--- rat/lonambiguous.pm	2000/10/12 02:14:01	1.1
+++ rat/lonambiguous.pm	2000/10/12 14:54:08	1.2
@@ -5,7 +5,7 @@
 #
 # 05/29/00,05/30,10/11 Gerd Kortemeyer)
 #
-# 10/11 Gerd Kortemeyer
+# 10/11,10/12 Gerd Kortemeyer
 
 package Apache::lonambiguous;
 
@@ -18,11 +18,13 @@ use GDBM_File;
 # ----------------------------------------------------------- Could not resolve
 
 sub getlost {
-    my $r=shift;
+    my ($r,$errmsg)=@_;
     $r->content_type('text/html');
     $r->send_http_header;
-    $r->print('<head><title>Unknown Error</title><body bgcolor="#FFFFFF">'.
- '<h1>LON-CAPA</h1>Could not handle ambiguous file reference.</body></html>');
+    $r->print(
+ '<head><title>Unknown Error</title></head><body bgcolor="#FFFFFF"><h1>'.
+ 'LON-CAPA</h1>Could not handle ambiguous resource reference.<p>'.$errmsg.
+ '</body></html>');
 }
 
 # ================================================================ Main Handler
@@ -36,11 +38,39 @@ sub handler {
       return OK;
    }
 
+# ---------------------------------------------------------- Is this selecting?
+   
+   my %bighash;
+
+   if ($ENV{'form.selecturl'}) {
+       my $envkey;
+       if (tie(%bighash,'GDBM_File',$ENV{'request.course.fn'}.'.db',
+                    &GDBM_READER,0640)) {
+          foreach $envkey (keys %ENV) {
+             if ($envkey=~/^form\.(\d+)\.(\d+)$/) {
+	         my $mapid=$1;
+                 my $resid=$2;
+                 my $resurl=$bighash{'src_'.$mapid.'.'.$resid};
+                 &Apache::lonnet::symblist($bighash{'map_id_'.$mapid},
+				           $resurl => $resid);
+                 $r->header_out(Location => 
+                                'http://'.$ENV{'HTTP_HOST'}.$resurl);
+                 return REDIRECT;
+             }
+	  }
+          untie(%bighash);
+# ---------------------------------------------------- Update symb and redirect
+       } else {
+          &getlost($r,'Could not access course structure.');
+          return OK;
+       }
+   }
+
 # ---------------------------------------------------------- Do we have a case?
 
    my $thisfn;
    unless (($thisfn=$ENV{'request.ambiguous'})&&($ENV{'request.course.fn'})) {
-       getlost($r);
+       &getlost($r,'Could not find information on resource.');
        return OK;
    }
       
@@ -48,7 +78,6 @@ sub handler {
 
     $thisfn=&Apache::lonnet::declutter($thisfn);
     my %hash;
-    my %bighash;
     my $syval='';
     
     if (tie(%hash,'GDBM_File',$ENV{'request.course.fn'}.'_symb.db',
@@ -56,8 +85,11 @@ sub handler {
        $syval=$hash{$thisfn};
        untie(%hash);
     }
+
 # ---------------------------------------------------------- There was an entry
+
     if ($syval) {
+
        if ($syval=~/\_$/) {
 # ----------------------------------- Okay, this should have appeared on a page
 	   $syval=~s/\_\_\_$//;
@@ -67,7 +99,7 @@ sub handler {
            return REDIRECT;
        } else {
 #  There is not really a problem (???), but cannot go back without endless loop
-           getlost($r);
+           &getlost($r,'The nature of the problem is unclear');
            return OK;
        }
     }
@@ -83,7 +115,7 @@ sub handler {
          my @possibilities=split(/\,/,$ids);
          my $couldbe='';
          map {
-             if (&allowed('bre',$bighash{'src_'.$_})) {
+             if (&Apache::lonnet::allowed('bre',$bighash{'src_'.$_})) {
 	         if ($couldbe) {
 		     $couldbe.=','.$_;
                  } else {
@@ -97,9 +129,31 @@ sub handler {
 # ----------------------------------------------- Okay, really multiple choices
                $r->content_type('text/html');
                $r->send_http_header;
-               $r->print(
-                '<head><title>Choose Location</title><body bgcolor="#FFFFFF">'.
-                '<h1>LON-CAPA</h1>Cool.</body></html>');
+               $r->print(<<ENDSTART);
+<head><title>Choose Location</title></head>
+<body bgcolor="#FFFFFF">
+<h1>LON-CAPA</h1>
+The resource you had been accessing appears more than once in this course,
+and LON-CAPA has insufficient session information to determine which instance
+of the resource you meant.
+<p>
+Please click on the instance of the resource you intended to access:
+<p>
+<form action="/adm/ambiguous" method=post>
+<input type=hidden name=orgurl value="$thisfn">
+<input type=hidden name=selecturl value=1>
+<table border=2>
+<tr><th>&nbsp;</th><th>Title</th><th>Type</th><th>Part of ...</th></tr>
+ENDSTART
+               map {
+                   my $mapurl=$bighash{'map_id_'.(split(/\./,$_))[0]};
+                   $r->print('<tr><td><input type=submit value=Select name="'.
+                              $_.'"></td><td>'.$bighash{'title_'.$_}.
+                              '</td><td>'.$bighash{'type_'.$_}.
+                              '</td><td><a href="'.$mapurl.'">'.$mapurl.
+			      '</a></td></tr>');
+               } @possibilities;
+               $r->print('</table></form></body></html>');
 	       untie(%bighash);
                return OK;
             }
@@ -109,7 +163,7 @@ sub handler {
   }
 
 # ------------------------------------ This handler should not have been called
-   getlost($r);
+   &getlost($r,'Invalid call of handler');
    return OK;
 }
 
