<?
/*
 * This is parametric class implementation mainly developed by hide@address.com It allows you to exclude
 * actual values from the queries and specify them inside parameter array. Some database drivers
 * may cache queries better when values are passed as parametrs. Also, using parameters gives you an
 * additional security layer, since they are always quoted properly and types are enforced.
 */
class DBlite_psql extends DBlite_sql {
    function parseParamType($type, $name, $value){
        switch ($type) {
            case 'str':
                return (is_null($value))?'null':"'".str_replace("'", "''", $value)."'";
            case 'plain':
            case 'sub':
                return $value;
            case 'int':
                if((!is_null($value)) and ($value==='')){
                    return $this->error('NOT set value ("'.$value.'") for numeric parameter "'.$name.'"', $this->last_query);
                }
                return (is_null($value))?'null':$value;
            default:
                return $this->error('PARSE PARAMS ERROR: Unknown parameter type: "'.$type.'" for parameter "'.$name.'"', $this->last_query);
        }
    }
    /*
    function parseParamType($type, $name, $value) {
        switch ($type) {
            case 'str':
                //return (is_null($value))?'null':"'".str_replace("'","''",str_replace("\'","\\\\'",$value))."'";
                return (is_null($value))?'null':"'".mysql_real_escape_string($value)."'";
                break;
            case 'date':
                if ((!is_null($value)) and ($value=='')) {
                    return $this->error('NOT set value for DATE parameter "'.$name.'"', $this->last_query);
                }
                if (is_numeric($value)) {
                    $value = date('Y-m-d H:i:s',$value);
                }
                return (is_null($value))?'null':"'".$value."'";
                break;
            default:
                return parent::parseParamType($type, $name, $value);
        }
    }
    */
    function parseParamValues($params) {
        $res = array();
        foreach ($params as $param_name => $param_value) {
            $pn_parts = explode(' ', trim($param_name));
            $pn_type = (count($pn_parts)==1)?'str':$pn_parts[0];
            $pn_name = $pn_parts[count($pn_parts)-1];

            if (($res[$pn_name] = $this->parseParamType($pn_type, $pn_name, $param_value))===false) {
                return false;
            }
        }
        return $res;
    }
    function _charpos($haystack, $needle) {
        // search nearest delimiter
        $res = false;
        $pos_math = array();
        for ($i=0;$i<strlen($needle);$i++) {
            $pos = strpos($haystack, $needle[$i]);
            if ($pos!=false) $pos_math[]= $pos;
        }
        if ($pos_math != array()) {
            $res = $pos_math[0];
            foreach ($pos_math as $it) if ($res > $it) $res = $it;
        }

        return $res;
    }
    function parseParamQuery($query) {
        if (!is_array($query)) {
            return $query;
        } else {

                // check ? - type params
                if (strpos($query['query'], '?')!==false) {
                    $params = $query['params'];
                    $qry = $query['query'];
                    $tmp = array_keys($params);
                    if (($tmp[0]===0) and ($tmp[count($tmp)-1]===count($tmp)-1)) {
                        $i=0;
                        $newpars = array();
                        while(($pos = strpos($qry, '?'))!==false) {
                           $qry = substr_replace($qry, ':p'.$i, $pos, 1);
                           $newpars['p'.$i] = $params[$tmp[$i]];
                           $i++;
                        }


                        $query['query'] = $qry;
                        $query['params'] = $newpars;
                    }
                }

                //
            if (!$parsedParams = $this->parseParamValues($query['params'])) {
                return false;
            } else {
                $this->last_query['query_str'] = $query['query'];
                $this->last_query['params'] = $query['params'];
                // find parameters in query string
                $string = $query['query'];
                $query_parts = array();
                $delim = ':';
                $pos = DBlite::_charpos($string, $delim);
                while (($pos!=false) and ($string!='')) {
                    $query_parts[] = substr($string, 0, $pos);
                    $string = substr($string, $pos);
                    if ($delim == ':') {
                        $delim = " \n\t, )+-";
                    }
                    else {
                        $delim = ':';
                    }
                    $pos=DBlite::_charpos($string, $delim);
                }
                $query_parts[] = $string;

                // if query['allow_extra'] not empty - allow params not in query
                $allow_extra = !empty($query['allow_extra']);

                // create array with found params
                $params_in_query = array();
                foreach ($query_parts as $key=>$q_part) {
                    if (substr($q_part, 0, 1)==':') {
                        $par_uname = strtoupper(substr($q_part, 1));
                        if (!isset($params_in_query[$par_uname]['q_part'])) {
                            $params_in_query[$par_uname]['q_part'] = array();
                        }
                        array_push($params_in_query[$par_uname]['q_part'], $key);
                    }
                }

                // set parameter values and test for complete parameter list
                foreach ($parsedParams as $param_name => $param_value) {
                    if (!array_key_exists(strtoupper($param_name), $params_in_query) and !$allow_extra) {

                        $p = array();
                        foreach (array_keys($params_in_query) as $it) {
                            $p[]='"'.$it.'"';
                        }
                        $this->last_query['params_in_query'] = implode(', ', $p);
                        return $this->error('PARSE PARAMS ERROR: Not found parameter "'.$param_name.'" in query.', $this->last_query);
                    } else {
                        if (isset($params_in_query[strtoupper($param_name)]['value'])) {
                            return $this->error('PARSE PARAMS ERROR: Double parameters found "'.$param_name.'"', $this->last_query);
                        } else {
                            $params_in_query[strtoupper($param_name)]['value'] = $param_value;
                        }
                    }
                }

                // assing parameters values to part_query array
                foreach ($params_in_query as $par_key=>$par_item) {
                    if (isset($par_item['q_part']))
                    foreach ($par_item['q_part'] as $q_part_key) {
                        if (isset($par_item['value'])) {
                            $query_parts[$q_part_key] = $par_item['value'];
                        } else {
                            $query_parts[$q_part_key] = $par_item['value'];
                        }
                    }
                }

                // construct query
                return implode('', $query_parts);
            }
        }
    }
}