<?php
/*
 * 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 MIT license. For more information, see
 * <http://www.doctrine-project.org>.
 */
namespace Doctrine\DBAL\Schema\Synchronizer;

use Doctrine\DBAL\Connection;
use Doctrine\DBAL\Schema\Schema;
use Doctrine\DBAL\Schema\Comparator;
use Doctrine\DBAL\Schema\Visitor\DropSchemaSqlCollector;

/**
 * Schema Synchronizer for Default DBAL Connection
 *
 * @author Benjamin Eberlei <kontakt@beberlei.de>
 */
class SingleDatabaseSynchronizer extends AbstractSchemaSynchronizer
{
    /**
     * @var Doctrine\DBAL\Platforms\AbstractPlatform
     */
    private $platform;

    public function __construct(Connection $conn)
    {
        parent::__construct($conn);
        $this->platform = $conn->getDatabasePlatform();
    }

    /**
     * Get the SQL statements that can be executed to create the schema.
     *
     * @param Schema $createSchema
     * @return array
     */
    public function getCreateSchema(Schema $createSchema)
    {
        return $createSchema->toSql($this->platform);
    }

    /**
     * Get the SQL Statements to update given schema with the underlying db.
     *
     * @param Schema $toSchema
     * @param bool $noDrops
     * @return array
     */
    public function getUpdateSchema(Schema $toSchema, $noDrops = false)
    {
        $comparator = new Comparator();
        $sm         = $this->conn->getSchemaManager();

        $fromSchema = $sm->createSchema();
        $schemaDiff = $comparator->compare($fromSchema, $toSchema);

        if ($noDrops) {
            return $schemaDiff->toSaveSql($this->platform);
        }

        return $schemaDiff->toSql($this->platform);
    }

    /**
     * Get the SQL Statements to drop the given schema from underlying db.
     *
     * @param Schema $dropSchema
     * @return array
     */
    public function getDropSchema(Schema $dropSchema)
    {
        $visitor    = new DropSchemaSqlCollector($this->platform);
        $sm         = $this->conn->getSchemaManager();

        $fullSchema = $sm->createSchema();

        foreach ($fullSchema->getTables() as $table) {
            if ( $dropSchema->hasTable($table->getName())) {
                $visitor->acceptTable($table);
            }

            foreach ($table->getForeignKeys() as $foreignKey) {
                if ( ! $dropSchema->hasTable($table->getName())) {
                    continue;
                }

                if ( ! $dropSchema->hasTable($foreignKey->getForeignTableName())) {
                    continue;
                }

                $visitor->acceptForeignKey($table, $foreignKey);
            }
        }

        if ( ! $this->platform->supportsSequences()) {
            return $visitor->getQueries();
        }

        foreach ($dropSchema->getSequences() as $sequence) {
            $visitor->acceptSequence($sequence);
        }

        foreach ($dropSchema->getTables() as $table) {
            /* @var $sequence Table */
            if ( ! $table->hasPrimaryKey()) {
                continue;
            }

            $columns = $table->getPrimaryKey()->getColumns();
            if (count($columns) > 1) {
                continue;
            }

            $checkSequence = $table->getName() . "_" . $columns[0] . "_seq";
            if ($fullSchema->hasSequence($checkSequence)) {
                $visitor->acceptSequence($fullSchema->getSequence($checkSequence));
            }
        }

        return $visitor->getQueries();
    }

    /**
     * Get the SQL statements to drop all schema assets from underlying db.
     *
     * @return array
     */
    public function getDropAllSchema()
    {
        $sm      = $this->conn->getSchemaManager();
        $visitor = new DropSchemaSqlCollector($this->platform);

        /* @var $schema \Doctrine\DBAL\Schema\Schema */
        $schema  = $sm->createSchema();
        $schema->visit($visitor);

        return $visitor->getQueries();
    }

    /**
     * Create the Schema
     *
     * @param Schema $createSchema
     * @return void
     */
    public function createSchema(Schema $createSchema)
    {
        $this->processSql($this->getCreateSchema($createSchema));
    }

    /**
     * Update the Schema to new schema version.
     *
     * @param Schema $toSchema
     * @param bool $noDrops
     * @return void
     */
    public function updateSchema(Schema $toSchema, $noDrops = false)
    {
        $this->processSql($this->getUpdateSchema($toSchema, $noDrops));
    }

    /**
     * Drop the given database schema from the underlying db.
     *
     * @param Schema $dropSchema
     * @return void
     */
    public function dropSchema(Schema $dropSchema)
    {
        $this->processSqlSafely($this->getDropSchema($dropSchema));
    }

    /**
     * Drop all assets from the underyling db.
     *
     * @return void
     */
    public function dropAllSchema()
    {
        $this->processSql($this->getDropAllSchema());
    }
}