1 files changed, 124 insertions, 0 deletions
diff --git a/bin/extract-zugbildung-for-today b/bin/extract-zugbildung-for-today
new file mode 100755
index 0000000..43922e4
--- /dev/null
+++ b/bin/extract-zugbildung-for-today
@@ -0,0 +1,124 @@
+#!/usr/bin/env perl
+# Copyright (C) 2020 Daniel Friesel
+#
+# SPDX-License-Identifier: BSD-2-Clause
+
+use strict;
+use warnings;
+use 5.020;
+use utf8;
+
+use DateTime;
+use DateTime::Format::Strptime;
+use File::Slurp qw(read_file);
+use JSON;
+
+my $strp = DateTime::Format::Strptime->new(
+	pattern   => '%F',
+	time_zone => 'Europe/Berlin'
+);
+my $now = DateTime->now( time_zone => 'Europe/Berlin' );
+
+sub range_is_today {
+	my ($range) = @_;
+
+	if ( $range =~ m{^(.*)/(.*)$} ) {
+		my $dt1 = $strp->parse_datetime($1);
+		my $dt2 = $strp->parse_datetime($2);
+		if ( $dt1 and $dt2 and $dt1->epoch < $now->epoch < $dt2->epoch ) {
+			return 1;
+		}
+	}
+	else {
+		if ( my $dt = $strp->parse_datetime($range) ) {
+			if ( $dt->ymd eq $now->ymd ) {
+				return 1;
+			}
+		}
+	}
+	return;
+}
+
+sub weekday_is_today {
+	my ($weekdys) = @_;
+
+	return ( ${ $weekdys->[ $now->day_of_week - 1 ] } == 1 );
+}
+
+if ( @ARGV == 0 ) {
+	exit 1;
+}
+
+my $data = JSON->new->utf8->decode( read_file( $ARGV[0] ) );
+
+my %map = %{ $data->{train_variants} };
+my %smap;
+
+for my $train_no ( keys %map ) {
+	if ( @{ $map{$train_no} } == 1 ) {
+		$smap{$train_no} = $map{$train_no}[0];
+	}
+	else {
+		my $latest_valid;
+		my $valid_count = 0;
+		for my $train ( @{ $map{$train_no} } ) {
+			my $is_valid = 0;
+			for my $schedule ( @{ $train->{schedules} // [] } ) {
+				for my $valid ( @{ $schedule->{valid} // [] } ) {
+					if ( range_is_today($valid) ) {
+						$is_valid = 1;
+					}
+				}
+
+				# invalid may override valid for certain days
+				for my $invalid ( @{ $schedule->{invalid} // [] } ) {
+					if ( range_is_today($invalid) ) {
+						$is_valid = 0;
+					}
+				}
+			}
+			if ($is_valid) {
+				$latest_valid = $train;
+				$valid_count++;
+			}
+		}
+		if ( $valid_count == 1 ) {
+			$smap{$train_no} = $latest_valid;
+		}
+		else {
+			$valid_count  = 0;
+			$latest_valid = undef;
+			for my $train ( @{ $map{$train_no} } ) {
+				my $is_valid = 0;
+				for my $schedule ( @{ $train->{schedules} // [] } ) {
+					for my $valid ( @{ $schedule->{valid} // [] } ) {
+						if (    range_is_today($valid)
+							and weekday_is_today( $schedule->{weekdays} ) )
+						{
+							$is_valid = 1;
+						}
+					}
+
+					# invalid may override valid for certain days
+					for my $invalid ( @{ $schedule->{invalid} // [] } ) {
+						if ( range_is_today($invalid) ) {
+							$is_valid = 0;
+						}
+					}
+				}
+				if ($is_valid) {
+					$latest_valid = $train;
+					$valid_count++;
+				}
+			}
+			if ( $valid_count == 1 ) {
+				$smap{$train_no} = $latest_valid;
+			}
+		}
+	}
+}
+
+delete $data->{train_variants};
+$data->{train} = {%smap};
+
+say JSON->new->utf8->canonical->encode($data);