elasticsearch_search_api-1.0.x-dev/modules/esa_pager/esa_pager.module

<?php

/**
 * @file
 * Contains esa_pager.module.
 */

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

/**
 * Implements hook_theme().
 */
function esa_pager_theme() {
  return [
    'esa_pager' => [
      'template' => 'esa_pager',
      'variables' => [
        'tags' => [],
        'element' => 0,
        'parameters' => [],
        'total_items' => 0,
        'items_per_page' => 0,
        'route_name' => '',
        'route_params' => [],
      ],
    ],
  ];
}

/**
 * Prepares variables for esa pager templates.
 *
 * Based on views mini pager and pager.inc.
 *
 * @param array $variables
 *   An associative array containing:
 *   - tags: Provides link text for the next/previous links.
 *   - element: The pager's id.
 *   - parameters: Any extra GET parameters that should be retained, such as
 *     exposed input.
 */
function esa_pager_preprocess_esa_pager(array &$variables) {
  global $pager_page_array, $pager_total;

  /** @var \Drupal\Core\Pager\PagerManagerInterface $pager_manager */
  $pager_manager = \Drupal::service('pager.manager');

  if (empty($pager_page_array)) {
    $page = \Drupal::request()->request->getInt('page', 0);
    $pager_page_array = [$variables['element'] => $page];
  }

  $total_items = $variables['total_items'];
  $items_per_page = $variables['items_per_page'];
  $total_pages = ceil($total_items / $items_per_page);

  if (empty($pager_total)) {
    $pager_total = [$variables['element'] => $total_pages];
  }

  $tags = &$variables['tags'];
  $element = $variables['element'];
  $parameters = $variables['parameters'];
  $route_name = $variables['route_name'];
  $route_params = $variables['route_params'] ?? [];
  $pager = $pager_manager->getPager($element);

  // Nothing to do if there is no pager.
  if (!isset($pager)) {
    return;
  }

  $current = $pager->getCurrentPage();
  $total = $pager->getTotalPages();

  // Current is the page we are currently paged to.
  $variables['items']['current'] = $current + 1;

  if ($total > 1 && $current > 0) {
    $options = [
      'query' => $pager_manager->getUpdatedParameters($parameters, $element, $current - 1),
    ];
    $variables['items']['previous']['href'] = Url::fromRoute('<current>', [], $options)->toString();
    if (isset($tags[1])) {
      $variables['items']['previous']['text'] = $tags[1];
    }
    $variables['items']['previous']['attributes'] = new Attribute();

    $variables['items']['previous']['attributes'] = ['data-page' => $current - 1];
  }

  if ($current < ($total - 1)) {
    $options = [
      'query' => $pager_manager->getUpdatedParameters($parameters, $element, $current + 1),
    ];
    $variables['items']['next']['href'] = Url::fromRoute('<current>', [], $options)->toString();
    if (isset($tags[3])) {
      $variables['items']['next']['text'] = $tags[3];
    }
    $variables['items']['next']['attributes'] = new Attribute();
    $variables['items']['next']['attributes'] = ['data-page' => $current + 1];
  }

  // Calculate various markers within this pager piece:
  // Current is the page we are currently paged to.
  $pager_current = $current + 1;
  // First is the first page listed by this pager piece (re quantity).
  $pager_first = 1;
  // Last is the last page listed by this pager piece (re quantity).
  $pager_last = $total_pages;
  // Max is the maximum page number.
  $pager_max = $pager_total[$element];

  $i = $pager_first;
  if ($pager_last > $pager_max) {
    // Adjust "center" if at end of query.
    $i = $i + ($pager_max - $pager_last);
    $pager_last = $pager_max;
  }
  if ($i <= 0) {
    // Adjust "center" if at start of query.
    $pager_last = $pager_last + (1 - $i);
    $i = 1;
  }

  $items['pages'] = [];

  if ($i != $pager_max) {
    // Add an ellipsis if there are further previous pages.
    if ($i > 1) {
      $variables['ellipses']['previous'] = TRUE;
    }
    // Now generate the actual pager piece.
    $ellipsis_first_added = FALSE;
    $ellipsis_second_added = FALSE;
    if ($pager_current < 3) {
      $ellipsis_first_added = TRUE;
    }
    if ($pager_current > $pager_max - 3) {
      $ellipsis_second_added = TRUE;
    }

    $current_plus = ($pager_current == $pager_first) ? $pager_current + 2 : $pager_current + 1;
    $current_minus = ($pager_current == $pager_last) ? $pager_current - 2 : $pager_current - 1;

    for (; $i <= $pager_last && $i <= $pager_max; $i++) {

      if ($i == $pager_current) {
        $variables['current'] = $i;
      }

      if ($i == $pager_first || $i == $pager_last || ($i >= $current_minus && $i <= $current_plus)) {
        $options = [
          'query' => $pager_manager->getUpdatedParameters($parameters, $element, $i - 1),
        ];
        $items['pages'][$i]['href'] = Url::fromRoute($route_name, $route_params, $options)->toString();
        $items['pages'][$i]['attributes'] = ['data-page' => $i - 1];
      }
      else {
        if (!$ellipsis_first_added && $i < $pager_current) {
          $ellipsis_first_added = TRUE;
          $items['pages'][$i] = 'ellipsis';
        }

        if (!$ellipsis_second_added && $i > $pager_current) {
          $ellipsis_second_added = TRUE;
          $items['pages'][$i] = 'ellipsis';
        }
      }
    }
    // Add an ellipsis if there are further next pages.
    if ($i < $pager_max + 1) {
      $variables['ellipses']['next'] = TRUE;
    }
  }

  $variables['items']['pages'] = $items['pages'];

  // This is based on the entire current query string. We need to ensure
  // cacheability is affected accordingly.
  $variables['#cache']['contexts'][] = 'url.query_args';
  $variables['#attached']['library'] = ['esa_pager/pager'];
}