# The LearningOnline Network with CAPA
# Dynamic plot
#
# $Id: lonplot.pm,v 1.8 2001/12/19 19:22:52 matthew 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/html/adm/gpl.txt
#
# http://www.lon-capa.org/
#
# 12/15/01 Matthew
# 12/18 Matthew
package Apache::lonplot;
use strict;
use Apache::response;
use Apache::lonxml;
use Digest::MD5  qw(md5 md5_hex md5_base64);

sub BEGIN {
  &Apache::lonxml::register('Apache::lonplot',('plot'));
}

##
## Tests used in checking the validitity of input
##
my $int_test       = sub {$_[0]=~/^\d+$/};
my $real_test      = sub {$_[0]=~/^[+-]?\d*\.?\d*$/};
my $color_test     = sub {$_[0]=~/^x[\da-f]{6}$/};
my $onoff_test     = sub {$_[0]=~/^(on|off)$/};
my $key_pos_test   = sub {$_[0]=~/^(top|bottom|right|left|outside|below)+$/};
my $sml_test       = sub {$_[0]=~/^(small|medium|large)$/};
my $linestyle_test = sub {$_[0]=~/^(lines|linespoints|dots|points|steps)$/};
my $words_test     = sub {$_[0]=~/^((\w+\b*)+$/};
##
## Default values for attributes of elements
##
my %plot_defaults = 
    (
     height       => {default => 200,       test => $int_test  },
     width        => {default => 200,       test => $int_test  },
     bgcolor      => {default => 'xffffff', test => $color_test},
     fgcolor      => {default => 'x000000', test => $color_test},
     transparent  => {default => 'off',     test => $onoff_test},
     grid         => {default => 'off',     test => $onoff_test},
     border       => {default => 'on',      test => $onoff_test},
     font         => {default => 'medium',  test => $sml_test  }
     );

my %key_defaults = 
    (
     title => { default => '',          test => $words_test  },
     box   => { default => 'off',       test => $onoff_test  },
     pos   => { default => 'top right', test => $key_pos_test}
     );

my %label_defaults = 
    (
     xpos    => {default => 0,         test => $real_test                   },
     ypos    => {default => 0,         test => $real_test                   },
     justify => {default => 'left',    
                 test => sub {$_[0]=~/^(left|right|center)$/}}
     );

my %axis_defaults = 
    (
     color     => {default => 'x000000', test => $color_test},
#     thickness => {default => 1,         test => $int_test  },
     xmin      => {default => -10.0,     test => $real_test },
     xmax      => {default =>  10.0,     test => $real_test },
     ymin      => {default => -10.0,     test => $real_test },
     ymax      => {default =>  10.0,     test => $real_test }
     );

my %curve_defaults = 
    (
     color     => {default => 'x000000', test => $color_test      },
     name      => {default => 'x000000', test => sub {$_[0]=~/^[\w ]*$/} },
     linestyle => {default => 'lines',   test => $linestyle_test  }
     );

##
## End of defaults
##
my (%plot,%key,%axis,$title,$xlabel,$ylabel,@labels,@curves);

sub start_plot {
    %plot = '';   %key='';    %axis=''; 
    $title='';    $xlabel=''; $ylabel='';
    @labels = ''; @curves='';
    #
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
    my $result='';
    &Apache::lonxml::register('Apache::plot',
	     ('title','xlabel','ylabel','key','axis','label','curve'));
    push (@Apache::lonxml::namespace,'plot');
    ## Always evaluate the insides of the <plot></plot> tags
    my $inside = &Apache::lonxml::get_all_text("/plot",$$parser[-1]);
    $inside=&Apache::run::evaluate($inside,$safeeval,$$parstack[-1]);
    &Apache::lonxml::newparser($parser,\$inside);
    ##-------------------------------------------------------
    &get_attributes(\%plot,\%plot_defaults,$parstack,$safeeval,'plot');
    if ($target eq 'web') {
    }
    return '';
}

sub end_plot {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
    pop @Apache::lonxml::namespace;
    &Apache::lonxml::deregister('Apache::lonplot',
	('title','xlabel','ylabel','key','axis','label','curve'));
    my $result = '';
    if ($target eq 'web') {
	## Determine filename -- Need to use the 'id' thingy that Gerd 
	## mentioned.
	my $tmpdir = '/home/httpd/perl/tmp/';
	my $filename = $tmpdir.$ENV{'user.name'}.'_'.$ENV{'user.domain'}.
	    '_plot.data';
	my $usersees=md5_base64($filename.'_'.$ENV{'REMOTE_ADDR'});
	
	## Write the plot description to the file
	my $fh=&Apache::File->new('/home/httpd/perl/tmp/'.$realname);
	&write_gnuplot_file($fh);
	## return image tag for the plot
	$result = '<img src=\"/cgi-bin/plot.cgi?'.$usersees.'"';
    }
    return $result;
}

##----------------------------------------------------------------- key
sub start_key {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
    my $result='';
    &get_attributes(\%key,\%key_defaults,$parstack,$safeeval,$tagstack);
    if ($target eq 'web') {
	# This routine should never return anything.
    }
    return $result;
}

sub end_key {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
    my $result = '';
    if ($target eq 'web') {
	# This routine should never return anything.
    }
    return $result;
}
##------------------------------------------------------------------- title
sub start_title {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
    $title = &Apache::lonxml::get_all_text("/title",$$parser[-1]);
    my $result='';
    if ($target eq 'web') {
	# This routine should never return anything.
    }
    return $result;
}

sub end_title {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
    my $result = '';
    if ($target eq 'web') {
	# This routine should never return anything.
    }
    return $result;
}
##------------------------------------------------------------------- xlabel
sub start_xlabel {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
    my $result='';
    $xlabel = &Apache::lonxml::get_all_text("/xlabel",$$parser[-1]);
    if ($target eq 'web') {
	# This routine should never return anything.
    }
    return $result;
}

sub end_xlabel {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
    my $result = '';
    if ($target eq 'web') {
	# This routine should never return anything.
    }
    return $result;
}
##------------------------------------------------------------------- ylabel
sub start_ylabel {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
    my $result='';
    $ylabel = &Apache::lonxml::get_all_text("/ylabel",$$parser[-1]);
    if ($target eq 'web') {
	# This routine should never return anything.
    }
    return $result;
}

sub end_ylabel {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
    my $result = '';
    if ($target eq 'web') {
	# This routine should never return anything.
    }
    return $result;
}
##------------------------------------------------------------------- label
sub start_label {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
    my $result='';
    my %label;
    &get_attributes($label,\%label_defaults,$parstack,$safeeval,$tagstack);
    $label->{'text'} = &Apache::lonxml::get_all_text("/label",$$parser[-1]);
    push(@labels,\%label);
    if ($target eq 'web') {
	# This routine should never return anything.
    }
    return $result;
}

sub end_label {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
    my $result = '';
    if ($target eq 'web') {
	# This routine should never return anything.
    }
    return $result;
}

##------------------------------------------------------------------- curve
sub start_curve {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
    my $result='';
    my %curve;
    &get_attributes($curve,\%curve_defaults,$parstack,$safeeval,$tagstack);
    push (@curves,$curve);
    &Apache::lonxml::register('Apache::lonplot',('function','data'));
    push (@Apache::lonxml::namespace,'curve');
    if ($target eq 'web') {
	# This routine should never return anything.
    }
    return $result;
}

sub end_curve {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
    my $result = '';
    pop @Apache::lonxml::namespace;
    &Apache::lonxml::deregister('Apache::lonplot',('function','data'));
    if ($target eq 'web') {
	# This routine should never return anything.
    }
    return $result;
}
##------------------------------------------------------------ curve function
sub start_function {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
    my $result='';
    if (exists($curves[-1]->{'data'}) {
	&Apache::lonxml::warning('Use of <function> precludes use of <data>.  The <data> will be omitted in favor of the <function> declaration.');
	delete($curves[-1]->{'data'});
    }
    $curves[-1]->{'function'} = 
	&Apache::lonxml::get_all_text("/function",$$parser[-1]);
    if ($target eq 'web') {
	# This routine should never return anything.
    }
    return $result;
}

sub end_function {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
    my $result = '';
    if ($target eq 'web') {
	# This routine should never return anything.
    }
    return $result;
}
##------------------------------------------------------------ curve  data
sub start_data {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
    my $result='';
    if (exists($curves[-1]->{'function'})) {
	&Apache::lonxml::warning('Use of <data> precludes use of <function>.  The <function> will be omitted in favor of the <data> declaration.');
	delete($curves[-1]->{'function'});
    }
    my $datatext = &Apache::lonxml::get_all_text("/data",$$parser[-1]);
    $datatext =~ s/(\s+$|^\s+)//g;
    $datatext =~ s/\s+/ /g;
    if ($datatext !~ /^(([+-]?\d*\.?\d*)[, ]?)+$/) {
	&Apache::lonxml::warning('Malformed data: '.$datatext);
	$datatext = '';
    }
    # Need to do some error checking on the @data array - 
    # make sure it's all numbers and make sure each array 
    # is of the same length.
    my @data = split /[, ]/,$datatext;
    push( @{$curves[-1]->{'data'}},\@data;
    if ($target eq 'web') {
	# This routine should never return anything.
    }
    return $result;
}

sub end_data {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
    my $result = '';
    if ($target eq 'web') {
	# This routine should never return anything.
    }
    return $result;
}

##------------------------------------------------------------------- axis
sub start_axis {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
    my $result='';
    &get_attributes(\%axis,\%label_defaults,$parstack,$safeeval,$tagstack);
    if ($target eq 'web') {
	# This routine should never return anything.
    }
    return $result;
}

sub end_axis {
    my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
    my $result = '';
    if ($target eq 'web') {
	# This routine should never return anything.
    }
    return $result;
}

##------------------------------------------------------------------- misc
sub get_attributes{
    %values   = %{shift};
    %defaults = %{shift};
    $parstack = shift;
    $safeeval = shift;
    $tag      = shift;
    my $attr;
    foreach $attr (keys %defaults) {
	$values{$attr} = &Apache::lonxml::get_param($attr,$parstack,$safeeval);
	if ($values{$attr} eq '' | !defined($values{$attr})) {
	    $values{$attr} = $defaults{$attr};
	    next;
	}
	my $test = $defaults{$attr}->{'test'};
	if (! &$test($values{$attr})) {
	    &Apache::lonxml::warning
		($tag.':'.$attr.': Bad value.'.'Replacing your value with : '
		 .$defaults{$attr} );
	    $values{$attr} = $defaults{$attr};
    }
    return ;
}

sub write_gnuplot_file {
    my $fh = shift;
    my $gnuplot_input = '';
    # Collect all the colors
    my @Colors;
    push @Colors, $plot{'bgcolor'};
    push @Colors, $plot{'fgcolor'}; 
    push @Colors, $axis{'color'};
    push @Colors, $axis{'color'}; 
    foreach $curve (@Curves) {
	push @Colors, ($curve{'color'} ne '' ? 
		       $curve{'color'}       : 
		       $plot{'fgcolor'}      );
    }
    # set term
    $gnuplot_input .= 'set term gif ';
    $gnuplot_input .= 'transparent ' if ($plot{'transparent'} eq 'on');
    $gnuplot_input .= $plot{'font'} . ' ';
    $gnuplot_input .= 'size ' . $plot{'width'} . ' ';
    $gnuplot_input .= $plot{'height'} . ' ';
    $gnuplot_input .= "@Colors\n";
    # grid
    $gnuplot_input .= ($plot->{'grid'} eq 'on' ?
		       'set grid\n'            :
		       ''                      );
    # border
    $gnuplot_input .= ($plot->{'border'} eq 'on'?
		       'set border\n'           :
		       'set noborder\n'         );    # title, xlabel, ylabel
    {
    $gnuplot_input .<<"ENDLABELS";
set title  $title->{'text'}
set xlabel $xlabel->{'text'}
set ylabel $ylabel->{'text'}
set xrange $axis->{'xmin'}:$axis->{'xmax'}
set yrange $axis->{'ymin'}:$axis->{'ymax'}
ENDLABELS
    }
    # Key
    if (defined($key{'pos'})) {
	$gnuplot_input .= 'set key '.$key->{'pos'}.' ';
	$gnuplot_input .= ($key->{'box'} eq 'on' ? 'box ' : 'nobox ');
	if ($key->{'title'} ne '') {
	    $gnuplot_input .= 'title "'$key->{'title'}.'"\n';
	} else {
	    $gnuplot_input .= '\n';
	}
    } else {
	$gnuplot_input .= 'set nokey\n';
    }    
    # axis
    $gnuplot_input .= 'set xrange ['.$axis{'xmin'}.':'.$axis{'xmin'}.']\n';
    $gnuplot_input .= 'set yrange ['.$axis{'ymin'}.':'.$axis{'ymin'}.']\n';
    # labels
    foreach $label (@labels) {
	$gnuplot_input .= 'set label "'.$label->{'text'}.'" at '.
	    $label->{'x'}.','.$label->{'y'}.'\n';
    }
    # curves
    $gnuplot_input .= 'plot ';
    my $datatext = '';
    foreach $curve (@curves) {
	if (exists($curve->{'function'})) {
	    $gnuplot_input.= $curve->{'function'}.' with '.$curve->{'linestyle'};
	} elsif (exists($curve->{'data'})) {
	    $gnuplot_input.= '\'-\' with '.$curve->{'linestyle'};
	    my @Data = @{$curve->{'data'}};
	    for ($i =0; $i<=$#Data; $i++) {
		foreach $dataset (@Data) {
		    $datatext .= $dataset[$i] . ' ';
		}
		$datatext .='\n';
	    }
	    $datatext .='\n';
	}
    }
    $gnuplot_input .= $datatext;
    print $fh $gnuplot_input;
}

1;
__END__