<?php

namespace Drupal\cohesion_javascript_element\Plugin\CustomElement;

use Drupal\cohesion_elements\CustomElementPluginBase;

/**
 * Cohesion Javascript.
 *
 * The purpose of this module is to allow component developers to leverage Drupal's
 * library system. It allows them to specify libraries defined in the *.libraries.yml
 * file if the component rely's on a certain library to run any custom code.
 *
 * @package Drupal\cohesion\Plugin\CustomElement
 *
 * @CustomElement(
 *   id = "cohesion_javascript_element",
 *   label = @Translation("Custom Javascript")
 * )
 */
class CohesionJavascriptElementForm extends CustomElementPluginBase
{

  /**
   * {@inheritdoc}
   */
  public function getFields() {

    // Get current fields from parent class we extend
    // so we can add to them.
    $fields = parent::getFields();

    $fields['id'] = [
      'htmlClass' => 'col-xs-6',
      'type' => 'textfield',
      'title' => 'ID (used for drupalSettings)',
    ];

    $fields['scope'] = [
      'htmlClass' => 'col-xs-6',
      'type' => 'select',
      'title' => 'Scope (Footer recommended)',
      'nullOption' => 'footer',
      'defaultValue' => 'footer',
      'options' => [
        'header' => 'Header',
        'footer' => 'Footer',
      ]
    ];

    $fields['javascript'] = [
      'htmlClass' => 'col-xs-12',
      'type' => 'textarea',
      'title' => 'Add Custom Javascript',
    ];

    $fields['add_jquery'] = [
      'htmlClass' => 'col-xs-2',
      'type' => 'checkbox',
      'title' => 'Add jQuery',
      // These fields are specific to this form field type.
      'defaultValue' => true,
    ];

    $fields['libraries'] = [
      'htmlClass' => 'col-xs-10',
      'type' => 'textarea',
      'title' => 'Dependency Libraries (one per line)',
    ];

    $fields['drupalSettings'] = [
      'htmlClass' => 'col-xs-12',
      'type' => 'textarea',
      'title' => 'drupalSettings (should be valid JSON)',
    ];

    return $fields;
  }

  /**
   * {@inheritdoc}
   */
  public function render($element_settings, $element_markup, $element_class, $element_context = []) {

    $cache = &drupal_static('cohesion_javascript_element', []);

    // Create form id to pass to twig template and front end settings.
    $formId = !empty($element_settings['id']) ? $element_settings['id'] : $element_class;

    // Create initial render array.
    $renderArr = [
      '#theme' => 'cohesion_javascript_element'
    ];

    // Set some defaults for Attach Inline module.
    $js = [
      'data' => '',
      'scope' => 'footer',
      'dependencies' => []
    ];

    // Add any attributes to <script> tag
    if(isset($element_markup['attributes'])) {
      foreach($element_markup['attributes'] as $item) {
        $js['attributes'][$item['attribute']] = $item['value'];
      }
    }

    if(!empty($element_settings['javascript'])) {
      $js['data'] = $element_settings['javascript'] ?: '';
      $js['scope'] = $element_settings['scope'] ?: 'footer';
    }

    // Attach the libraries to the render array.
    if (!empty($element_settings['libraries'])) {
      // Taken from https://stackoverflow.com/questions/17918381/how-to-explode-a-string-with-spaces-and-new-lines
      $libraries = preg_split('/[\s]+/', $element_settings['libraries']);

      $libraries = array_filter($libraries, function($library){
        return $library != '1';
      });

      $js['dependencies'] = $libraries ?: [];
    }

    // Add jQuery as a dependency
    if(!empty($element_settings['add_jquery'])) {
      $js['dependencies'][] = 'core/jquery';
    }

    // Attach drupalSettings to the front end.
    if (!empty($element_settings['drupalSettings'])) {
      $drupalSettings = json_decode($element_settings['drupalSettings']);
      $js['dependencies'][] = 'core/drupalSettings';
      $renderArr['#attached']['drupalSettings'][$formId] = $drupalSettings;
    }

    $renderArr['#attached']['js'][] = $js;

    // Prevent duplicate code from rendering on the page.
    $encodedRenderArr = base64_encode(json_encode($renderArr));
    if(in_array($encodedRenderArr, $cache)) {
      return;
    } else {
      $cache[] = $encodedRenderArr;
      drupal_static('cohesion_javascript_element', $cache);
    }

    // Render the element.
    return $renderArr;
  }
}