<?php

namespace Drupal\site_users\Form;

use Drupal\Core\Form\ConfigFormBase;
use Drupal\Core\Form\FormStateInterface;
use Drupal\field\FieldConfigInterface;

/**
 * Formulário de configuração do módulo Site Users.
 */
class SiteUsersSettingsForm extends ConfigFormBase {

  /**
   * Returns all configurable user fields, discovered dynamically.
   *
   * @return array
   *   Associative array of field_name => label.
   */
  protected function getEditableFields(): array {
    $definitions = \Drupal::service('entity_field.manager')
      ->getFieldDefinitions('user', 'user');

    $fields = [];
    foreach ($definitions as $field_name => $definition) {
      if ($definition instanceof FieldConfigInterface) {
        $provider = $this->getFieldStorageProvider($field_name);
        $fields[$field_name] = $this->t('@label [@module:@field]', [
          '@label' => $definition->getLabel(),
          '@module' => $provider,
          '@field' => $field_name,
        ]);
      }
    }
    ksort($fields);
    return $fields;
  }

  /**
   * Finds which module provides the field storage config file.
   *
   * @param string $field_name
   *   The field name.
   *
   * @return string
   *   The module name, or 'unknown' if not found.
   */
  protected function getFieldStorageProvider(string $field_name): string {
    $config_file = 'field.storage.user.' . $field_name . '.yml';
    $module_handler = \Drupal::moduleHandler();
    $root = \Drupal::root();

    foreach ($module_handler->getModuleList() as $module_name => $module) {
      foreach (['config/install', 'config/optional'] as $dir) {
        if (file_exists($root . '/' . $module->getPath() . '/' . $dir . '/' . $config_file)) {
          return $module_name;
        }
      }
    }

    return 'unknown';
  }

  /**
   * {@inheritdoc}
   */
  public function getFormId() {
    return 'site_users_settings_form';
  }

  /**
   * {@inheritdoc}
   */
  protected function getEditableConfigNames() {
    return ['site_users.settings'];
  }

  /**
   * {@inheritdoc}
   */
  public function buildForm(array $form, FormStateInterface $form_state) {
    $config = $this->config('site_users.settings');

    // Fieldset para configurações de fotos.
    $form['photos'] = [
      '#type' => 'fieldset',
      '#title' => $this->t('Photo settings'),
      '#collapsible' => FALSE,
    ];

    $form['photos']['photos_max_count'] = [
      '#type' => 'number',
      '#title' => $this->t('Number of photos allowed'),
      '#description' => $this->t('Maximum number of photos a user can add to the profile.'),
      '#default_value' => $config->get('photos.max_count') ?? 5,
      '#min' => 1,
      '#max' => 100,
      '#required' => TRUE,
    ];

    $form['photos']['photos_ldap_attribute'] = [
      '#type' => 'textfield',
      '#title' => $this->t('LDAP photo attribute'),
      '#description' => $this->t('If LDAP is enabled, enter the name of the attribute that contains the user photo (e.g., thumbnailPhoto, jpegPhoto).'),
      '#default_value' => $config->get('photos.ldap_attribute') ?? 'jpegPhoto',
      '#maxlength' => 255,
    ];

    // Fieldset para campos editáveis pelo próprio usuário.
    $form['user_editable_fields'] = [
      '#type' => 'fieldset',
      '#title' => $this->t('User-editable profile fields'),
      '#description' => $this->t('Select which fields users can edit on their own profile. Fields protected by other modules remain non-editable regardless of this setting.'),
      '#tree' => TRUE,
    ];

    $definitions = \Drupal::service('entity_field.manager')
      ->getFieldDefinitions('user', 'user');
    $access_handler = \Drupal::entityTypeManager()
      ->getAccessControlHandler('user');

    foreach ($this->getEditableFields() as $field_name => $label) {
      $is_protected = $access_handler
        ->fieldAccess('edit', $definitions[$field_name], NULL, NULL, TRUE)
        ->isForbidden();

      $form['user_editable_fields'][$field_name] = [
        '#type' => 'checkbox',
        '#title' => $label,
        '#default_value' => $config->get('user_editable_fields.' . $field_name) ?? TRUE,
        '#disabled' => $is_protected,
        '#description' => $is_protected ? $this->t('Protected by another module.') : '',
      ];
    }

    return parent::buildForm($form, $form_state);
  }

  /**
   * {@inheritdoc}
   */
  public function submitForm(array &$form, FormStateInterface $form_state) {
    $config = $this->config('site_users.settings');

    $config
      ->set('photos.max_count', $form_state->getValue('photos_max_count'))
      ->set('photos.ldap_attribute', $form_state->getValue('photos_ldap_attribute'));

    $definitions = \Drupal::service('entity_field.manager')
      ->getFieldDefinitions('user', 'user');
    $access_handler = \Drupal::entityTypeManager()
      ->getAccessControlHandler('user');
    $editable = $form_state->getValue('user_editable_fields');
    foreach (array_keys($this->getEditableFields()) as $field_name) {
      $is_protected = $access_handler
        ->fieldAccess('edit', $definitions[$field_name], NULL, NULL, TRUE)
        ->isForbidden();
      if ($is_protected) {
        // Campos protegidos por outros módulos são sempre não-editáveis.
        $config->set('user_editable_fields.' . $field_name, FALSE);
      }
      elseif (isset($editable[$field_name])) {
        $config->set('user_editable_fields.' . $field_name, (bool) $editable[$field_name]);
      }
    }

    $config->save();

    parent::submitForm($form, $form_state);
  }

}