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#!/usr/bin/env perl
## Copyright © 2009-2015 by Daniel Friesel <derf@finalrewind.org>
## License: WTFPL <http://sam.zoy.org/wtfpl>
##   0. You just DO WHAT THE FUCK YOU WANT TO.
use strict;
use warnings;
use 5.010;

no if $] >= 5.018, warnings => 'experimental::smartmatch';

use utf8;

use Encode qw(decode);
use Travel::Routing::DE::EFA;
use Exception::Class;
use Getopt::Long qw/:config no_ignore_case/;
use List::Util qw(first);

our $VERSION = '2.18';
my $ignore_info;
my $efa;
my $efa_url = 'http://efa.vrr.de/vrr/XSLT_TRIP_REQUEST2';
my ( @from, @to, @via, $from_type, $to_type, $via_type );
my $opt = {
	'efa-url'     => \$efa_url,
	'help'        => sub { show_help(0) },
	'ignore-info' => \$ignore_info,
	'from'        => \@from,
	'to'          => \@to,
	'version'     => sub { say "efa version $VERSION"; exit 0 },
	'via'         => \@via,
};

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

sub show_help {
	my ($exit_status) = @_;

	say 'Usage: efa [options] <from-city> <from-stop> <to-city> <to-stop>';
	say 'See also: man efa';

	exit $exit_status;
}

sub new_efa_by_url {
	my ($url) = @_;
	my $res = eval {
		Travel::Routing::DE::EFA->new(
			efa_url => $url,

			origin      => [ @from, $from_type ],
			destination => [ @to,   $to_type ],
			via => ( @via ? [ @via, $via_type ] : undef ),

			arrival_time   => $opt->{arrive},
			departure_time => $opt->{depart},
			date           => $opt->{date},
			exclude        => $opt->{exclude},
			train_type     => $opt->{include},
			with_bike      => $opt->{bike},

			select_interchange_by => $opt->{prefer},
			use_near_stops        => $opt->{proximity},
			walk_speed            => $opt->{'walk-speed'},
			max_interchanges      => $opt->{'max-change'},
			num_results           => $opt->{'num-connections'},

			without_solid_stairs => $opt->{without_solid_stairs},
			without_escalators   => $opt->{without_escalators},
			without_elevators    => $opt->{without_elevators},
			with_low_platform    => $opt->{with_low_platform},
			with_wheelchair      => $opt->{with_wheelchair},

			developer_mode => $opt->{devmode},
			lwp_options    => { timeout => $opt->{timeout} },
		);
	};
	return $res;
}

sub handle_efa_exception {
	my ($e) = @_;

	if ( $e->isa('Travel::Routing::DE::EFA::Exception::Setup') ) {
		if ( $e->message ) {
			printf STDERR (
				"User error: %s (option '%s'): %s%s\n",
				$e->description, $e->option, $e->message,
				$e->have ? q{ "} . $e->have . q{"} : q{},
			);
		}
		else {
			printf STDERR (
				"User error: %s (option '%s', got '%s', want '%s')\n",
				$e->description, $e->option, $e->have, $e->want
			);
		}

		exit 1;
	}
	if ( $e->isa('Travel::Routing::DE::EFA::Exception::Net') ) {
		printf STDERR (
			"Network error: %s: %s\n",
			$e->description, $e->http_response->as_string
		);
		exit 2;
	}
	if ( $e->isa('Travel::Routing::DE::EFA::Exception::NoData') ) {
		printf STDERR ( "Backend error: %s\n", $e->description );
		exit 3;
	}
	if ( $e->isa('Travel::Routing::DE::EFA::Exception::Ambiguous') ) {
		printf STDERR (
			"Backend error: The %s '%s' is ambiguous. Try one of %s\n",
			$e->post_key, $e->post_value,, $e->possibilities
		);
		exit 4;
	}
	if ( $e->isa('Travel::Routing::DE::EFA::Exception::Other') ) {
		printf STDERR ( "Backend error: %s: %s\n", $e->description,
			$e->message );
		exit 5;
	}

	printf STDERR ( "Unknown error: %s\n%s", ref($e), $e->trace );
	exit 10;
}

sub check_for_error {
	my ($eval_error) = @_;

	if ( not defined $efa ) {
		if (    $eval_error
			and ref($eval_error)
			and $eval_error->isa('Travel::Routing::DE::EFA::Exception') )
		{
			handle_efa_exception($eval_error);
		}
		elsif ($eval_error) {
			printf STDERR
			  "Unknown Travel::Routing::DE::EFA error:\n${eval_error}";
			exit 10;
		}
		else {
			say STDERR 'Travel::Routing::DE::EFA failed to return an object';
			exit 10;
		}
	}

	return;
}

sub format_footpath {
	my @parts = @_;
	my $str   = q{};

	for my $path_elem (@parts) {
		my ( $type, $level ) = @{$path_elem};
		if ( $level eq 'UP' ) {
			$str .= ' ↗';
		}
		elsif ( $level eq 'DOWN' ) {
			$str .= ' ↘';
		}
		elsif ( $level eq 'LEVEL' ) {
			$str .= ' →';
		}
		else {
			$str .= " [unhandled level, please report a bug : $level]";
		}
	}

	return $str;
}

sub display_routes {
	my (@routes) = @_;

	for my $i ( 0 .. $#routes ) {

		my $route = $routes[$i];

		if ( $opt->{'extended-info'} ) {
			print '# ' . $route->duration;
			if ( $route->ticket_type ) {
				printf( ", Preisstufe %s (%s€ / %s€)\n\n",
					$route->ticket_type, $route->fare_adult,
					$route->fare_child, );
			}
			else {
				print "\n\n";
			}
		}

		for my $c ( $route->parts ) {
			display_connection($c);
		}

		# last one needs to be shown separately
		if ( $opt->{maps} ) {
			my $c = ( $route->parts )[-1];
			for my $m ( $c->arrival_routemaps, $c->arrival_stationmaps ) {
				say "# $m";
			}
		}

		if ( $i != $#routes ) {
			print "---------\n\n";
		}
	}
	return;
}

sub display_connection {
	my ($c) = @_;

	if ( $c->is_cancelled ) {
		say '# FAHRT FÄLLT AUS';
	}
	elsif ( $c->delay ) {
		printf( "# +%d,  Plan: %s -> %s\n",
			$c->delay, $c->departure_stime, $c->arrival_stime );
	}

	for my $note ( $c->regular_notes ) {
		my $text = $note->summary;
		if ( not( length $ignore_info and $text =~ /$ignore_info/i ) ) {
			say "# $text";
		}
	}

	for my $notice ( $c->current_notes ) {
		if ( $notice->subtitle ne $notice->subject ) {
			printf( "# %s - %s\n", $notice->subtitle, $notice->subject );
		}
		else {
			printf( "# %s\n", $notice->subtitle );
		}
	}

	if ( $opt->{maps} ) {
		for my $m ( $c->departure_routemaps, $c->departure_stationmaps ) {
			say "# $m";
		}
	}

	printf(
		"%-5s ab  %-30s %-20s %s\n",
		$c->departure_time,
		$c->departure_stop_and_platform,
		$c->train_line || $c->train_product,
		$c->train_destination,
	);

	if ( $opt->{'full-route'} ) {
		for my $via_stop ( $c->via ) {
			printf( "%-5s     %-30s %s\n",
				$via_stop->[1], $via_stop->[2], $via_stop->[3] );
		}
	}

	printf( "%-5s an  %s\n", $c->arrival_time, $c->arrival_stop_and_platform, );
	print "\n";

	if (    $opt->{'extended-info'}
		and $c->footpath_duration
		and $c->footpath_type ne 'IDEST' )
	{
		printf( "%5d min umsteigen: %s\n\n",
			$c->footpath_duration, format_footpath( $c->footpath_parts ) );
	}

	return;
}

@ARGV = map { decode( 'UTF-8', $_ ) } @ARGV;

#<<<
GetOptions(
	$opt,
	qw{
		accessibility|x=s@
		arrive|a=s
		auto-url|discover-and-print|A
		bike|b
		bike-info|B
		date|d=s
		depart|time|t=s
		devmode
		discover|D
		efa-url|u=s
		exclude|e=s@
		extended-info|E
		from=s@{2}
		full-route|f
		help|h
		ignore-info|I:s
		include|i=s
		list|l
		maps|M
		max-change|m=i
		num-connections|n=i
		prefer|P=s
		proximity|p:10
		service|s=s
		timeout=i
		to=s@{2}
		version|v
		via=s@{2}
		walk-speed|w=s
	},
) or show_help(1);
#>>>

if ( $opt->{accessibility} ) {
	@{ $opt->{accessibility} }
	  = split( qr{,}, join( q{,}, @{ $opt->{accessibility} } ) );
}
else {
	# GetOptions seems to implicitly initialize $opt->{accessibility} to an
	# empty arrayref, but it's best not to rely on that.
	$opt->{accessibility} = [];
}

if ( $opt->{exclude} ) {
	@{ $opt->{exclude} } = split( qr{,}, join( q{,}, @{ $opt->{exclude} } ) );
}

for my $field ( @{ $opt->{accessibility} } ) {
	given ($field) {
		when ( [qw[s no-stairs]] )       { $opt->{without_solid_stairs} = 1 }
		when ( [qw[e no-escalators]] )   { $opt->{without_escalators}   = 1 }
		when ( [qw[E no-elevators]] )    { $opt->{without_elevators}    = 1 }
		when ( [qw[l nf low-platform]] ) { $opt->{with_low_platform}    = 1 }
		when ( [qw[w wheelchair]] )      { $opt->{with_wheelchair}      = 1 }
		when ( [qw[i info]] ) { }    # used for ignore_info default
	}
}

if ( $opt->{list} ) {
	printf( "%-40s %-14s %s\n\n", 'service', 'abbr. (-s)', 'url (-u)' );
	for my $service ( Travel::Routing::DE::EFA::get_efa_urls() ) {
		printf( "%-40s %-14s %s\n", @{$service}{qw(name shortname url)} );
	}
	exit 0;
}

if ( $opt->{arrive} and $opt->{depart} ) {
	print STDERR 'Note: The options -a/--arrive and -t/--time/--depart are'
	  . " mutually exclusive\n"
	  . "      Discarding the --arrive option\n\n";
	delete $opt->{arrive};
}

if ( not defined $ignore_info ) {
	$ignore_info = join(
		q{|},
		grep { defined } (
			@{ $opt->{accessibility} } ? undef : 'Einstiegshilfe',
			(
				     $opt->{bike}
				  or $opt->{'bike-info'}
			) ? undef : 'Fahrradmitnahme',
		)
	);
}
elsif ( defined $ignore_info and length($ignore_info) == 0 ) {
	$ignore_info = undef;
}

if ( not( @from and @to ) ) {
	if ( @ARGV == 4 ) {
		( @from[ 0, 1 ], @to[ 0, 1 ] ) = @ARGV;
	}
	elsif ( @ARGV == 6 ) {
		( @from[ 0, 1 ], @via[ 0, 1 ], @to[ 0, 1 ] ) = @ARGV;
	}
	else {
		show_help(1);
	}
}

for my $pair ( [ \@from, \$from_type ], [ \@via, \$via_type ],
	[ \@to, \$to_type ], )
{

	next if ( not defined $pair->[0]->[1] );

	if (
		$pair->[0]->[1] =~ s{ ^ (?<type> [^:]+ ) : \s* (?<target> .+ ) $ }
		{$+{target}}x
	  )
	{
		given ( $+{type} ) {
			when ('addr') { ${ $pair->[1] } = 'address' }
			default       { ${ $pair->[1] } = $+{type} }
		}
	}
}

if ( $opt->{service} ) {
	my $service = first { lc( $_->{shortname} ) eq lc( $opt->{service} ) }
	Travel::Routing::DE::EFA::get_efa_urls();
	if ( not $service ) {
		printf STDERR (
			"Error: Unknown service '%s'. See 'efa -l' for a "
			  . "list of supported service names\n",
			$opt->{service}
		);
		exit 1;
	}
	$efa_url = $service->{url};
}

if ( $opt->{discover} or $opt->{'auto-url'} ) {
	for my $service ( Travel::Routing::DE::EFA::get_efa_urls() ) {
		$efa = new_efa_by_url( $service->{url} );
		if ($efa) {
			if ( $opt->{'auto-url'} ) {
				last;
			}
			printf(
				"%s / %s (%s)\n   ->  efa -s %s %s\n\n",
				@{$service}{qw(name shortname url shortname)},
				join( q{ }, map { "'$_'" } @ARGV ),
			);
		}
	}
	if ( $opt->{'discover'} ) {
		exit 0;
	}
}
else {
	$efa = new_efa_by_url($efa_url);
}

check_for_error($@);

my @routes = $efa->routes;

display_routes( $efa->routes );

__END__

=head1 NAME

efa - Command line client for EFA-based public transit routing services

=head1 SYNOPSIS

=over

=item B<efa> B<--from> I<city> I<stop> B<--to> I<city> I<stop> [ I<additional options> ]

=item B<efa> [ I<options> ] I<from-city> I<from-stop> [ I<via-city> I<via-stop> ] I<to-city> I<to-stop>

=back

=head1 VERSION

version 2.18

=head1 DESCRIPTION

B<efa> is a command line client for EFA-based public transit routing
interfaces, e.g. L<http://efa.vrr.de>.  B<efa> requests connections between two
points and displays the results.

By default, the EFA service at L<http://efa.vrr.de> (operated by
Verkehrsverbund Rhein-Ruhr) is used, which supports most places in Germany.
A list of all supported EFA instances can be retrieved with B<-l> and a custom
instance can be selected using B<-s> I<service> or B<-u> I<url>. It is also
possible to probe all known EFA services for a specific connection using the
B<-A> and B<-D> options.

=head1 OPTIONS

=over

=item B<--from> I<city> I<stop>

Departure place

=item B<--to> I<city> I<stop>

Arrival place

=item B<--via> I<city> I<stop>

Travel via this place

In all cases, if you want I<stop> to be an address or "point of interest", you
can set it to 'addr:something' or 'poi:something'.

=item B<-a>|B<--arrive> I<hh>:I<mm>

Journey end time (overrides --time/--depart)

=item B<-A>|B<--auto-url>|B<--discover-and-print>

Probe all known EFA entry points for the specified connection. Print the first
result which was not an error.

Note that this may take a while and will not necessarily return the best
result.  Also, using this option by default is not recommended, as it puts
EFA services under considerable additional load.

=item B<-b>|B<--bike>

Request connections allowing the passenger to take a bike with them.
Note that this may cause B<efa> to display no routes at all -- In that case,
the backend was unable to find such connections or didn't know about
their bike-support.

=item B<-B>|B<--bike-info>

Show information about bike support, but do not select routes based on it.
In essence, this option simply changes the B<--ignore-info> default. It is
useful when B<--bike> did not return any routes even though most of the
route has bike support.

=item B<-d>|B<--date> I<dd>.I<mm>.[I<yyyy>]

Journey date. Also accepts the shortcut B<tomorrow>.

=item B<-D>|B<--discover>

Probe all known EFA entry points for the specified connection. No routes are
returned in this case. Instead, B<efa> will print the URLs and names of all
entry points which did not return an error.

=item B<-u>|B<--efa-url> I<url>

URL to the EFA entry point, defaults to
L<http://efa.vrr.de/vrr/XSLT_TRIP_REQUEST2>.  Depending on your location, some
I<url>s may contain more specific data than others. See
Travel::Routing::DE::EFA(3pm) and the B<-l> option for alternatives.

=item B<-e>|B<--exclude> I<transports>

Exclude I<transports> (comma separated list).

Possible transports: zug, s-bahn, u-bahn, stadtbahn, tram, stadtbus, regionalbus,
schnellbus, seilbahn, schiff, ast, sonstige

=item B<-E>|B<--extended-info>

Display more than just the basic route information. At the moment, the
following is displayed (if available):

=over

=item * Route duration

=item * Ticket fare

=item * transfer duration and elevation changes (via stairs / escalators)
at each stop

=back

=item B<-f>|B<--full-route>

Display intermediate stops (with time and platform) of each train.  Note that
these are not always available.

=item B<-I>|B<--ignore-info> [ I<regex> ]

Ignore additional information matching I<regex>
(default: /Fahrradmitnahme|Einstiegshilfe/)

If I<regex> is not supplied, removes the default regex (-E<gt> nothing will be ignored)

=item B<-i>|B<--include> I<type>

Include connections using trains of type I<type>, where I<type> may be:

=over

=item * local (default)

only take local trains ("Verbund-/Nahverkehrslinien"). Slow, but the cheapest
method if you're not traveling long distance

=item * ic

Local trains + IC

=item * ice

All trains (local + IC + ICE)

=back

=item B<-l>|B<--list>

List supported EFA services with their URLs (see B<-u>) and abbreviations
(see B<-s>).

=item B<-M>|B<--maps>

Output links to maps of transfer paths and transfer stations where
available.

=item B<-m>|B<--max-change> I<number>

Print connections with at most I<number> interchanges

=item B<-n>|B<--num-connections> I<number>

Return up to I<number> connections.  If unset, the default of the respective
EFA server is used (usually 4 or 5).

=item B<-P>|B<--prefer> I<type>

Prefer connections of I<type>:

=over

=item * speed (default)

The faster, the better

=item * nowait

Prefer connections with less interchanges

=item * nowalk

Prefer connections with less walking (at interchanges)

=back

=item B<-p>|B<--proximity> [I<minutes>]

Take stops close to the stop/start into account.  By default, up to 10 minutes
of walking to/from the route's first/last stop is considered acceptable. You
can specify I<minutes> to use a custom value.

=item B<-s>|B<--service> I<name>

Shortname of the EFA entry point. See Travel::Routing::DE::EFA(3pm) and
the B<-l> option for a list of services.

=item B<-t>|B<--time>|B<--depart> I<hh>:I<mm>

Journey start time

=item B<--timeout> I<seconds>

Set timeout for HTTP requests. Default: 60 seconds.

=item B<-v>|B<--version>

Print version information

=item B<-w>|B<--walk-speed> I<speed>

Set your walking speed to I<speed>.
Accepted values: normal (default), fast, slow

=item B<-x>|B<--accessibility> I<types>

Request connections satisfying all of the specified accessibility I<types>
(comma-separated list, option may be repeated). Please note that this may cause
the backend to return no results at all, either because no such connection
exists or because the required lines do not have the correct accessibility
attributes set.

The following I<types> are supported:

=over

=item e / no-escalators

Transfers must be possible without taking an escalator.

=item E / no-elevators

Transfers must be possible without using an elevator.

=item i / info

Does not restrict the requested connections. However, this option causes
B<efa> to display additional accessibility information for each route part
(where available). When B<-x w> or B<-x l> do not return any connections,
using B<-x i> might be more helpful (though it cannot guarantee that any of
the results satisfy the respective type).

=item l / nf / low-platform

All vehicles must be low-platform ("Niederflur").

=item s / no-stairs

Transfers must be possible without stairs (e.g. via escalators/elevators or
ramps).

=item w / wheelchair

All vehicles must be wheelchair accessible.

=back

=back

=head1 EXIT STATUS

    0    Everything went well
    1    Invalid arguments, see error message
    2    Network error, unable to send request
    3    efa.vrr.de did not return any parsable data
    4    efa.vrr.de error: ambiguous input
    5    efa.vrr.de error: no connections found
    10   Unknown Travel::Routing::DE::EFA error
    255  Other internal error

=head1 CONFIGURATION

None.

=head1 EXAMPLES

=over

=item efa Do Hbf MH Hbf

Look up a connection from Dortmund (Do) Hbf to ME<uuml>lheim (MH) Hbf

=item efa --include ice Essen Hbf Hamburg Dammtor

Look up a connection with long-distance trains

=item efa --arrive 18:00 -e zug,s-bahn -M E Wickenburgstr D Oststr

Look up a connection from Essen Wickenburgstr to DE<uuml>sseldorf Oststr.
Do not use any trains, make sure to arrive around 18:00 and print links to
maps of all interchange stations.

=item efa -s vvs Stuttgart Hbf Stuttgart Marienplatz

Use the VVS (Verkehrsverbund Stuttgart) EFA service to look up a connection.

=back

=head1 DEPENDENCIES

This script requires perl 5.10 (or higher) with the following modules:

=over

=item * Class::Accessor

=item * Exception::Class

=item * LWP::UserAgent

=item * XML::LibXML

=back

=head1 BUGS AND LIMITATIONS

The EFA backend is not able to calculate "two-way" routes, i.e. from -> via ->
to routes with from == to. If from and to are the same stop, it doesn't even
try to calculate a route ("we recommend walking instead"), if they are close to
each other it may or may not work.  Workaround: Request from -> via using the
normal four-argument efa invocation, read the time, use efa -t time via via to
to to request via -> to.

=head1 AUTHOR

Copyright (C) 2009-2018 by Daniel Friesel E<lt>derf@finalrewind.orgE<gt>

=head1 LICENSE

  0. You just DO WHAT THE FUCK YOU WANT TO.