<?php

/*
 * Copyright (C) 2016 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\PersonBundle\Widget;

use Chill\MainBundle\Templating\Widget\WidgetInterface;
use Doctrine\ORM\EntityRepository;
use Doctrine\ORM\Query\Expr;
use Doctrine\DBAL\Types\Type;
use Chill\MainBundle\Security\Authorization\AuthorizationHelper;
use Symfony\Component\Security\Core\User\UserInterface;
use Symfony\Component\Security\Core\Authentication\Token\Storage\TokenStorage;
use Chill\PersonBundle\Security\Authorization\PersonVoter;
use Symfony\Component\Security\Core\Role\Role;
use Doctrine\ORM\EntityManager;
use Chill\CustomFieldsBundle\Entity\CustomField;
use Twig\Environment;

/**
 * add a widget with person list. 
 * 
 * The configuration is defined by `PersonListWidgetFactory`
 * 
 * If the options 'custom_fields' is used, the custom fields entity will be 
 * queried from the db and transmitted to the view under the `customFields` variable.
 */
class PersonListWidget implements WidgetInterface
{
    /**
     * Repository for persons
     *
     * @var EntityRepository
     */
    protected $personRepository;
    
    /**
     * The entity manager
     *
     * @var EntityManager
     */
    protected $entityManager;
    
    /**
     * the authorization helper
     * 
     * @var AuthorizationHelper;
     */
    protected $authorizationHelper;
    
    /**
     *
     * @var TokenStorage
     */
    protected $tokenStorage;
    
    /**
     *
     * @var UserInterface
     */
    protected $user;
    
    public function __construct(
            EntityRepository $personRepostory,
            EntityManager $em,
            AuthorizationHelper $authorizationHelper,
            TokenStorage $tokenStorage
            ) {
        $this->personRepository = $personRepostory;
        $this->authorizationHelper = $authorizationHelper;
        $this->tokenStorage = $tokenStorage;
        $this->entityManager = $em;
    }

    /**
     * 
     * @param type $place
     * @param array $context
     * @param array $config
     * @return string
     */
    public function render(Environment $env, $place, array $context, array $config)
    { 
        $numberOfItems = $config['number_of_items'] ?? 20;
        
        $qb = $this->personRepository
                ->createQueryBuilder('person');
        
        // show only the person from the authorized centers
        $and = $qb->expr()->andX();
        $centers = $this->authorizationHelper
                ->getReachableCenters($this->getUser(), new Role(PersonVoter::SEE));
        $and->add($qb->expr()->in('person.center', ':centers'));
        $qb->setParameter('centers', $centers);
        

        // add the "only active" query
        if (\array_key_exists('only_active', $config) && $config['only_active'] === true) {
            $qb->join('person.accompanyingPeriods', 'ap');
            $or = new Expr\Orx();
            // add the case where closingDate IS NULL
            $andWhenClosingDateIsNull = new Expr\Andx();
            $andWhenClosingDateIsNull->add((new Expr())->isNull('ap.closingDate'));
            $andWhenClosingDateIsNull->add((new Expr())->gte(':now', 'ap.openingDate'));
            $or->add($andWhenClosingDateIsNull);
            // add the case when closingDate is in the future
            $or->add(
                    (new Expr())->between(':now', 'ap.openingDate', 'ap.closingDate')
                );
            $and->add($or);
            $qb->setParameter('now', new \DateTime(), Type::DATE);
        }

        
        if (\array_key_exists('filtering_class', $config) && $config['filtering_class'] !== NULL) {
            $filteringClass = new $config['filtering_class'];
            if ( ! $filteringClass instanceof PersonListWidget\PersonFilteringInterface) {
                throw new \UnexpectedValueException(sprintf("the class %s does not "
                        . "implements %s", $config['filtering_class'], 
                        PersonListWidget\PersonFilteringInterface::class));
            }
            $ids = $filteringClass->getPersonIds($this->entityManager, 
                    $this->getUser());
            $in = (new Expr())->in('person.id', ':ids');
            $and->add($in);
            $qb->setParameter('ids', $ids);
        }
        
        // adding the where clause to the query
        $qb->where($and);
        
        // ordering the query by lastname, firstname
        $qb->addOrderBy('person.lastName', 'ASC')
                ->addOrderBy('person.firstName', 'ASC');
        
        
        $qb->setFirstResult(0)->setMaxResults($numberOfItems);
        
        $persons = $qb->getQuery()->getResult();
        
        // get some custom field when the view is overriden and we want to 
        // show some custom field in the overriden view.
        $cfields = array();
        if (isset($config['custom_fields'])) {
            if (count($config['custom_fields']) > 0) {
                $cfs = $this->entityManager
                        ->getRepository('ChillCustomFieldsBundle:CustomField')
                        ->findBy(array('slug' => $config['custom_fields']));
                // store the custom fields in a array
                foreach($cfs as $cf) {
                    $cfields[$cf->getSlug()] = $cf;
                }
            }
        } 

        return $env->render(
            'ChillPersonBundle:Widget:homepage_person_list.html.twig',
            array(
                'persons' => $persons,
                'customFields' => $cfields
                
                )
            );
    }
    
    /**
     * 
     * @return UserInterface
     * @throws \RuntimeException
     */
    private function getUser()
    {
        $token = $this->tokenStorage->getToken();
        
        if ($token === null) {
            throw new \RuntimeException("the token should not be null");
        }
        
        $user = $token->getUser();
        
        if (!$user instanceof UserInterface || $user == null) {
            throw new \RuntimeException("the user should implement UserInterface. "
                    . "Are you logged in ?");
        }
        
        return $user;
    }

}