<?php

/**
 * Chill is a software for social workers
 *
 * For the full copyright and license information, please view
 * the LICENSE file that was distributed with this source code.
 */

declare(strict_types=1);

namespace Chill\MainBundle\Security;

use function array_fill_keys;
use function array_key_exists;

class RoleProvider
{
    /**
     * @var ProvideRoleInterface[]
     */
    private $providers = [];

    /**
     * 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;

    /**
     * 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;
    }

    public function getRoles(): array
    {
        $roles = [];

        foreach ($this->providers as $provider) {
            if ($provider->getRoles() !== null) {
                $roles = array_merge($roles, $provider->getRoles());
            }
        }

        return $roles;
    }

    public function getRolesWithoutScopes(): array
    {
        $roles = [];

        foreach ($this->providers as $provider) {
            if ($provider->getRolesWithoutScope() !== null) {
                $roles = array_merge($roles, $provider->getRolesWithoutScope());
            }
        }

        return $roles;
    }

    /**
     * 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];
    }

    /**
     * initialize the array for caching role and titles.
     */
    private function initializeRolesTitlesCache()
    {
        // break if already initialized
        if (null !== $this->rolesTitlesCache) {
            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)
                    );
                }
            }
        }
    }
}