php interface Aspire_Dbo_Statement function __construct initialQuery i

<?php
interface Aspire_Dbo_Statement
{
    function __construct($initialQuery, $initialParameters = null);
    function exec($parameters = null);
    function fetch($fetchType = Aspire_Dbo::FETCH_ASSOC);
    function fetchAll($fetchType = Aspire_Dbo::FETCH_ASSOC);
    function fetchEntity($sender);
    function fetchAllEntitys($sender);
}

class Aspire_Dbo_Mysql_Statement implements Aspire_Dbo_Statement
{
    private $initialQuery = null;
    private $query = null;
    private $queryResult = null;

    function __construct($initialQuery, $initialParameters = null)
    {
        $this->initialQuery = $initialQuery;
        if ($initialParameters !== null) {
            $this->query = $this->prepareQuery($initialParameters);
        }
    }

    private function prepareQuery($parameters)
    {
        $resultingQuery = '';
        $query = $this->initialQuery;
        $qlen = strlen($query);
        $lastBlock = 0;
        $ptr = 0;
        $lastParam = 0;

        while ($ptr < $qlen) {
            if ($query[$ptr] == ':') {
                $ptr++;
                $pstart = $ptr;
                while($ptr < $qlen && ctype_alnum($query[$ptr])) {
                    $ptr++;
                }
                $paramId = substr($query, $pstart, $ptr - $pstart);

                if (isset($parameters[$paramId])) {
                    $pstrLen = strlen($paramId);
                    $paramValue = $this->parseParameter($parameters[$paramId]);
                    $resultingQuery .= substr($query, $lastBlock, $ptr - $lastBlock - $pstrLen - 1);
                    $resultingQuery .= $paramValue;
                    $lastBlock = $ptr;
                } else {
                    Aspire_Log::log('Undefined parameter ' . $paramId, Aspire_Log::Error);
                    return false;
                }
            } else if ($query[$ptr] == '?') {
                if ($lastParam <= count($parameters)) {
                    $paramValue = $this->parseParameter($parameters[$lastParam]);
                    $resultingQuery .= substr($query, $lastBlock, $ptr - $lastBlock);
                    $resultingQuery .= $paramValue;
                    $lastBlock = $ptr + 1;
                    $lastParam++;
                } else {
                    Aspire_Log::log('Undefined parameter #' . $lastParam, Aspire_Log::Error);
                    return false;
                }
            }
            $ptr++;
        }

        return $resultingQuery;
    }

    private function parseParameter($param)
    {
        $paramValue = '';

        switch ($param[1]) {
            case Aspire_Dbo::PARAM_KEY:
                $paramValue = '`' . mysql_real_escape_string($param[0]) . '`';
                break;

            case Aspire_Dbo::PARAM_STR:
                $paramValue = '\'' . mysql_real_escape_string($param[0]) . '\'';
                break;

            case Aspire_Dbo::PARAM_INT:
                $paramValue = intval($param[0]);
                break;

            default:
                $paramValue = $param[0];
                break;
        }

        return $paramValue;
    }

    /**
     * Executes query and returns affected rows
     */
    function exec($parameters = null)
    {
        if ($parameters !== null) {
            $this->query = $this->prepareQuery($parameters);
        }
        $this->queryResult = @mysql_query($this->query);

        if ($this->queryResult !== false) {
            return true;
        } else {
            Aspire_Log::log('Query failed: ' . $this->query . '; ' . mysql_error(), Aspire_Log::Error);
            return false;
        }
    }

    private function getFetchFunction($fetchType)
    {
        switch ($fetchType)
        {
            case Aspire_Dbo::FETCH_ARRAY:
                return 'mysql_fetch_array';
                break;

            case Aspire_Dbo::FETCH_OBJECT:
                return 'mysql_fetch_object';
                break;

            default:
                return 'mysql_fetch_assoc';
                break;
        }
    }

    function fetchAll($fetchType = Aspire_Dbo::FETCH_ASSOC)
    {
        if (!$this->queryResult) {
            return false;
        }
        $results = array();
        $fetchFunc = $this->getFetchFunction($fetchType);

        while ($r = $fetchFunc($this->queryResult)) {
            $results[] = $r;
        }

        return $results;
    }

    function fetch($fetchType = Aspire_Dbo::FETCH_ASSOC)
    {
        if (!$this->queryResult) {
            return false;
        }

        $fetchFunc = $this->getFetchFunction($fetchType);

        return $fetchFunc($this->queryResult);
    }

    function fetchEntity($sender)
    {
        if (!$this->queryResult) {
            return false;
        }

        $entityClass = Aspire_Model::getEntityClass($sender);

        return new $entityClass($this->fetch(Aspire_Dbo::FETCH_ASSOC));
    }

    function fetchAllEntitys($sender)
    {
        if (!$this->queryResult) {
            return false;
        }

        $entityClass = Aspire_Model::getEntityClass($sender);
        $results = array();

        while ($r = mysql_fetch_assoc($this->queryResult)) {
            $results[] = new $entityClass($r);
        }

        return $results;
    }
}