Ticket #2775: user-caps-meta.php

<?php
/*
Plugin Name:lesscaps 
Plugin URI: http://www.creighton.edu
Description: I'll fill you in on this later.  Don't worry about it, it'll be fine. 
Author: Joel vanBrandwijk 
Version: .00a
Author URI: http://www.creighton.edu
*/ 

function userEdit_cap_map($cap, $user_id, $args){
        $args=$args[0];
        if($cap == 'edit_users'){
                //if we don't have any arguments, then we're asking a situation-free question.  Assume the best
                if(count($args) === 0){
                        return Array();
                }

                //get current and target user objects for later use
                global $current_user;
                $target_user = new WP_User($args['target_id']);

                switch($args['action']){
                        case 'adduser':
                                if(compare_caps($current_user->roles, $args['target_state']) === 1){
                                        return Array();
                                }
                                break;
                        case 'promote':
                                if(compare_caps($current_user->roles, $args['target_state']) === 1){
                                        if($target_user->id === 0){
                                                return Array();
                                        } elseif (compare_caps($current_user->roles, $target_user->roles) === 1){
                                                return Array();
                                        }
                                }
                                break;
                        case 'edit':
                                if(compare_caps($current_user->roles, $target_user->roles) === 1){
                                        return Array();
                                }
                                break;
                        case 'delete':
                        case 'dodelete':
                        default:
                                if(compare_caps($current_user->roles, $target_user->roles) === 1) {
                                        return Array();
                                }
                                break;
                }
        } else {
                return false;
        }
}

function compare_caps($role1, $role2){
        //make life easy on ourselves...
        $caps1 = array();
        $caps2 = array();
        global $wp_roles;

        if(is_array($role1)){
                foreach($role1 as $r1){
                        $caps1 = array_merge($wp_roles->roles[$r1]['capabilities'], $caps1);
                }
        } else {
                $caps1 = $wp_roles->roles[$role1]['capabilities'];
        }
        if(is_array($role2)){
                foreach($role2 as $r2){
                        $caps2 = array_merge($wp_roles->roles[$r2]['capabilities'], $caps2);
                }
        } else {
                $caps2 = $wp_roles->roles[$role2]['capabilities'];
        }

        //if role1 and role2 are equal, return 0
        if(array_diff_assoc($caps1, $caps2) == array() && array_diff_assoc($caps2, $caps1) == array()){
                return 0;
        }

        //if role2 is a proper subset of role1, return 1
        if(array_diff_assoc($caps2, array_intersect_assoc($caps1, $caps2)) == array()){
                return 1;
        }

        //if role1 is a proper subset of role2, return -1
        if(array_diff_assoc($caps1, array_intersect_assoc($caps2, $caps1)) == array()){
                return -1;
        }

        //if role1 and role2 have exclusive elements, return 0
        return 0;
}

add_filter('maps_cap', 'userEdit_cap_map', 1, 3);
?>