--- loncom/xml/lonplot.pm	2001/12/18 22:29:42	1.5
+++ loncom/xml/lonplot.pm	2001/12/19 18:27:30	1.6
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # Dynamic plot
 #
-# $Id: lonplot.pm,v 1.5 2001/12/18 22:29:42 matthew Exp $
+# $Id: lonplot.pm,v 1.6 2001/12/19 18:27:30 matthew Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -37,7 +37,6 @@ sub BEGIN {
   &Apache::lonxml::register('Apache::lonplot',('plot'));
 }
 
-
 ##
 ## Tests used in checking the validitity of input
 ##
@@ -75,7 +74,6 @@ my %label_defaults =
     (
      xpos    => {default => 0,         test => $real_test                   },
      ypos    => {default => 0,         test => $real_test                   },
-     color   => {default => 'x000000', test => $color_test                  },
      justify => {default => 'left',    
                  test => sub {$_[0]=~/^(left|right|center)$/}}
      );
@@ -83,7 +81,7 @@ my %label_defaults =
 my %axis_defaults = 
     (
      color     => {default => 'x000000', test => $color_test},
-     thickness => {default => 1,         test => $int_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 },
@@ -106,7 +104,7 @@ 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',
@@ -130,7 +128,8 @@ sub end_plot {
 	('title','xlabel','ylabel','key','axis','label','curve'));
     my $result = '';
     if ($target eq 'web') {
-	## Determine filename -- may need a better way later
+	## 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';
@@ -138,13 +137,7 @@ sub end_plot {
 	
 	## Write the plot description to the file
 	my $fh=&Apache::File->new('/home/httpd/perl/tmp/'.$realname);
-	# write plot values
-	# write title, xlabel, ylabel
-	# write key values
-	# write axis values
-	# write label values
-	# write curve values
-	## Ack! 
+	&write_gnuplot_file($fh);
 	## return image tag for the plot
 	$result = '<img src=\"/cgi-bin/plot.cgi?'.$usersees.'"';
     }
@@ -275,7 +268,6 @@ sub end_curve {
     }
     return $result;
 }
-
 ##------------------------------------------------------------ curve function
 sub start_function {
     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
@@ -300,7 +292,6 @@ sub end_function {
     }
     return $result;
 }
-
 ##------------------------------------------------------------ curve  data
 sub start_data {
     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
@@ -316,7 +307,11 @@ sub start_data {
 	&Apache::lonxml::warning('Malformed data: '.$datatext);
 	$datatext = '';
     }
-    push( @{$curves[-1]->{'data'}},$datatext;
+    # Need to do some error checking on the @data array - 
+    # make sure it's all numbers and make sure each array 
+    # is of the same length.
+    my @data = split /[, ]/,$datatext;
+    push( @{$curves[-1]->{'data'}},\@data;
     if ($target eq 'web') {
 	# This routine should never return anything.
     }
@@ -362,14 +357,93 @@ sub get_attributes{
     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{$attr});
+	    &Apache::lonxml::warning
+		($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";
+    # 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__