<?php

/**
 * @file
 * The Crop API Drupal module.
 *
 * Provides storage and API for image crops.
 */

use Drupal\Component\Utility\UrlHelper;
use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\StreamWrapper\PublicStream;
use Drupal\crop\Entity\Crop;
use Drupal\image\Entity\ImageStyle;
use Drupal\media\MediaSourceInterface;
use Drupal\media\MediaTypeInterface;
use Drupal\file\FileInterface;

/**
 * Implements hook_theme().
 */
function crop_theme() {
  return [
    'crop_crop_summary' => [
      'variables' => ['data' => [], 'effect' => []],
    ],
  ];
}

/**
 * Prepares variables for crop_crop summary template.
 *
 * Default template: crop-crop-summary.twig.html.
 */
function template_preprocess_crop_crop_summary(&$variables) {
  if (!empty($variables['data']['crop_type'])) {
    $type = \Drupal::entityTypeManager()->getStorage('crop_type')->load($variables['data']['crop_type']);
    $variables['data']['crop_type'] = $type->label();
  }
}

/**
 * Implements hook_form_FORM_ID_alter().
 *
 * Adds crop configuration fields to media form.
 */
function crop_form_media_type_edit_form_alter(array &$form, FormStateInterface $form_state, $form_id) {
  /** @var \Drupal\media\Entity\MediaType $entity_type */
  $entity_type = $form_state->getFormObject()->getEntity();
  $options = [];
  $allowed_field_types = ['file', 'image'];

  /** @var \Drupal\Core\Field\FieldDefinitionInterface[] $fields */
  $fields = \Drupal::service('entity_field.manager')->getFieldDefinitions('media', $entity_type->id());
  foreach ($fields as $field_name => $field) {
    if (in_array($field->getType(), $allowed_field_types) && !$field->getFieldStorageDefinition()->isBaseField()) {
      $options[$field_name] = $field->getLabel();
    }
  }

  $form['#entity_builders'][] = 'crop_media_type_form_builder';
  $form['crop'] = [
    '#type' => 'fieldset',
    '#title' => t('Crop configuration'),
    '#group' => 'source_dependent',
  ];

  if (empty($options)) {
    $form['crop']['image_field'] = [
      '#type' => 'value',
      '#value' => NULL,
    ];

    $form['crop']['message'] = [
      '#markup' => t('There are no file or image fields on this bundle at the moment. In order to configure crop add at least one such field and come back.'),
    ];

    return;
  }

  $form['crop']['image_field'] = [
    '#type' => 'select',
    '#title' => t('Image field'),
    '#default_value' => $entity_type->getThirdPartySetting('crop', 'image_field'),
    '#options' => $options,
    '#empty_option' => t('- Skip field -'),
    '#empty_value' => MediaSourceInterface::METADATA_FIELD_EMPTY,
    '#description' => t('Select field that stores image which needs to be cropped.'),
  ];
}

/**
 * Entity builder for Media type.
 *
 * Adds third party settings to Media type config entity.
 *
 * @see crop_form_media_type_edit_form_alter()
 */
function crop_media_type_form_builder($entity_type, MediaTypeInterface $bundle, array &$form, FormStateInterface $form_state) {
  $bundle->setThirdPartySetting('crop', 'image_field', $form_state->getValue('image_field'));
}

/**
 * Implements hook_ENTITY_TYPE_delete().
 *
 * Deletes orphaned crops when a file is deleted.
 */
function crop_file_delete(FileInterface $file) {
  // Get all crops for the file being deleted.
  $crops = \Drupal::entityTypeManager()
    ->getStorage('crop')
    ->loadByProperties(['uri' => $file->getFileUri()]);

  foreach ($crops as $crop) {
    $crop->delete();
  }
}

/**
 * Implements hook_file_url_alter().
 */
function crop_file_url_alter(&$uri) {
  // Process only files that are stored in "styles" directory.
  if (strpos($uri, '/styles/') !== FALSE && preg_match('/\/styles\/(.*?)\/(.*?)\/(.+)/', $uri, $match)) {
    // Match image style, schema, file subdirectory and file name.
    // Get the image style ID.
    $image_style = $match[1];
    // Get the file path without query parameter.
    $parsed_uri = UrlHelper::parse($match[3]);
    // Get the file URI using parsed schema and file path.
    $file_uri = $match[2] . '://' . $parsed_uri['path'];

    // Prevent double hashing, if there is a hash argument already, do not add
    // it again.
    if (!empty($parsed_uri['query']['h'])) {
      return;
    }

    /** @var \Drupal\image\Entity\ImageStyle $image_style */
    if (!$image_style = ImageStyle::load($image_style)) {
      return;
    }

    if ($crop = Crop::getCropFromImageStyle($file_uri, $image_style)) {
      // Found a crop for this image, append a hash of it to the URL,
      // so that browsers reload the image and CDNs and proxies can be bypassed.
      $shortened_hash = substr(md5(implode($crop->position()) . implode($crop->anchor())), 0, 8);

      // If the URI has a schema and that is not http, https or data, convert
      // the URI to the external URL. Otherwise the appended query argument
      // will be encoded.
      // @see file_create_url()
      $scheme = \Drupal::service('file_system')->uriScheme($uri);
      if ($scheme && !in_array($scheme, ['http', 'https', 'data'])) {
        if ($wrapper = \Drupal::service('stream_wrapper_manager')->getViaUri($uri)) {
          $uri = $wrapper->getExternalUrl();
        }
      }

      // Append either with a ? or a & if there are existing query arguments.
      if (strpos($uri, '?') === FALSE) {
        $uri .= '?h=' . $shortened_hash;
      }
      else {
        $uri .= '&h=' . $shortened_hash;
      }
    }
  }
}