<?php

/*

 * This file is part of the Pagerfanta package.

 *

 * (c) Pablo Díez <pablodip@gmail.com>

 *

 * For the full copyright and license information, please view the LICENSE

 * file that was distributed with this source code.

 */

namespace Pagerfanta\Adapter;

use Doctrine\ORM\QueryBuilder;

use Doctrine\ORM\Query;

use Doctrine\ORM\NoResultException;

/**

 * DoctrineORMAdapter.

 *

 * @author Pablo Díez <pablodip@gmail.com>

 * @author Benjamin Eberlei <kontakt@beberlei.de>

 *

 * @api

 */

class DoctrineORMAdapter implements AdapterInterface

{

    /**

     * @var Query

     */

    private $query;

    private $fetchJoinCollection;

    /**

     * Constructor.

     *

     * @param Query|QueryBuilder $query               A Doctrine ORM query or query builder.

     * @param Boolean            $fetchJoinCollection Whether the query joins a collection (false by default).

     *

     * @api

     */

    public function __construct($query, $fetchJoinCollection = false)

    {

        if ($query instanceof QueryBuilder) {

            $query = $query->getQuery();

        }

        $this->query = $query;

        $this->fetchJoinCollection = (Boolean) $fetchJoinCollection;

    }

    /**

     * Returns the query

     *

     * @return Query

     *

     * @api

     */

    public function getQuery()

    {

        return $this->query;

    }

    /**

     * Returns whether the query joins a collection.

     *

     * @return Boolean Whether the query joins a collection.

     */

    public function getFetchJoinCollection()

    {

        return $this->fetchJoinCollection;

    }

    /**

     * {@inheritdoc}

     */

    public function getNbResults()

    {

        /* @var $countQuery Query */

        $countQuery = $this->cloneQuery($this->query);

        $countQuery->setHint(Query::HINT_CUSTOM_TREE_WALKERS, array('Pagerfanta\Adapter\DoctrineORM\CountWalker'));

        $countQuery->setFirstResult(null)->setMaxResults(null);

        try {

            $data =  $countQuery->getScalarResult();

            $data = array_map('current', $data);

            return array_sum($data);

        } catch(NoResultException $e) {

            return 0;

        }

    }

    /**

     * {@inheritdoc}

     */

    public function getSlice($offset, $length)

    {

        if ($this->fetchJoinCollection) {

            $subQuery = $this->cloneQuery($this->query);

            $subQuery->setHint(Query::HINT_CUSTOM_TREE_WALKERS, array('Pagerfanta\Adapter\DoctrineORM\LimitSubqueryWalker'))

                ->setFirstResult($offset)

                ->setMaxResults($length);

            $ids = array_map('current', $subQuery->getScalarResult());

            $whereInQuery = $this->cloneQuery($this->query);

            // don't do this for an empty id array

            if (count($ids) > 0) {

                $namespace = 'pg_';

                $whereInQuery->setHint(Query::HINT_CUSTOM_TREE_WALKERS, array('Pagerfanta\Adapter\DoctrineORM\WhereInWalker'));

                $whereInQuery->setHint('id.count', count($ids));

                $whereInQuery->setHint('pg.ns', $namespace);

                $whereInQuery->setFirstResult(null)->setMaxResults(null);

                foreach ($ids as $i => $id) {

                    $i++;

                    $whereInQuery->setParameter("{$namespace}_{$i}", $id);

                }

            }

            return $whereInQuery->getResult($this->query->getHydrationMode());

        }

        return $this->cloneQuery($this->query)

            ->setMaxResults($length)

            ->setFirstResult($offset)

            ->getResult($this->query->getHydrationMode())

        ;

    }

    /**

     * Clones a query.

     *

     * @param Query $query The query.

     *

     * @return Query The cloned query.

     */

    private function cloneQuery(Query $query)

    {

        /* @var $cloneQuery Query */

        $cloneQuery = clone $query;

        $cloneQuery->setParameters($query->getParameters());

        foreach ($query->getHints() as $name => $value) {

            $cloneQuery->setHint($name, $value);

        }

        return $cloneQuery;

    }

}