maintenance: remove polyline code. polylines were added more than two years ago

		);

		$tx->commit;

	}

	# Add estimated polylines to journeys logged before 2020-01-28

	$tx = $db->begin;

	say 'Adding polylines to journeys logged before 2020-01-28';

	my $no_polyline

	  = $db->select( 'journeys', 'count(*) as count', { polyline_id => undef } )

	  ->hash;

	say "Checking $no_polyline->{count} journeys ...";

	for my $journey (

		$db->select( 'journeys', [ 'id', 'route' ], { polyline_id => undef } )

		->hashes->each )

	{

		# prior to v1.9.4, routes were stored as [["stop1"], ["stop2"], ...].

		# Nowadays, the common format is [["stop1", {}, null], ...].

		# entry[1] is non-empty only while checked in, entry[2] is non-null only

		# if the stop is unscheduled or has been cancelled.

		#

		# Here, we pretend to use the new format, as we're looking for

		# matching routes in more recent journeys.

		#

		# Note that journey->{route} is serialized JSON (i.e., a string).

		# It is not deserialized for performance reasons.

		$journey->{route}

		  =~ s/ (?<! additional ) (?<! cancelled ) "] /", {}, null]/gx;

		my $ref = $db->select(

			'journeys',

			[ 'id', 'polyline_id' ],

			{

				route       => $journey->{route},

				polyline_id => { '!=', undef },

				edited      => 0,

			},

			{ limit => 1 }

		)->hash;

		if ($ref) {

			my $rows = $db->update(

				'journeys',

				{ polyline_id => $ref->{polyline_id} },

				{ id          => $journey->{id} }

			)->rows;

			if ( $rows != 1 ) {

				say STDERR

"Database update returned $rows rows, expected 1. Rollback and abort.";

				exit(1);

			}

		}

		else {

			while ( my ( $old_name, $new_name )

				= each %{ $self->app->renamed_station } )

			{

				$journey->{route} =~ s{"\Q$old_name\E"}{"$new_name"};

			}

			my $ref = $db->select(

				'journeys',

				[ 'id', 'polyline_id' ],

				{

					route       => $journey->{route},

					polyline_id => { '!=', undef },

					edited      => 0,

				},

				{ limit => 1 }

			)->hash;

			if ($ref) {

				my $rows = $db->update(

					'journeys',

					{ polyline_id => $ref->{polyline_id} },

					{ id          => $journey->{id} }

				)->rows;

				if ( $rows != 1 ) {

					say STDERR

"Database update returned $rows rows, expected 1. Rollback and abort.";

					exit(1);

				}

			}

		}

	}

	my $remaining

	  = $db->select( 'journeys', 'count(*) as count', { polyline_id => undef } )

	  ->hash;

	say "Done! Remaining journeys without polyline: " . $remaining->{count};

	$tx->commit;

}

1;