Support upload field type for custom field of Post Data. Note, this MU plugin required the upload

forminator-support-upload-field-type-for-custom-field.php

<?php
/**
 * Plugin Name: [Forminator Pro] - Support upload field type for custom field of Post Data
 * Description: [Forminator Pro] - Support upload field type for custom field of Post Data. Note, this MU plugin required the upload field that set before the post data field. Also, you should enable show files in media library.
 * Author: Thobk @ WPMUDEV
 * Author URI: https://premium.wpmudev.org
 * License: GPLv2 or later
 */
if ( ! defined( 'ABSPATH' ) || ( defined( 'WP_CLI' ) && WP_CLI ) ) {
	return;
}


/**
 * Screenshots:
 * https://share.getcloudapp.com/KouZqQOn
 * https://share.getcloudapp.com/7KupwDJz/
 */
add_action( 'after_setup_theme', 'wpmudev_fm_support_upload_field_type_for_custom_field_func', 100 );

function wpmudev_fm_support_upload_field_type_for_custom_field_func() {
	if ( defined('FORMINATOR_PRO') && class_exists( 'Forminator' ) ) {
		class WPMUDEV_FM_U4CF{
			private $upload_datas = [];
			private $custom_upload_fields = [];
			private $save_to_lib = 0;
			public function __construct(){
				add_filter( 'forminator_handle_specific_field_types', array( $this, 'cache_upload_file_datas' ), 10, 3 );

				if( class_exists('acf') ){
					add_action( 'forminator_post_data_field_post_saved', array( $this, 'update_upload_field_meta' ), 10, 3 );
				}
			}

			public function cache_upload_file_datas( $field_data, $form_field_obj, $field_array ){
				if( isset( $field_array['type'] ) ){
					if( $field_array['type'] === 'upload' && isset( $field_data['file']['file_url'] ) ){
						$this->upload_datas[ $field_array['element_id'] ] = $field_data['file']['file_url'];

						$this->save_to_lib = ! empty( $field_array['use_library'] );
					}elseif( $field_array['type'] === 'postdata' ){
						if( ! empty( $field_array['options'] ) ){
							foreach( $field_array['options'] as $meta ){
								if( ! empty( $meta['value'] ) && strpos( $meta['value'], '{upload-') === 0 ){
									$upload_field = trim( $meta['value'], ' {}' );
									if( isset( $this->upload_datas[ $upload_field ] ) ){
										$this->custom_upload_fields[ $meta['label'] ] = $this->upload_datas[ $upload_field ];
									}
								}
							}

							if( $this->custom_upload_fields ){
								foreach( $field_data['post-custom'] as $id => $meta ){
									if( isset( $this->custom_upload_fields[ $meta['key'] ] ) ){
										$field_data['post-custom'][ $id ]['value'] = $this->custom_upload_fields[ $meta['key'] ];
									}
								}
							}
						}
					}
				}
				return $field_data;
			}

			public function update_upload_field_meta( $post_id, $field, $data ){
				if( ! empty( $data['post-custom'] ) && $this->save_to_lib ){
					foreach( $data['post-custom'] as $custom_field ){
						if( isset( $custom_field['key'] ) && false !== strpos( $custom_field['key'], 'upload-' ) ){
							$file = get_field( $custom_field['key'], $post_id );
							if( $file ){
								$file_id = attachment_url_to_postid( $file );
								if( $file_id ){
									update_field( $custom_field['key'], $file_id, $post_id );
								}
							}
						}
					}
				}
			}
		}

		$run = new WPMUDEV_FM_U4CF;
			
	}
}