--- rat/lonpageflip.pm	2000/10/17 14:23:32	1.9
+++ rat/lonpageflip.pm	2001/11/29 19:23:49	1.18
@@ -2,6 +2,30 @@
 #
 # Page flip handler
 #
+# $Id: lonpageflip.pm,v 1.18 2001/11/29 19:23:49 www 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/
+#
 # (Page Handler
 #
 # (TeX Content Handler
@@ -10,7 +34,9 @@
 # 08/30,08/31,09/06,09/14,09/15,09/16,09/19,09/20,09/21,09/23,
 # 10/02 Gerd Kortemeyer)
 #
-# 10/03,10/05,10/06,10/07,10/09,10/10,10/11,10/16,10/17 Gerd Kortemeyer
+# 10/03,10/05,10/06,10/07,10/09,10/10,10/11,10/16,10/17,
+# 11/14,11/16,
+# 10/01/01,05/01,05/28,07/05 Gerd Kortemeyer
 
 package Apache::lonpageflip;
 
@@ -37,6 +63,80 @@ sub addrid {
     return $current;
 }
 
+sub move {
+    my ($rid,$mapurl,$direction)=@_;
+
+    my $next='';
+
+              my $mincond=1;
+              my $posnext='';
+              if ($direction eq 'forward') {
+# --------------------------------------------------------------------- Forward
+                  if ($hash{'type_'.$rid} eq 'finish') {
+	             $rid=$hash{'ids_/res/'.$mapurl}; 
+                  }
+                  map {
+                      my $thiscond=
+      &Apache::lonnet::directcondval($hash{'condid_'.$hash{'undercond_'.$_}});
+                      if ($thiscond>=$mincond) {
+		          if ($posnext) {
+		             $posnext.=','.$_.':'.$thiscond;
+                          } else {
+                             $posnext=$_.':'.$thiscond;
+		          }
+                          if ($thiscond>$mincond) { $mincond=$thiscond; }
+	              }
+                  } split(/\,/,$hash{'to_'.$rid});
+                  map {
+                      my ($linkid,$condval)=split(/\:/,$_);
+                      if ($condval>=$mincond) {
+		          $next=&addrid($next,$hash{'goesto_'.$linkid},
+                                $hash{'condid_'.$hash{'undercond_'.$linkid}});
+                      }
+                  } split(/\,/,$posnext);
+                  if ($hash{'is_map_'.$next}) {
+                      if (
+      $hash{'map_type_'.$hash{'map_pc_'.$hash{'src_'.$next}}} eq 'sequence') {
+			  $mapurl=$hash{'src_'.$next};
+			  $next=$hash{'map_start_'.$hash{'src_'.$next}};
+                     }
+                  }
+              } elsif ($direction eq 'back') {
+# ------------------------------------------------------------------- Backwards
+                  if ($hash{'type_'.$rid} eq 'start') {
+	             $rid=$hash{'ids_/res/'.$mapurl};
+                  }
+                  map {
+                      my $thiscond=
+      &Apache::lonnet::directcondval($hash{'condid_'.$hash{'undercond_'.$_}});
+                      if ($thiscond>=$mincond) {
+		          if ($posnext) {
+		             $posnext.=','.$_.':'.$thiscond;
+                          } else {
+                             $posnext=$_.':'.$thiscond;
+		          }
+                          if ($thiscond>$mincond) { $mincond=$thiscond; }
+	              }
+                  } split(/\,/,$hash{'from_'.$rid});
+                  map {
+                      my ($linkid,$condval)=split(/\:/,$_);
+                      if ($condval>=$mincond) {
+		          $next=&addrid($next,$hash{'comesfrom_'.$linkid},
+                                $hash{'condid_'.$hash{'undercond_'.$linkid}});
+                      }
+                  } split(/\,/,$posnext);
+                  if ($hash{'is_map_'.$next}) {
+                      if (
+      $hash{'map_type_'.$hash{'map_pc_'.$hash{'src_'.$next}}} eq 'sequence') {
+			  $mapurl=$hash{'src_'.$next};
+			  $next=$hash{'map_finish_'.$hash{'src_'.$next}};
+                     }
+                  }
+	      }
+
+              return ($next,$mapurl);
+}
+
 # ================================================================ Main Handler
 
 sub handler {
@@ -61,9 +161,30 @@ sub handler {
       $ENV{'form.postdata'}=~/(\w+)\:(.*)/;
       my $direction=$1;
       my $currenturl=$2;
+      if ($direction eq 'return') {
+# -------------------------------------------------------- Return to last known
+         my $last;
+         if (tie(%hash,'GDBM_File',$ENV{'request.course.fn'}.'_symb.db',
+                    &GDBM_READER,0640)) {
+	     $last=$hash{'last_known'};
+             untie(%hash);
+         }
+         my $newloc;
+         if ($last) {
+            $newloc='/res/'.(split(/\_\_\_/,$last))[1];
+         } else {
+	    $newloc='/adm/noidea.html';
+         }  
+	 $r->content_type('text/html');
+         $r->header_out(Location => 
+			'http://'.$ENV{'HTTP_HOST'}.$newloc);
+                               
+         return REDIRECT;
+      }
       $currenturl=~s/^http\:\/\///;
       $currenturl=~s/^[^\/]+//;
-      unless ($currenturl=~/\/res\//) {
+      unless (($currenturl=~/^\/res\//) || 
+              ($currenturl=~/^\/adm\/wrapper\//))  {
 	 my $last;
          if (tie(%hash,'GDBM_File',$ENV{'request.course.fn'}.'_symb.db',
                     &GDBM_READER,0640)) {
@@ -89,55 +210,16 @@ sub handler {
           if (tie(%hash,'GDBM_File',$ENV{'request.course.fn'}.'.db',
                         &GDBM_READER,0640)) {
               my $rid=$hash{'map_pc_/res/'.$mapurl}.'.'.$mapnum;
-              my $next='';
-              my $mincond=1;
-              my $posnext='';
-              if ($direction eq 'forward') {
-# --------------------------------------------------------------------- Forward
-                  map {
-                      my $thiscond=
-      &Apache::lonnet::directcondval($hash{'condid_'.$hash{'undercond_'.$_}});
-                      if ($thiscond>=$mincond) {
-		          if ($posnext) {
-		             $posnext.=','.$_.':'.$thiscond;
-                          } else {
-                             $posnext=$_.':'.$thiscond;
-		          }
-                          if ($thiscond>$mincond) { $mincond=$thiscond; }
-	              }
-                  } split(/\,/,$hash{'to_'.$rid});
-                  map {
-                      my ($linkid,$condval)=split(/\:/,$_);
-                      if ($condval>=$mincond) {
-		          $next=&addrid($next,$hash{'goesto_'.$linkid},
-                                $hash{'condid_'.$hash{'undercond_'.$linkid}});
-                      }
-                  } split(/\,/,$posnext);
-              } elsif ($direction eq 'back') {
-# ------------------------------------------------------------------- Backwards
-                  map {
-                      my $thiscond=
-      &Apache::lonnet::directcondval($hash{'condid_'.$hash{'undercond_'.$_}});
-                      if ($thiscond>=$mincond) {
-		          if ($posnext) {
-		             $posnext.=','.$_.':'.$thiscond;
-                          } else {
-                             $posnext=$_.':'.$thiscond;
-		          }
-                          if ($thiscond>$mincond) { $mincond=$thiscond; }
-	              }
-                  } split(/\,/,$hash{'from_'.$rid});
-                  map {
-                      my ($linkid,$condval)=split(/\:/,$_);
-                      if ($condval>=$mincond) {
-		          $next=&addrid($next,$hash{'comesfrom_'.$linkid},
-                                $hash{'condid_'.$hash{'undercond_'.$linkid}});
-                      }
-                  } split(/\,/,$posnext);
- 	      } elsif ($direction eq 'up') {
-# -------------------------------------------------------------------------- Up
-              } elsif ($direction eq 'down') {
-# ------------------------------------------------------------------------ Down
+
+# ------------------------------------------------- Move forward, backward, etc
+
+              ($next,$mapurl)=&move($rid,$mapurl,$direction);
+# -------------------------------------- Do we have one and only one empty URL?
+              my $safecount=0;
+              while (($next) && ($next!~/\,/) && (!$hash{'src_'.$next})
+                     && ($safecount<25)) {
+                  ($next,$mapurl)=&move($next,$mapurl,$direction);
+                  $safecount++;
               }
 # ----------------------------------------------------- Check out possibilities
               if ($next) {
@@ -209,9 +291,10 @@ ENDSTART
                      $r->print(<<ENDNONE);
 <head><title>Choose Next Location</title></head>
 <body bgcolor="#FFFFFF">
-<img src="/adm/lonKaputt/lonlogo_broken.gif" align=left>
+<img src="/adm/lonIcons/lonlogos.gif" align=right>
 <h1>Sorry!</h1>
 <h2>Next resource could not be identified.</h2>
+<h3>You probably are at the beginning or the end of the course.</h3>
 </body>
 </html>
 ENDNONE