<?php

namespace Drupal\islandora_batch_action\Commands;

use Drupal\node\Entity\Node;
use Drush\Commands\DrushCommands;
use Drupal\Core\Entity\EntityTypeManagerInterface;
use Drupal\Core\Database\Connection;

/**
 * Provides Drush commands for batch actions on nodes.
 */
class BatchActionCommands extends DrushCommands {

  protected $entityTypeManager;
  protected $database;

  /**
   * Constructs the BatchActionCommands object.
   *
   * @param \Drupal\Core\Entity\EntityTypeManagerInterface $entity_type_manager
   *   The entity type manager service.
   * @param \Drupal\Core\Database\Connection $database
   *   The database connection.
   */
  public function __construct(EntityTypeManagerInterface $entity_type_manager, Connection $database) {
    $this->entityTypeManager = $entity_type_manager;
    $this->database = $database;
  }

  /**
   * Runs a batch action on a list of nodes.
   *
   * @command batch:action
   * @param string $action_id
   *   The machine name of the action to run.
   *
   * @usage drush batch:action my_custom_action
   */
  public function runBatchAction($action_id) {
    $action = $this->entityTypeManager->getStorage("action")->load($action_id);

    if (!$action) {
      $this->logger()->error("Action not found: $action_id");
      return;
    }

    $node_ids = $this->generateNodeList();

    if (empty($node_ids)) {
      $this->logger()->notice("No nodes found to process.");
      return;
    }

    $batch = [
      'title' => t('Running action on nodes'),
      'operations' => [],
      'finished' => [__CLASS__, 'batchFinished'],
    ];

    foreach ($node_ids as $nid) {
      $batch['operations'][] = [
        [__CLASS__, 'processNode'],
        [$nid, $action_id],
      ];
    }

    batch_set($batch);
    drush_backend_batch_process();
  }

  /**
   * Generates a list of node IDs that do not have 'Intermediate File' media.
   *
   * @return array
   *   An array of node IDs.
   */

  /**
   * Generates a list of node IDs that do not have 'Intermediate File' media
   * but have the model field set to 'Image'.
   *
   * @return array
   *   An array of node IDs.
   */

  /**
   * Generates a list of node IDs that do not have 'Intermediate File' media
   * but have the model field set to 'Image'.
   *
   * @return array
   *   An array of node IDs.
   */
  protected function generateNodeList() {
    // Subquery to get the TID for the term 'Image'.
    $image_tid_query = $this->database->select('taxonomy_term_field_data', 't')
      ->fields('t', ['tid'])
      ->condition('t.name', 'Image')
      ->condition('t.vid', 'islandora_models')
      ->execute()
      ->fetchField();

    if (!$image_tid_query) {
      $this->logger()->error("Taxonomy term 'Image' not found.");
      return [];
    }
    $this->logger()->notice("Taxonomy term 'Image' is $image_tid_query.");
    // Subquery to get nids with 'Intermediate File' media.
    $subquery = $this->database->select('node', 'n')
      ->fields('n', ['nid']);

    $subquery->innerJoin('media__field_media_of', 'mo', 'n.nid = mo.field_media_of_target_id');
    $subquery->innerJoin('media__field_media_use', 'mu', 'mu.entity_id = mo.entity_id');
    $subquery->innerJoin('taxonomy_term_field_data', 't', 'mu.field_media_use_target_id = t.tid');
    $subquery->condition('t.name', 'Intermediate File');

    // Main query to get all nids excluding the subquery result,
    // and where field_model_target_id is equal to the TID of 'Image' using EXISTS.
    $query = $this->database->select('node', 'n')
      ->fields('n', ['nid'])
      ->condition('n.nid', $subquery, 'NOT IN');

    // Adding the EXISTS condition for field_model_target_id.
    $query->exists(
    $this->database->select('node__field_model', 'fm')
      ->fields('fm', ['entity_id'])
      ->condition('fm.entity_id', 'n.nid', '=')
      ->condition('fm.field_model_target_id', $image_tid_query)
    );

    return $query->execute()->fetchCol();
  }

  /**
   * Processes an individual node in the batch.
   *
   * @param int $nid
   *   The node ID.
   * @param string $action_id
   *   The action ID.
   * @param array $context
   *   The batch context.
   */
  public static function processNode($nid, $action_id, array &$context) {
    $node = Node::load($nid);
    $action = \Drupal::entityTypeManager()->getStorage("action")->load($action_id);

    if (!$node) {
      $context['results']['errors'][] = "Node not found: $nid";
      return;
    }

    if (!$action) {
      $context['results']['errors'][] = "Action not found: $action_id";
      return;
    }

    try {
      $action->execute([$node]);
      $context['results']['processed'][] = "Processed action on node $nid";
    }
    catch (\Exception $e) {
      $context['results']['errors'][] = "Error processing node $nid: " . $e->getMessage();
    }
  }

  /**
   * Callback for batch finished.
   *
   * @param bool $success
   *   Whether the batch completed successfully.
   * @param array $results
   *   An array of results.
   * @param array $operations
   *   The list of operations.
   */
  public static function batchFinished($success, array $results, array $operations) {
    if ($success) {
      \Drupal::messenger()->addMessage("Batch process completed successfully.");

      if (!empty($results['processed'])) {
        \Drupal::messenger()->addMessage("Processed nodes: " . implode(', ', $results['processed']));
      }
      if (!empty($results['errors'])) {
        \Drupal::messenger()->addError("Errors encountered: " . implode(', ', $results['errors']));
      }
    }
    else {
      \Drupal::messenger()->addError("Batch process encountered an error.");
    }
  }

}