--- loncom/interface/lonprintout.pm	2005/07/25 10:27:51	1.379
+++ loncom/interface/lonprintout.pm	2005/08/16 10:25:15	1.386
@@ -1,7 +1,7 @@
 #  The LearningOnline Network
 # Printout
 #
-# $Id: lonprintout.pm,v 1.379 2005/07/25 10:27:51 foxr Exp $
+# $Id: lonprintout.pm,v 1.386 2005/08/16 10:25:15 foxr Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -44,6 +44,124 @@ use Apache::lonlocal;
 
 my $resources_printed = '';
 
+#
+#   Convert a numeric code to letters
+#
+sub num_to_letters {
+    my ($num) = @_;
+    my @nums= split('',$num);
+    my @num_to_let=('A'..'Z');
+    my $word;
+    foreach my $digit (@nums) { $word.=$num_to_let[$digit]; }
+    return $word;
+}
+#   Convert a letter code to numeric.
+#
+sub letters_to_num {
+    my ($letters) = @_;
+    my @letters = split('', uc($letters));
+    my %substitution;
+    my $digit = 0;
+    foreach my $letter ('A'..'J') {
+	$substitution{$letter} = $digit;
+	$digit++;
+    }
+    #  The substitution is done as below to preserve leading
+    #  zeroes which are needed to keep the code size exact
+    #
+    my $result ="";
+    foreach my $letter (@letters) {
+	$result.=$substitution{$letter};
+    }
+    return $result;
+}
+
+#  Determine if a code is a valid numeric code.  Valid
+#  numeric codes must be comprised entirely of digits and
+#  have a correct number of digits.
+#
+#  Parameters:
+#     value      - proposed code value.
+#     num_digits - Number of digits required.
+#
+sub is_valid_numeric_code {
+    my ($value, $num_digits) = @_;
+    #   Remove leading/trailing whitespace;
+    $value =~ s/^\s*//;
+    $value =~ s/\s*$//;
+    
+    #  All digits?
+    if ($value =~ /^[0-9]+$/) {
+	return "Numeric code $value has invalid characters - must only be digits";
+    }
+    if (length($value) != $num_digits) {
+	return "Numeric code $value incorrect number of digits (correct = $num_digits)";
+    }
+    return undef;
+}
+#   Determines if a code is a valid alhpa code.  Alpha codes
+#   are ciphers that map  [A-J,a-j] -> 0..9 0..9.
+#   They also have a correct digit count.
+# Parameters:
+#     value          - Proposed code value.
+#     num_letters    - correct number of letters.
+# Note:
+#    leading and trailing whitespace are ignored.
+#
+sub is_valid_alpha_code {
+    my ($value, $num_letters) = @_;
+    
+     # strip leading and trailing spaces.
+
+    $value =~ s/^\s*//g;
+    $value =~ s/\s*$//g;
+
+    #  All alphas in the right range?
+    if ($value !~ /^[A-J,a-j]+$/) {
+	return "Invalid letter code $value must only contain A-J";
+    }
+    if (length($value) != $num_letters) {
+	return "Letter code $value has incorrect number of letters (correct = $num_letters)";
+    }
+    return undef;
+}
+
+#   Determine if a code entered by the user in a helper is valid.
+#   valid depends on the code type and the type of code selected.
+#   The type of code selected can either be numeric or 
+#   Alphabetic.  If alphabetic, the code, in fact is a simple
+#   substitution cipher for the actual numeric code: 0->A, 1->B ...
+#   We'll be nice and be case insensitive for alpha codes.
+# Parameters:
+#    code_value    - the value of the code the user typed in.
+#    code_option   - The code type selected from the set in the scantron format
+#                    table.
+# Returns:
+#    undef         - The code is valid.
+#    other         - An error message indicating what's wrong.
+#
+sub is_code_valid {
+    my ($code_value, $code_option) = @_;
+    my ($code_type, $code_length) = ('letter', 6);	# defaults.
+    open(FG, $Apache::lonnet::perlvar{'lonTabDir'}.'/scantronformat.tab');
+    foreach my $line (<FG>) {
+	my ($name, $type, $length) = (split(/:/, $line))[0,2,4];
+	if($name eq $code_option) {
+	    $code_length = $length;
+	    if($type eq 'number') {
+		$code_type = 'number';
+	    }
+	}
+    }
+    my $valid;
+    if ($code_type eq 'number') {
+	return &is_valid_numeric_code($code_value, $code_length);
+    } else {
+	return &is_valid_alpha_code($code_value, $code_length);
+    }
+
+}
+
 #   Compare two students by name.  The students are in the form
 #   returned by the helper:
 #      user:domain:section:last,   first:status
@@ -998,13 +1116,15 @@ ENDPART
 		    if((($helper->{'VARS'}->{'ANSWER_TYPE'} eq 'no') ||
 		       ($helper->{'VARS'}->{'ANSWER_TYPE'} eq 'only')) && 
 		       ($urlp=~/\.(problem|exam|quiz|assess|survey|form|library|page)$/)) {
-			$form{'grade_target'}='answer';
-			$form{'answer_output_mode'}='tex';
-			$form{'rndseed'}=$rndseed;
-			$form{'problem_split'}=$parmhash{'problem_stream_switch'};
+			#  Don't permanently modify %$form...
+			my %answerform = %form;
+			$answerform{'grade_target'}='answer';
+			$answerform{'answer_output_mode'}='tex';
+			$answerform{'rndseed'}=$rndseed;
+			$answerform{'problem_split'}=$parmhash{'problem_stream_switch'};
                         if ($urlp=~/\/res\//) {$env{'request.state'}='published';}
 			$resources_printed .= $urlp.':';
-			my $answer=&Apache::lonnet::ssi($urlp,%form);
+			my $answer=&Apache::lonnet::ssi($urlp,%answerform);
 			if ($helper->{'VARS'}->{'ANSWER_TYPE'} eq 'no') {
 			    $texversion=~s/(\\keephidden{ENDOFPROBLEM})/$answer$1/;
 			} else {
@@ -1105,10 +1225,12 @@ ENDPART
 		my $current_counter=$env{'form.counter'};
 		if(($helper->{'VARS'}->{'ANSWER_TYPE'} eq 'no') ||
 		   ($helper->{'VARS'}->{'ANSWER_TYPE'} eq 'only')) {
-		    $form{'grade_target'}='answer';
-		    $form{'answer_output_mode'}='tex';
+		    #  Don't permanently pervert the %form hash
+		    my %answerform = %form;
+		    $answerform{'grade_target'}='answer';
+		    $answerform{'answer_output_mode'}='tex';
 		    $resources_printed .= $urlp.':';
-		    my $answer=&Apache::lonnet::ssi($urlp,%form);
+		    my $answer=&Apache::lonnet::ssi($urlp,%answerform);
 		    &Apache::lonnet::appenv(('form.counter' => $current_counter));
 		    if ($helper->{'VARS'}->{'ANSWER_TYPE'} eq 'no') {
 			$texversion=~s/(\\keephidden{ENDOFPROBLEM})/$answer$1/;
@@ -1240,23 +1362,51 @@ ENDPART
 	 my $num_todo=$helper->{'VARS'}->{'NUMBER_TO_PRINT_TOTAL'};
 	 my $code_name=$helper->{'VARS'}->{'ANON_CODE_STORAGE_NAME'};
 	 my $old_name=$helper->{'VARS'}->{'REUSE_OLD_CODES'};
+	 my $single_code = $helper->{'VARS'}->{'SINGLE_CODE'};
+	 my $code_option=$helper->{'VARS'}->{'CODE_OPTION'};
+	 open(FH,$Apache::lonnet::perlvar{'lonTabDir'}.'/scantronformat.tab');
+	 my ($code_type,$code_length)=('letter',6);
+	 foreach my $line (<FH>) {
+	     my ($name,$type,$length) = (split(/:/,$line))[0,2,4];
+	     if ($name eq $code_option) {
+		 $code_length=$length;
+		 if ($type eq 'number') { $code_type = 'number'; }
+	     }
+	 }
 	 my %moreenv = ('textwidth' => &get_textwidth($helper,$LaTeXwidth));
 	 $moreenv{'problem_split'}    = $parmhash{'problem_stream_switch'};
 	 my $seed=time+($$<<16)+($$);
 	 my @allcodes;
 	 if ($old_name) {
-	     my %result=&Apache::lonnet::get('CODEs',[$old_name],$cdom,$cnum);
+	     my %result=&Apache::lonnet::get('CODEs',
+					     [$old_name,"type\0$old_name"],
+					     $cdom,$cnum);
+	     $code_type=$result{"type\0$old_name"};
 	     @allcodes=split(',',$result{$old_name});
 	     $num_todo=scalar(@allcodes);
+	 } elsif ($single_code) {
+
+	     # If an alpha code have to convert to numbers so it can be
+	     # converted back to letters again :-)
+	     #
+	     if ($code_type ne 'number') {
+		 $single_code = &letters_to_num($single_code);
+		 $num_todo    = 1;
+	     }
+	     @allcodes = ($single_code);
 	 } else {
 	     my %allcodes;
 	     srand($seed);
 	     for (my $i=0;$i<$num_todo;$i++) {
-		 $moreenv{'CODE'}=&get_CODE(\%allcodes,$i,$seed,'6');
+		 $moreenv{'CODE'}=&get_CODE(\%allcodes,$i,$seed,$code_length,
+					    $code_type);
 	     }
 	     if ($code_name) {
 		 &Apache::lonnet::put('CODEs',
-				      {$code_name =>join(',',keys(%allcodes))},
+				      {
+					$code_name =>join(',',keys(%allcodes)),
+					"type\0$code_name" => $code_type
+				      },
 				      $cdom,$cnum);
 	     }
 	     @allcodes=keys(%allcodes);
@@ -1272,7 +1422,11 @@ ENDPART
 	 my $count=0;
 	 foreach my $code (sort(@allcodes)) {
 	     my $file_num=int($count/$number_per_page);
-	     $moreenv{'CODE'}=&num_to_letters($code);
+	     if ($code_type eq 'number') { 
+		 $moreenv{'CODE'}=$code;
+	     } else {
+		 $moreenv{'CODE'}=&num_to_letters($code);
+	     }
 	     my ($output,$fullname, $printed)=
 		 &print_resources($r,$helper,'anonymous',$type,\%moreenv,
 				  \@master_seq,$flag_latex_header_remove,
@@ -1312,12 +1466,14 @@ ENDPART
 		my $texversion=&Apache::lonnet::ssi($urlp,%form);
 		if(($helper->{'VARS'}->{'ANSWER_TYPE'} eq 'no') ||
 		   ($helper->{'VARS'}->{'ANSWER_TYPE'} eq 'only')) {
-		    $form{'grade_target'}='answer';
-		    $form{'answer_output_mode'}='tex';
-		    $form{'latex_type'}=$helper->{'VARS'}->{'LATEX_TYPE'};
-		    $form{'rndseed'}=$rndseed;
+		    #  Don't permanently pervert %form:
+		    my %answerform = %form;
+		    $answerform{'grade_target'}='answer';
+		    $answerform{'answer_output_mode'}='tex';
+		    $answerform{'latex_type'}=$helper->{'VARS'}->{'LATEX_TYPE'};
+		    $answerform{'rndseed'}=$rndseed;
 		    $resources_printed .= $urlp.':';
-		    my $answer=&Apache::lonnet::ssi($urlp,%form);
+		    my $answer=&Apache::lonnet::ssi($urlp,%answerform);
 		    if ($helper->{'VARS'}->{'ANSWER_TYPE'} eq 'no') {
 			$texversion=~s/(\\keephidden{ENDOFPROBLEM})/$answer$1/;
 		    } else {
@@ -1463,24 +1619,20 @@ $r->print(<<FINALEND);
 FINALEND
 }
 
-sub num_to_letters {
-    my ($num) = @_;
-    my @nums= split('',$num);
-    my @num_to_let=('A'..'Z');
-    my $word;
-    foreach my $digit (@nums) { $word.=$num_to_let[$digit]; }
-    return $word;
-}
 
 sub get_CODE {
-    my ($all_codes,$num,$seed,$size)=@_;
+    my ($all_codes,$num,$seed,$size,$type)=@_;
     my $max='1'.'0'x$size;
     my $newcode;
     while(1) {
 	$newcode=sprintf("%06d",int(rand($max)));
 	if (!exists($$all_codes{$newcode})) {
 	    $$all_codes{$newcode}=1;
-	    return &num_to_letters($newcode);
+	    if ($type eq 'number' ) {
+		return $newcode;
+	    } else {
+		return &num_to_letters($newcode);
+	    }
 	}
     }
 }
@@ -1527,9 +1679,11 @@ sub print_resources {
 		    my $current_counter=$env{'form.counter'};
 		    if(($helper->{'VARS'}->{'ANSWER_TYPE'} eq 'no') ||
 		       ($helper->{'VARS'}->{'ANSWER_TYPE'} eq 'only')) {
-			$moreenv->{'answer_output_mode'}='tex';
-			$moreenv->{'latex_type'}=$helper->{'VARS'}->{'LATEX_TYPE'};
-			my $ansrendered = &Apache::loncommon::get_student_answers($curresline,$username,$userdomain,$env{'request.course.id'},%{$moreenv});
+			#   Use a copy of the hash so we don't pervert it on future loop passes.
+			my %answerenv = %{$moreenv};
+			$answerenv{'answer_output_mode'}='tex';
+			$answerenv{'latex_type'}=$helper->{'VARS'}->{'LATEX_TYPE'};
+			my $ansrendered = &Apache::loncommon::get_student_answers($curresline,$username,$userdomain,$env{'request.course.id'},%answerenv);
 			&Apache::lonnet::appenv(('form.counter' => $current_counter));
 			if ($helper->{'VARS'}->{'ANSWER_TYPE'} eq 'no') {
 			    $rendered=~s/(\\keephidden{ENDOFPROBLEM})/$ansrendered$1/;
@@ -1931,8 +2085,22 @@ CHOOSE_STUDENTS
 	my $namechoice='<choice></choice>';
 	foreach my $name (sort {uc($a) cmp uc($b)} @names) {
 	    if ($name =~ /^error: 2 /) { next; }
+	    if ($name =~ /^type\0/) { next; }
 	    $namechoice.='<choice computer="'.$name.'">'.$name.'</choice>';
 	}
+	open(FH,$Apache::lonnet::perlvar{'lonTabDir'}.'/scantronformat.tab');
+	my $codechoice='';
+	foreach my $line (<FH>) {
+	    my ($name,$description,$code_type,$code_length)=
+		(split(/:/,$line))[0,1,2,4];
+	    if ($code_length > 0 && 
+		$code_type =~/^(letter|number|-1)/) {
+		$codechoice.='<choice computer="'.$name.'">'.$description.'</choice>';
+	    }
+	}
+	if ($codechoice eq '') {
+	    $codechoice='<choice computer="default">Default</choice>';
+	}
         &Apache::lonxml::xmlparse($r, 'helper', <<CHOOSE_ANON1);
   <state name="CHOOSE_ANON1" title="Select Students and Resources">
     <nextstate>PAGESIZE</nextstate>
@@ -1941,16 +2109,36 @@ CHOOSE_STUDENTS
     <string variable="NUMBER_TO_PRINT_TOTAL" maxlength="5" size="5">
        <validator>
 	if (((\$helper->{'VARS'}{'NUMBER_TO_PRINT_TOTAL'}+0) < 1) &&
-	    !\$helper->{'VARS'}{'REUSE_OLD_CODES'}) {
+	    !\$helper->{'VARS'}{'REUSE_OLD_CODES'}                &&
+            !\$helper->{'VARS'}{'SINGLE_CODE'}) {
 	    return "You need to specify the number of assignments to print";
 	}
 	return undef;
        </validator>
     </string>
     <message></td></tr><tr><td></message>
+    <message><b>Value of CODE to print?</b></td><td></message>
+    <string variable="SINGLE_CODE" size="10" defaultvalue="zzzz">
+        <validator>
+	   if(!\$helper->{'VARS'}{'NUMBER_TO_PRINT_TOTAL'}           &&
+	      !\$helper->{'VARS'}{'REUSE_OLD_CODES'}) {
+	      return &Apache::lonprintout::is_code_valid(\$helper->{'VARS'}{'SINGLE_CODE'},
+						      \$helper->{'VARS'}{'CODE_OPTION'});
+	   } else {
+	       return undef;	# Other forces control us.
+	   }
+        </validator>
+    </string>
+    <message></td></tr><tr><td></message>
     <message><b>Names to store the CODEs under for later:</b></message>
     <message></td><td></message>
     <string variable="ANON_CODE_STORAGE_NAME" maxlength="50" size="20" />
+    <message></td></tr><tr><td></message>
+    <message><b>Bubble sheet type:</b></message>
+    <message></td><td></message>
+    <dropdown variable="CODE_OPTION" multichoice="0" allowempty="0">
+    $codechoice
+    </dropdown>
     <message></td></tr></table></message>
     <message><hr width='33%' /></message>
     <message><b>Reprint a set of saved CODEs:</b></message>
@@ -2008,16 +2196,36 @@ CHOOSE_STUDENTS1
     <string variable="NUMBER_TO_PRINT_TOTAL" maxlength="5" size="5">
        <validator>
 	if (((\$helper->{'VARS'}{'NUMBER_TO_PRINT_TOTAL'}+0) < 1) &&
-	    !\$helper->{'VARS'}{'REUSE_OLD_CODES'}) {
+	    !\$helper->{'VARS'}{'REUSE_OLD_CODES'}                &&
+	    !\$helper->{'VARS'}{'SINGLE_CODE'}) {
 	    return "You need to specify the number of assignments to print";
 	}
 	return undef;
        </validator>
     </string>
     <message></td></tr><tr><td></message>
+    <message><b>Value of CODE to print?</b></td><td></message>
+    <string variable="SINGLE_CODE" size="10" defaultvalue="zzzz">
+        <validator>
+	   if(!\$helper->{'VARS'}{'NUMBER_TO_PRINT_TOTAL'}           &&
+	      !\$helper->{'VARS'}{'REUSE_OLD_CODES'}) {
+	      return &Apache::lonprintout::is_code_valid(\$helper->{'VARS'}{'SINGLE_CODE'},
+						      \$helper->{'VARS'}{'CODE_OPTION'});
+	   } else {
+	       return undef;	# Other forces control us.
+	   }
+        </validator>
+    </string>
+    <message></td></tr><tr><td></message>
     <message><b>Names to store the CODEs under for later:</b></message>
     <message></td><td></message>
     <string variable="ANON_CODE_STORAGE_NAME" maxlength="50" size="20" />
+    <message></td></tr><tr><td></message>
+    <message><b>Bubble sheet type:</b></message>
+    <message></td><td></message>
+    <dropdown variable="CODE_OPTION" multichoice="0" allowempty="0">
+    $codechoice
+    </dropdown>
     <message></td></tr></table></message>
     <message><hr width='33%' /></message>
     <message><b>Reprint a set of saved CODEs:</b></message>