[Forminator Pro] - Submission unique identifier

wpmudev-forminator-unique-identifier.php

<?php
/**
* Plugin Name: [Forminator Pro] - Submission unique identifier
* Plugin URI: https://premium.wpmudev.org/
* Description: Generate a unique code for each form submission (as of 1.12.1)
* Author: Alessandro Kaounas @ WPMUDEV
* Author URI: https://premium.wpmudev.org/
* Task: 0/11289012348292/1175564087636585
* License: GPLv2 or later
*/

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

// No need to do anything if the request is via WP-CLI.
if ( defined( 'WP_CLI' ) && WP_CLI ) {
	return;
}

if ( ! class_exists( 'WPMUDEV_Forminator_Unique_Identifier' ) ) {
    
    class WPMUDEV_Forminator_Unique_Identifier {

        // User defined settings
        private $forms = array(
            100 => 'hidden-1',
            200 => 'hidden-2',
            // ... more (form_id) - (hidden_field) pairs here
        );

        /** 
	  * Unique identifier length (Default: 6)
	  * Keep length at least 4 to avoid any infinite loops
	  */ 
        private $length = 6;

        private $generations = 0;
        private static $_instance = null;

        public static function get_instance() {

            if( is_null( self::$_instance ) ){
                self::$_instance = new WPMUDEV_Forminator_Unique_Identifier();
            }

            return self::$_instance;
            
        }

        private function __construct() {
            
            $this->init();

        }

        public function init(){

            // Do some checks here
            if ( ! defined( 'FORMINATOR_VERSION' ) || FORMINATOR_VERSION < '1.12' || ! class_exists( 'Forminator_API' ) ) {
                return;
            }

            // Generate a unique identifier
            add_filter( 'forminator_custom_form_submit_field_data', array( $this, 'wpmudev_randomize_hidden_input' ), 10, 2 );
            
            // Ajax method (action)
            add_action( 'forminator_form_after_save_entry', array( $this, 'wpmudev_forminator_custom_form_after_save_entry' ), 10, 2 );

            // Post method (filter)
            add_filter( 'forminator_form_submit_response', array( $this, 'wpmudev_forminator_custom_form_after_save_entry' ), 10, 2 );

            // Ajax method (filter)
            add_filter( 'forminator_form_ajax_submit_response', array( $this, 'wpmudev_forminator_custom_form_after_save_entry' ), 10, 2 );

        }

        public function wpmudev_forminator_custom_form_after_save_entry( $form_id, $response ){

            if( ! wp_doing_ajax() ){
                // Swap variables when POST method
                list( $form_id, $response ) = array( $response, $form_id );
            }

            if( ! in_array( $form_id, array_keys( $this->forms ) ) ){
                return;
            }
            
            $entries = Forminator_API::get_entries( $form_id );

            if( is_array( $entries ) ){
                $entry = current( $entries );
                if( $entry instanceof Forminator_Form_Entry_Model ){
                    $code = $entry->get_meta( $this->forms[$form_id] );
                }
            }

            if( ! isset( $code ) ){
                return;
            }

            $form = Forminator_API::get_form( $form_id );

            if( ! $form instanceof Forminator_Form_Model ) {
                return;
            }
        
            $msg = sprintf( __( "Form submitted with unique code: <strong>%s</strong>", 'wpmudev' ), $code );

            if( wp_doing_ajax() ){
                $form->settings['thankyou-message'] .= "<br>" . $msg;
                wp_send_json_success( 
                    array(
                        'success' => true,
                        'message' => $form->settings['thankyou-message'],
                        'behav'   => $form->settings['submission-behaviour']
                    )
                );
            }else{
                $response['message'] .= "<br>" . $msg;
            }

            return $response;

        }

        public function wpmudev_randomize_hidden_input( $field_data_array, $form_id ) {

            if( ! in_array( $form_id, array_keys( $this->forms ) ) ){
                return $field_data_array;
            }

            foreach( $field_data_array as $key => $field ){
                if( $field['name'] === $this->forms[$form_id] ){
                    unset( $field_data_array[$key] );
                }
            }

            $field_data_array[] = array(
                'name'     => $this->forms[$form_id],
                'value'    => $this->wpmudev_randomizer( $form_id, $this->forms[$form_id] )
            );

            return $field_data_array;

        }

        public function wpmudev_is_unique( $num = '', $form_id, $form_field ) {

            global $wpdb;

            $query = "SELECT COUNT(*) FROM {$wpdb->prefix}frmt_form_entry_meta
            WHERE meta_key LIKE '{$form_field}' 
            AND   meta_value LIKE '{$num}'
            AND   entry_id IN( SELECT entry_id 
            FROM  {$wpdb->prefix}frmt_form_entry WHERE form_id = {$form_id} );";
            
            if( 0 === (int) $wpdb->get_var( $query ) ){
                return true;
            }else{
                $this->generations++;
                return false;
            }

        }
        
        public function wpmudev_randomizer( $form_id = 0, $form_field = 'hidden-1' ) {
            
            $num = '';
        
            $characters = '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';

            for ($i = 0; $i < $this->length; $i++) {	
                $num .= $characters[rand(0, strlen( $characters ) - 1)]; 
            }
            
            if( $this->generations > pow( strlen( $characters ), $this->length ) ){
                return __( 'No unique codes available to assign.', 'wpmudev' );
            }

            if( (int) $num === 0 ){
                return $this->wpmudev_randomizer( $form_id, $form_field );
            }
            
            if( $this->wpmudev_is_unique( $num, $form_id, $form_field ) ) {
                return $num;
            } else {
                return $this->wpmudev_randomizer( $form_id, $form_field );
            }
        }

    }

    add_action( 'plugins_loaded', function(){
        return WPMUDEV_Forminator_Unique_Identifier::get_instance();
    });

}