#!/usr/bin/perl
#
# $Id: graph.png,v 1.12 2002/05/16 01:31:23 minaeibi Exp $
#
# Copyright Michigan State University Board of Trustees
#
# This file is part of the LearningOnline Network with CAPA (LON-CAPA).
#
# LON-CAPA is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# LON-CAPA is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with LON-CAPA; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#
# /home/httpd/cgi-bin/graph.gif
#
# http://www.lon-capa.org/
#
# The LearningOnline Network with CAPA
# Behrouz Minaei
# YEAR=2001
# 9/13/01, 9/25/01, 10/6/01, 10/9/01, 12/25/01
# YEAR=2002
# 2/1/02, 5/13/02, 
# A CGI script that dynamically outputs a graphical chart for lonstatistics.
# 
#### 

use strict;
use GD::Graph::bars;
use GD::Graph::colour;
use GD::Graph::Data;

$|=1;   # Autoflush after each print/write
my ($Titr,$xlab,$ylab,$Max,$PNo,$data1,$data2)=split(/&/,$ENV{'QUERY_STRING'});

my @data11=split(/\,/,$data1);
my @data12=split(/\,/,$data2);

my @xlabels;
for (my $nIdx=0; $nIdx<$PNo; $nIdx++ ) {
    $xlabels[$nIdx]=$nIdx+1;
} 

#my $bg = (defined(@data2)) ? 'lorange' : 'white';

my @data =(\@xlabels,\@data11,\@data12);

my $Range1;
my $Range2;

if ($xlab=~/^Concepts$/){
    $Range1=270;
    $Range2=200;
} else {
    if ( $PNo > 10 ) {
	$Range1 = 20*$PNo;
    } else { 
        $Range1 = 250+30*$PNo; 
    }
    $Range2=200; 
}


my $MyGraph = GD::Graph::bars->new($Range1,$Range2);

$MyGraph->set( 
 #   x_label         => $xlab,
    y_label         => $ylab,
    long_ticks      => 1,
    tick_length     => 0,
    x_ticks         => 0,
#    title           => 'LON-CAPA Option Response Problem:'.$cid,
    title           => $Titr,
    y_max_value     => $Max,
#    y_tick_number   => $ytic,
    y_label_skip    => 1,   

    dclrs           => [ qw( green dgreen lyellow lpurple cyan lorange)],
    
    bar_spacing     => 10,
    cumulate        => 2,
    zero_axis        => 1,

#    legend_placement    => 'RT',

    fgclr               => 'black',
    boxclr              => 'lorange',
    accentclr           => 'dblue',
    valuesclr           => '#ffff77',
    l_margin            => 10,
    b_margin            => 10,
    r_margin            => 10,
    t_margin            => 10,

    transparent     => 0,
) or warn $MyGraph->error; 
#if ($xlab=~/^Concepts$/){
#    $MyGraph->set_legend( 'Correct Answers', 'Incorrect Answers');
#}


# Tell the server we are sending a gif graphic
print <<END;
Content-type: image/gif

END

#$MyGraph->set_y_label_font('/home/httpd/cgi-bin/cetus.ttf', 16);
#$MyGraph->set_x_label_font('/home/httpd/cgi-bin/cetus.ttf', 16);
#$MyGraph->set_y_axis_font('/home/httpd/cgi-bin/cetus.ttf', 12);
#$MyGraph->set_x_axis_font('/home/httpd/cgi-bin/cetus.ttf', 12);
#$MyGraph->set_title_font('/home/httpd/cgi-bin/cetus.ttf', 18);
#$MyGraph->set_legend_font('/home/httpd/cgi-bin/cetus.ttf', 10);
#$MyGraph->set_values_font('/home/httpd/cgi-bin/cetus.ttf', 10);


my $BinaryData=$MyGraph->plot(\@data)->png;
undef $MyGraph;
binmode(STDOUT);
open IMG,"|pngtopnm|ppmtogif 2>/dev/null"; # convert into a gif image
print IMG $BinaryData; # output image
$|=1; # be sure to flush before closing
close IMG;