<?php

namespace Illuminate\Database;

use Closure;
use Exception;
use Throwable;
use Doctrine\DBAL\Driver\PDOSqlsrv\Driver as DoctrineDriver;
use Illuminate\Database\Query\Processors\SqlServerProcessor;
use Illuminate\Database\Query\Grammars\SqlServerGrammar as QueryGrammar;
use Illuminate\Database\Schema\Grammars\SqlServerGrammar as SchemaGrammar;

class SqlServerConnection extends Connection
{
    /**
     * Execute a Closure within a transaction.
     *
     * @param  \Closure  $callback
     * @return mixed
     *
     * @throws \Throwable
     */
    public function transaction(Closure $callback)
    {
        if ($this->getDriverName() == 'sqlsrv') {
            return parent::transaction($callback);
        }

        $this->pdo->exec('BEGIN TRAN');

        // We'll simply execute the given callback within a try / catch block
        // and if we catch any exception we can rollback the transaction
        // so that none of the changes are persisted to the database.
        try {
            $result = $callback($this);

            $this->pdo->exec('COMMIT TRAN');
        }

        // If we catch an exception, we will roll back so nothing gets messed
        // up in the database. Then we'll re-throw the exception so it can
        // be handled how the developer sees fit for their applications.
        catch (Exception $e) {
            $this->pdo->exec('ROLLBACK TRAN');

            throw $e;
        } catch (Throwable $e) {
            $this->pdo->exec('ROLLBACK TRAN');

            throw $e;
        }

        return $result;
    }

    /**
     * Get the default query grammar instance.
     *
     * @return \Illuminate\Database\Query\Grammars\SqlServerGrammar
     */
    protected function getDefaultQueryGrammar()
    {
        return $this->withTablePrefix(new QueryGrammar);
    }

    /**
     * Get the default schema grammar instance.
     *
     * @return \Illuminate\Database\Schema\Grammars\SqlServerGrammar
     */
    protected function getDefaultSchemaGrammar()
    {
        return $this->withTablePrefix(new SchemaGrammar);
    }

    /**
     * Get the default post processor instance.
     *
     * @return \Illuminate\Database\Query\Processors\SqlServerProcessor
     */
    protected function getDefaultPostProcessor()
    {
        return new SqlServerProcessor;
    }

    /**
     * Get the Doctrine DBAL driver.
     *
     * @return \Doctrine\DBAL\Driver\PDOSqlsrv\Driver
     */
    protected function getDoctrineDriver()
    {
        return new DoctrineDriver;
    }
}
