Introduced preferences struct

src/gtfs/structs.rs

@@ -1,6 +1,13 @@
-use std::collections::HashMap;
+use std::collections::{HashMap, HashSet};
+
+use gtfs_structures::{Agency, Calendar, CalendarDate, RawStopTime, RawTrip, Route, Stop, TimepointType};
+
+// This is to store the preferences for the GTFS(-R) side of the code.
+pub struct Preferences {
+    pub route_numbers: HashSet<String>,
+    pub stop_codes: HashSet<String>,
+}
 
-use gtfs_structures::{Agency, Calendar, CalendarDate, RawStopTime, RawTrip, Route, Stop};
 
 // The main GTFS struct. This is similar to (but not exactly) gtfs-structures::Gtfs because we don't need everything
 #[derive(Debug)]
@@ -20,3 +27,9 @@ pub struct Gtfs {
     /// Stop times for the chosen stops and the chosen routes
     pub stop_times: HashMap<(String, u32), RawStopTime>,
 }
+
+pub struct Arrival<'a> {
+    pub route: &'a Route,
+    pub stop: &'a Stop,
+    pub timepoint: &'a TimepointType,
+}