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use \Drupal\block_content\BlockContentInterface;
use Drupal\taxonomy\Entity\Term;

/**
 * Implements hook_theme_suggestions_HOOK_alter() for form templates.
 * @param array $suggestions
 * @param array $variables
 */
function proclass_theme_suggestions_block_alter(array &$suggestions, array $variables) {
  // Block suggestions for custom block bundles.
  if (isset($variables['elements']['content']['#block_content']) && $variables['elements']['content']['#block_content'] instanceof BlockContentInterface) {
    array_splice($suggestions, 1, 0, 'block__bundle__' . $variables['elements']['content']['#block_content']->bundle());
  }
}
// - Reg date in future - Coming Soon 

// - Reg date passed seats avail greater zero - Enroll Now

// - Reg date passed no seats avail - Join Waitlist

function proclass_theme_preprocess_page(array &$variables) {
  $node = \Drupal::routeMatch()->getParameter('node');
  if ($node instanceof \Drupal\node\NodeInterface) {
    if ($node->bundle() === 'proclass_programs') {
      $variables['class_status'] = _class_status($node);
    }
  }
}

function proclass_theme_preprocess_node(array &$variables) {
  $node = $variables['node'];
  if ($node->bundle() === 'proclass_programs') {
    $variables['class_status'] = _class_status($node);
  }
}

function _class_status($node) {
  if ($node->hasField('field_proclass_registrationopend') && !$node->get('field_proclass_registrationopend')->isEmpty()) {
    $registration_date = $node->get('field_proclass_registrationopend')->first()->getValue()['value'];
    $registration_date = new DateTime($registration_date);
    $current_date = new DateTime();
  }
  if ($node->hasField('field_proclass_numberofseats') && !$node->get('field_proclass_numberofseats')->isEmpty()) {
    $seats = $node->get('field_proclass_numberofseats')->first()->getValue();
  }
  if ($node->hasField('field_proclass_numberregistered') && !$node->get('field_proclass_numberregistered')->isEmpty()) {
    $registered = $node->get('field_proclass_numberregistered')->first()->getValue();
  }
  $seats_left = $seats['value'] - $registered['value'];

  $status = 'View Details';  
  // - Reg date in future - Coming Soon 
  if ($current_date < $registration_date) {
    $status = 'Coming Soon';      
  // - Reg date passed no seats avail - Join Waitlist
  } elseif ($seats_left < 1 && ($current_date >= $registration_date)) {
    $status = 'Join Waitlist';
  // - Reg date passed seats avail greater zero - Enroll Now
  } elseif ($seats_left >= 1 && ($current_date >= $registration_date)) {
    $status = 'Enroll Now';      
  }
  return $status;
}