use strict;
use sigtrap qw(die INT);
use Win32::OLE qw(in EVENTS);
use Win32::OLE::Variant;
$| = 1;
# Without this, you end up registering the same event multiple times...
# However, check the docs, as there is a performance penalty...
Win32::OLE->Option(_Unique => 1);

# Excel 10 "Dispatch" interfaces for Win32::OLE->WithEvents
# Application: AppEvents
# Sheets:      DocEvents
# Charts:      ChartEvents
# Workbooks:   WorkbookEvents
# OLE:         OLEObjectEvents

sub kill_excel {
    my $self = shift;
    $self->Quit;
}

END {
my $Count = Win32::OLE->EnumAllObjects(sub {
            my $Object = shift;
            my $Class = Win32::OLE->QueryObjectType($Object);
            printf "# Object=%s Class=%s\n", $Object, $Class;
        });
print $Count,$/;
}

my $xl_app = Win32::OLE->new('Excel.Application', \&kill_excel);
$xl_app->{Visible} = 1;

my %wkb;
my %sheets;

sub get_ole_type {
  return Win32::OLE->QueryObjectType(shift);
}

sub app_event_handler {
  my ($obj, $event, @args) = @_;
  #print "app_event_handler: ", get_ole_type($obj), " ($obj->{Name}) : Event: $event",$/;
  my $new_item = $args[0];
  if ($event eq'NewWorkbook'||
      $event eq 'WorkbookActivate'
     ){
    print "app_event_handler: ", get_ole_type($obj), " ($obj->{Name}) : Event: <$event>",$/;
    print $new_item->{BuiltinDocumentProperties}->{"Creation Date"};
    print $new_item, ":",join("<->", keys %wkb), $/;
    unless ($wkb{$new_item}){
      my $w = $new_item;
      print "Registering event handler for Workbook: $w->{Name}",$/;
      Win32::OLE->WithEvents($w, \&wb_event_handler, 'WorkbookEvents');
	  $wkb{$w} = $new_item;
      for my $s (in $w->Worksheets()) {
	$sheets{$s} = $s unless $sheets{$s};
	print "Registering event handler for sheet $s->{Name} in book $s->{Parent}->{Name}",$/;
	Win32::OLE->WithEvents($s, \&sheet_event_handler, 'DocEvents');
      }
    }
  }
}

Win32::OLE->WithEvents($xl_app, \&app_event_handler, 'AppEvents');


sub sheet_event_handler {
  my ($obj, $event, @args) = @_;
  print "sheet_event_handler: ",get_ole_type($obj), " ($obj->{Name}) : Event: <$event>",$/;
  if ($event eq 'SelectionChange' || 
      $event eq 'Change') {
    my $range = $args[0];
    print "$event received with " . get_ole_type($range) . " as argument",$/;
    print <<EOF;
The target range has: $range->{Columns}->{Count} column(s) and $range->{Rows}->{Count} row(s)
It spans cell(s) $range->{Address}
EOF
  }
  if ($event eq 'Change') {
    for my $cell ( in $args[0]->{Cells}) {
      print "Cell $cell->{Address} contains: $cell->{Value}",$/;
    }
  }
}

sub wb_event_handler {
  my ($obj, $event, @args) = @_;
  print "wb_event_handler: ",get_ole_type($obj), " ($obj->{Name}) : Event: <$event>",$/;
}


while (1) {
    $xl_app->SpinMessageLoop();
}