#!/usr/bin/env perl

use strict;
use warnings;
use 5.020;
use utf8;

use File::Slurp qw(read_file);
use JSON;

sub show_usage {
	my ($exit_code) = @_;

	say STDERR "Usage: sanity-check <zugbildung.json>";

	exit $exit_code;
}

binmode( STDOUT, ':encoding(utf-8)' );

if ( @ARGV < 1 ) {
	show_usage(1);
}

my ($file) = @ARGV;

my $file_content = read_file($file);
my $json         = JSON->new->utf8->decode($file_content);

my $map = $json->{train};

for my $train_number ( sort { $a <=> $b } keys %{$map} ) {
	for my $cycle_from ( @{ $map->{$train_number}{cycle}{from} // [] } ) {
		if ( not exists $map->{$cycle_from} ) {
			printf(
				"%s %d references unknown train %d\n",
				$map->{$train_number}{raw},
				$train_number, $cycle_from
			);
		}
	}
	for my $cycle_to ( @{ $map->{$train_number}{cycle}{to} // [] } ) {
		if ( not exists $map->{$cycle_to} ) {
			printf(
				"%s %d references unknown train %d\n",
				$map->{$train_number}{raw},
				$train_number, $cycle_to
			);
		}
	}
}