<?php
/**
 * @file
 * Contains install/update/delete functions and hooks.
 */

/**
 * Implements hook_uninstall().
 */
function svg_image_uninstall() {
  $moduleName = 'svg_image';
  $configManager = \Drupal::getContainer()->get('config.manager');
  $configFactory = $configManager->getConfigFactory();

  // We need to clear only few config values.
  $svgImageConfigs = ['svg_render_as_image', 'svg_attributes'];

  $dependentConfigs = $configManager
    ->findConfigEntityDependents('module', ['svg_image']);

  // Clear all dependent configs, set standard Image as a dependency and clear
  // SVG Image related field properties.
  foreach ($dependentConfigs as $config) {
    $name = $config->getConfigDependencyName();
    $editableConfig = $configFactory->getEditable($name);

    $configData = $editableConfig->getRawData();

    $dependencyKey = array_search($moduleName, $configData['dependencies']['module']);

    $configData['dependencies']['module'][$dependencyKey] = 'image';

    // Delete SVG Image dependent configs.
    foreach ($svgImageConfigs as $svgImageConfig) {
      if (!empty($configData['settings']) && array_key_exists($svgImageConfig, $configData['settings'])) {
        unset($configData['settings'][$svgImageConfig]);
      }
    }

    $editableConfig->setData($configData)->save(TRUE);
  }

  $allFieldsConfigs = $configFactory->listAll('field.field');

  $changedFields = [];
  foreach ($allFieldsConfigs as $fieldConfig) {
    $editableConfig = $configFactory->getEditable($fieldConfig);

    if ($editableConfig->get('field_type') === 'image') {
      $availableExtensions = explode(' ', $editableConfig->get('settings.file_extensions'));
      $svgExtensionPosition = array_search('svg', $availableExtensions, TRUE);

      if ($svgExtensionPosition !== FALSE) {
        unset($availableExtensions[$svgExtensionPosition]);
        $editableConfig->set(
          'settings.file_extensions',
          implode(' ', $availableExtensions)
        )->save();

        $changedFields[] = $editableConfig->get('field_name');
      }
    }
  }

  // Notice user about the changes that we has done.
  if (!empty($changedFields)) {
    $message = t(
      'SVG was removed from the allowed extensions list in fields: @field_list.',
      ['@field_list' => implode(', ', $changedFields)]
    );
    \Drupal::messenger()->addWarning($message);
  }
}