<?php
// ************ RRD status class **************
class rrdstat {

  var $rrd_file = null;
  var $basename = null;

  var $config_raw = null;
  var $config_graph = null;
  var $config_page = null;

  var $rrd_fields = array();
  var $rra_base = array();
  var $rrd_step = 300;
  var $rra_add_max = true;

  var $status = 'unused';

  function rrdstat($rrdconfig, $conf_id = null) {
    // ***** init RRD stat module *****
    $this->set_def($rrdconfig, $conf_id);

    if (!is_null($this->rrd_file)) {
      if (!is_writeable($this->rrd_file)) {
        if (!file_exists($this->rrd_file)) {
          if (@touch($this->rrd_file)) { $this->create(); }
          else { trigger_error('RRD file can not be created', E_USER_WARNING); }
        }
        else {
          if (is_readable($this->rrd_file)) { $this->status = 'readonly'; }
          else { trigger_error('RRD file is not readable', E_USER_WARNING); }
        }
      }
      else {
        $this->status = 'ok';
      }
    }
  }

  function set_def($rrdconfig, $conf_id = null) {
    if (is_array($rrdconfig)) {
      // we have an array in the format we like to have
      $complete_conf =& $rrdconfig;
    }
    else {
      // we have something else (XML data?), try to generate the iinfo aray from it
      $complete_conf =& $rrdconfig;
    }

    if (!is_null($conf_id)) {
      $iinfo = isset($complete_conf[$conf_id])?$complete_conf[$conf_id]:array();
      if (isset($complete_conf['*'])) {
        $iinfo = (array)$iinfo + (array)$complete_conf['*'];
        if (isset($complete_conf['*']['graph'])) { $iinfo['graph'] = (array)$iinfo['graph'] + (array)$complete_conf['*']['graph']; }
        if (isset($complete_conf['*']['page'])) { $iinfo['page'] = (array)$iinfo['page'] + (array)$complete_conf['*']['page']; }
      }
    }
    else {
      $iinfo = $complete_conf;
    }

    if (!isset($iinfo['file'])) { return false; }

    $this->rrd_file = $iinfo['file'];
    $this->basename = (substr($this->rrd_file, -4) == '.rrd')?substr($this->rrd_file, 0, -4):$this->rrd_file;

    // fields (data sources, DS)
    //  name - DS name
    //  type - one of COUNTER, GAUGE, DERIVE, ABSOLUTE
    //  heartbeat - if no sample recieved for that time, store UNKNOWN
    //  min - U (unconstrained) or minimum value
    //  max - U (unconstrained) or maximum value
    //  update - this string will be fed into eval() for updating this field
    if (isset($iinfo['fields']) && is_array($iinfo['fields'])) {
      $this->rrd_fields = $iinfo['fields'];
    }
    else {
      $this->rrd_fields[] = array('name' => 'ds0', 'type' => 'COUNTER', 'heartbeat' => 600, 'min' => 'U', 'max' => 'U');
      $this->rrd_fields[] = array('name' => 'ds1', 'type' => 'COUNTER', 'heartbeat' => 600, 'min' => 'U', 'max' => 'U');
    }


    // MRTG-style RRD "database", see http://people.ee.ethz.ch/~oetiker/webtools/rrdtool/tut/rrdtutorial.en.html
    //
    // archives (RRAs):
    // 600 samples of 5 minutes  (2 days and 2 hours)
    // 700 samples of 30 minutes (2 days and 2 hours, plus 12.5 days)
    // 775 samples of 2 hours    (above + 50 days)
    // 797 samples of 1 day      (above + 732 days, rounded up to 797)

    $this->rrd_step = isset($iinfo['rrd_step'])?$iinfo['rrd_step']:300;

    if (isset($iinfo['rra_base']) && is_array($iinfo['rra_base'])) {
      $this->rra_base = $iinfo['rra_base'];
    }
    else {
      $this->rra_base[] = array('step' => 1, 'rows' => 600);
      $this->rra_base[] = array('step' => 6, 'rows' => 700);
      $this->rra_base[] = array('step' => 24, 'rows' => 775);
      $this->rra_base[] = array('step' => 288, 'rows' => 797);
    }

    $this->rra_add_max = isset($iinfo['rra_add_max'])?$iinfo['rra_add_max']:true;

    if (isset($iinfo['graph'])) { $this->config_graph = $iinfo['graph']; }
    if (isset($iinfo['page'])) { $this->config_page = $iinfo['page']; }
    $this->config_raw = $iinfo;
  }

  function create() {
    // create RRD file

    // compose create command
    $create_cmd = 'rrdtool create '.$this->rrd_file.' --step '.$this->rrd_step;
    foreach ($this->rrd_fields as $ds) {
      if (!isset($ds['type'])) { $ds['type'] = 'COUNTER'; }
      if (!isset($ds['heartbeat'])) { $ds['heartbeat'] = 2*$this->rrd_step; }
      if (!isset($ds['min'])) { $ds['min'] = 'U'; }
      if (!isset($ds['max'])) { $ds['max'] = 'U'; }
      $create_cmd .= ' DS:'.$ds['name'].':'.$ds['type'].':'.$ds['heartbeat'].':'.$ds['min'].':'.$ds['max'];
    }
    foreach ($this->rra_base as $rra) {
      if (!isset($rra['cf'])) { $rra['cf'] = 'AVERAGE'; }
      if (!isset($rra['xff'])) { $rra['xff'] = 0.5; }
      if (!isset($rra['step'])) { $rra['step'] = 1; }
      if (!isset($rra['rows'])) { $rra['rows'] = 600; }
      $create_cmd .= ' RRA:'.$rra['cf'].':'.$rra['xff'].':'.$rra['step'].':'.$rra['rows'];
    }
    if ($this->rra_add_max) {
      foreach ($this->rra_base as $rra) {
        if (!isset($rra['cf'])) {
          // only rows that have no CF set will be looked at here
          $rra['cf'] = 'MAX';
          if (!isset($rra['xff'])) { $rra['xff'] = 0.5; }
          if (!isset($rra['step'])) { $rra['step'] = 1; }
          if (!isset($rra['rows'])) { $rra['rows'] = 600; }
          $create_cmd .= ' RRA:'.$rra['cf'].':'.$rra['xff'].':'.$rra['step'].':'.$rra['rows'];
        }
      }
    }
    $return = `$create_cmd 2>&1`;
    if (strpos($return, 'ERROR') !== false) {
      trigger_error($this->rrd_file.' - rrd create error: '.$return, E_USER_WARNING);
    }
    else { $this->status = 'ok'; }
  }

  function update($upArray = null) {
    // feed new data into RRD
    if ($this->status != 'ok') { trigger_error('Cannot update non-writeable file', E_USER_WARNING); return 1; }
    $upvals = array();
    if (isset($this->config_raw['update'])) {
      $evalcode = $this->config_raw['update'];
      if (!is_null($evalcode)) {
        ob_start();
        eval($evalcode);
        $ret = ob_get_contents();
        if (strlen($ret)) { $upvals = explode("\n", $ret); }
        ob_end_clean();
      }
      $walkfunc = create_function('&$val,$key', '$val = is_numeric($val)?$val:"U";');
      array_walk($upvals, $walkfunc);
    }
    else {
      foreach ($this->rrd_fields as $ds) {
        if (is_array($upArray) && isset($upArray[$ds['name']])) { $val = $upArray[$ds['name']]; }
        elseif (isset($ds['update'])) {
          $val = null; $evalcode = null;
          if (substr($ds['update'], 0, 4) == 'val:') {
            $evalcode = 'print(trim('.substr($ds['update'], 4).'));';
          }
          elseif (substr($ds['update'], 0, 8) == 'snmp-if:') {
            $snmphost = 'localhost'; $snmpcomm = 'public';
            list($nix, $ifname, $valtype) = explode(':', $ds['update'], 3);
            $iflist = explode("\n", `snmpwalk -v2c -c $snmpcomm $snmphost interfaces.ifTable.ifEntry.ifDescr`);
            $ifnr = null;
            foreach ($iflist as $ifdesc) {
              if (preg_match('/ifDescr\.(\d+) = STRING: '.$ifname.'/', $ifdesc, $regs)) { $ifnr = $regs[1]; }
            }
            $oid = null;
            if ($valtype == 'in') { $oid = '1.3.6.1.2.1.2.2.1.10.'.$ifnr; }
            elseif ($valtype == 'out') { $oid = '1.3.6.1.2.1.2.2.1.16.'.$ifnr; }
            if (!is_null($ifnr) && !is_null($oid)) {
              $evalcode = 'print(trim(substr(strrchr(`snmpget -v2c -c '.$snmpcomm.' '.$snmphost.' '.$oid.'`,":"),1)));';
            }
          }
          else { $evalcode = $ds['update']; }
          if (!is_null($evalcode)) {
            ob_start();
            eval($evalcode);
            $val = ob_get_contents();
            ob_end_clean();
          }
        }
        else { $val = null; }
        $upvals[] = is_null($val)?'U':$val;
      }
    }
    $return = null;
    if (count($upvals)) {
      $update_cmd = 'rrdtool update '.$this->rrd_file.' N:'.implode(':', $upvals);
      $return = `$update_cmd 2>&1`;
    }

    if (strpos($return, 'ERROR') !== false) {
      trigger_error($this->rrd_file.' - rrd update error: '.$return, E_USER_WARNING);
      $success = false;
    }
    else { $success = true; }
  return ($return_var == 0);
  }

  function fetch($cf = 'AVERAGE', $resolution = null, $start = null, $end = null) {
    // fetch data from a RRD
    if (!in_array($this->status, array('ok','readonly'))) { trigger_error('Error: rrd status is '.$this->status, E_USER_WARNING); return false; }

    if (!in_array($cf, array('AVERAGE','MIN','MAX','LAST'))) { $cf = 'AVERAGE'; }
    if (!is_numeric($resolution)) { $resolution = $this->rrd_step; }
    if (!is_numeric($end)) { $end = $this->last_update(); }
    elseif ($end < 0) { $end += $this->last_update(); }
    $end = intval($end/$resolution)*$resolution;
    if (!is_numeric($start)) { $start = $end; }
    elseif ($start < 0) { $start += $end; }
    $start = intval($start/$resolution)*$resolution;

    $fetch_cmd = 'rrdtool fetch '.$this->rrd_file.' '.$cf.' --resolution '.$resolution.' --start '.$start.' --end '.$end;
    $return = `$fetch_cmd 2>&1`;

    if (strpos($return, 'ERROR') !== false) {
      trigger_error($this->rrd_file.' - rrd fetch error: '.$return, E_USER_WARNING);
      $fresult = false;
    }
    else {
      $fresult = array();
      $rows = explode("\n", $return);
      $fields = preg_split('/\s+/', array_shift($rows));
      if (array_shift($fields) == 'timestamp') {
        $fresult[0] = $fields;
        foreach ($rows as $row) {
          if (strlen(trim($row))) {
            $rvals = preg_split('/\s+/', $row);
            $rtime = array_shift($rvals);
            $rv_array = array();
            foreach ($rvals as $key=>$rval) {
              $rv_array[$fields[$key]] = ($rval=='nan')?null:floatval($rval);
            }
            $fresult[$rtime] = $rv_array;
          }
        }
      }
    }
  return $fresult;
  }

  function graph($timeframe = 'day', $sub = null, $extra = null) {
    // create a RRD graph
    static $gColors;
    if (!isset($gColors)) {
      $gColors = array('#00CC00','#0000FF','#000000','#FF0000','#00FF00','#FFFF00','#FF00FF','#00FFFF','#808080','#800000','#008000','#000080','#808000','#800080','#008080','#C0C0C0');
    }

    if (!in_array($this->status, array('ok','readonly'))) { trigger_error('Error: rrd status is '.$this->status, E_USER_WARNING); return false; }

    // assemble configuration
    $gconf = (array)$extra;
    if (!is_null($sub) && is_array($this->config_raw['graph.'.$sub])) {
      $gconf = $gconf + $this->config_raw['graph.'.$sub];
    }
    $gconf = $gconf + (array)$this->config_graph;

    if (isset($gconf['format']) && ($gconf['format'] == 'SVG')) {
      $format = $gconf['format']; $fmt_ext = '.svg';
    }
    elseif (isset($gconf['format']) && ($gconf['format'] == 'EPS')) {
      $format = $gconf['format']; $fmt_ext = '.eps';
    }
    elseif (isset($gconf['format']) && ($gconf['format'] == 'PDF')) {
      $format = $gconf['format']; $fmt_ext = '.pdf';
    }
    else {
      $format = 'PNG'; $fmt_ext = '.png';
    }

    if (isset($gconf['filename'])) { $fname = $gconf['filename']; }
    else { $fname = $this->basename.(is_null($sub)?'':'-%s').'-%t%f'; }
    $fname = str_replace('%s', strval($sub), $fname);
    $fname = str_replace('%t', $timeframe, $fname);
    $fname = str_replace('%f', $fmt_ext, $fname);
    if (substr($fname, -strlen($fmt_ext)) != $fmt_ext) { $fname .= $fmt_ext; }
    if (isset($gconf['path'])) { $fname = $gconf['path'].'/'.$fname; }
    $fname = str_replace('//', '/', $fname);

    $graphrows = array(); $gC = 0;
    $gDefs = ''; $gGraphs = ''; $addSpecial = '';

    if ($timeframe == 'day') {
      $duration = isset($gconf['duration'])?$gconf['duration']:30*3600; // 30 hours
      $slice = isset($gconf['slice'])?$gconf['slice']:300; // 5 minutes
      // vertical lines at day borders
      $addSpecial .= ' VRULE:'.strtotime(date('Y-m-d')).'#FF0000';
      $addSpecial .= ' VRULE:'.strtotime(date('Y-m-d').' -1 day').'#FF0000';
      if (!isset($gconf['grid_x'])) { $gconf['grid_x'] = 'HOUR:1:HOUR:6:HOUR:2:0:%-H'; }
    }
    elseif ($timeframe == 'week') {
      $duration = isset($gconf['duration'])?$gconf['duration']:8*86400; // 8 days
      $slice = isset($gconf['slice'])?$gconf['slice']:1800; // 30 minutes
      // vertical lines at week borders
      $addSpecial .= ' VRULE:'.strtotime(date('Y-m-d').' '.(-date('w')+1).' day').'#FF0000';
      $addSpecial .= ' VRULE:'.strtotime(date('Y-m-d').' '.(-date('w')-6).' day').'#FF0000';
    }
    elseif ($timeframe == 'month') {
      $duration = isset($gconf['duration'])?$gconf['duration']:36*86400; // 36 days
      $slice = isset($gconf['slice'])?$gconf['slice']:7200; // 2 hours
      // vertical lines at month borders
      $addSpecial .= ' VRULE:'.strtotime(date('Y-m-01')).'#FF0000';
      $addSpecial .= ' VRULE:'.strtotime(date('Y-m-01').' -1 month').'#FF0000';
    }
    elseif ($timeframe == 'year') {
      $duration = isset($gconf['duration'])?$gconf['duration']:396*86400; // 365+31 days
      $slice = isset($gconf['slice'])?$gconf['slice']:86400; // 1 day
      // vertical lines at month borders
      $addSpecial .= ' VRULE:'.strtotime(date('Y-01-01 12:00:00')).'#FF0000';
      $addSpecial .= ' VRULE:'.strtotime(date('Y-01-01 12:00:00').' -1 year').'#FF0000';
    }
    else {
      $duration = isset($gconf['duration'])?$gconf['duration']:$this->rrd_step*500; // 500 steps
      $slice = isset($gconf['slice'])?$gconf['slice']:$this->rrd_step; // whatever our step is
    }

    if (isset($gconf['rows']) && count($gconf['rows'])) {
      foreach ($gconf['rows'] as $erow) {
        if (isset($erow['name']) && strlen($erow['name'])) {
          if (!isset($erow['scale']) && isset($gconf['scale'])) { $erow['scale'] = $gconf['scale']; }
          $grow = array();
          $grow['dType'] = isset($erow['dType'])?$erow['dType']:'DEF';
          $grow['name'] = $erow['name'].(isset($erow['scale'])?'_tmp':'');
          if ($grow['dType'] == 'DEF') {
            $grow['dsname'] = isset($erow['dsname'])?$erow['dsname']:$erow['name'];
            $grow['cf'] = isset($erow['cf'])?$erow['cf']:'AVERAGE';
          }
          else {
            $grow['rpn_expr'] = isset($erow['rpn_expr'])?$erow['rpn_expr']:'0';
          }
          if (isset($erow['scale'])) {
            $graphrows[] = $grow;
            $grow = array();
            $grow['dType'] = 'CDEF';
            $grow['name'] = $erow['name'];
            $grow['rpn_expr'] = $erow['name'].'_tmp,'.$erow['scale'].',*';
          }
          $grow['gType'] = isset($erow['gType'])?$erow['gType']:'LINE1';
          $grow['color'] = isset($erow['color'])?$erow['color']:$gColors[$gC++];
          if ($gC >= count($gColors)) { $gC = 0; }
          if (isset($erow['legend'])) {
            $grow['legend'] = $erow['legend'];
            if (!isset($gconf['show_legend'])) { $gconf['show_legend'] = true; }
          }
          if (isset($erow['stack'])) { $grow['stack'] = ($erow['stack'] == true); }
          $graphrows[] = $grow;
        }
      }
    }
    else {
      foreach ($this->rrd_fields as $key=>$ds) {
        $grow = array();
        $grow['dType'] = 'DEF';
        $grow['name'] = $ds['name'].(isset($gconf['scale'])?'_tmp':'');
        $grow['dsname'] = $ds['name'];
        $grow['cf'] = 'AVERAGE';
        if (isset($gconf['scale'])) {
          $graphrows[] = $grow;
          $grow = array();
          $grow['dType'] = 'CDEF';
          $grow['name'] = $ds['name'];
          $grow['rpn_expr'] = $ds['name'].'_tmp,'.$gconf['scale'].',*';
        }
        $grow['gType'] = ((count($this->rrd_fields)==2) && ($key==0))?'AREA':'LINE1';
        $grow['color'] = $gColors[$gC++]; if ($gC >= count($gColors)) { $gC = 0; }
        $graphrows[] = $grow;
      }
    }

    if (isset($gconf['special']) && count($gconf['special'])) {
      foreach ($gconf['special'] as $crow) {
        $srow = array();
        $srow['sType'] = isset($crow['sType'])?$crow['sType']:'COMMENT';
        if ($grow['sType'] != 'COMMENT') {
          // XXX: use line below and remove cf var once we have rrdtol 1.2
          // $srow['name'] = $crow['name'].(isset($crow['cf'])?'_'.$crow['cf']:'');
          $srow['name'] = $crow['name'];
          $srow['cf'] = isset($crow['cf'])?$crow['cf']:'AVERAGE';
          if (isset($crow['cf'])) {
            // XXX: use line below once we have rrdtol 1.2
            // $graphrows[] = array('dType'=>'VDEF', 'name'=>$srow['name'].'_'.$crow['cf'], 'rpn_expr'=>$srow['name'].','.$crow['cf']);
          }
          elseif (isset($crow['rpn_expr'])) {
            // XXX: does only work with rrdtool 1.2
            $graphrows[] = array('dType'=>'VDEF', 'name'=>$srow['name'], 'rpn_expr'=>$crow['rpn_expr']);
          }
        }
        $srow['text'] = isset($crow['text'])?$crow['text']:'';
        $specialrows[] = $srow;
      }
    }
    else {
      foreach ($graphrows as $grow) {
        if (isset($grow['gType']) && strlen($grow['gType'])) {
          $textprefix = isset($grow['legend'])?$grow['legend']:$grow['name'];
          // XXX: use lines below once we have rrdtol 1.2
          // $graphrows[] = array('dType'=>'VDEF', 'name'=>$grow['name'].'_last', 'rpn_expr'=>$grow['name'].',LAST');
          // $specialrows[] = array('sType'=>'PRINT', 'name'=>$grow['name'].'_last', 'text'=>'%3.2lf%s');
          $specialrows[] = array('sType'=>'PRINT', 'name'=>$grow['name'], 'cf'=>'MAX', 'text'=>$textprefix.'|Maximum|%.2lf%s');
          $specialrows[] = array('sType'=>'PRINT', 'name'=>$grow['name'], 'cf'=>'AVERAGE', 'text'=>$textprefix.'|Average|%.2lf%s');
          $specialrows[] = array('sType'=>'PRINT', 'name'=>$grow['name'], 'cf'=>'LAST', 'text'=>$textprefix.'|Current|%.2lf%s');
        }
      }
    }

    $endtime = isset($gconf['time_end'])?$gconf['time_end']:(is_numeric($this->last_update())?$this->last_update():time());
    $gOpts = ' --start '.($endtime-$duration).' --end '.$endtime.' --step '.$slice;
    if (isset($gconf['label_top'])) { $gOpts .= ' --title '.$this->text_quote($gconf['label_top']); }
    if (isset($gconf['label_y'])) { $gOpts .= ' --vertical-label '.$this->text_quote($gconf['label_y']); }
    if (isset($gconf['width'])) { $gOpts .= ' --width '.$gconf['width']; }
    if (isset($gconf['height'])) { $gOpts .= ' --height '.$gconf['height'];
      if (($gconf['height'] <= 32) && isset($gconf['thumb']) && ($gconf['thumb'])) { $gOpts .= ' --only-graph'; }
    }
    if (!isset($gconf['show_legend']) || (!$gconf['show_legend'])) { $gOpts .= ' --no-legend'; }
    if (isset($gconf['min_y'])) { $gOpts .= ' --lower-limit '.$gconf['min_y']; }
    if (isset($gconf['max_y'])) { $gOpts .= ' --upper-limit '.$gconf['max_y']; }
    if (isset($gconf['fix_scale_y']) && $gconf['fix_scale_y']) { $gOpts .= ' --rigid'; }
    if (isset($gconf['grid_x'])) { $gOpts .= ' --x-grid '.$gconf['grid_x']; }
    if (isset($gconf['grid_y'])) { $gOpts .= ' --y-grid '.$gconf['grid_y']; }
    if (isset($gconf['units_exponent'])) { $gOpts .= ' --units-exponent '.$gconf['units_exponent']; }
    if (isset($gconf['units_length'])) { $gOpts .= ' --units-length '.$gconf['units_length']; }
    if (!isset($gconf['force_recreate']) || (!$gconf['force_recreate'])) { $gOpts .= ' --lazy'; }
    if (isset($gconf['force_color']) && is_array($gconf['force_color'])) {
      foreach ($gconf['force_color'] as $ctag=>$cval) { $gOpts .= ' --color '.$ctag.$cval; }
    }
    if (isset($gconf['force_font']) && is_array($gconf['force_font'])) {
      foreach ($gconf['force_font'] as $ctag=>$cval) { $gOpts .= ' --font '.$ctag.$cval; }
    }
    if (isset($gconf['units_binary']) && $gconf['units_binary']) { $gOpts .= ' --base 1024'; }

    foreach ($graphrows as $grow) {
      if (isset($grow['dType']) && strlen($grow['dType'])) {
        $gDefs .= ' '.$grow['dType'].':'.$grow['name'].'=';
        $gDefs .= ($grow['dType']=='DEF')?$this->rrd_file.':'.$grow['dsname'].':'.$grow['cf']:$grow['rpn_expr'];
      }
      if (isset($grow['gType']) && strlen($grow['gType'])) {
        // XXX: change from STACK type to STACK flag once we have rrdtool 1.2
        if (isset($grow['stack']) && $grow['stack']) { $grow['gType'] = 'STACK'; }
        $gGraphs .= ' '.$grow['gType'].':'.$grow['name'].$grow['color'];
        if (isset($grow['legend'])) { $gGraphs .= ':'.$this->text_quote($grow['legend']); }
        // XXX: remove above STACK if-command and uncomment the one below once we have rrdtool 1.2
        //if (isset($grow['stack']) && $grow['stack']) { $gGraphs .= ':STACK'; }
      }
    }

    foreach ($specialrows as $srow) {
      $addSpecial .= ' '.$srow['sType'];
      // XXX: eliminate cf once we have rrdtool 1.2
      // $addSpecial .= ($grow['sType']!='COMMENT')?':'.$grow['name']:'');
      $addSpecial .= (($srow['sType']!='COMMENT')?':'.$srow['name'].':'.$srow['cf']:'');
      $addSpecial .= ':'.$this->text_quote($srow['text']);
    }

    $graph_cmd = 'rrdtool graph '.str_replace('*', '\*', $fname.$gOpts.$gDefs.$gGraphs.$addSpecial);
    $return = `$graph_cmd 2>&1`;

    if (strpos($return, 'ERROR') !== false) {
      trigger_error($this->rrd_file.' - rrd graph error: '.$return, E_USER_WARNING);
      $return = $graph_cmd."\n\n".$return;
    }
    $return = 'file:'.$fname."\n".$return;
  return $return;
  }

  function simple_html($sub = null, $page_extras = null, $graph_extras = null) {
    // create a simple (MRTG-like) HTML page and return it in a string

    // assemble configuration
    $pconf = (array)$page_extras;
    if (!is_null($sub) && is_array($this->config_raw['page.'.$sub])) {
      $pconf = $pconf + $this->config_raw['page.'.$sub];
    }
    $pconf = $pconf + (array)$this->config_page;

    $ptitle = isset($pconf['title_page'])?$pconf['title_page']:$this->basename.' - RRD statistics';
    $gtitle = array();
    $gtitle['day'] = isset($pconf['title_day'])?$pconf['title_day']:'Day overview (scaling 5 minutes)';
    $gtitle['week'] = isset($pconf['title_week'])?$pconf['title_week']:'Week overview (scaling 30 minutes)';
    $gtitle['month'] = isset($pconf['title_month'])?$pconf['title_month']:'Month overview (scaling 2 hours)';
    $gtitle['year'] = isset($pconf['title_year'])?$pconf['title_year']:'Year overview (scaling 1 day)';

    $out = '<html><head>';
    $out .= '<title>'.$ptitle.'</title>';
    $out .= '<style>';
    if (isset($pconf['style_base'])) { $out .= $pconf['style_base']; }
    else {
      $out .= 'h1 { font-weight: bold; font-size: 1.5em; }';
      $out .= 'h2 { font-weight: bold; font-size: 1em; }';
      $out .= '.gdata, .gvar, .ginfo { font-size: 0.75em; margin: 0.5em 0; }';
      $out .= 'table.gdata { border: 1px solid gray; border-collapse: collapse; }';
      $out .= 'table.gdata td, table.gdata th { border: 1px solid gray; padding: 0.1em 0.2em; }';
      $out .= '.footer { font-size: 0.75em; margin: 0.5em 0; }';
    }
    if (isset($pconf['style'])) { $out .= $pconf['style']; }
    $out .= '</style>';
    $out .= '</head>';
    $out .= '<body>';

    $out .= '<h1>'.$ptitle.'</h1>';
    if (!isset($pconf['show_update']) || $pconf['show_update']) {
      $out .= '<p class="last_up">Last Update: '.(is_null($this->last_update())?'unknown':date('Y-m-d H:i:s', $this->last_update())).'</p>';
    }

    if (in_array($this->status, array('ok','readonly'))) {
      $g_sub = isset($pconf['graph_sub'])?$pconf['graph_sub']:null;
      foreach (array('day','week','month','year') as $tframe) {
        $ret = $this->graph($tframe, $g_sub, $graph_extras);
        if (strpos($ret, "\n\n") !== false) { $graph_cmd = substr($ret, 0, strpos($ret, "\n\n")); $ret = substr($ret, strpos($ret, "\n\n")+2); }
        else { $graph_cmd = null; }
        $grout = explode("\n",$ret);
        $gfilename = null;
        $gmeta = array();
        foreach ($grout as $gline) {
          if (preg_match('/^file:(.+)$/', $gline, $regs)) {
            $gfilename = $regs[1];
          }
          elseif (preg_match('/^(\d+)x(\d+)$/', $gline, $regs)) {
            $gmeta['width'] = $regs[1]; $gmeta['height'] = $regs[2];
          }
          elseif (preg_match('/^([^\|]+)\|([^|]+)\|([^\|]*)$/', $gline, $regs)) {
            $gmeta['data'][$regs[1]][$regs[2]] = $regs[3];
          }
          elseif (preg_match('/^([^\|]+)\|([^\|]*)$/', $gline, $regs)) {
            $gmeta['var'][$regs[1]] = $regs[2];
          }
          elseif (strlen(trim($gline))) {
            $gmeta['info'][] = $gline;
          }
        }
        if (is_null($gfilename)) { $gfilename = $this->basename.(!is_null($g_sub)?'-'.$g_sub:'').'-'.$tframe.'.png'; }
        if (isset($pconf['graph_url'])) {
          $gURL = $pconf['graph_url'];
          $fname = str_replace('%f', basename($gfilename), $gURL);
          $fname = str_replace('%p', $gfilename, $gURL);
          if (substr($gURL, -1) == '/') { $gURL .= $gfilename; }
        }
        else {
          $gURL = $gfilename;
        }
        $out .= '<div class="'.$tframe.'">';
//         $out .= '<p>'.nl2br($ret).'</p>';
        $out .= '<h2>'.$gtitle[$tframe].'</h2>';
        $out .= '<img src="'.$gURL.'"';
        $out .= ' alt="'.$this->basename.(!is_null($g_sub)?' - '.$g_sub:'').' - '.$tframe.'" class="rrdgraph"';
        $out .= ' style="width:'.$gmeta['width'].'px;height:'.$gmeta['height'].'px;">';
        if (isset($gmeta['data']) && count($gmeta['data'])) {
          $out .= '<table class="gdata">';
          foreach ($gmeta['data'] as $field=>$gdata) {
            $out .= '<tr><th>'.$field.'</th>';
            foreach ($gdata as $gkey=>$gval) {
              $out .= '<td><span class="gkey">'.$gkey.': </span>'.$gval.'</td>';
            }
            $out .= '</tr>';
          }
          $out .= '</table>';
        }
        if (isset($gmeta['var']) && count($gmeta['var'])) {
          foreach ($gmeta['var'] as $gkey=>$gval) {
            $out .= '<p class="gvar"><span class="gkey">'.$gkey.': </span>'.$gval.'</p>';
          }
        }
        if (isset($gmeta['info']) && count($gmeta['info'])) {
          foreach ($gmeta['info'] as $gval) {
            $out .= '<p class="ginfo">'.$gval.'</p>';
          }
        }
      }
    }
    else {
      $out .= 'RRD error: status is "'.$this->status.'"';
    }
    $out .= '</div>';

    $out .= '<p class="footer">';
    $out .= 'Statistics created by <a href="http://people.ee.ethz.ch/~oetiker/webtools/rrdtool/">RRDtool</a>';
    $out .= ' using a library created by <a href="http://www.kairo.at/">KaiRo.at</a>.';
    $out .= '</p>';

    $out .= '</body></html>';
  return $out;
  }

  function last_update() {
    // fetch time of last update in this RRD file
    static $last_update;
    if (!isset($last_update) && in_array($this->status, array('ok','readonly'))) {
      $last_cmd = 'rrdtool last '.$this->rrd_file;
      $return = trim(`$last_cmd 2>&1`);
      $last_update = is_numeric($return)?$return:null;
    }
  return isset($last_update)?$last_update:null;
  }

  function text_quote($text) { return '"'.str_replace('"', '\"', str_replace(':', '\:', $text)).'"'; }
}
?>