<?php
/*
 *  $Id$
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * This software consists of voluntary contributions made by many individuals
 * and is licensed under the LGPL. For more information, see
 * <http://www.doctrine-project.org>.
 */

namespace Doctrine\ORM\Persisters;

use Doctrine\ORM\PersistentCollection;

/**
 * Persister for many-to-many collections.
 *
 * @author Roman Borschel <roman@code-factory.org>
 * @since 2.0
 */
class ManyToManyPersister extends AbstractCollectionPersister
{
    /**
     * {@inheritdoc}
     *
     * @override
     */
    protected function _getDeleteRowSql(PersistentCollection $coll)
    {
        $mapping = $coll->getMapping();
        $joinTable = $mapping->joinTable;
        $columns = $mapping->joinTableColumns;
        return 'DELETE FROM ' . $joinTable['name'] . ' WHERE ' . implode(' = ? AND ', $columns) . ' = ?';
    }

    /**
     * {@inheritdoc}
     *
     * @override
     * @internal Order of the parameters must be the same as the order of the columns in
     *           _getDeleteRowSql.
     */
    protected function _getDeleteRowSqlParameters(PersistentCollection $coll, $element)
    {
        return $this->_collectJoinTableColumnParameters($coll, $element);
    }

    /**
     * {@inheritdoc}
     *
     * @override
     */
    protected function _getUpdateRowSql(PersistentCollection $coll)
    {}

    /**
     * {@inheritdoc}
     *
     * @override
     * @internal Order of the parameters must be the same as the order of the columns in
     *           _getInsertRowSql.
     */
    protected function _getInsertRowSql(PersistentCollection $coll)
    {
        $mapping = $coll->getMapping();
        $joinTable = $mapping->joinTable;
        $columns = $mapping->joinTableColumns;
        return 'INSERT INTO ' . $joinTable['name'] . ' (' . implode(', ', $columns) . ')'
                . ' VALUES (' . implode(', ', array_fill(0, count($columns), '?')) . ')';
    }

    /**
     * {@inheritdoc}
     *
     * @override
     * @internal Order of the parameters must be the same as the order of the columns in
     *           _getInsertRowSql.
     */
    protected function _getInsertRowSqlParameters(PersistentCollection $coll, $element)
    {
        return $this->_collectJoinTableColumnParameters($coll, $element);
    }
    
    /**
     * Collects the parameters for inserting/deleting on the join table in the order
     * of the join table columns as specified in ManyToManyMapping#joinTableColumns.
     *
     * @param $coll
     * @param $element
     * @return array
     */
    private function _collectJoinTableColumnParameters(PersistentCollection $coll, $element)
    {
        $params = array();
        $mapping = $coll->getMapping();
        $isComposite = count($mapping->joinTableColumns) > 2;
        
        $identifier1 = $this->_uow->getEntityIdentifier($coll->getOwner());
        $identifier2 = $this->_uow->getEntityIdentifier($element);
        
        if ($isComposite) {
            $class1 = $this->_em->getClassMetadata(get_class($coll->getOwner()));
            $class2 = $coll->getTypeClass();
        }
        
        foreach ($mapping->joinTableColumns as $joinTableColumn) {
            if (isset($mapping->relationToSourceKeyColumns[$joinTableColumn])) {
                if ($isComposite) {
                    $params[] = $identifier1[$class1->fieldNames[$mapping->relationToSourceKeyColumns[$joinTableColumn]]];
                } else {
                    $params[] = array_pop($identifier1);
                }
            } else {
                if ($isComposite) {
                    $params[] = $identifier2[$class2->fieldNames[$mapping->relationToTargetKeyColumns[$joinTableColumn]]];
                } else {
                    $params[] = array_pop($identifier2);
                }
            }
        }

        return $params;
    }

    /**
     * {@inheritdoc}
     *
     * @override
     */
    protected function _getDeleteSql(PersistentCollection $coll)
    {
        $mapping = $coll->getMapping();
        $joinTable = $mapping->joinTable;
        $whereClause = '';
        foreach ($mapping->relationToSourceKeyColumns as $relationColumn => $srcColumn) {
            if ($whereClause !== '') $whereClause .= ' AND ';
            $whereClause .= "$relationColumn = ?";
        }
        return 'DELETE FROM ' . $joinTable['name'] . ' WHERE ' . $whereClause;
    }

    /**
     * {@inheritdoc}
     *
     * @override
     * @internal Order of the parameters must be the same as the order of the columns in
     *           _getDeleteSql.
     */
    protected function _getDeleteSqlParameters(PersistentCollection $coll)
    {
        $params = array();
        $mapping = $coll->getMapping();
        $identifier = $this->_uow->getEntityIdentifier($coll->getOwner());
        if (count($mapping->relationToSourceKeyColumns) > 1) {
            $sourceClass = $this->_em->getClassMetadata(get_class($mapping->getOwner()));
            foreach ($mapping->relationToSourceKeyColumns as $relColumn => $srcColumn) {
                $params[] = $identifier[$sourceClass->fieldNames[$srcColumn]];
            }
        } else {
           $params[] = array_pop($identifier);
        }
        
        return $params;
    }
}