--- loncom/xml/lonplot.pm	2001/12/19 19:22:52	1.8
+++ loncom/xml/lonplot.pm	2001/12/28 19:40:47	1.23
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # Dynamic plot
 #
-# $Id: lonplot.pm,v 1.8 2001/12/19 19:22:52 matthew Exp $
+# $Id: lonplot.pm,v 1.23 2001/12/28 19:40:47 matthew Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -26,99 +26,272 @@
 # http://www.lon-capa.org/
 #
 # 12/15/01 Matthew
-# 12/18 Matthew
+# 12/17 12/18 12/19 12/20 12/21 12/27 12/28 Matthew
 package Apache::lonplot;
+
 use strict;
+use Apache::File;
 use Apache::response;
 use Apache::lonxml;
-use Digest::MD5  qw(md5 md5_hex md5_base64);
+use Apache::edit;
 
 sub BEGIN {
   &Apache::lonxml::register('Apache::lonplot',('plot'));
 }
 
+## 
+## Description of data structures:
+##
+##  %plot       %key    %axis
+## --------------------------
+##  height      title   color
+##  width       box     xmin
+##  bgcolor     pos     xmax
+##  fgcolor             ymin
+##  transparent         ymax
+##  grid
+##  border
+##  font
+##  align
+##
+##  @labels: $labels[$i] = \%label
+##           %label: text, xpos, ypos, justify
 ##
-## Tests used in checking the validitity of input
+##  @curves: $curves[$i] = \%curve
+##           %curve: name, linestyle, ( function | data )
 ##
-my $int_test       = sub {$_[0]=~/^\d+$/};
-my $real_test      = sub {$_[0]=~/^[+-]?\d*\.?\d*$/};
-my $color_test     = sub {$_[0]=~/^x[\da-f]{6}$/};
+##  $curves[$i]->{'data'} = [ [x1,x2,x3,x4],
+##                            [y1,y2,y3,y4] ]
+##
+
+###################################################################
+##                                                               ##
+##        Tests used in checking the validitity of input         ##
+##                                                               ##
+###################################################################
+my $int_test       = sub {$_[0]=~s/\s+//g;$_[0]=~/^\d+$/};
+my $real_test      = 
+    sub {$_[0]=~s/\s+//g;$_[0]=~/^[+-]?\d*\.?\d*([eE][+-]\d+)?$/};
+my $color_test     = sub {$_[0]=~s/\s+//g;$_[0]=~/^x[\da-f]{6}$/};
 my $onoff_test     = sub {$_[0]=~/^(on|off)$/};
-my $key_pos_test   = sub {$_[0]=~/^(top|bottom|right|left|outside|below)+$/};
+my $key_pos_test   = sub {$_[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 $words_test     = sub {$_[0]=~s/\s+/ /g;$_[0]=~/^([\w\(\)]+ ?)+$/};
+
+###################################################################
+##                                                               ##
+##                      Attribute metadata                       ##
+##                                                               ##
+###################################################################
 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  }
+     height       => {
+	 default     => 200,
+	 test        => $int_test,
+	 description => 'vertical size of image (pixels)',
+	 edit_type   => 'entry' 
+	 },
+     width        => {
+	 default     => 200,
+	 test        => $int_test,
+	 description => 'horizontal size of image (pixels)',
+	 edit_type   => 'entry'
+	 },
+     bgcolor      => {
+	 default     => 'xffffff',
+	 test        => $color_test, 
+	 description => 'background color of image (xffffff)',
+	 edit_type   => 'entry'
+	 },
+     fgcolor      => {
+	 default     => 'x000000',
+	 test        => $color_test,
+	 description => 'foreground color of image (x000000)',
+	 edit_type   => 'entry' 
+	 },
+     transparent  => {
+	 default     => 'off',
+	 test        => $onoff_test, 
+	 description => '',
+	 edit_type   => 'on_off'
+	 },
+     grid         => {
+	 default     => 'off',
+	 test        => $onoff_test, 
+	 description => '',
+	 edit_type   => 'on_off'
+	 },
+     border       => {
+	 default     => 'on',
+	 test        => $onoff_test, 
+	 description => '',
+	 edit_type   => 'on_off'
+	 },
+     font         => {
+	 default     => 'medium',
+	 test        => $sml_test,
+	 description => 'Size of font to use',
+	 edit_type   => 'choice',
+	 choices     => ['small','medium','large']
+	 },
+     align        => {
+	 default     => 'left',
+	 test        => sub {$_[0]=~/^(left|right|center)$/},
+	 description => 'alignment for image in html',
+	 edit_type   => 'choice',
+	 choices     => ['left','right','center']
+	 } 
      );
 
 my %key_defaults = 
     (
-     title => { default => '',          test => $words_test  },
-     box   => { default => 'off',       test => $onoff_test  },
-     pos   => { default => 'top right', test => $key_pos_test}
+     title => { 
+	 default => '',
+	 test => $words_test,
+	 description => 'Title of key',
+	 edit_type   => 'entry'
+	 },
+     box   => { 
+	 default => 'off',
+	 test => $onoff_test,
+	 description => 'Draw a box around the key?',
+	 edit_type   => 'on_off'
+	 },
+     pos   => { 
+	 default => 'top right', 
+	 test => $key_pos_test, 
+	 description => 'position of the key on the plot',
+	 edit_type   => 'choice',
+	 choices     => ['top left','top right','bottom left','bottom right',
+			 'outside','below']
+	 }
      );
 
 my %label_defaults = 
     (
-     xpos    => {default => 0,         test => $real_test                   },
-     ypos    => {default => 0,         test => $real_test                   },
-     justify => {default => 'left',    
-                 test => sub {$_[0]=~/^(left|right|center)$/}}
+     xpos    => {
+	 default => 0,
+	 test => $real_test,
+	 description => 'x position of label (graph coordinates)',
+	 edit_type   => 'entry'
+	 },
+     ypos    => {
+	 default => 0, 
+	 test => $real_test,
+	 description => 'y position of label (graph coordinates)',
+	 edit_type   => 'entry'
+	 },
+     justify => {
+	 default => 'left',    
+	 test => sub {$_[0]=~/^(left|right|center)$/},
+	 description => 'justification of the label text on the plot',
+	 edit_type   => 'choice',
+	 choices     => ['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 }
+     color     => {
+	 default => 'x000000', 
+	 test => $color_test,
+	 description => 'color of axes (x000000)',
+	 edit_type   => 'entry'
+	 },
+     xmin      => {
+	 default => '-10.0',
+	 test => $real_test,
+	 description => 'minimum x-value shown in plot',
+	 edit_type   => 'entry'
+	 },
+     xmax      => {
+	 default => ' 10.0',
+	 test => $real_test,
+	 description => 'maximum x-value shown in plot',	 
+	 edit_type   => 'entry'
+	 },
+     ymin      => {
+	 default => '-10.0',
+	 test => $real_test,
+	 description => 'minimum y-value shown in plot',	 
+	 edit_type   => 'entry'
+	 },
+     ymax      => {
+	 default => ' 10.0',
+	 test => $real_test,
+	 description => 'maximum y-value shown in plot',	 
+	 edit_type   => 'entry'
+	 },
+     linestyle => {
+	 default => 'points',
+	 test => $linestyle_test,
+	 description => 'Style of the axis lines',
+	 edit_type   => 'choice',
+	 choices     => ['lines','linespoints','dots','points']
+	 }
      );
 
 my %curve_defaults = 
     (
-     color     => {default => 'x000000', test => $color_test      },
-     name      => {default => 'x000000', test => sub {$_[0]=~/^[\w ]*$/} },
-     linestyle => {default => 'lines',   test => $linestyle_test  }
+     color     => {
+	 default => 'x000000',
+	 test => $color_test,
+	 description => 'color of curve (x000000)',
+	 edit_type   => 'entry'
+	 },
+     name      => {
+	 default => '',
+	 test => $words_test,
+	 description => 'name of curve to appear in key',
+	 edit_type   => 'entry'
+	 },
+     linestyle => {
+	 default => 'lines',
+	 test => $linestyle_test,
+	 description => 'Style of the axis lines',
+	 edit_type   => 'choice',
+	 choices     => ['lines','linespoints','dots','points','steps']
+	 }
      );
 
-##
-## End of defaults
-##
+###################################################################
+##                                                               ##
+##                    parsing and edit rendering                 ##
+##                                                               ##
+###################################################################
 my (%plot,%key,%axis,$title,$xlabel,$ylabel,@labels,@curves);
 
 sub start_plot {
-    %plot = '';   %key='';    %axis=''; 
-    $title='';    $xlabel=''; $ylabel='';
-    @labels = ''; @curves='';
+    %plot    = ();      %key     = ();      %axis   = (); 
+    $title   = undef;   $xlabel  = undef;   $ylabel = undef;
+    $#labels = -1;      $#curves = -1;
     #
     my ($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') {
+	&Apache::lonxml::register('Apache::lonplot',
+	      ('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,
+			$tagstack->[-1]);
+    } elsif ($target eq 'edit') {
+	$result .= &Apache::edit::tag_start($target,$token);
+	$result .= &edit_attributes($target,$token,\%plot_defaults);
+    } elsif ($target eq 'modified') {
+	my $constructtag=&Apache::edit::get_new_args
+	    ($token,$parstack,$safeeval,keys %plot_defaults);
+	if ($constructtag) {
+	    $result = &Apache::edit::rebuild_tag($token);
+	    $result.= &Apache::edit::handle_insert();
+	}
     }
-    return '';
+    return $result;
 }
 
 sub end_plot {
@@ -128,18 +301,26 @@ sub end_plot {
 	('title','xlabel','ylabel','key','axis','label','curve'));
     my $result = '';
     if ($target eq 'web') {
-	## Determine filename -- Need to use the 'id' thingy that Gerd 
-	## mentioned.
+	&check_inputs(); # Make sure we have all the data we need
+	##
+	## Determine filename
 	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'});
-	
+	my $filename = $ENV{'user.name'}.'_'.$ENV{'user.domain'}.
+	    '_'.time.'_'.$$.'_plot.data';
 	## Write the plot description to the file
-	my $fh=&Apache::File->new('/home/httpd/perl/tmp/'.$realname);
-	&write_gnuplot_file($fh);
+	my $fh=Apache::File->new(">$tmpdir$filename");
+	print $fh &write_gnuplot_file();
+	close($fh);
 	## return image tag for the plot
-	$result = '<img src=\"/cgi-bin/plot.cgi?'.$usersees.'"';
+	$result .= <<"ENDIMAGE";
+<img src    = "/cgi-bin/plot.gif?$filename" 
+     width  = "$plot{'width'}" 
+     height = "$plot{'height'}"
+     align  = "$plot{'align'}"
+     alt    = "/cgi-bin/plot.gif?$filename" />
+ENDIMAGE
+    } elsif ($target eq 'edit') {
+	$result.=&Apache::edit::tag_end($target,$token);
     }
     return $result;
 }
@@ -148,9 +329,19 @@ sub end_plot {
 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.
+	&get_attributes(\%key,\%key_defaults,$parstack,$safeeval,
+		    $tagstack->[-1]);
+    } elsif ($target eq 'edit') {
+	$result .= &Apache::edit::tag_start($target,$token);
+	$result .= &edit_attributes($target,$token,\%key_defaults);
+    } elsif ($target eq 'modified') {
+	my $constructtag=&Apache::edit::get_new_args
+	    ($token,$parstack,$safeeval,keys %key_defaults);
+	if ($constructtag) {
+	    $result = &Apache::edit::rebuild_tag($token);
+	    $result.= &Apache::edit::handle_insert();
+	}
     }
     return $result;
 }
@@ -159,17 +350,27 @@ sub end_key {
     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
     my $result = '';
     if ($target eq 'web') {
-	# This routine should never return anything.
+    } elsif ($target eq 'edit') {
+	$result.=&Apache::edit::tag_end($target,$token);
     }
     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.
+	$title = &Apache::lonxml::get_all_text("/title",$$parser[-1]);
+    } elsif ($target eq 'edit') {
+	$result.=&Apache::edit::tag_start($target,$token);
+	my $text=&Apache::lonxml::get_all_text("/title",$$parser[-1]);
+	$result.='</td></tr><tr><td colspan="3">'.
+	    &Apache::edit::editfield('',$text,'',20,1).
+	    &Apache::edit::end_table();
+    } elsif ($target eq 'modified') {
+	my $text=$$parser[-1]->get_text("/function");
+	$result.=&Apache::edit::modifiedfield($token);
     }
     return $result;
 }
@@ -178,7 +379,8 @@ sub end_title {
     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
     my $result = '';
     if ($target eq 'web') {
-	# This routine should never return anything.
+    } elsif ($target eq 'edit') {
+	$result.=&Apache::edit::tag_end($target,$token);
     }
     return $result;
 }
@@ -186,9 +388,17 @@ sub end_title {
 sub start_xlabel {
     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
     my $result='';
-    $xlabel = &Apache::lonxml::get_all_text("/xlabel",$$parser[-1]);
     if ($target eq 'web') {
-	# This routine should never return anything.
+	$xlabel = &Apache::lonxml::get_all_text("/xlabel",$$parser[-1]);
+    } elsif ($target eq 'edit') {
+	$result.=&Apache::edit::tag_start($target,$token);
+	my $text=&Apache::lonxml::get_all_text("/xlabel",$$parser[-1]);
+	$result.='</td></tr><tr><td colspan="3">'.
+	    &Apache::edit::editfield('',$text,'',20,1).
+	    &Apache::edit::end_table();
+    } elsif ($target eq 'modified') {
+	my $text=$$parser[-1]->get_text("/function");
+	$result.=&Apache::edit::modifiedfield($token);
     }
     return $result;
 }
@@ -197,17 +407,27 @@ sub end_xlabel {
     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
     my $result = '';
     if ($target eq 'web') {
-	# This routine should never return anything.
+    } elsif ($target eq 'edit') {
+	$result.=&Apache::edit::tag_end($target,$token);
     }
     return $result;
 }
+
 ##------------------------------------------------------------------- ylabel
 sub start_ylabel {
     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
     my $result='';
-    $ylabel = &Apache::lonxml::get_all_text("/ylabel",$$parser[-1]);
     if ($target eq 'web') {
-	# This routine should never return anything.
+	$ylabel = &Apache::lonxml::get_all_text("/ylabel",$$parser[-1]);
+    } elsif ($target eq 'edit') {
+	$result .= &Apache::edit::tag_start($target,$token);
+	my $text = &Apache::lonxml::get_all_text("/ylabel",$$parser[-1]);
+	$result .= '</td></tr><tr><td colspan="3">'.
+	    &Apache::edit::editfield('',$text,'',20,1).
+	    &Apache::edit::end_table();
+    } elsif ($target eq 'modified') {
+	my $text=$$parser[-1]->get_text("/function");
+	$result.=&Apache::edit::modifiedfield($token);
     }
     return $result;
 }
@@ -216,20 +436,42 @@ sub end_ylabel {
     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
     my $result = '';
     if ($target eq 'web') {
-	# This routine should never return anything.
+    } elsif ($target eq 'edit') {
+	$result.=&Apache::edit::tag_end($target,$token);
     }
     return $result;
 }
+
 ##------------------------------------------------------------------- label
 sub start_label {
     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
     my $result='';
-    my %label;
-    &get_attributes($label,\%label_defaults,$parstack,$safeeval,$tagstack);
-    $label->{'text'} = &Apache::lonxml::get_all_text("/label",$$parser[-1]);
-    push(@labels,\%label);
     if ($target eq 'web') {
-	# This routine should never return anything.
+	my %label;
+	&get_attributes(\%label,\%label_defaults,$parstack,$safeeval,
+		    $tagstack->[-1]);
+	$label{'text'} = &Apache::lonxml::get_all_text("/label",$$parser[-1]);
+	if (! &$words_test($label{'text'})) {
+	    # I should probably warn about it, too.
+	    $label{'text'} = 'Illegal text';
+	}
+	push(@labels,\%label);
+    } elsif ($target eq 'edit') {
+	$result .= &Apache::edit::tag_start($target,$token);
+	$result .= &edit_attributes($target,$token,\%label_defaults);
+	my $text = &Apache::lonxml::get_all_text("/label",$$parser[-1]);
+	$result .= '</td></tr><tr><td colspan="3">'.
+	    &Apache::edit::editfield('',$text,'',20,1).
+	    &Apache::edit::end_table();
+    } elsif ($target eq 'modified') {
+	my $constructtag=&Apache::edit::get_new_args
+	    ($token,$parstack,$safeeval,keys %label_defaults);
+	if ($constructtag) {
+	    $result = &Apache::edit::rebuild_tag($token);
+	    $result.= &Apache::edit::handle_insert();
+	}
+	my $text=$$parser[-1]->get_text("/label");
+	$result.=&Apache::edit::modifiedfield($token);
     }
     return $result;
 }
@@ -238,7 +480,8 @@ sub end_label {
     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
     my $result = '';
     if ($target eq 'web') {
-	# This routine should never return anything.
+    } elsif ($target eq 'edit') {
+	$result.=&Apache::edit::tag_end($target,$token);
     }
     return $result;
 }
@@ -247,13 +490,23 @@ sub end_label {
 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.
+	my %curve;
+	&get_attributes(\%curve,\%curve_defaults,$parstack,$safeeval,
+		    $tagstack->[-1]);
+	push (@curves,\%curve);
+	&Apache::lonxml::register('Apache::lonplot',('function','data'));
+	push (@Apache::lonxml::namespace,'curve');
+    } elsif ($target eq 'edit') {
+	$result .= &Apache::edit::tag_start($target,$token);
+	$result .= &edit_attributes($target,$token,\%curve_defaults);
+    } elsif ($target eq 'modified') {
+	my $constructtag=&Apache::edit::get_new_args
+	    ($token,$parstack,$safeeval,keys %label_defaults);
+	if ($constructtag) {
+	    $result = &Apache::edit::rebuild_tag($token);
+	    $result.= &Apache::edit::handle_insert();
+	}
     }
     return $result;
 }
@@ -261,25 +514,37 @@ sub start_curve {
 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.
+	pop @Apache::lonxml::namespace;
+	&Apache::lonxml::deregister('Apache::lonplot',('function','data'));
+    } elsif ($target eq 'edit') {
+	$result.=&Apache::edit::tag_end($target,$token);
     }
     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 ($target eq 'web') {
-	# This routine should never return anything.
+	if (exists($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",$$parser[-1]);
+    } elsif ($target eq 'edit') {
+	$result .= &Apache::edit::tag_start($target,$token);
+	my $text = &Apache::lonxml::get_all_text("/function",$$parser[-1]);
+	$result .= '</td></tr><tr><td colspan="3">'.
+	    &Apache::edit::editfield('',$text,'',20,1).
+	    &Apache::edit::end_table();
+
+    } elsif ($target eq 'modified') {
+	# Why do I do this?
+	my $text=$$parser[-1]->get_text("/function");
+	$result.=&Apache::edit::modifiedfield($token);
     }
     return $result;
 }
@@ -288,32 +553,59 @@ sub end_function {
     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
     my $result = '';
     if ($target eq 'web') {
-	# This routine should never return anything.
+    } elsif ($target eq 'edit') {
     }
     return $result;
 }
+
 ##------------------------------------------------------------ curve  data
 sub start_data {
     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
     my $result='';
-    if (exists($curves[-1]->{'function'})) {
-	&Apache::lonxml::warning('Use of <data> precludes use of <function>.  The <function> will be omitted in favor of the <data> declaration.');
-	delete($curves[-1]->{'function'});
-    }
-    my $datatext = &Apache::lonxml::get_all_text("/data",$$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.
+	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",$$parser[-1]);
+	$datatext =~ s/\s+/ /g;  
+	# Need to do some error checking on the @data array - 
+	# make sure it's all numbers and make sure each array 
+	# is of the same length.
+	my @data;
+	if ($datatext =~ /,/) {
+	    @data = split /,/,$datatext;
+	} else { # Assume it's space seperated.
+	    @data = split / /,$datatext;
+	}
+	for (my $i=0;$i<=$#data;$i++) {
+	    # Check that it's non-empty
+	    if (! defined($data[$i])) {
+		&Apache::lonxml::warning(
+		    'undefined <data> value.  Replacing with '.
+		    ' pi/e = 1.15572734979092');
+		$data[$i] = 1.15572734979092;
+	    }
+	    # Check that it's a number
+	    if (! &$real_test($data[$i]) & ! &$int_test($data[$i])) {
+		&Apache::lonxml::warning(
+		    'Bad <data> value of '.$data[$i].'  Replacing with '.
+		    ' pi/e = 1.15572734979092');
+		$data[$i] = 1.15572734979092;
+	    }
+	}
+	push  @{$curves[-1]->{'data'}},\@data;
+    } elsif ($target eq 'edit') {
+	$result .= &Apache::edit::tag_start($target,$token);
+	my $text = &Apache::lonxml::get_all_text("/data",$$parser[-1]);
+	$result .= '</td></tr><tr><td colspan="3">'.
+	    &Apache::edit::editfield('',$text,'',20,1).
+	    &Apache::edit::end_table();
+    } elsif ($target eq 'modified') {
+	my $text=$$parser[-1]->get_text("/data");
+	$result.=&Apache::edit::modifiedfield($token);
     }
     return $result;
 }
@@ -322,7 +614,7 @@ sub end_data {
     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
     my $result = '';
     if ($target eq 'web') {
-	# This routine should never return anything.
+    } elsif ($target eq 'edit') {
     }
     return $result;
 }
@@ -331,9 +623,13 @@ sub end_data {
 sub start_axis {
     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
     my $result='';
-    &get_attributes(\%axis,\%label_defaults,$parstack,$safeeval,$tagstack);
     if ($target eq 'web') {
-	# This routine should never return anything.
+	&get_attributes(\%axis,\%axis_defaults,$parstack,$safeeval,
+			$tagstack->[-1]);
+    } elsif ($target eq 'edit') {
+	$result .= &Apache::edit::tag_start($target,$token);
+	$result .= &edit_attributes($target,$token,\%axis_defaults);
+    } elsif ($target eq 'modified') {
     }
     return $result;
 }
@@ -342,119 +638,270 @@ sub end_axis {
     my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_;
     my $result = '';
     if ($target eq 'web') {
-	# This routine should never return anything.
+    } elsif ($target eq 'edit') {
+	$result.=&Apache::edit::tag_end($target,$token);
+    } elsif ($target eq 'modified') {
+	my $constructtag=&Apache::edit::get_new_args
+	    ($token,$parstack,$safeeval,keys %axis_defaults);
+	if ($constructtag) {
+	    $result = &Apache::edit::rebuild_tag($token);
+	    $result.= &Apache::edit::handle_insert();
+	}
     }
     return $result;
 }
 
+###################################################################
+##                                                               ##
+##        Utility Functions                                      ##
+##                                                               ##
+###################################################################
+
+##----------------------------------------------------------- set_defaults
+sub set_defaults {
+    my ($var,$defaults) = @_;
+    my $key;
+    foreach $key (keys %$defaults) {
+	$var->{$key} = $defaults->{$key}->{'default'};
+    }
+}
+
 ##------------------------------------------------------------------- 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};
+    my ($values,$defaults,$parstack,$safeeval,$tag) = @_;
+    foreach my $attr (keys %{$defaults}) {
+	$values->{$attr} = 
+	    &Apache::lonxml::get_param($attr,$parstack,$safeeval);
+	if ($values->{$attr} eq '' | !defined($values->{$attr})) {
+	    $values->{$attr} = $defaults->{$attr}->{'default'};
 	    next;
 	}
-	my $test = $defaults{$attr}->{'test'};
-	if (! &$test($values{$attr})) {
+	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};
+		 .$defaults->{$attr}->{'default'} );
+	    $values->{$attr} = $defaults->{$attr}->{'default'};
+	}
     }
     return ;
 }
-
+##------------------------------------------------------- write_gnuplot_file
 sub write_gnuplot_file {
-    my $fh = shift;
     my $gnuplot_input = '';
+    my $curve;
     # 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'}       : 
-		       $plot{'fgcolor'}      );
+    push @Colors, (defined($axis{'color'})?$axis{'color'}:$plot{'fgcolor'});
+    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'} . ' ';
+    $gnuplot_input .= 'size '.$plot{'width'}.','.$plot{'height'}.' ';
     $gnuplot_input .= "@Colors\n";
     # grid
-    $gnuplot_input .= ($plot->{'grid'} eq 'on' ?
-		       'set grid\n'            :
-		       ''                      );
+    $gnuplot_input .= 'set grid'.$/ if ($plot{'grid'} eq 'on');
     # 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
+    $gnuplot_input .= ($plot{'border'} eq 'on'?
+		       'set border'.$/           :
+		       'set noborder'.$/         );    # title, xlabel, ylabel
+    $gnuplot_input .= "set output\n";
+    $gnuplot_input .= "set title  \"$title\"\n"  if (defined($title)) ;
+    $gnuplot_input .= "set xlabel \"$xlabel\"\n" if (defined($xlabel));
+    $gnuplot_input .= "set ylabel \"$ylabel\"\n" if (defined($ylabel));
+    if (%axis) {
+	$gnuplot_input .= "set xrange \[$axis{'xmin'}:$axis{'xmax'}\]\n";
+	$gnuplot_input .= "set yrange \[$axis{'ymin'}:$axis{'ymax'}\]\n";
     }
     # 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';
-	}
+    if (%key) {
+	$gnuplot_input .= 'set key '.$key{'pos'}.' ';
+	if ($key{'title'} ne '') {
+	    $gnuplot_input .= 'title "'.$key{'title'}.'" ';
+	} 
+	$gnuplot_input .= ($key{'box'} eq 'on' ? 'box ' : 'nobox ').$/;
     } 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';
+	$gnuplot_input .= 'set nokey'.$/;
+    }
     # labels
+    my $label;
     foreach $label (@labels) {
 	$gnuplot_input .= 'set label "'.$label->{'text'}.'" at '.
-	    $label->{'x'}.','.$label->{'y'}.'\n';
+	    $label->{'xpos'}.','.$label->{'ypos'}.' '.$label->{'justify'}.$/ ;
     }
     # curves
     $gnuplot_input .= 'plot ';
     my $datatext = '';
-    foreach $curve (@curves) {
+    for (my $i = 0;$i<=$#curves;$i++) {
+	$curve = $curves[$i];
+	$gnuplot_input.= ', ' if ($i > 0);
 	if (exists($curve->{'function'})) {
-	    $gnuplot_input.= $curve->{'function'}.' with '.$curve->{'linestyle'};
+	    $gnuplot_input.= 
+		$curve->{'function'}.' title "'.
+		$curve->{'name'}.'" with '.
+		$curve->{'linestyle'};
 	} elsif (exists($curve->{'data'})) {
-	    $gnuplot_input.= '\'-\' with '.$curve->{'linestyle'};
+	    $gnuplot_input.= '\'-\' title "'.
+		$curve->{'name'}.'" with '.
+		$curve->{'linestyle'};
 	    my @Data = @{$curve->{'data'}};
-	    for ($i =0; $i<=$#Data; $i++) {
+	    my @Data0 = @{$Data[0]};
+	    for (my $i =0; $i<=$#Data0; $i++) {
+		my $dataset;
 		foreach $dataset (@Data) {
-		    $datatext .= $dataset[$i] . ' ';
+		    $datatext .= $dataset->[$i] . ' ';
 		}
-		$datatext .='\n';
+		$datatext .= $/;
 	    }
-	    $datatext .='\n';
+	    $datatext .=$/;
 	}
     }
-    $gnuplot_input .= $datatext;
-    print $fh $gnuplot_input;
+    $gnuplot_input .= $/.$datatext;
+    return $gnuplot_input;
+}
+
+#---------------------------------------------- check_inputs
+sub check_inputs {
+    ## Note: no inputs, no outputs - this acts only on global variables.
+    ## Make sure we have all the input we need:
+    if (! %plot) { &set_defaults(\%plot,\%plot_defaults); }
+    if (! %key ) {} # No key for this plot, thats okay
+    if (! %axis) { &set_defaults(\%axis,\%axis_defaults); }
+    if (! defined($title )) {} # No title for this plot, thats okay
+    if (! defined($xlabel)) {} # No xlabel for this plot, thats okay
+    if (! defined($ylabel)) {} # No ylabel for this plot, thats okay
+    if ($#labels < 0) { }      # No labels for this plot, thats okay
+    if ($#curves < 0) { 
+	&Apache::lonxml::warning("No curves specified for plot!!!!");
+	return '';
+    }
+    my $curve;
+    foreach $curve (@curves) {
+	if (!defined($curve->{'function'})&&!defined($curve->{'data'})){
+	    &Apache::lonxml::warning("One of the curves specified did not contain any <data> or <function> declarations\n");
+	    return '';
+	}
+    }
+}
+
+#------------------------------------------------ make_edit
+sub edit_attributes {
+    my ($target,$token,$defaults) = @_;
+    my $result;
+    foreach my $attr (%$defaults) {
+	if ($defaults->{$attr}->{'edit_type'} eq 'entry') {
+	    $result .= &Apache::edit::text_arg(
+                 $defaults->{$attr}->{'description'},
+		 $attr,
+		 $token);
+	} elsif ($defaults->{$attr}->{'edit_type'} eq 'choice') {
+	    $result .= &Apache::edit::select_arg(
+		 $defaults->{$attr}->{'description'},
+		 $attr,
+		 $defaults->{$attr}->{'choices'},
+		 $token);
+	}
+    }
+    return $result;
 }
 
-1;
-__END__
 
+###################################################################
+##                                                               ##
+##           Insertion functions for editing plots               ##
+##                                                               ##
+###################################################################
+
+#------------------------------------------------ insert_xxxxxxx
+sub insert_plot {
+    my $result;
+    #  plot attributes
+    $result .= '<plot ';
+    foreach my $attr (%plot_defaults) {
+	$result .= '     '.$attr.' "'.$plot_defaults{$attr}->{'default'}.
+	    "\"\n";
+    }
+    $result .= ">\n";
+    # Add the components
+    $result .= &insert_key();
+    $result .= &insert_axis();
+    $result .= &insert_label();    
+    $result .= &insert_curve();
+    $result .= &insert_function();    
+    $result .= "</curve>\n";
+    $result .= &insert_curve();
+    $result .= &insert_data();    
+    $result .= "</curve>\n";
+    # close up the <plot>
+    $result .= "</plot>\n";
+    return $result;
+}
 
+sub insert_key {
+    my $result;
+    $result .= '    <key ';
+    foreach my $attr (%key_defaults) {
+	$result .= '         '.$attr.' "'.$key_defaults{$attr}->{'default'}.
+	    "\"\n";
+    }
+    $result .= "   />\n";
+    return $result;
+}
 
+sub insert_axis{
+    my $result;
+    $result .= '    <axis ';
+    foreach my $attr (%axis_defaults) {
+	$result .= '         '.$attr.' "'.$axis_defaults{$attr}->{'default'}.
+	    "\"\n";
+    }
+    $result .= "   />\n";
+    return $result;
+}
+
+sub insert_label {
+    my $result;
+    $result .= '    <label ';
+    foreach my $attr (%label_defaults) {
+	$result .= '         '.$attr.' "'.
+	    $label_defaults{$attr}->{'default'}."\"\n";
+    }
+    $result .= "   ></label>\n";
+    return $result;
+}
+
+sub insert_curve {
+    my $result;
+    $result .= '    <curve ';
+    foreach my $attr (%curve_defaults) {
+	$result .= '         '.$attr.' "'.
+	    $curve_defaults{$attr}->{'default'}."\"\n";
+    }
+    $result .= "    >\n";
+}
+
+sub insert_function {
+    my $result;
+    $result .= "<function></function>\n";
+    return $result;
+}
+
+sub insert_data {
+    my $result;
+    $result .= "     <data></data>\n";
+    $result .= "     <data></data>\n";
+    return $result;
+}
+
+##----------------------------------------------------------------------
+1;
+__END__