Wordpress Plugin that adds ability to conditionally show/hide a block of text in an ApproveMe (WP E-Signature) contract from a shortcode enclosure

e-signature-show-if.php

<?php
/*
Plugin Name: E-Signature (ApproveMe) Show-If Gravity Forms Shortcode Block
Description: Description: Adds ability to conditionally show/hide a block of text in an ApproveMe (WP E-Signature) contract from a shortcode enclosure [esiggravity_show_if value='foo' formid='1' field_id='1'] Some HTML content [/esiggravity_show_if]
Version: 1.0.0
Author: Arthur Goldsmith
*/


if ( file_exists( ABSPATH . '/wp-content/plugins/gravity-signature-forms-add-on/includes/esig-gf-generate-value.php' ) ) {
    // Include the other plugin file
    require_once( ABSPATH . '/wp-content/plugins/gravity-signature-forms-add-on/includes/esig-gf-generate-value.php' );

    /**
     *
     * @package ESIG_GRAVITY_ShowIf
     * @author  Arthur Goldsmith
     */
    if (!class_exists('ESIG_GRAVITY_ShowIf')) :

        class ESIG_GRAVITY_ShowIf extends ESIG_GF_VALUE {
            protected static $instance = null;

            private function __construct() {
                add_shortcode('esiggravity_show_if', array($this, 'render_esiggravity_show_if'));
            }

            public static function get_instance() {

                // If the single instance hasn't been set, set it now.
                if (null == self::$instance) {
                    self::$instance = new self;
                }

                return self::$instance;
            }

            // Define the shortcode handler function
            public function render_esiggravity_show_if($atts, $content = '') {
                extract(shortcode_atts(array(
                    'formid' => '',
                    'field_id' => '',
                    'value' => null,
                    'option' => 'default',
                                ), $atts, 'esiggravity'));

                if (!function_exists('WP_E_Sig'))
                    return;

                // creating esignature api 
                $api = new WP_E_Api();

                $csum = ESIG_GET('csum');

                if (empty($csum)) {
                    $document_id = get_option('esig_global_document_id');
                } else {
                    $document_id = $api->document->document_id_by_csum($csum);
                }
            
                // getting document meta for gravity form 

                $entry_id = ESIG_GF_SETTINGS::entryId($document_id); //$api->meta->get($document_id, 'esig_gravity_entry_id');
            
                if (empty($entry_id)) {
                    return do_shortcode($content);
                }
                
                $field_value = self::generate_value(filter_var($formid, FILTER_SANITIZE_NUMBER_INT), filter_var($field_id, FILTER_SANITIZE_NUMBER_INT), $entry_id, $document_id, 'value', $option);
                
                if(!is_null($value)) {
                    if($value == $field_value) {
                        return do_shortcode($content);
                    } else {
                        return '';
                    }
                }
            }

        }
    endif;

    add_action( 'plugins_loaded', array( 'ESIG_GRAVITY_ShowIf', 'get_instance' ) );
}