#!/usr/local/bin/perl -w
use 5.01;
use strict;
use utf8;
use warnings;
use Device::Inverter::KOSTAL::PIKO;
die "USAGE: $0 <file>+\n" unless @ARGV;
my $tty;
if   ( open $tty, '>', '/dev/tty' ) { $tty->autoflush }
else                                { undef $tty }
sub progress($) { print $tty shift if defined $tty }
sub records($;$) {
    my ( $records, $prefix ) = @_;
    $prefix //= '';
    "$records ${prefix}record" . ( $records != 1 && 's' );
}
my $piko = Device::Inverter::KOSTAL::PIKO->new;
my $data;
for (@ARGV) {
    ( my $file = $piko->load( $_ eq '-' ? \*STDIN : $_ ) )->close;
    progress( 'Read '
          . records( $file->logdata_records )
          . ' from '
          . ( $_ eq '-' ? 'standard input' : qq(file "$_") ) );
    if ($data) {
        my $new_records = $data->merge($file);
        progress( ' => ' . records( $new_records, 'new ' ) );
    }
    else {    # first file
        $data = $file;
    }
    progress("\n");
}
binmode STDOUT, ':crlf';
$data->print;