--- rat/lonuserstate.pm	2000/08/02 15:27:10	1.2
+++ rat/lonuserstate.pm	2000/08/06 03:25:24	1.3
@@ -10,7 +10,7 @@
 # 7/1 Gerd Kortemeyer)
 # 7/1,7/3,7/4,7/7,7/8,7/10 Gerd Kortemeyer)
 #
-# 7/15,7/17,7/18,8/1,8/2 Gerd Kortemeyer
+# 7/15,7/17,7/18,8/1,8/2,8/4,8/5 Gerd Kortemeyer
 
 package Apache::lonuserstate;
 
@@ -175,21 +175,49 @@ sub loadmap {
     }
 }
 
+# --------------------------------------------------------- Simplify expression
+
+sub simplify {
+   my $expression=shift;
+# "True and" is nothing 
+   $expression=~s/0\&//g;
+# (8)=8
+   $expression=~s/\((\d+)\)/$1/g;
+# 8&8=8
+   $expression=~s/(\d+)\&\1/$1/g;
+# 8|8=8
+   $expression=~s/(\d+)\|\1/$1/g;
+# (5&3)&4=5&3&4
+   $expression=~s/\((\d+)\&(\d+)\)\&(\d+)/$1\&$2\&$3/g;
+# (((5&3)|(4&6)))=((5&3)|(4&6))
+   $expression=~
+       s/\((\(\(\d+(?:\&\d+)*\)(?:\|\(\d+(?:\&\d+)*\))+\))\)/$1/g;
+# ((5&3)|(4&6))|(1&2)=(5&3)|(4&6)|(1&2)
+   $expression=~
+       s/\((\(\d+(?:\&\d+)*\))((?:\|\(\d+(?:\&\d+)*\))+)\)\|(\(\d+(?:\&\d+)*\))/\($1$2\|$3\)/g;
+   return $expression;
+}
+
 # -------------------------------------------------------- Build condition hash
 
 sub traceroute {
-    my ($sofar,$rid,$beenhere)=shift;
+    my ($sofar,$rid,$beenhere)=@_;
+    $sofar=simplify($sofar);
     unless ($beenhere=~/\&$rid\&/) {
        $beenhere.=$rid.'&';  
        if (defined($hash{'conditions_'.$rid})) {
-	   $hash{'conditions_'.$rid}=
-       '('.$hash{'conditions_'.$rid}.')|('.$sofar.')';
+	   $hash{'conditions_'.$rid}=simplify(
+           '('.$hash{'conditions_'.$rid}.')|('.$sofar.')');
        } else {
            $hash{'conditions_'.$rid}=$sofar;
        }
        if (defined($hash{'is_map_'.$rid})) {
-           if () {
-	       &traceroute($sofar,$startrid,'&');
+           if (defined($hash{'map_start_'.$hash{'src_'.$rid}})) {
+	       &traceroute($sofar,$hash{'map_start_'.$hash{'src_'.$rid}},'&');
+               if (defined($hash{'map_finish_'.$hash{'src_'.$rid}})) {
+		   $sofar=
+                  $hash{'conditions_'.$hash{'map_finish_'.$hash{'src_'.$rid}}};
+               }
            }
        }
        if (defined($hash{'to_'.$rid})) {
@@ -197,7 +225,8 @@ sub traceroute {
 		my $further=$sofar;
                 if ($hash{'undercond_'.$_}) {
 		   if (defined($hash{'condid_'.$hash{'undercond_'.$_}})) {
-  		       $further.='&'.$hash{'condid_'.$hash{'undercond_'.$_}};
+  		       $further=simplify('('.$further.')&('.
+                              $hash{'condid_'.$hash{'undercond_'.$_}}.')');
 		   } else {
                        $errtext.='Undefined condition ID: '
                                  .$hash{'undercond_'.$_}.'. ';
@@ -213,11 +242,14 @@ sub traceroute {
 
 sub readmap {
    my $uri=shift;
-   @cond=();
+   @cond=('true:normal');
    %hash=();
    $errtext='';
    $pc=0;
    loadmap($uri);
+   if (defined($hash{'map_start_'.$uri})) {
+       &traceroute('0',$hash{'map_start_'.$uri},'&');
+   }
 }
 
 # ---------------------------------------------------------------- Testing only