ACF Backend Notifications on Change (WordPress) - When a user makes changes from the Back End, we create a: post notification or something else

backend-change-notifications.php

<?php

// What is interesting about this plugin is that it does a deep compare between the post and the updated post 
// and get the changes inside ACF, 
// so you will know if an admin or someone has changed an image, a field, a repeater, etc. and send a mail, a post, or whatever

// INSTALLATION:
// Create inside /plugins/ a folder named /backend-change-notifications
// Paste inside /backend-change-notifications this backend-change-notifications.php file

/**
 * The plugin bootstrap file
 *
 * @link              iproject.cat
 * @since             1.0.0
 * @package           iProject - Change Backend Notifications 
 *
 * @wordpress-plugin
 * Plugin Name:       iProject - ACF Backend Notifications on Change
 * Plugin URI:        https://iproject.cat
 * Description:       When a user makes changes from the Back End, we create a notification for users.
 * Version:           1.0.0
 * Author:            Iproject.cat
 * Author URI:        iproject.cat
 * License:           GPL-2.0+
 * License URI:       http://www.gnu.org/licenses/gpl-2.0.txt
 * Text Domain:       change-backend-notifications
 * Domain Path:       /languages
 */

// If this file is called directly, abort.
if ( ! defined( 'WPINC' ) ) {
	die;
}

define( 'Change_Backend_Notifications', '1.0.0' );

// PRE-GET DATA SAVED ON FIELDS
add_action('acf/save_post', 'my_acf_save_post', 5);
function my_acf_save_post( $post_id ) {
    
    if (substr( $post_id, 0, 5 ) !== "user_") return; // If the user is not being modified do nothing
    $prev_values = get_fields( $post_id );
    $GLOBALS['prev_values'] = $prev_values;
}

// GET END DATA SAVED ON FIELDS
add_action('acf/save_post', 'my_acf_save_post_after');
function my_acf_save_post_after( $post_id ) {

    if (substr( $post_id, 0, 5 ) !== "user_") return; // If the user is not being modified do nothing
    $end_values = get_fields( $post_id );

    // If the user is being created do not send notifications
    error_log("user initial value:");
    error_log(print_r($GLOBALS['prev_values'],TRUE));
    if (empty($GLOBALS['prev_values'])){ 
        error_log("there is nothing so is a new user");
        return;
    }

    $cambios = compare_multi_Arrays($end_values, $GLOBALS['prev_values']);
    error_log(print_r($cambios,TRUE));

    $userId = str_replace("user_", "", $post_id);
    if (empty($cambios)) return;

    $camposModificados = "";
    foreach ($cambios as $key => $cambio){
        $objeto = get_field_object($key, 'user_' . $userId );
        $camposModificados .= $objeto['label'] . "<br>";
    }
    error_log(print_r($camposModificados,TRUE));

    $cambios = print_r($cambios,TRUE);
    if (strpos($cambios, 'less') !== false) {
        $camposModificados .= "Repeater fields have been deleted";
    }
    if (strpos($cambios, 'more') !== false) {
        $camposModificados .= "Repeater fields have been added";
    }
    
    publicarNotificacionBackend($userId, $camposModificados);
}

// Stackoveflow compare array -> https://stackoverflow.com/questions/7389176/compare-multidimensional-arrays-in-php
// There are commented changes to the original function
function compare_multi_Arrays($array1, $array2){
    $result = array();
    foreach($array1 as $k => $v) {
      if(is_array($v) && isset($array2[$k]) && is_array($array2[$k])){
        $sub_result = compare_multi_Arrays($v, $array2[$k]);
        //merge results
        foreach(array_keys($sub_result) as $key){
          if(!empty($sub_result[$key])){
            $result[$key] = array_merge_recursive($result[$key],array($k => $sub_result[$key]));
          }
        }
      }else{
        if(isset($array2[$k])){
          if($v !== $array2[$k]){
              // clean response array to send data to client
            //$result["diff"][$k] = array("from"=>$v,"to"=>$array2[$k]);
            //$result[$k] = array($array2[$k]);
            $result[$k] = "";
          }
        }else{
          $result["more"][$k] = $v;
        }
      }
    }
    foreach($array2 as $k => $v) {
        if(!isset($array1[$k])){
            $result["less"][$k] = $v;
        }
    }
    return $result;
}

// This function creates a wordpress post used as notification
function publicarNotificacionBackend($userId, $mensaje){
    $user = get_user_by('id', $userId);
    $mensajeFinal = "<strong>Modified fields of your profile:</strong> \n" . $mensaje;

    // Post Notification creation
    $new_post = array(
        'post_title' => $user->user_firstname . ", has modified information in your profile",
        'post_content' => $mensajeFinal,
        'post_status' => 'publish',
        'post_type' => 'post',
    );
    $postId = wp_insert_post($new_post);

    // UPDATE ACF data within each user
    //update_field("enviar_a", "usuarios", $postId); 
    //update_field("usuarios_a_enviar", array($user->ID), $postId); // 1 es admin guillermo 2 es tmagana
}