<?php

  /********************************
   * Name: get_hour_offset
   * Function: since the time via update on the nodes is not 24hour it needs to be adjusted 
   * for processing in the following special cases: if it's morning and the hour is 12 then the
   * the result needs to be 0.  Also if it's afternoon/evening and the hour is NOT 12, then the result 
   * needs to be +12.
   * 
   * I/O: takes the current hour(from the data not local time) and the minutes(which has am/pm stuck on)
   * returns the modifier(0(default(AM)), -12(12am) or +12(!12PM))
   * 
   * 
   */
  function get_hour_offset( $hour, $indicator ){
  	//is it 12 am?
  	if( ( $hour == 12) && ( preg_match('/am/i',$indicator) == 1) ){
  	  return -12; 
  	}
  	//how about some time after lunch?
  	else if( ( $hour != 12) && ( preg_match('/pm/i',$indicator) == 1) ){
  	  return 12;
  	} else {
  	  return 0;
  	}
  }
  
  define('DEBUG',0);
  define('SPACE',3.5);
  define('YOFFSET',179);
  define('XOFFSET', 40);
  define('FONT', 3);
  define('BARWIDTH', 3.29);
  //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)
  $resolution = 2;
  //check to see if someone passed in a request for a specific day
  if( isset($_REQUEST['day']) && $_REQUEST['day'] != '' && is_numeric($_REQUEST['day']) && $_REQUEST['day'] >= 0 &&  $_REQUEST['day'] <= 31 ){
    $today = $_REQUEST['day'];
  }else{ //if whatever the passed failed the above get the current day so that we can open the files.
    $today = date ( 'd' );
  }
  //check to see if someone passed in a request for a specific month
  if( isset($_REQUEST['month']) && $_REQUEST['month'] != '' && is_numeric($_REQUEST['month']) && $_REQUEST['month'] >= 0 &&  $_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,$today,$year));
  
  //break down the request string so that the name can be extracted
  $name = explode('/',$serv);
  //open the data file for today.
  $data = @file( $serv . "/" . $year . "/" . $month_name . "/loadavgfor." . $today);
  #echo "walla: " . $data;
  if ( $data !== false ){
  	//set the start point in so that ther 
    $x = XOFFSET+1;
    header("Content-type: image/png");
    $im = imagecreate(1000, 200);
    
    //now compute the y offset based on the font height
    $fonthieght = (imagefontheight( FONT ))/2;
    
    //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) . " on " . $month_name . " " . $today . " " . $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;
    
    foreach( $data as $line ) {
      //list( $time,$current,$lastfive,$lastonefive) = explode(',',$line);
      list( $load_data[$index][0],$load_data[$index][1],$load_data[$index][2],$load_data[$index][3]) = explode(',',rtrim($line));
      $maxload =  ($load_data[$index][$resolution] < $maxload) ? $maxload : $load_data[$index][$resolution];
      $minload =  ($load_data[$index][$resolution] > $minload) ? $minload : $load_data[$index][$resolution];
      $index=$index+1;
    }// Draw time
    
    $title_y =  190 - $fonthieght ;
    $Start = $load_data[0][0];
    $Stop = $load_data[$index-1][0];
    //this is the 'start'
    list($hour,$minutes) = explode(':',$Start);
    $title_x = XOFFSET + ((($hour+get_hour_offset($hour,$minutes)) * 12) + ( $minutes/5)) * BARWIDTH;
    imagestring($im, FONT, $title_x, $title_y ,$Start,$black);
       
    //this is the 'stop'
    list($hour,$minutes) = explode(':',$Stop);
    $title_x = XOFFSET + ((($hour+get_hour_offset($hour,$minutes)) * 12) + ( $minutes/5)) * BARWIDTH;
    imagestring($im, FONT, $title_x, $title_y ,$Stop,$black);
    //now one to seperate the scale
    imageline($im, XOFFSET-1, 10, XOFFSET-1, 180, $black);
    //now work out where the end of the graph will be
    $title_x = XOFFSET + ( 24 * 12 ) * BARWIDTH;
    //now a line to mark the right side end
    imageline($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);
    
    //now ticks to mark each hour
    for( $loop = 1; $loop <=24; $loop++){
     $datax = XOFFSET + ( $loop * 12 ) * BARWIDTH;
     imageline($im, $datax, 175, $datax, 185, $black);
     //mark every 3 hours
     if ( ( $loop % 3 ) == 0 )
       if( $loop > 12)
        imagestring($im, FONT, $datax, (190-$fonthieght), $loop-12, $black);
       else
        imagestring($im, FONT, $datax, (190-$fonthieght), $loop, $black);
    }
    
    //change the processing based on resolution( 0 is current, 1 is last five and 2 is last 15)
    if( $resolution == 1 ){
      $color = $green;
    }else if( $resolution == 2 ){
      $color = $blue;
    }else if( $resolution == 3 ){
      $color = $red;
    }
    //compute the offset mult(dynamically adjust the hieghts of the bars)
    $mult = (YOFFSET - 15)/$maxload;
    $index = 0;
    foreach( $load_data as $load){
      //find out where the hell this item goes
      //first we explode the hours and minutes out of the time stamp
      // the hours * 12 * BARWIDTH are where this bar should go.
      //but the fine tune is all that + ((minutes/5) * BARWIDTH
      //catch is minute values that fall out of mod 5 will get in the way so we will 
      //use them to control wether or not we process this value
      list($hour,$minutes) = explode(':',$load[0]);
      if ( ( $minutes % 5 ) == 0) {
      	$datax = XOFFSET + ((($hour+get_hour_offset($hour,$minutes)) * 12) + ( $minutes/5) ) * BARWIDTH;
      	//testing local $datax = (XOFFSET + 1) + ( ( $hour * 12 ) + ( $minutes/5) ) * BARWIDTH;
        $load_y = YOFFSET - ( $load[$resolution] * $mult);
        imagefilledrectangle($im, $datax, $load_y, $datax+BARWIDTH, YOFFSET, $color);
        if( DEBUG == 1 )
          imagestring($im, FONT, $datax, $minutes, get_hour_offset($hour,$minutes), $black);    
      }        
    }
    //display the max value
    $max_y = (YOFFSET - ($maxload * $mult )) - $fonthieght;
    imagestring($im, FONT, 0, $max_y, $maxload, $red);
    //now for a marker line
    $max_y = $max_y + $fonthieght;
    imageline($im, 40, $max_y, $datax,$max_y, $black);
    //now the min value
    $min_y = (YOFFSET - ($minload * $mult )) - $fonthieght;
    imagestring($im, FONT, 0, $min_y, $minload, $green);//another marker line
    $min_y = $min_y + $fonthieght;
    imageline($im, 40, $min_y, $datax, $min_y, $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, $datax, $scale, $black);
      imagestring($im, FONT, 0, ($scale- $fonthieght), round( ($loadscale * $mark), 2), $black);
    }
    
    // Display image 
    imagepng($im);
    // Release allocated resources 
    imagedestroy($im);
  } else {
  	 header("Content-type: image/png");
    $im = imagecreate(800, 200);
    
    //now compute the y offset based on the font height
    $fonthieght = (imagefontheight( FONT ))/2;
    
    //Allocate colors 
    $white  = imagecolorallocate($im, 255, 255, 255);
    $red = imagecolorallocate($im, 240, 70, 70);
    //  Background 
    imagefilledrectangle($im, 0, 0, imagesx($im), imagesy($im), $white);
    //  Title 
    $title = "Unable to find the requested data for: " . $month_name . " " . $today . " " . $year;
    //compute the middle of the image(i know it should be 'static')
    $title_x = (imagesx($im)/2 ) - (strlen($title)) ;
    //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);
  }
?>