#!/usr/bin/perl -w

use strict;
use File::Find;
use Cwd;

my ( $s1 , $s2 , $name ) ;
my ( %checksum ) ;
my $num_diff = 0 ;

my $cwd = cwd() ;

# What kinda name is bm build?
sub _bm_build {
    my $condition = shift;
    my @regexp = @_;  # this MUST not be local(); need my()
    my $expr = join $condition => map { "m/\$regexp[$_]/o" } (0..$#regexp);
    my $match_func = eval "sub { $expr }";
    die if $@;  # propagate $@; this shouldn't happen!
    return $match_func;
}

# BM or else what???
sub bm_or  { _bm_build('||', @_) }

my $ignore_file = bm_or qw{ checksums io_src swig \.svn docs xml(/|$) \.\.\. object compout
                  lib_[DRIS] \.[oa]$ \.clex$ _lex\.c \.y.[ch] \.l.c Master.cpp 
                  bin_  mini_catalog catalog/  dr_name_parser.[ch] 
                  input_parser.[ch]  ref_parser.[ch] monte_parser.[ch] 
                  \.orig } ;

my $trick_checksums = "$ENV{TRICK_HOME}/bin/checksums" ;
chdir "$ENV{TRICK_HOME}" ;
open CHECK, "$trick_checksums" or die "could not open $trick_checksums" ;
while (<CHECK>) {
        ( $s1 , $s2 , $name ) = split ;
        $checksum{$name} = { s1 => $s1 , s2 => $s2 } ;
}
close CHECK ;

find(\&verify_checksum, '.');

exit($num_diff) ;

sub verify_checksum {
    my $curr_name = $_ ;
    my $name = $File::Find::name ;
    my $sum ;
    my ($s1 , $s2) ;
    my $full_name ;
    $_ = $name ;
    return if ( &$ignore_file ) ;
    ($full_name = $name) =~ s!^\./!$ENV{TRICK_HOME}/! ;
    if ( $full_name ne "" and ! -d $full_name ) {
        if ( $^O eq "linux" ) {
            $sum = `/usr/bin/sum -s $full_name` ;
        }
        elsif ( $^O eq "darwin" ) {
            $sum = `/usr/bin/cksum -o 2 $full_name`
        }
        else {
            $sum = `/usr/bin/sum $full_name`
        }
  
        ($s1 , $s2) =  $sum =~ /(\d+)\s+(\d+)/ ;
        #printf "%5d %10d %s\n" , $s1 , $s2 , $name ;
        if ( ! exists $checksum{$name} ) {
            print "New file $name\n" ;
            $num_diff++ ;
        }
        elsif ( $s1 != $checksum{$name}{s1} or 
                $s2 != $checksum{$name}{s2} ) {
            print "Checksum difference for $name\n" ;
            $num_diff++ ;
        }
 
    }
}