<?
class DBlite_debug extends DBlite_mysql {
    private $_tracing = false;  // trace all SQL queries
    private $_tracing_file_handle;


    function start_tracing($filename = null) {
        if (is_null($filename))
            $filename = dirname(__FILE__).'/trace.log';
        $this->_tracing_file_handle = fopen($filename,'a');
        if ($this->_tracing_file_handle) {
            $this->_tracing = true;
        }
        else {
            if ($this->echo_errors)
                echo '<b>Cannot open file "'.$filename.'" for write!</b><br />';
        }
    }
    function stop_tracing() {
        if ($this->_tracing and $this->_tracing_file_handle)
            fclose($this->_tracing_file_handle);
        $this->_tracing = false;
    }

    function datetime($dts) {
        return array(
                      'DAY'=>substr($dts, 8,2),
                      'MONTH'=>substr($dts,5,2),
                      'YEAR'=> substr($dts,0,4),
                      'HOUR'=>substr($dts,11,2),
                      'MIN'=>substr($dts,14,2),
                      'SEC'=>substr($dts,17,2)
                     );
    }
    // 2004-10-23 10:59:16
    function dts2tms($dts) {
        $dtime = $this->datetime($dts);
        return mktime($dtime['HOUR'], $dtime['MIN'], $dtime['SEC'],
                      $dtime['MONTH'], $dtime['DAY'], $dtime['YEAR']);
    }

	function _microtime_float($mctime) {
	    list($usec, $sec) = explode(" ", $mctime);
	    return ((float)$usec + (float)$sec);
	}
    function _trace_query($query,$start_time, $finish_time) {
        if ($this->_tracing and $this->_tracing_file_handle) {
            @fwrite($this->_tracing_file_handle, ' ******** '. date('d.m.Y H:i:s') . " ********\n".
                 "\n". $this->_format_query($query) . "\n" .
                 "\n".$this->_explain_query($query)."\n".
                 'Open cursor time: '.round((($this->_microtime_float($finish_time)-$this->_microtime_float($start_time))*1000)).' ms'.
                 "\n\n");
        }
    }
    function _format_query($query) {
        if ((strpos($query,"\n")===false) and (strlen($query)>80)) {
            $res = str_replace(array(' FROM ',
                                     ' from ',
                                     ' inner join ',
                                     ' INNER JOIN ',
                                     ' left outer join ',
                                     ' LEFT OUTER JOIN ',
                                     ' LEFT JOIN ',
                                     ' left join ',
                                     ' JOIN ',
                                     ' join ',
                                     ' where ',
                                     ' WHERE ',
                                     ' and ',
                                     ' AND ',
                                     ' or ',
                                     ' OR ',
                                     ' GROUP BY ',
                                     ' group by ',
                                     ' ORDER BY ',
                                     ' order by ',
                                     ' HAVING ',
                                     ' having ',
                                     ' LIMIT ',
                                     ' limit ',
                                     'select ',
                                     'SELECT '),
                               array("\n;;;;;;;;;;;FROM;",
                                     "\n;;;;;;;;;;;from;",
                                     "\n;;;;;inner;join;",
                                     "\n;;;;;INNER;JOIN;",
                                     "\nleft;outer;join;",
                                     "\nLEFT;OUTER;JOIN;",
                                     "\n;;;;;;LEFT;JOIN;",
                                     "\n;;;;;;left;join;",
                                     "\n;;;;;;;;;;;JOIN;",
                                     "\n;;;;;;;;;;;join;",
                                     "\n;;;;;;;;;;where;",
                                     "\n;;;;;;;;;;WHERE;",
                                     "\n;;;;;;;;;;;;and;",
                                     "\n;;;;;;;;;;;;AND;",
                                     "\n;;;;;;;;;;;;;or;",
                                     "\n;;;;;;;;;;;;;OR;",
                                     "\n;;;;;;;GROUP;BY;",
                                     "\n;;;;;;;group;by;",
                                     "\n;;;;;;;ORDER;BY;",
                                     "\n;;;;;;;order;by;",
                                     "\n;;;;;;;;;HAVING;",
                                     "\n;;;;;;;;;having;",
                                     "\n;;;;;;;;;;LIMIT;",
                                     "\n;;;;;;;;;;limit;",
                                     ";;;;;;;;;select;",
                                     ";;;;;;;;;SELECT;",
                                     ),
                               $query);
            $res = str_replace(';',' ',$res);
            $lines = explode("\n",$res);
            if ((strpos(strtoupper($lines[0]),'SELECT')!==false) and (strlen($lines[0])>80)) {
                $tmp_str = $lines[0];
                //$init_len = strlen($tmp_str); $new_len = 0;
                $new_str = str_replace('   ','  ',$tmp_str);
                while ($new_str != $tmp_str) {
                  $tmp_str = $new_str;
                  $new_str = str_replace('   ','  ',$tmp_str);
                }

                $fields = explode("\n",str_replace('  ',"\n                ",$new_str));
                $fields[1] = str_replace("                ",'         ',$fields[1]);
                unset($fields[0]);
                if (strlen(trim($fields[count($fields)]))==0) unset($fields[count($fields)]);
                $lines[0] = implode("\n",$fields);
                $res = implode("\n",$lines);
            }
        } else
            $res = $query;
        return $res;
    }
    function _explain_query($query) {
        if ($cursor = mysql_query('explain '.$query,$this->handle)) {
            if (mysql_num_rows($cursor) == 0) {
                return 'explain query not return rows!';
            }

            $rows = array();
            $max_lens = array();
            while ($row = mysql_fetch_assoc($cursor)) {
                $rows[] = $row;
                if (empty($max_lens)) {
                    foreach ($row as $name=>$value) {
                        $max_lens[$name] = strlen($name);
                        $col_names[$name] = $name;
                    }
                }
                foreach ($row as $name=>$value) {
                    $val = (isset($max_lens[$name])?$max_lens[$name]:0);
                    if ($val < strlen($value))
                        $max_lens[$name] = strlen($value);
                }
            }
            mysql_free_result($cursor);
            $res  = '';
            if (!empty($rows)) {
                $res .= $this->_plan_line(null,$max_lens);
                $res .= $this->_plan_line($col_names,$max_lens);
                $res .= $this->_plan_line(null,$max_lens);
                foreach ($rows as $row) {
                    $res .= $this->_plan_line($row,$max_lens);
                }
                $res .= $this->_plan_line(null,$max_lens);
            }
            return $res;
        }
        else {
            return 'Error explain query: '.mysql_error($this->handle);
        }
    }
    function _plan_line($text_arr,$max_lens) {
        $res = '';
        if (is_null($text_arr)) {
            // print delimiter line
            foreach ($max_lens as $key=>$len)
                $res .= '+'.str_pad('-',$len+2,'-');
            $res .= "+\n";
        }
        else {
            foreach ($text_arr as $name=>$val) {
                switch ($name) {
                    case 'key_len':
                    case 'rows':
                        $res .= '|'.str_pad($val.' ',$max_lens[$name]+2,' ',STR_PAD_LEFT);
                        break;
                    default:
                        $res .= '|'.str_pad(' '.$val,$max_lens[$name]+2);
                }
            }
            $res .= "|\n";
        }
        return $res;
    }

    function realQuery($query){
		$start_time = microtime();
        $result = parent::realQuery();
        $finish_time = microtime();

        // FIXME
        if ($this->_tracing and $this->cursor !==true) // exclude modify queries from explain
            $this->_trace_query($query,$start_time, $finish_time);
    }
}