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<?php
/**
 * @file
 * Module for the Custom code of Ldap User Lookup.
 */

use DrupalCoreFormFormStateInterface;
use Drupalei_coreCommonCoreUserTrait;
use Drupalei_ssoCommonSSOLdapTrait;
use DrupalCoreAjaxAjaxResponse;
use DrupalCoreAjaxReplaceCommand;

/**
 * Implements hook_form_alter().
 */

function ei_ldap_lookup_user_form_alter(&$form, FormStateInterface &$form_state, $form_id){
  switch($form_id){
    // Adding 'Lookup' button beside signum field for specific content types.
    case 'node_contributor_form':
      $form['title']['#prefix'] = '<div id="field_title_wrapper">';
      $form['title']['#suffix'] = '</div>';

      $form['field_signum']['lookup'] = [
        '#type' => 'button',
        '#name' => 'lookup',
        '#value' => t('Lookup'),
        '#submit' => ['ei_ldap_lookup____user_field_submit'],
        '#ajax' => [
          'callback' => 'ei_ldap_lookup____user_field_callback',
          'effect' => 'fade',
        ],
        '#attributes' => ['class' => ['btn', 'btn-primary']],
      ];

      break;
  }
}

/**
 * Ajax submit to add update name and email fiels.
 */
function ei_ldap_lookup____user_field_submit(array &$form, FormStateInterface &$form_state) {
  $response = new AjaxResponse();   
  $form['title']['#value'] = "Jon Doe";
  $response->addCommand(new ReplaceCommand('#field_title_wrapper', $form['title']));
  return $response;
}

/**
 * Ajax callback to render name and email field.
 */
function ei_ldap_lookup____field_populate_callback(array &$form, FormStateInterface &$form_state) {
  return $form['title'];
}

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