<?php

/*
 * Copyright (C) 2015 Julien Fastré <julien.fastre@champs-libres.coop>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

namespace Chill\MainBundle\Security;

/**
 * 
 *
 * @author Julien Fastré <julien.fastre@champs-libres.coop>
 */
class RoleProvider
{
    /**
     *
     * @var ProvideRoleInterface[]
     */
    private $providers = array();
    
    /**
     * an array where keys are the role, and value is the title
     * for the given role.
     * 
     * Null when not initialized.
     *
     * @var array|null
     */
    private $rolesTitlesCache = null;
    
    /**
     * Add a role provider
     * 
     * @internal This function is called by the dependency injector: it inject provider
     * @param \Chill\MainBundle\Security\ProvideRoleInterface $provider
     */
    public function addProvider(ProvideRoleInterface $provider) 
    {
        $this->providers[] = $provider;
    }
    
    /**
     * 
     * @return string[] the roles as string
     */
    public function getRoles()
    {
        $roles = array();
        foreach ($this->providers as $provider) {
            if ($provider->getRoles() !== NULL) {
                $roles = array_merge($roles, $provider->getRoles());
            }
        }
        
        return $roles;
    }
    
    /**
     * 
     * @return string[] the roles as string
     */
    public function getRolesWithoutScopes()
    {
        $roles = array();
        foreach ($this->providers as $provider) {
            if ($provider->getRolesWithoutScope() !== NULL) {
                $roles = array_merge($roles, $provider->getRolesWithoutScope());
            }
        }
        
        return $roles;
    }
    
    /**
     * initialize the array for caching role and titles
     * 
     */
    private function initializeRolesTitlesCache()
    {
        // break if already initialized
        if ($this->rolesTitlesCache !== null) {
            return;
        }
        
        foreach ($this->providers as $provider) {
            if ($provider instanceof ProvideRoleHierarchyInterface) {
                foreach ($provider->getRolesWithHierarchy() as $title => $roles) {
                    foreach($roles as $role) {
                        $this->rolesTitlesCache[$role] = $title;
                    }
                }
            } else {
                if ($provider->getRoles() !== null) {
                    $this->rolesTitlesCache = \array_merge(
                        $this->rolesTitlesCache, 
                        \array_fill_keys($provider->getRoles(), null)
                        );
                }
            }
        }
    }
    
    /**
     * Get the title for each role.
     * 
     * @param string $role
     * @return string the title of the role
     */
    public function getRoleTitle($role)
    {
        $this->initializeRolesTitlesCache();
        
        if (! \array_key_exists($role, $this->rolesTitlesCache)) {
            // this case might happens when the role is not described in 
            // `getRolesWithHierarchy`
            return null;
        }
        
        return $this->rolesTitlesCache[$role];
    }
    
}