<?php

namespace Schema;

use Schema\Db\Table as Table;

use Schema\Db\Adapter\PostgresAdapter;
use Schema\Db\Adapter\MysqlAdapter;
use Schema\Db\Adapter\SQLiteAdapter;
use Schema\Db\Adapter\SqlServerAdapter;

class Wrapper{

    private static $_instance;

    public $_adapter;
    public $_driver;

    function __construct(){ }

    //SINGLETON==============================================
    private static function newObj(){
        if (!isset(self::$_instance)) {
            self::$_instance = new Wrapper();
        }
        return self::$_instance;
    }

    public static function getInstance(){
        if (!isset(self::$_instance)) {
            return self::newObj();
        }
        return self::$_instance;
    }
    //=======================================================

    public static function set_driver(\PDO $driver){
        $instance = self::getInstance();
        $instance->_driver = $driver;

        switch ($driver->getAttribute(\PDO::ATTR_DRIVER_NAME)){
            case 'sqlite':
                $instance->_adapter = new SQLiteAdapter();
                $instance-> _adapter->setConnection($driver);
                break;
            case 'pgsql':
                $instance->_adapter = new PostgresAdapter();
                $instance->_adapter->setConnection($driver);
                break;
            case 'mysql':
                break;

            default:
                break;
        }
    }

    public static function get_table($name){
        $instance = self::getInstance();
        
        if( $instance->_adapter->getConnection()->prefix ){
            $name = $instance->_adapter->getConnection()->prefix . $name;
        }
        
        return new Table($name, Array(), $instance->_adapter);
    }

    public static function begin(){
        $instance = self::getInstance();
        $instance->_adapter->beginTransaction();
    }

    public static function commit(){
        $instance = self::getInstance();
        $instance->_adapter->commitTransaction();
    }

    public static function exec($sql){
        $instance = self::getInstance();
        $prefix = $instance->_adapter->getConnection()->prefix;
        $sql = preg_replace('/{(.*)}/', "$prefix$1", $sql);
        $instance->_driver->exec($sql);
    }

}