<?php

//
// +----------------------------------------------------------------------+
// | PHP version 4.0                                                      |
// +----------------------------------------------------------------------+
// | Copyright (c) 1997-2001 The PHP Group                                |
// +----------------------------------------------------------------------+
// | This source file is subject to version 2.02 of the PHP license,      |
// | that is bundled with this package in the file LICENSE, and is        |
// | available at through the world-wide-web at                           |
// | http://www.php.net/license/2_02.txt.                                 |
// | If you did not receive a copy of the PHP license and are unable to   |
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// | license@php.net so we can mail you a copy immediately.               |
// +----------------------------------------------------------------------+
// | Authors: Stig Bakken <ssb@fast.no>                                   |
// |          Jan Dankert <phpdb@jandankert.de>                           |
// +----------------------------------------------------------------------+
//

/**
 * Datenbank-abhaengige Methoden fuer PDO.
 * 
 * @author Jan Dankert
 * @version $Revision: 1.5 $
 * @package openrat.database
 */
class DB_pdo
{
    /**
     * Die PDO-Verbindung.
     *
     * @var Resource
     */
    var $connection;
    
    /**
     * Datenbank-Fehler.
     *
     * @var String
     */
    var $error;
    
    var $prepared = false;
    
    var $lowercase = false;


    function connect( $conf )
    {
        $url    = $conf['dsn'     ];
        $user   = $conf['user'    ];
        $pw     = $conf['password'];
        
        if    ( isset($conf['convert_to_lowercase']) && $conf['convert_to_lowercase'] )
            $this->lowercase = true;
        
        $options = array();
        foreach( $conf as $c )
            if    ( substr($c,0,7) == 'option_' )
                $options[substr($c,8)] = $conf[$c];
                
        $this->connection = new PDO($url, $user, $pw, $options);
        
        if    ( !is_object($this->connection) )
        {
            $this->error = "Could not connect to database on host $host. ".PDO::errorInfo();
            return false;
        }
                
        return true;
    }



    function disconnect()
    {
        $this->connection = null;
        return true;
    }



    function query($query)
    {
        if    ( $this->prepared )
        {
            $ar     = array();
                
            foreach( $query->data as $val )
                $ar[] = $val['value'];
            $erg = $this->stmt->execute( $ar );

            if    ( $erg === false  )
            {
                die( 'Could not execute prepared statement "'.$query->query.'" with values "'.implode(',',$ar).'": '.implode('/',$this->connection->errorInfo()) );
            }
            
            return $this->stmt;
        }
        else
        {
            $this->result = $this->connection->query($query);
    
            if    ( ! $this->result )
            {
                $this->error = 'Database error: '.implode('/',$this->connection->errorInfo());
                return FALSE;
            }
            return $this->result;
        }
    }


    function fetchRow( $result, $rownum )
    {
        if    ( $this->prepared )
            $row = $this->stmt->fetch( PDO::FETCH_ASSOC );
        else
            $row = $this->result->fetch( PDO::FETCH_ASSOC );
        
        if    ( is_array($row) && $this->lowercase )
            $row = array_change_key_case($row);
                
        return $row;
    }

 
    function freeResult($result)
    {
        return true;
    }


    function prepare( $query,$param)
    {
        $offset = 0;
        foreach( $param as $pos)
        {
            foreach( $pos as $posx )
            {
                $posx += $offset++;
                $query = substr($query,0,$posx).'?'.substr($query,$posx);
            }
        }

        $this->prepared = true;
        $this->stmt = $this->connection->prepare($query);
        
        if    ( $this->stmt === false )
            die( 'Database error: '.implode('/',$this->connection->errorInfo()) );
        
    }

    
    
    function bind( $param,$value )
    {
        $this->params[$param] = $value;
    }
    
    
    
    /**
     * Startet eine Transaktion.
     */
    function start()
    {
        $this->connection->beginTransaction();
    }

    
    
    /**
     * Beendet eine Transaktion.
     */
    function commit()
    {
        $this->connection->commit();
    }


    /**
     * Bricht eine Transaktion ab.
     */
    function rollback()
    {
        $this->connection->rollBack();
    }
    
    
    
    /**
     * Setzt die letzte Abfrage zurueck.
     */
    function clear()
    {
        $this->prepared = false;
        $this->params   = array();
    }


    /**
     * Why this? See http://e-mats.org/2008/07/fatal-error-exception-thrown-without-a-stack-frame-in-unknown-on-line-0/
     * 
     * @return array
     */
    function __sleep() {
        return array();
  }  
    
}

?>