Can get the size of the smallest unsunk boat

sea_battle_backend/src/data/current_game_status.rs

@@ -194,6 +194,19 @@ impl CurrentGameStatus {
         None
     }
 
+    /// Get the size of the smallest un-sunk boat
+    pub fn get_size_of_smallest_un_sunk_boat(&self) -> Option<usize> {
+        let mut boats_size = self.rules.boats_list();
+        boats_size.sort();
+
+        for boat in &self.opponent_map.sunk_boats {
+            let index = boats_size.iter().position(|b| *b == boat.len)?;
+            boats_size.remove(index);
+        }
+
+        boats_size.first().cloned()
+    }
+
     pub fn print_your_map(&self) {
         PrintableCurrentGameMapStatus(self.rules.clone(), self.your_map.clone()).print_map()
     }
@@ -292,4 +305,40 @@ mod test {
         assert!(next_fire.is_some());
         assert!(possible_next_strikes.contains(&next_fire.unwrap()))
     }
+
+    #[test]
+    fn get_size_of_smallest_unsunk_boat_start_of_game() {
+        let status = CurrentGameStatus::default();
+        let min_val = *status.rules.boats_list().iter().min().unwrap();
+        assert_eq!(min_val, status.get_size_of_smallest_un_sunk_boat().unwrap());
+    }
+
+    #[test]
+    fn get_size_of_smallest_unsunk_boat_bigger_boat_sunk() {
+        let mut status = CurrentGameStatus::default();
+        let min_val = *status.rules.boats_list().iter().min().unwrap();
+
+        status.opponent_map.sunk_boats.push(BoatPosition {
+            start: Coordinates::new(0, 0),
+            len: min_val + 1,
+            direction: BoatDirection::Left,
+        });
+        assert_eq!(min_val, status.get_size_of_smallest_un_sunk_boat().unwrap());
+    }
+
+    #[test]
+    fn get_size_of_smallest_unsunk_boat_smallest_boat_sunk() {
+        let mut status = CurrentGameStatus::default();
+        let mut boats_size = status.rules.boats_list();
+        boats_size.sort();
+        status.opponent_map.sunk_boats.push(BoatPosition {
+            start: Coordinates::new(0, 0),
+            len: boats_size[0],
+            direction: BoatDirection::Left,
+        });
+        assert_eq!(
+            boats_size[1],
+            status.get_size_of_smallest_un_sunk_boat().unwrap()
+        );
+    }
 }