--- nfo/perl/libs/DesignPattern/Bridge.pm	2003/01/31 01:19:50	1.5
+++ nfo/perl/libs/DesignPattern/Bridge.pm	2003/02/21 08:38:21	1.11
@@ -1,7 +1,28 @@
 ## --------------------------------------------------------------------------------
-##  $Id: Bridge.pm,v 1.5 2003/01/31 01:19:50 root Exp $
+##  $Id: Bridge.pm,v 1.11 2003/02/21 08:38:21 joko Exp $
 ## --------------------------------------------------------------------------------
 ##  $Log: Bridge.pm,v $
+##  Revision 1.11  2003/02/21 08:38:21  joko
+##  + additional checks
+##  + raising exceptions
+##
+##  Revision 1.10  2003/02/20 20:50:32  joko
+##  + small exception handling: now inheriting from little Exception object
+##
+##  Revision 1.9  2003/02/18 18:35:30  joko
+##  + encapsulated/abstracted some more functionality: sub load_single
+##
+##  Revision 1.8  2003/02/14 14:20:05  joko
+##  + modified mixin behaviour
+##
+##  Revision 1.7  2003/02/11 10:34:19  joko
+##  + loaded module may now lack 'mixin::with' declaration
+##  + this gets us the possibility to load modules from any perl namespace
+##     + enabled this mechanism
+##
+##  Revision 1.6  2003/02/09 16:22:51  joko
+##  + pseudo constructor mechanism via options
+##
 ##  Revision 1.5  2003/01/31 01:19:50  root
 ##  + fixed: doesn't need Log::Dispatch any more, but uses it if available
 ##
@@ -26,13 +47,18 @@
 use strict;
 use warnings;
 
-use base qw( DesignPattern::Object );
+use base qw( 
+  DesignPattern::Object
+  DesignPattern::Exception
+);
+
 
 use Data::Dumper;
 
 ## ========   object inheritance   ========
 
-# TODO:
+# TODO / REFACTORING PROPOSAL
+# leading from Data::Storage to code abstracted out into this module - DesignPattern::Bridge
 #   - this is no inheritance and it doesn't have to be
 #   - implement this module as a bridge to its sub-modules
 #   - use the BridgePattern (http://c2.com/cgi/wiki?BridgePattern) 
@@ -43,27 +69,31 @@
 #   - sub getChildNodes
 #   - sub run
 
+# 2003-02-11, joko: does this have anything in parallel with CPAN's Class::Inner?
+
+
 # get logger instance
 my $logger = eval { Log::Dispatch::Config->instance; };
   
 my $meta;
 
 ## ========   object constructor   ========
-  sub new {
-    my $invocant = shift;
-    my $class = ref($invocant) || $invocant;
-    my @args = ();
-    @_ && (@args = @_);
-    $logger->debug( __PACKAGE__ . "->new(@args)" ) if $logger;
-    my $self = { @_ };
+sub new {
+  my $invocant = shift;
+  my $class = ref($invocant) || $invocant;
+  my @args = ();
+  @_ && (@args = @_);
+  $logger->debug( __PACKAGE__ . "->new(@args)" ) if $logger;
+  my $self = { @_ };
+
+  # trace
     #print "class: $class", "\n";
-    bless $self, $class;
-    ##if (my $bizWorks = shift) {
-      ##$self->boot($bizWorks);
-    ##}
-    
-    return $self;
-  }
+
+  # create instance
+  bless $self, $class;
+  
+  return $self;
+}
 
 
 ## ========   method overrider   ========
@@ -98,15 +128,41 @@
     
     # build full package name
     my $self_classname = ref $self;
-    my $package = $self_classname . '::' . $modulename_load;
+      # name
+      my $package = $modulename_load;
+      
+      # if package is absolute, cut away prefix ('/' or '::')
+      if ($package !~ s/^:://) {
+        # else: prefix with base classname if above name is relative (lacks of '/' or '::')
+        $package = $self_classname . '::' . $package 
+      }
+    
     return $package;
   }
   
   sub load {
 
     my $self = shift;
+    my $modulename = shift;
+    my $options = shift;
+
+    if (ref $modulename eq 'ARRAY') {
+      foreach (@$modulename) {
+        $self->load_single($_, $options);
+      }
+    } else {
+      $self->load_single($modulename, $options);
+    }
+
+  }
+
+  sub load_single {
+
+    my $self = shift;
     my $modulename_load = shift;
 
+    my $options = shift;
+
     my $self_modulename = ref $self;
     my $package = $self->_getPluginPackage($modulename_load);
     
@@ -120,6 +176,9 @@
 
     # this is the module testing phase - use mixin doesn't seem to propagate errors by default
     eval("use $package;");
+    $self->checkExceptions();
+    
+=pod    
     if ($@) {
       $meta->{loaded}->{$package} = 0;
       # include caller information
@@ -132,6 +191,7 @@
         print $msg, "\n";
       }
     }
+=cut
 
 #print "ref-1: ", ref $self, "\n";
 #print "ref-2: ", ref $self::SUPER, "\n";
@@ -140,27 +200,63 @@
     #bless $self, $package;
 
     # V2:
-    # switch into foreign package and mixin plugin-module
     $self->mixinPackage($package);
+    
+    if (my $method = $options->{method}) {
+      $self->$method();
+    }
 
     return 1;
     
   }
+  
+  sub mixinPackage {
+    my $self = shift;
+    my $package = shift;
+    
+    # switch into foreign package and prepare for mixin
+    $self->mixin_prepare($package);
+
+    # switch into local package (scope which uses DesignPattern::Bridge) and mixin plugin-module
+    $self->mixin_do($package);
+
+  }
 
   # TODO: maybe refactor to DesignPattern::Object? what about the '$logger'?
-  sub mixinPackage {
+  sub mixin_prepare {
+    my $self = shift;
+    my $package = shift;
+    my $self_classname = ref $self;
+    eval("package $package; use mixin::with '$self_classname';");
+
+    # FIXME: --- this is redundant ---
+    if ($@) {
+      $meta->{loaded}->{$package} = 0;
+      $logger->error( __PACKAGE__ . "->load: $@" ) if $logger;
+    } else {
+      $meta->{loaded}->{$package} = 1;
+    }
+    # FIXME: --- this is redundant ---
+
+  }
+
+  sub mixin_do {
     my $self = shift;
     my $package = shift;
     # switch into foreign package and mixin plugin-module
     my $self_classname = ref $self;
     eval("package $self_classname; use mixin '$package';");
     #eval("use mixin_all '$package';");
+
+    # FIXME: --- this is redundant ---
     if ($@) {
       $meta->{loaded}->{$package} = 0;
       $logger->error( __PACKAGE__ . "->load: $@" ) if $logger;
     } else {
       $meta->{loaded}->{$package} = 1;
     }
+    # FIXME: --- this is redundant ---
+
   }
 
   sub unload {
@@ -188,9 +284,22 @@
     my $self = shift;
     my $includefile = shift;
     my $package = shift;
-    # TODO: do better error-detection here / prevent dies under all circumstances!
-    require $includefile;
+    
+    # pre-flight checks
+    if (!$includefile) {
+      $self->raiseException('Filename for inclusion was empty.');
+      return;
+    }
+    
+    # go for it ...
+    eval("require '$includefile';");
+    # ... and handle errors afterwards catching every message from perl itself ...
+    return if $self->checkExceptions();
+    
+    # ... otherwise continue assuming everything is fine
     $self->mixinPackage($package) if $package;
+    
   }
 
 1;
+__END__