use strict;
use File::Copy;
use File::Find;
use File::Compare;
use Time::HiRes qw(time);

my $source   = "G:\\contingency\\";
my $maindest = "D:\\";

( -r $source ) || die "Error:  $source not readable\n";
( -e $maindest )
  || die
"Error:  $maindest (memory stick) does not exist--is your memory stick attached?\n";

print "Beginning scan of source directory for updated files...\n\n";

# for the convenience of &wanted calls, including -eval statements:
use vars qw/*name *dir *prune/;
*name  = *File::Find::name;
*dir   = *File::Find::dir;
*prune = *File::Find::prune;

my $newdirs        = 0;
my $newfiles       = 0;
my $changedfiles   = 0;
my $unchangedfiles = 0;
my $orphans        = 0;
my $startcompcopy  = time;
my $status1        = find( \&wantedtime, $source );
my $endcompcopy    = time;
printf "Synchronization took %f seconds.\n\n", $endcompcopy - $startcompcopy;

my $totalfiles = $newdirs + $newfiles + $changedfiles + $unchangedfiles;
print "Summary report:  \n";
print "$totalfiles entries scanned.\n";
print "$newdirs new directories found and created.\n";
print "$newfiles new files found and copied.\n";
print "$changedfiles updated files copied.\n";
print "$unchangedfiles unchanged files ignored.\n\n";

#..and then take care of orphans
print "searching for orphans:\n";
my $dest1 = $source;
$dest1 =~ s/G:/D:/;
my @filesizes;

#use finddepth here cos we're deleting
my $status1 = finddepth( \&wantedorphans, $dest1 );

print "$orphans orphans deleted from memory stick.\n\n";

print "This program will now pause for 10 seconds, then exit.\n";

sleep 10;

sub wantedtime {
    my $dest = $name;
    $dest =~ s/G:/D:/;
    if ( not -e $dest ) {
        if ( -d $name ) {
            print "Making new directory $dest\n";
            mkdir $dest;
            ++$newdirs;
        }
        else {
            print "Copying previously nonexistent file $dest\n";
            my $cstatus = copy( $name, $dest );

            #copy returns 1 on success
            ++$newfiles;
            ($cstatus)
              || warn
              "WARNING:  Copy of $name failed with status $cstatus: $!\n";
        }
    }
    else {

        #Not doing this for directories as empty dirs are taken care of above
        #and copying an entire directory won't work with copy()
        if ( -d $name ) {
            print "scanning $name...\n";
        }
        else {
            my $smtime = ( stat($name) )[9];
            my $dmtime = ( stat($dest) )[9];
            if ( ( $smtime > $dmtime ) ) {
                print
                  "Updated file found!\n Copying $name\n to memory stick \n";
                my $cstatus = copy( $name, $dest );

                #copy returns 1 on success
                ($cstatus)
                  || warn
                  "WARNING:  Copy of $name failed with status $cstatus: $!\n";
                ++$changedfiles;
            }
            else {
                ++$unchangedfiles;
            }
        }
    }
}

sub wantedorphans {
    my $status = 1;
    $source = $name;
    $source =~ s/D:/G:/;
    if ( not -e $source ) {
        ++$orphans;
        print "$name is an orphan; deleting...\n";
        if ( -d $name ) {
            $status = rmdir $name;
        }
        else {
            $status = unlink $name;
        }

#rmidr returns true on success; unlink returns number of files deleted (should be 1)
        ($status)
          || warn "WARNING:  Status of removal of $name is $status : $!\n";
    }
}