--- loncom/interface/lonnavmaps.pm	2002/10/29 20:26:03	1.93
+++ loncom/interface/lonnavmaps.pm	2002/11/03 21:05:03	1.97
@@ -2,7 +2,7 @@
 # The LearningOnline Network with CAPA
 # Navigate Maps Handler
 #
-# $Id: lonnavmaps.pm,v 1.93 2002/10/29 20:26:03 bowersj2 Exp $
+# $Id: lonnavmaps.pm,v 1.97 2002/11/03 21:05:03 bowersj2 Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -837,19 +837,37 @@ sub new_handle {
                                           ''));
     $r->print('<script>window.focus();</script>');
     my $desc=$ENV{'course.'.$ENV{'request.course.id'}.'.description'};
-    if (defined($desc)) { $r->print("<h2>$desc</h2>\n"); }
+    $r->print('<table border="0" cellpadding="2" cellspacing="0">');
     my $date=localtime;
-    $r->print("<h3>$date</h3>\n");
-    $r->rflush();
+    $r->print('<tr><td align="right" valign="bottom">Key:&nbsp;&nbsp;</td>');
     if ($navmap->{LAST_CHECK}) {
-        $r->print('<img src="/adm/lonMisc/chat.gif"> New discussion since '.
+        $r->print('<td align="center" valign="bottom">&nbsp;&nbsp;'.
+                  '<img src="/adm/lonMisc/chat.gif"> New discussion since '.
                   strftime("%A, %b %e at %I:%M %P", localtime($navmap->{LAST_CHECK})).
-                  '<br><img src="/adm/lonMisc/feedback.gif"> New message (click to open)<p>'); 
+                  '</td><td align="center" valign="bottom">&nbsp;&nbsp;'.
+                  '<img src="/adm/lonMisc/feedback.gif"> New message (click to open)<p>'.
+                  '</td>'); 
     } else {
-        $r->print('<img src="/adm/lonMisc/chat.gif"> Discussions'.
-                  '<br><img src="/adm/lonMisc/feedback.gif"> New message (click to open)<p>'); 
+        $r->print('<td align="center" valign="bottom">&nbsp;&nbsp;'.
+                  '<img src="/adm/lonMisc/chat.gif"> Discussions</td><td align="center" valign="bottom">'.
+                  '&nbsp;&nbsp;<img src="/adm/lonMisc/feedback.gif"> New message (click to open)'.
+                  '</td>'); 
+    }
+    $r->print('</tr></table>');
+    my $condition = 0;
+    if ($ENV{'form.condition'}) {
+        $condition = 1;
     }
 
+    if ($condition) {
+        $r->print('<a href="navmaps?condition=0&filter=">Close All Folders</a>');
+    } else {
+        $r->print('<a href="navmaps?condition=1&filter=">Open All Folders</a>');
+    }
+
+    $r->print('<br>&nbsp;');
+    $r->rflush();
+
     # Now that we've displayed some stuff to the user, init the navmap
     $navmap->init();
 
@@ -929,17 +947,6 @@ sub new_handle {
     my $queryAdd = "postdata=" . &Apache::lonnet::escape($currenturl) .
         "&alreadyHere=1";
 
-    my $condition = 0;
-    if ($ENV{'form.condition'}) {
-        $condition = 1;
-    }
-
-    if ($condition) {
-        $r->print('<a href="navmaps?condition=0&filter=">Close All Folders</a><br /><br />');
-    } else {
-        $r->print('<a href="navmaps?condition=1&filter=">Open All Folders</a><br /><br />');
-    }
-
     # Begin the HTML table
     # four cols: resource + indent, chat+feedback, icon, text string
     $r->print('<table cellspacing="0" cellpadding="3" border="0" bgcolor="#FFFFFF">' ."\n");
@@ -950,6 +957,10 @@ sub new_handle {
     # Here's a simple example of the iterator.
     # Preprocess the map: Look for current URL, force inlined maps to display
 
+    # This currently does very little...
+    my $mapEventualIterator = Apache::lonnavmaps::iterator->new($navmap, undef, undef, {},
+                                                                undef, $condition);
+
     my $mapIterator = $navmap->getIterator(undef, undef, {}, 1);
     my $found = 0;
     my $depth = 1;
@@ -961,12 +972,8 @@ sub new_handle {
     my $counter = 0;
     
     while ($depth > 0) {
-        if ($curRes == $mapIterator->BEGIN_MAP()) {
-            $depth++;
-        }
-        if ($curRes == $mapIterator->END_MAP()) {
-            $depth--;
-        }
+        if ($curRes == $mapIterator->BEGIN_MAP()) { $depth++; }
+        if ($curRes == $mapIterator->END_MAP()) { $depth--; }
 
         if (ref($curRes)) { $counter++; }
 
@@ -1051,12 +1058,8 @@ sub new_handle {
         if ($curRes == $mapIterator->BEGIN_BRANCH()) {
             $isNewBranch = 1;
         }
-        if ($curRes == $mapIterator->BEGIN_MAP()) {
-            $depth++;
-        }
-        if ($curRes == $mapIterator->END_MAP()) {
-            $depth--;
-        }
+        if ($curRes == $mapIterator->BEGIN_MAP()) { $depth++; }
+        if ($curRes == $mapIterator->END_MAP()) { $depth--; }
 
         if (ref($curRes)) { $counter++; }
 
@@ -1287,6 +1290,9 @@ sub new_handle {
                 }
 
                 $r->print("  $curMarkerBegin<a href=\"$link\">$title$partLabel</a> $curMarkerEnd $nonLinkedText");
+                $r->print(" TDV:" . $curRes->{DATA}->{TOP_DOWN_VAL}); # temp
+                $r->print(" BUV:" . $curRes->{DATA}->{BOT_UP_VAL}); # temp
+                $r->print(" DD:" . $curRes->{DATA}->{DISPLAY_DEPTH}); # temp
 
                 if ($curRes->{RESOURCE_ERROR}) {
                     $r->print(&Apache::loncommon::help_open_topic ("Navmap_Host_Down",
@@ -1769,7 +1775,7 @@ sub courseMapDefined {
 
 sub getIterator {
     my $self = shift;
-    my $iterator = Apache::lonnavmaps::iterator->new($self, shift, shift,
+    my $iterator = Apache::lonnavmaps::DFSiterator->new($self, shift, shift,
                                                      shift, undef, shift, 
                                                      $ENV{'form.direction'});
     return $iterator;
@@ -2028,6 +2034,135 @@ sub END_BRANCH { return 4; }   # end of
 sub FORWARD { return 1; }      # go forward
 sub BACKWARD { return 2; }
 
+sub min {
+    (my $a, my $b) = @_;
+    if ($a < $b) { return $a; } else { return $b; }
+}
+
+sub new {
+    # magic invocation to create a class instance
+    my $proto = shift;
+    my $class = ref($proto) || $proto;
+    my $self = {};
+
+    $self->{NAV_MAP} = shift;
+    return undef unless ($self->{NAV_MAP});
+
+    # Handle the parameters
+    $self->{FIRST_RESOURCE} = shift || $self->{NAV_MAP}->firstResource();
+    $self->{FINISH_RESOURCE} = shift || $self->{NAV_MAP}->finishResource();
+
+    # If the given resources are just the ID of the resource, get the
+    # objects
+    if (!ref($self->{FIRST_RESOURCE})) { $self->{FIRST_RESOURCE} = 
+             $self->{NAV_MAP}->getById($self->{FIRST_RESOURCE}); }
+    if (!ref($self->{FINISH_RESOURCE})) { $self->{FINISH_RESOURCE} = 
+             $self->{NAV_MAP}->getById($self->{FINISH_RESOURCE}); }
+
+    $self->{FILTER} = shift;
+
+    # A hash, used as a set, of resource already seen
+    $self->{ALREADY_SEEN} = shift;
+    if (!defined($self->{ALREADY_SEEN})) { $self->{ALREADY_SEEN} = {} };
+    $self->{CONDITION} = shift;
+
+    # Now, we need to pre-process the map, by walking forward and backward
+    # over the parts of the map we're going to look at.
+
+    # The processing steps are exactly the same, except for a few small 
+    # changes, so I bundle those up in the following list of two elements:
+    # (direction_to_iterate, VAL_name, next_resource_method_to_call,
+    # first_resource).
+    # This prevents writing nearly-identical code twice.
+    my @iterations = ( [FORWARD(), 'TOP_DOWN_VAL', 'getNext', 
+                        'FIRST_RESOURCE'],
+                       [BACKWARD(), 'BOT_UP_VAL', 'getPrevious', 
+                        'FINISH_RESOURCE'] );
+
+    foreach my $pass (@iterations) {
+        my $direction = $pass->[0];
+        my $valName = $pass->[1];
+        my $nextResourceMethod = $pass->[2];
+        my $firstResourceName = $pass->[3];
+
+        my $iterator = Apache::lonnavmaps::DFSiterator->new($self->{NAV_MAP}, 
+                                                            $self->{FIRST_RESOURCE},
+                                                            $self->{FINISH_RESOURCE},
+                                                            {}, undef, 0, $direction);
+    
+        # prime the recursion
+        $self->{$firstResourceName}->{DATA}->{$valName} = 0;
+        my $depth = 1;
+        $iterator->next();
+        my $curRes = $iterator->next();
+        while ($depth > 0) {
+            if ($curRes == $iterator->BEGIN_MAP()) { $depth++; }
+            if ($curRes == $iterator->END_MAP()) { $depth--; }
+        
+            if (ref($curRes)) {
+                my $resultingVal = $curRes->{DATA}->{$valName};
+                my $nextResources = $curRes->$nextResourceMethod();
+                my $resourceCount = scalar(@{$nextResources});
+            
+                if ($resourceCount == 1) {
+                    my $current = $nextResources->[0]->{DATA}->{$valName} || 999999999;
+                    $nextResources->[0]->{DATA}->{$valName} = min($resultingVal, $current);
+                }
+                
+                if ($resourceCount > 1) {
+                    foreach my $res (@{$nextResources}) {
+                        my $current = $res->{DATA}->{$valName} || 999999999;
+                        $res->{DATA}->{$valName} = min($current, $resultingVal + 1);
+                    }
+                }
+            }
+            if (ref($curRes) && $curRes->is_map() && $direction == FORWARD()) {
+                my $firstResource = $curRes->map_start();
+                my $finishResource = $curRes->map_finish();
+                my $newIterator = Apache::lonnavmaps::iterator->new($self->{NAV_MAP},
+                                                                    $firstResource,
+                                                                    $finishResource,
+                                                                    $self->{FILTER},
+                                                                    $self->{ALREADY_SEEN},
+                                                                    $self->{CONDITION});
+            }
+            
+            # Assign the final val
+            if (ref($curRes) && $direction == BACKWARD()) {
+                $curRes->{DATA}->{DISPLAY_DEPTH} = min($curRes->{DATA}->{TOP_DOWN_VAL},
+                                                       $curRes->{DATA}->{BOT_UP_VAL});
+            }
+            $curRes = $iterator->next();
+        }
+    }
+
+    # Now we're ready to start iterating.
+}
+
+1;
+
+package Apache::lonnavmaps::DFSiterator;
+
+# UNDOCUMENTED: This is a private library, it should not generally be used
+# by the outside world. What it does is walk through the nav map in a 
+# depth-first fashion. This is not appropriate for most uses, but it is
+# used by the main iterator for pre-processing. It also is able to isolate
+# much of the complexity of the main iterator, so the main iterator is much
+# simpler.
+# There is no real benefit in merging the main iterator and this one into one class...
+# all the logic in DFSiterator would need to be replicated, you gain no performance,
+# at best, you just make one massively complicated iterator in place of two 
+# somewhat complicated ones. ;-) - Jeremy
+
+# Here are the tokens for the iterator, replicated from iterator for convenience:
+
+sub BEGIN_MAP { return 1; }    # begining of a new map
+sub END_MAP { return 2; }      # end of the map
+sub BEGIN_BRANCH { return 3; } # beginning of a branch
+sub END_BRANCH { return 4; }   # end of a branch
+sub FORWARD { return 1; }      # go forward
+sub BACKWARD { return 2; }
+
 # Params: nav map, start resource, end resource, filter, condition, 
 # already seen hash ref
 
@@ -2236,7 +2371,7 @@ sub next {
         my $finishResource = $self->{HERE}->map_finish();
 
         $self->{RECURSIVE_ITERATOR} =
-          Apache::lonnavmaps::iterator->new ($self->{NAV_MAP}, $firstResource, 
+          Apache::lonnavmaps::DFSiterator->new ($self->{NAV_MAP}, $firstResource, 
                      $finishResource, $self->{FILTER}, $self->{ALREADY_SEEN},
                                              $self->{CONDITION}, $self->{DIRECTION});
     }