<?php

  define('DEBUG',0);
  define('SPACE',3.5);
  define('YOFFSET',179);
  define('XOFFSET', 40);
  define('CALXOFFSET', 9.36);
  define('FONT', 3);
  define('BARWIDTH', 30.64);
  //this is the server we want to draw for(full path)
  $serv = $_REQUEST['server'];
  //this allows us to use this code to draw the current,last5 and last15(1,2,3) 
  //$resolution = $_REQUEST['resolution'];
  //check that hte request is a number, if it isn't then set it to 0
  //if( is_numeric($resolution) === FALSE)
  $resolution = 2;
  //check to see if someone passed in a request for a specific month
  if( isset($_REQUEST['month']) && $_REQUEST['month'] != '' && is_numeric($_REQUEST['month']) && $_REQUEST['month'] >= 1 &&  $_REQUEST['month'] <= 12 ){
    $month = $_REQUEST['month'];
  }else{  //if whatever the passed failed the above get the current month so that we can open the files.
    $month = date ('n');
  }
  //check to see if someone passed in a request for a specific year
  if( isset($_REQUEST['year']) && $_REQUEST['year'] != '' && is_numeric($_REQUEST['year']) && $_REQUEST['year'] >= 2007 &&  $_REQUEST['year'] <= 3000 ){
    $year = $_REQUEST['year'];
  }else{  //if whatever the passed failed the above get the current year so that we can open the files.
    $year = date ('Y');
  }
  //get the Current month 3 letter short form
  $month_name = date( 'M', mktime( 0,0,0,$month,1,$year));
  
  //break down the request string so that the name can be extracted
  $name = explode('/',$serv);
  //get the number of days in this month
  $numberofdays = date('t',mktime(0,0,0,$month,1,$year));
  
  header("Content-type: image/png");
  $im = imagecreate(1000, 200);
    
  //now compute the y offset based on the font height
  $fonthieght = (imagefontheight( FONT ))/2;
  $fontwidth = imagefontwidth( FONT );
  //Allocate colors 
  $white  = imagecolorallocate($im, 255, 255, 255);
  $red = imagecolorallocate($im, 240, 70, 70);
  $blue = imagecolorallocate($im, 70, 70, 240);
  $green = imagecolorallocate($im, 70, 240, 70);
  $black = imagecolorallocate($im, 0, 0, 0);
  //  Background 
  imagefilledrectangle($im, 0, 0, imagesx($im), imagesy($im), $white);
  //  Title 
  $title = "Load for: " . end($name) . " durring " . $month_name . " " . $year;
  //compute the middle of the image(i know it should be 'static')
  $title_x = (imagesx($im)/2 - 40) - (strlen($title)) ;
  //now compute the y offset based on the font height
  $title_y =  ($fonthieght - 4);
  imagestring($im, FONT, $title_x, $title_y, $title, $black);
  $index = 0;
  $maxload= 0.1;
  $minload= 10000;
  
  //check tha thte request month exists
  $checkdir = $serv ."/" . $year ."/" . $month_name;	
  if( is_dir( $checkdir ) == true) {
  	if( DEBUG == 1) {
  	  $msg="Dir exists!";
  	  imagestring($im, FONT, 50, 20, $msg, $black);	
  	}
    //start the day processing loop
    for( $days = 1; $days <= $numberofdays; $days++) {
      //  open the data file for today.
      $day_code = date( 'd', mktime( 0,0,0,$month,$days,$year));
      $data = @file( $serv ."/" . $year . "/" . $month_name . "/loadavgfor." . $day_code);
      if ( $data !== false ){
        $count = 0;    
        $total = 0;  
        foreach( $data as $line ) {
          list( $load_data[$index][0],$load_data[$index][1],$load_data[$index][2],$load_data[$index][3]) = explode(',',rtrim($line));
          $total = $total+ $load_data[$index][$resolution]; 
          $count=$count+1;
        }
        //compute the average for this day
        $dayavg[$days] = $total/$count;   
      } else {
      	$dayavg[$days] = 0;
      }
      $maxload =  ($dayavg[$days] < $maxload) ? $maxload : $dayavg[$days];
      if ( $dayavg[$days] != 0 )
        $minload =  ($dayavg[$days] > $minload) ? $minload : $dayavg[$days];
    }
    //clean up max vaule
    $maxload = round( $maxload, 2);
    $minload = round( $minload, 2);
    $mult = (YOFFSET - 15)/$maxload;
        
    $index = 1;
    for( $days = 1; $days <= $numberofdays; $days++) {
      //find out wher the hell this item goes
      $datax =  CALXOFFSET + $days * BARWIDTH;
      $load_y = YOFFSET - ( $dayavg[$days] * $mult);
      imagefilledrectangle($im, $datax, $load_y, $datax+BARWIDTH, YOFFSET, $blue);
      $textx = $datax + (15-$fontwidth);
      imagestring($im, FONT, $textx, 185, $days, $black);
      if( DEBUG == 1 ){
        imagestring($im, FONT, $datax, $minutes, $datax, $black);    
      }        
    }
    //now work out where the end of the graph will be
    $title_x = XOFFSET + ( $numberofdays ) * BARWIDTH;
    //now a line to mark the right side end
    imageline($im, $title_x, 10, $title_x, 180, $black);
    //draw a base line to seperate the lower text
    imageline($im, 40, 180, $title_x, 180, $black);
    //display the max value
    $max_y = (YOFFSET - ($maxload * $mult )) - $fonthieght;
    imagestring($im, FONT, 0, $max_y, $maxload, $red);
    //liine
    $max_y = $max_y + $fonthieght;
    imageline($im, 40, $max_y, $title_x,$max_y, $black);
    //the min value
    $min_y = (YOFFSET - ($minload * $mult )) - $fonthieght;
    imagestring($im, FONT, 0, $min_y, $minload, $green);
    $min_y = $min_y + $fonthieght;
    imageline($im, 40, $min_y, $title_x,$min_y, $black);
    //now one to seperate the scale
    imageline($im, XOFFSET-1, 10, XOFFSET-1, 180, $black);
    //draw some ticks for the load scale
    $loadscale = $maxload /5;
    for( $mark = 1; $mark <= 4; $mark++) {
      $scale =YOFFSET -( $loadscale * $mult * $mark);
      if ( ( $scale > ($max_y - ($fonthieght*2)) ) && ( $scale < ($max_y + ($fonthieght*2)) ) ){
      	continue;
      }
      else if ( ( $scale > ($min_y - ($fonthieght*2)) ) && ( $scale < ($min_y + ($fonthieght*2)) ) ){
      	continue;
      }
      imageline($im, 35, $scale, 990, $scale, $black);
      imagestring($im, FONT, 0, ($scale- $fonthieght), round( ($loadscale * $mark), 2), $black);
    }
    
    // Display image 
    imagepng($im);
    // Release allocated resources 
    imagedestroy($im);
  } else {
  	//  Background 
    imagefilledrectangle($im, 0, 0, imagesx($im), imagesy($im), $white);
    //  Title 
    $title = "Unable to find the requested data for: " . $month_name . " " . $year;
    //compute the middle of the image(i know it should be 'static')
    $title_x = (imagesx($im)/2 ) - (strlen($title)+XOFFSET) ;
    //now compute the y offset based on the font height
    $title_y =  (imagesy($im)/2 ) - ($fonthieght - 4);
    imagestring($im, FONT, $title_x, $title_y, $title, $red);
    // Display image 
    imagepng($im);
    // Release allocated resources 
    imagedestroy($im);
  }
?>