Fix polyline view in journey detail view for ring lines

Partially resolves #268 -- in map views that are not specific to a single
journey, the polyline will still be wrong.

2 files changed, 16 insertions, 10 deletions

diff --git a/lib/Travelynx.pm b/lib/Travelynx.pm
index bf999bc..607b153 100755
--- a/lib/Travelynx.pm
+++ b/lib/Travelynx.pm
@@ -2829,10 +2829,14 @@ sub startup {
 				my $from_eva = $journey->{from_eva} // $journey->{dep_eva};
 				my $to_eva   = $journey->{to_eva}   // $journey->{arr_eva};
 
-				my $from_index
-				  = first_index { $_->[2] and $_->[2] == $from_eva } @polyline;
-				my $to_index
-				  = first_index { $_->[2] and $_->[2] == $to_eva } @polyline;
+				# poly_dep_index, poly_arr_index are only available for
+				# journeys that were processed by get_travel_distance
+				# beforehand. However, they are much less error-prone than this
+				# first_index / last_index kludge when it comes to ring lines.
+				my $from_index = $journey->{poly_dep_index}
+				  // first_index { $_->[2] and $_->[2] == $from_eva } @polyline;
+				my $to_index = $journey->{poly_arr_index}
+				  // first_index { $_->[2] and $_->[2] == $to_eva } @polyline;
 
 				# Work around inconsistencies caused by a multiple EVA IDs mapping to the same station name
 				if ( $from_index == -1 ) {
diff --git a/lib/Travelynx/Model/Journeys.pm b/lib/Travelynx/Model/Journeys.pm
index c0ba2a9..9efa365 100755
--- a/lib/Travelynx/Model/Journeys.pm
+++ b/lib/Travelynx/Model/Journeys.pm
@@ -1296,7 +1296,7 @@ sub get_travel_distance {
 
 	# Assumption: polyline entries are always [lat, lon] or [lat, lon, stop ID]
 	%seen = ();
-	for my $entry ( @{$polyline_ref} ) {
+	for my $entry ( @{ $polyline_ref // [] } ) {
 		if ( $entry->[2] ) {
 			$seen{ $entry->[2] } //= 1;
 			$entry->[3] = $seen{ $entry->[2] };
@@ -1311,17 +1311,19 @@ sub get_travel_distance {
 
 	# Just like the route, the polyline may contain the same stop more than
 	# once. So we need to select based on the seen counter.
-	my @polyline = after_incl {
+	my $poly_start = first_index {
 		$_->[2] and $_->[2] == $from_eva and $_->[3] == $route[0][2]{n}
 	}
 	@{ $polyline_ref // [] };
-	@polyline = before_incl {
+	my $poly_end = first_index {
 		$_->[2] and $_->[2] == $to_eva and $_->[3] == $route[-1][2]{n}
 	}
-	@polyline;
+	@{ $polyline_ref // [] };
 
-	# ensure that before_incl matched -- otherwise, @polyline is too long
-	if ( @polyline and $polyline[-1][2] == $to_eva ) {
+	if ( defined $poly_start and defined $poly_end ) {
+		$journey->{poly_dep_index} = $poly_start;
+		$journey->{poly_arr_index} = $poly_end;
+		my @polyline     = @{$polyline_ref}[ $poly_start .. $poly_end ];
 		my $prev_station = shift @polyline;
 		for my $station (@polyline) {
 			$distance_polyline += $geo->distance_metal(