<?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   |
// | obtain it through the world-wide-web, please send a note to          |
// | 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 MySQL 
 * @author $Author: dankert $
 * @version $Revision: 1.5 $
 * @package openrat.database
 */
class DB_mysqli
{
    /**
     * Die MySql-Verbindung.
     *
     * @var Resource
     */
    var $connection;
    
    /**
     * Datenbank-Fehler.
     *
     * @var String
     */
    var $error;
    
    /**
     * SQL-Statement (nur fuer prepared-Statements).
     * @var Resource
     */
    var $stmt;

    var $prepared = false;
    var $params = array();


    function connect( $conf )
    {
        $host   = $conf['host'];
        $user   = $conf['user'];
        $pw     = $conf['password'];
        $db     = $conf['database'];
        $host = '127.0.0.1';
        
        if    ( isset($conf['port']) )
            $host .= ':'.$conf['port'];

        // 5.3.0 - Added the ability of persistent connections. 
        if   ( $conf['persistent'] && version_compare(PHP_VERSION, '5.3.0', '>') )
            $host = 'p:'.$host; // Prepending host by p: opens a persistent connection.
        
        $connect_function = 'mysqli_connect';

        if    ( $pw != '' )
            $this->connection = $connect_function( $host,$user,$pw );
        elseif ( $user != '' ) 
            $this->connection = $connect_function( $host,$user );
        elseif ( $host != '' ) 
            $this->connection = $connect_function( $host );
        else 
            $this->connection = $connect_function();

        #print_r($this->connection);
        
        if    ( false && !is_object($this->connection) )
        {
            $this->error = "Could not connect to mysqli-database on host $host.";
            return false;
        }
                
        if    ( $db != '' )
        {
            if    ( !mysqli_select_db( $this->connection,$db ) )
            {
                $this->error = "Could not select database '$db' on host $host.";
                return false;
            }
        }

        return true;
    }



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



    function query($query)
    {
        if    ( $this->prepared )
        {
            $ar     = array();
            $ar[-1] = $this->stmt;
            $ar[0]  = '';
            
            foreach($this->params as $name => $data)
            {
                switch( $data['type'] )
                {
                    case 'int':
                        $ar[0] .= 'i';
                        break;
                    case 'string':
                        $ar[0] .= 's';
                        break;
                    default:
                        die('mysqli: unknown data type: '.$data['type']);
                }
                
                $ar[] = &$data['value'];
            }
        
            call_user_func_array('mysqli_stmt_bind_param',$ar);
            $this->stmt->execute();
            return $this->stmt;
        }
        
        $result = mysqli_query($this->connection,$query);

        if    ( ! $result )
        {
            $this->error = 'Database error: '.mysql_error();
            return FALSE;
        }

        return $result;
    }


    function fetchRow( $result, $rownum )
    {
        if    ( $this->prepared )
        {
            $result = $this->stmt->result_metadata();
            $fields = array();
            while ($field = mysqli_fetch_field($result)) {
                $name = $field->name;
                $fields[$name] = &$$name;
            }
            array_unshift($fields, $this->stmt);
            call_user_func_array('mysqli_stmt_bind_result', $fields);
            
            array_shift($fields);
            if    ( mysqli_stmt_fetch($this->stmt) )
            {
                $temp = array();
                foreach($fields as $key => $val)
                    $temp[$key] = $val;
                //array_push($results, $temp);
                return $temp;
            }
            else
            {
                mysqli_stmt_close($this->stmt);
                $this->stmt = null; 
                return false;
            }
        }
        else
        {
            // Plain old flat query
            $row = $result->fetch_assoc();
            return $row;
        }
    }

 
    function freeResult($result)
    {
        if    ( is_resource($result) )
            return mysqli_free_result($result);
        return true;
    }



    function prepare( $query,$param)
    {
        if    ( is_object($this->stmt) )
        {
            mysqli_stmt_close($this->stmt);
            $this->stmt = null;
        }
        
        $offset = 0;
        foreach( $param as $pos)
        {
            foreach( $pos as $posn )
            {
                $posn += $offset++;
                $query = substr($query,0,$posn).'?'.substr($query,$posn);
            }
        }

        $this->stmt = mysqli_prepare($this->connection,$query);
        if    ( $this->stmt === FALSE )
            die( 'Mysql-I is unable to prepare the statement: '.$query.' : '.mysqli_error($this->connection) );
        $this->prepared = true;
    }
    
    function bind( $param,$value )
    {
        $this->params[$param] = $value;
    }
    
    
        /**
     * Startet eine Transaktion.
     */
    function start()
    {
        mysqli_query($this->connection,'BEGIN');
    }


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


    /**
     * Bricht eine Transaktion ab.
     */
    function rollback()
    {
        mysqli_query($this->connection,'ROLLBACK');
    }
    

    /**
     * Setzt die letzte Abfrage zurueck.
     */
    function clear()
    {
        $this->prepared = false;
        $this->params   = array();
    }
    
}

?>