edlp_d8/sites/all/themes/custom/edlptheme/edlptheme.theme

<?php

/**
 * @file
 * Functions to support theming in the edlp theme.
 */

use Drupal\Core\Url;
use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\Template\Attribute;

// function edlptheme_preprocess_input(&$vars){
  // dsm($vars, 'vars');
  // $vars['attributes']['placeholder'] = "salut";
// }

function edlptheme_preprocess_node(&$vars){
  $node = $vars['elements']['#node'];
  $options = ['absolute' => TRUE];
  $url = Url::fromRoute('entity.node.canonical', ['node' => $node->id()], $options);
  $system_path = $url->getInternalPath();
  $vars['link_attributes'] = new Attribute(array(
    'data-drupal-link-system-path' => $system_path=='' ? '<front>' : $system_path
  ));
}

/**
 * Implements hook_form_alter
 */
function edlptheme_form_user_login_form_alter(&$form, FormStateInterface $form_state, $form_id) {
  // dpm($form_id, 'form_id');
  // dpm($form, 'form');
  $form['name']['#attributes']['placeholder'] = (string) $form['name']['#title'];
  unset($form['name']['#title']);
  $form['pass']['#attributes']['placeholder'] = (string) $form['pass']['#title'];
  unset($form['pass']['#title']);
}

function edlptheme_preprocess_edlp_productions(&$vars){
  foreach($vars['nodes'] as &$node){
    switch($node['vm']){
      case "image_2_columns":
        $cols = 4;
        break;
      case "image_1_columns":
        $cols = 2;
        break;
      case "text_1_column":
        $cols = 2;
        break;
    };
    $node['cols'] = $cols;
  }
  // dpm($vars);
}

function edlptheme_preprocess_node__enregistrement__index(&$vars){
  $node = $vars['elements']['#node'];
  $options = ['absolute' => TRUE];
  $url = Url::fromRoute('entity.node.canonical', ['node' => $node->id()], $options);
  $system_path = $url->getInternalPath();
  // get the audio file url
  $field_son_values = $node->get('field_son')->getValue();
  $son_fid = count($field_son_values) ? $field_son_values[0]['target_id'] : "";
  $son_file = \Drupal\file\Entity\File::load($son_fid);
  $son_url = null;
  if($son_file){
    $son_uri = $son_file->getFileUri();
    $son_url = file_create_url($son_uri);
  }

  $vars['link_attributes'] = new Attribute(array(
    'data-drupal-link-system-path' => $system_path=='' ? '<front>' : $system_path,
    'audio_url' => $son_url,
    'nid' => $node->id(),
    'class' => array('audio-link', 'ajax-link')
  ));
  // dpm($vars['link_attributes']);
}

function edlptheme_preprocess_node__enregistrement__player_cartel(&$vars){
  // dpm($vars);
  // if transcript not empty
  $url = Url::fromRoute('entity.node.canonical', ['node'=>$vars['node']->id()], array(
    'attributes' => array(
      'class' => ['link-transcript', 'ajax-link'],
      'viewmode'=>'transcript'
    )
  ));
  $vars['link_transcript'] = array(
    '#title' => t("Lire le text."),
    '#type' => 'link',
    '#url' => $url,
    '#options'=>array(
      'attributes' => array(
        'data-drupal-link-system-path' => $url->getInternalPath()
      )
    )
  );
  // TODO: refacorize the link generator as following :
  // $url = Url::fromRoute('entity.taxonomy_term.canonical', ['taxonomy_term'=>$tid]);
  // $url->setOptions(array(
  //   'attributes' => array(
  //     'class' => ['index-link', 'ajax-link'],
  //     'viewmode'=>'index',
  //     'tid'=>$tid,
  //     'data-drupal-link-system-path' => $url->getInternalPath()
  //   )
  // ));
  // $entree['index_link'] = Link::fromTextAndUrl('index', $url);

  // if article not empty
  $url = Url::fromRoute('entity.node.canonical', ['node'=>$vars['node']->id()], array(
    'attributes' => array(
      'class' => ['link-article', 'ajax-link'],
      'viewmode'=>'article'
    )
  ));
  $vars['link_article'] = array(
    '#title' => t("Lire l'article."),
    '#type' => 'link',
    '#url' => $url,
    '#options' => array(
      'attributes'=>array(
        'data-drupal-link-system-path' => $url->getInternalPath()
      )
    )
  );
  // if article or transcript
  $vars['col_left'] = true;

  // if
  $vars['col_right'] = true;

}