manager.links.menu.yml

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+islandora_collection_manager.manager:
+  title: 'Collection Manager'
+  description: 'Browse and act on descendants of a collection/container.'
+  route_name: islandora_collection_manager.manager
+  parent: system.admin_content
+  weight: 20
+
+islandora_collection_manager.settings:
+  title: 'Collection Manager'
+  description: 'Configure Collection Manager container models.'
+  route_name: islandora_collection_manager.settings
+  parent: system.admin_config_content
+  weight: 20

islandora_collection_manager.links.task.yml

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+islandora_collection_manager.manager_tab:
+  route_name: islandora_collection_manager.manager
+  title: 'Collection Manager'
+  base_route: system.admin_content
+
+islandora_collection_manager.settings_tab:
+  route_name: islandora_collection_manager.settings
+  title: 'Settings'
+  base_route: islandora_collection_manager.settings

islandora_collection_manager.permissions.yml

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+access collection manager:
+  title: 'Access Collection Manager'
+  description: 'Select containers and browse their descendants.'
+
+administer collection manager:
+  title: 'Administer Collection Manager'
+  description: 'Configure which Islandora models can be used as containers.'
+  restrict access: true
+
+execute collection manager actions:
+  title: 'Execute actions in Collection Manager'
+  description: 'Execute configured node actions from Collection Manager results.'
+  restrict access: true

islandora_collection_manager.routing.yml

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+islandora_collection_manager.manager:
+  path: '/admin/content/collection-manager'
+  defaults:
+    _form: '\Drupal\islandora_collection_manager\Form\CollectionManagerForm'
+    _title: 'Collection Manager'
+  requirements:
+    _permission: 'access collection manager'
+
+# Drupal entity autocomplete callback used by the form.
+islandora_collection_manager.autocomplete:
+  path: '/admin/content/collection-manager/autocomplete'
+  defaults:
+    _controller: '\Drupal\islandora_collection_manager\Controller\CollectionAutocompleteController::autocomplete'
+  requirements:
+    _permission: 'access collection manager'
+
+# Configuration screen.
+islandora_collection_manager.settings:
+  path: '/admin/config/content/collection-manager'
+  defaults:
+    _form: '\Drupal\islandora_collection_manager\Form\CollectionManagerSettingsForm'
+    _title: 'Collection Manager settings'
+  requirements:
+    _permission: 'administer collection manager'

islandora_collection_manager.services.yml

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+services:
+  islandora_collection_manager.model_helper:
+    class: Drupal\islandora_collection_manager\Service\ModelHelper
+    arguments: ['@entity_type.manager', '@entity_field.manager', '@config.factory']
+
+  islandora_collection_manager.descendant_finder:
+    class: Drupal\islandora_collection_manager\Service\DescendantFinder
+    arguments: ['@entity_type.manager']

src/Controller/CollectionAutocompleteController.php

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+<?php
+
+namespace Drupal\islandora_collection_manager\Controller;
+
+use Drupal\Core\Controller\ControllerBase;
+use Drupal\Core\Entity\EntityTypeManagerInterface;
+use Drupal\islandora_collection_manager\Service\ModelHelper;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+use Symfony\Component\HttpFoundation\JsonResponse;
+use Symfony\Component\HttpFoundation\Request;
+
+/**
+ * Autocomplete callback for configured container nodes.
+ */
+class CollectionAutocompleteController extends ControllerBase {
+
+  public function __construct(
+    protected EntityTypeManagerInterface $entityTypeManagerService,
+    protected ModelHelper $modelHelper,
+  ) {}
+
+  public static function create(ContainerInterface $container): static {
+    return new static(
+      $container->get('entity_type.manager'),
+      $container->get('islandora_collection_manager.model_helper'),
+    );
+  }
+
+  public function autocomplete(Request $request): JsonResponse {
+    $q = trim((string) $request->query->get('q', ''));
+    if (mb_strlen($q) < 1) {
+      return new JsonResponse([]);
+    }
+
+    $model_tids = $this->modelHelper->getContainerModelTermIds();
+    if (!$model_tids) {
+      return new JsonResponse([]);
+    }
+
+    $storage = $this->entityTypeManagerService->getStorage('node');
+    $query = $storage->getQuery()
+      ->accessCheck(TRUE)
+      ->condition('field_model.target_id', $model_tids, 'IN')
+      ->condition('title', $q, 'CONTAINS')
+      ->sort('title')
+      ->range(0, 20);
+
+    $ids = $query->execute();
+    $matches = [];
+    foreach ($storage->loadMultiple($ids) as $node) {
+      $matches[] = [
+        'value' => $node->label() . ' (' . $node->id() . ')',
+        'label' => $node->label() . ' (' . $node->id() . ')',
+      ];
+    }
+    return new JsonResponse($matches);
+  }
+
+}

src/Form/CollectionManagerForm.php

@@ -0,0 +1,310 @@
+<?php
+
+namespace Drupal\islandora_collection_manager\Form;
+
+use Drupal\Core\Action\ActionManager;
+use Drupal\Core\Entity\EntityTypeManagerInterface;
+use Drupal\Core\Form\FormBase;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Pager\PagerManagerInterface;
+use Drupal\Core\Pager\PagerParametersInterface;
+use Drupal\islandora_collection_manager\Service\DescendantFinder;
+use Drupal\islandora_collection_manager\Service\ModelHelper;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+use Symfony\Component\HttpFoundation\RequestStack;
+
+/**
+ * Collection Manager form and paged descendant results.
+ */
+class CollectionManagerForm extends FormBase {
+
+  protected const ITEMS_PER_PAGE = 50;
+
+  public function __construct(
+    protected EntityTypeManagerInterface $entityTypeManagerService,
+    protected DescendantFinder $descendantFinder,
+    protected ModelHelper $modelHelper,
+    protected PagerManagerInterface $pagerManager,
+    protected PagerParametersInterface $pagerParameters,
+    RequestStack $request_stack,
+  ) {
+    $this->requestStack = $request_stack;
+  }
+
+  public static function create(ContainerInterface $container): static {
+    return new static(
+      $container->get('entity_type.manager'),
+      $container->get('islandora_collection_manager.descendant_finder'),
+      $container->get('islandora_collection_manager.model_helper'),
+      $container->get('pager.manager'),
+      $container->get('pager.parameters'),
+      $container->get('request_stack'),
+    );
+  }
+
+  public function getFormId(): string {
+    return 'islandora_collection_manager_form';
+  }
+
+  /**
+   * {@inheritdoc}
+   *
+   * Submission is handled by the button-specific submit handlers below.
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state): void {
+    // Intentionally empty.
+  }
+
+  public function buildForm(array $form, FormStateInterface $form_state): array {
+    $request = $this->requestStack->getCurrentRequest();
+    $collection_nid = (int) $request->query->get('collection', 0);
+    $selected_models = array_values(array_filter((array) $request->query->all('models')));
+
+    $collection_default = '';
+    if ($collection_nid) {
+      $collection = $this->entityTypeManagerService->getStorage('node')->load($collection_nid);
+      if ($collection && $this->modelHelper->nodeIsConfiguredContainer($collection)) {
+        $collection_default = $collection->label() . ' (' . $collection->id() . ')';
+      }
+      else {
+        $collection_nid = 0;
+      }
+    }
+
+    $form['collection'] = [
+      '#type' => 'textfield',
+      '#title' => $this->t('Collection / container'),
+      '#default_value' => $collection_default,
+      '#autocomplete_route_name' => 'islandora_collection_manager.autocomplete',
+      '#required' => TRUE,
+      '#description' => $this->t('Begin typing the title of a configured container.'),
+    ];
+    $form['show'] = [
+      '#type' => 'submit',
+      '#value' => $this->t('Show descendants'),
+      '#submit' => ['::submitCollection'],
+    ];
+
+    if (!$collection_nid) {
+      return $form;
+    }
+
+    $all_descendants = $this->descendantFinder->findDescendantIds($collection_nid);
+    $node_storage = $this->entityTypeManagerService->getStorage('node');
+
+    // Build the result-model filter from models actually present in descendants.
+    $available_model_tids = [];
+    if ($all_descendants) {
+      $nodes = $node_storage->loadMultiple($all_descendants);
+      foreach ($nodes as $node) {
+        if ($node->hasField('field_model')) {
+          foreach ($node->get('field_model')->getValue() as $item) {
+            if (!empty($item['target_id'])) {
+              $available_model_tids[(int) $item['target_id']] = TRUE;
+            }
+          }
+        }
+      }
+    }
+
+    $model_options = [];
+    $uri_by_tid = [];
+    foreach ($this->modelHelper->getModelTerms() as $tid => $term) {
+      if (isset($available_model_tids[(int) $tid])) {
+        $uri = $this->modelHelper->getTermExternalUri($term);
+        $model_options[$uri] = $term->label();
+        $uri_by_tid[(int) $tid] = $uri;
+      }
+    }
+    asort($model_options, SORT_NATURAL | SORT_FLAG_CASE);
+
+    $form['filters'] = [
+      '#type' => 'details',
+      '#title' => $this->t('Filter results'),
+      '#open' => !empty($selected_models),
+      '#tree' => TRUE,
+    ];
+    $form['filters']['models'] = [
+      '#type' => 'checkboxes',
+      '#title' => $this->t('Result models'),
+      '#options' => $model_options,
+      '#default_value' => $selected_models,
+      '#description' => $this->t('Leave all unchecked to show descendants of every model.'),
+    ];
+    $form['filters']['apply_filter'] = [
+      '#type' => 'submit',
+      '#value' => $this->t('Apply filter'),
+      '#submit' => ['::submitFilter'],
+    ];
+    $form['filters']['clear_filter'] = [
+      '#type' => 'submit',
+      '#value' => $this->t('Clear filter'),
+      '#submit' => ['::clearFilter'],
+      '#limit_validation_errors' => [],
+    ];
+
+    $filtered_ids = $all_descendants;
+    if ($selected_models) {
+      $selected_tids = array_fill_keys($this->modelHelper->termIdsForUris($selected_models), TRUE);
+      $filtered_ids = [];
+      foreach ($node_storage->loadMultiple($all_descendants) as $nid => $node) {
+        if (!$node->hasField('field_model')) {
+          continue;
+        }
+        foreach ($node->get('field_model')->getValue() as $item) {
+          if (isset($selected_tids[(int) ($item['target_id'] ?? 0)])) {
+            $filtered_ids[] = (int) $nid;
+            break;
+          }
+        }
+      }
+    }
+
+    $total = count($filtered_ids);
+    $pager = $this->pagerManager->createPager($total, self::ITEMS_PER_PAGE);
+    $page = $this->pagerParameters->findPage();
+    $offset = $page * self::ITEMS_PER_PAGE;
+    $page_ids = array_slice($filtered_ids, $offset, self::ITEMS_PER_PAGE);
+    $page_nodes = $node_storage->loadMultiple($page_ids);
+
+    $form['summary'] = [
+      '#markup' => '<p>' . $this->formatPlural($total, '1 matching descendant', '@count matching descendants') . '</p>',
+    ];
+
+    $header = [
+      'select' => $this->t('Select'),
+      'title' => $this->t('Title'),
+      'nid' => $this->t('Node ID'),
+      'model' => $this->t('Model'),
+      'status' => $this->t('Status'),
+    ];
+    $rows = [];
+    foreach ($page_nodes as $nid => $node) {
+      $models = [];
+      if ($node->hasField('field_model')) {
+        foreach ($node->get('field_model')->referencedEntities() as $term) {
+          $models[] = $term->label();
+        }
+      }
+      $rows[$nid] = [
+        'select' => ['data' => ['#type' => 'checkbox', '#name' => 'selected[' . $nid . ']', '#return_value' => $nid]],
+        'title' => ['data' => $node->toLink($node->label())->toRenderable()],
+        'nid' => $nid,
+        'model' => implode(', ', $models),
+        'status' => $node->isPublished() ? $this->t('Published') : $this->t('Unpublished'),
+      ];
+    }
+
+    $form['results'] = [
+      '#type' => 'table',
+      '#header' => $header,
+      '#rows' => $rows,
+      '#empty' => $this->t('No descendants match the selected model filter.'),
+    ];
+    $form['pager'] = ['#type' => 'pager'];
+
+    // Preserve the existing VBO-style configured node Action UI.
+    if ($this->currentUser()->hasPermission('execute collection manager actions')) {
+      $actions = $this->getNodeActions();
+      if ($actions) {
+        $form['bulk'] = [
+          '#type' => 'container',
+          '#tree' => TRUE,
+          '#attributes' => ['class' => ['container-inline']],
+        ];
+        $form['bulk']['action'] = [
+          '#type' => 'select',
+          '#title' => $this->t('Action'),
+          '#options' => $actions,
+          '#empty_option' => $this->t('- Select an action -'),
+        ];
+        $form['bulk']['apply'] = [
+          '#type' => 'submit',
+          '#value' => $this->t('Apply to selected'),
+          '#submit' => ['::submitAction'],
+        ];
+      }
+    }
+
+    $form['#cache']['contexts'][] = 'url.query_args:collection';
+    $form['#cache']['contexts'][] = 'url.query_args:models';
+    return $form;
+  }
+
+  public function submitCollection(array &$form, FormStateInterface $form_state): void {
+    $value = trim((string) $form_state->getValue('collection'));
+    if (!preg_match('/\((\d+)\)\s*$/', $value, $matches)) {
+      $form_state->setErrorByName('collection', $this->t('Select a container from the autocomplete list.'));
+      return;
+    }
+    $nid = (int) $matches[1];
+    $node = $this->entityTypeManagerService->getStorage('node')->load($nid);
+    if (!$node || !$this->modelHelper->nodeIsConfiguredContainer($node)) {
+      $form_state->setErrorByName('collection', $this->t('The selected node is not one of the configured container models.'));
+      return;
+    }
+    $form_state->setRedirect('islandora_collection_manager.manager', [], ['query' => ['collection' => $nid]]);
+  }
+
+  public function submitFilter(array &$form, FormStateInterface $form_state): void {
+    $request = $this->requestStack->getCurrentRequest();
+    $nid = (int) $request->query->get('collection', 0);
+    $models = array_values(array_filter($form_state->getValue(['filters', 'models']) ?? []));
+    $query = ['collection' => $nid];
+    if ($models) {
+      $query['models'] = $models;
+    }
+    $form_state->setRedirect('islandora_collection_manager.manager', [], ['query' => $query]);
+  }
+
+  public function clearFilter(array &$form, FormStateInterface $form_state): void {
+    $nid = (int) $this->requestStack->getCurrentRequest()->query->get('collection', 0);
+    $form_state->setRedirect('islandora_collection_manager.manager', [], ['query' => ['collection' => $nid]]);
+  }
+
+  public function submitAction(array &$form, FormStateInterface $form_state): void {
+    if (!$this->currentUser()->hasPermission('execute collection manager actions')) {
+      throw new \Symfony\Component\HttpKernel\Exception\AccessDeniedHttpException();
+    }
+
+    $action_id = (string) $form_state->getValue(['bulk', 'action']);
+    $selected = array_keys(array_filter((array) $form_state->getValue('selected', [])));
+    if (!$action_id || !$selected) {
+      $this->messenger()->addWarning($this->t('Select at least one result and an action.'));
+      return;
+    }
+
+    $action = $this->entityTypeManagerService->getStorage('action')->load($action_id);
+    if (!$action || $action->getType() !== 'node') {
+      $this->messenger()->addError($this->t('The selected action is not available for nodes.'));
+      return;
+    }
+
+    $nodes = $this->entityTypeManagerService->getStorage('node')->loadMultiple(array_map('intval', $selected));
+    $executed = 0;
+    foreach ($nodes as $node) {
+      if ($node->access('update', $this->currentUser())) {
+        $action->execute([$node]);
+        $executed++;
+      }
+    }
+    $this->messenger()->addStatus($this->formatPlural($executed, 'Action applied to 1 node.', 'Action applied to @count nodes.'));
+    $form_state->setRebuild();
+  }
+
+  /**
+   * Returns configured node actions keyed by config entity ID.
+   */
+  protected function getNodeActions(): array {
+    $options = [];
+    $actions = $this->entityTypeManagerService->getStorage('action')->loadMultiple();
+    foreach ($actions as $id => $action) {
+      if ($action->getType() === 'node') {
+        $options[$id] = $action->label();
+      }
+    }
+    asort($options, SORT_NATURAL | SORT_FLAG_CASE);
+    return $options;
+  }
+
+}

src/Form/CollectionManagerSettingsForm.php

@@ -0,0 +1,60 @@
+<?php
+
+namespace Drupal\islandora_collection_manager\Form;
+
+use Drupal\Core\Form\ConfigFormBase;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\islandora_collection_manager\Service\ModelHelper;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Settings form for Collection Manager.
+ */
+class CollectionManagerSettingsForm extends ConfigFormBase {
+
+  public function __construct(
+    protected ModelHelper $modelHelper,
+  ) {}
+
+  public static function create(ContainerInterface $container): static {
+    return new static($container->get('islandora_collection_manager.model_helper'));
+  }
+
+  public function getFormId(): string {
+    return 'islandora_collection_manager_settings_form';
+  }
+
+  protected function getEditableConfigNames(): array {
+    return ['islandora_collection_manager.settings'];
+  }
+
+  public function buildForm(array $form, FormStateInterface $form_state): array {
+    $options = $this->modelHelper->getModelUriOptions();
+    $configured = $this->config('islandora_collection_manager.settings')->get('container_model_uris') ?? [];
+
+    $form['container_model_uris'] = [
+      '#type' => 'checkboxes',
+      '#title' => $this->t('Container models'),
+      '#description' => $this->t('Nodes using any selected model can be chosen as the starting container in Collection Manager. Model URIs come from taxonomy term field_external_uri values.'),
+      '#options' => $options,
+      '#default_value' => $configured,
+      '#required' => TRUE,
+    ];
+
+    if (!$options) {
+      $form['container_model_uris']['#description'] = $this->t('No taxonomy terms with a populated field_external_uri field were found.');
+      $form['container_model_uris']['#required'] = FALSE;
+    }
+
+    return parent::buildForm($form, $form_state);
+  }
+
+  public function submitForm(array &$form, FormStateInterface $form_state): void {
+    $selected = array_values(array_filter($form_state->getValue('container_model_uris') ?? []));
+    $this->config('islandora_collection_manager.settings')
+      ->set('container_model_uris', $selected)
+      ->save();
+    parent::submitForm($form, $form_state);
+  }
+
+}

src/Service/DescendantFinder.php

@@ -0,0 +1,46 @@
+<?php
+
+namespace Drupal\islandora_collection_manager\Service;
+
+use Drupal\Core\Entity\EntityTypeManagerInterface;
+
+/**
+ * Finds descendants through node field_member_of relationships.
+ */
+class DescendantFinder {
+
+  public function __construct(
+    protected EntityTypeManagerInterface $entityTypeManager,
+  ) {}
+
+  /**
+   * Returns all descendant node IDs, excluding the starting node.
+   *
+   * Traversal is breadth-first and cycle-safe.
+   */
+  public function findDescendantIds(int $root_nid): array {
+    $storage = $this->entityTypeManager->getStorage('node');
+    $visited = [$root_nid => TRUE];
+    $queue = [$root_nid];
+    $descendants = [];
+
+    while ($queue) {
+      $parent_ids = array_splice($queue, 0, 100);
+      $query = $storage->getQuery()
+        ->accessCheck(TRUE)
+        ->condition('field_member_of.target_id', $parent_ids, 'IN');
+      $child_ids = array_map('intval', array_values($query->execute()));
+
+      foreach ($child_ids as $child_id) {
+        if (!isset($visited[$child_id])) {
+          $visited[$child_id] = TRUE;
+          $descendants[] = $child_id;
+          $queue[] = $child_id;
+        }
+      }
+    }
+
+    return $descendants;
+  }
+
+}

src/Service/ModelHelper.php

@@ -0,0 +1,137 @@
+<?php
+
+namespace Drupal\islandora_collection_manager\Service;
+
+use Drupal\Core\Config\ConfigFactoryInterface;
+use Drupal\Core\Entity\EntityFieldManagerInterface;
+use Drupal\Core\Entity\EntityTypeManagerInterface;
+use Drupal\taxonomy\TermInterface;
+
+/**
+ * Resolves Islandora model taxonomy terms and configured container models.
+ */
+class ModelHelper {
+
+  public function __construct(
+    protected EntityTypeManagerInterface $entityTypeManager,
+    protected EntityFieldManagerInterface $entityFieldManager,
+    protected ConfigFactoryInterface $configFactory,
+  ) {}
+
+  /**
+   * Returns all taxonomy terms that have a non-empty field_external_uri.
+   *
+   * @return array<int, \Drupal\taxonomy\TermInterface>
+   *   Terms keyed by term ID.
+   */
+  public function getModelTerms(): array {
+    $storage = $this->entityTypeManager->getStorage('taxonomy_term');
+    $ids = $storage->getQuery()
+      ->accessCheck(TRUE)
+      ->condition('vid', 'islandora_models')
+      ->exists('field_external_uri')
+      ->sort('name')
+      ->execute();
+
+    if (!$ids) {
+      return [];
+    }
+
+    $terms = $storage->loadMultiple($ids);
+    return array_filter($terms, static function ($term): bool {
+      return $term instanceof TermInterface
+        && $term->bundle() === 'islandora_models'
+        && $term->hasField('field_external_uri')
+        && !$term->get('field_external_uri')->isEmpty();
+    });
+  }
+
+  /**
+   * Returns the external URI stored on an Islandora model term.
+   *
+   * field_external_uri is normally a Link field, whose property is `uri`,
+   * but accepting `value` as a fallback keeps this compatible with sites
+   * using a plain string field.
+   */
+  public function getTermExternalUri(TermInterface $term): string {
+    if (!$term->hasField('field_external_uri')) {
+      return '';
+    }
+
+    $item = $term->get('field_external_uri')->first();
+    if (!$item) {
+      return '';
+    }
+
+    $properties = $item->getValue();
+    return trim((string) ($properties['uri'] ?? $properties['value'] ?? ''));
+  }
+
+  /**
+   * Returns model choices keyed by URI and labelled with taxonomy term name.
+   */
+  public function getModelUriOptions(): array {
+    $options = [];
+    foreach ($this->getModelTerms() as $term) {
+      $uri = $this->getTermExternalUri($term);
+      if ($uri !== '') {
+        $options[$uri] = $term->label();
+      }
+    }
+    asort($options, SORT_NATURAL | SORT_FLAG_CASE);
+    return $options;
+  }
+
+  /**
+   * Returns term IDs for a list of model URIs.
+   */
+  public function termIdsForUris(array $uris): array {
+    $wanted = array_fill_keys(array_filter(array_map('strval', $uris)), TRUE);
+    if (!$wanted) {
+      return [];
+    }
+
+    $ids = [];
+    foreach ($this->getModelTerms() as $tid => $term) {
+      $uri = $this->getTermExternalUri($term);
+      if (isset($wanted[$uri])) {
+        $ids[] = (int) $tid;
+      }
+    }
+    return $ids;
+  }
+
+  /**
+   * Returns the configured container-model URIs.
+   */
+  public function getContainerModelUris(): array {
+    $uris = $this->configFactory
+      ->get('islandora_collection_manager.settings')
+      ->get('container_model_uris') ?? [];
+    return array_values(array_filter(array_map('strval', $uris)));
+  }
+
+  /**
+   * Returns configured container model term IDs.
+   */
+  public function getContainerModelTermIds(): array {
+    return $this->termIdsForUris($this->getContainerModelUris());
+  }
+
+  /**
+   * Determines whether a node has one of the configured container models.
+   */
+  public function nodeIsConfiguredContainer($node): bool {
+    if (!$node || !$node->hasField('field_model')) {
+      return FALSE;
+    }
+    $allowed = array_fill_keys($this->getContainerModelTermIds(), TRUE);
+    foreach ($node->get('field_model')->getValue() as $item) {
+      if (isset($allowed[(int) ($item['target_id'] ?? 0)])) {
+        return TRUE;
+      }
+    }
+    return FALSE;
+  }
+
+}