#!/usr/bin/perl -w

require 5.006; # i'm using "open my $fh ..." construct

use strict;

# =================================================
# constants

# put magic constants at top, so people can easily change them

my $CHARGE_CODES_FILE = "mnta2/bmp/table/smsc/chg_indicator.hdb";

my $INPUT_TEMPLATE = "A12 A4 A20 A20
                      A2  A2 A2  A2
                      A12 A4 A24 A24";

my $SOURCE_IX = 2;
my $DEST_IX   = 3;

# =================================================

# first, load up the charge database.
my %charge_codes;
{
    open my $fh, $CHARGE_CODE_FILE
      or die "$0: opening '$CHARGE_CODE_FILE': $!";
    while ( <$fh> )
    {
        next if /^#/;      # skip comments
        s/\s+$/;           # remove end of line chars

        # get fields from line, clean them up.
        my ( $src, $dest, $code ) = split /,/;
        $src  =~ s/^0+//;
        $dest =~ s/^0+//;

        $charge_codes{$src}{$dest} = $code;
    }
}

# -------------------------------------------------
# process standard input, accumulate charges.

my %charges_against;

while ( my $input = <> )
{
    # extract source and destination values
    my @fields = unpack $INPUT_TEMPLATE, $input;
    my $src  = $fields[ $SOURCE_IX ];
    my $dest = $fields[ $DEST_IX ];

    # remove leading zeros
    $src  =~ s/^0+//;
    $dest =~ s/^0+//;

    # see if there are any charge codes associated with this pair.
    my $code = $charge_codes{$src}{$dest};
    if ( defined $code )
    {
        ++$charges_against{$code};
    }
}

# -------------------------------------------------
# output the results

foreach my $code ( sort keys %charges_against )
{
    my $count = $charges_against{$code};
    print "Total calls for Billing Code [$code] : $count \n";
}

# note that skip_zero is no longer necessary.