fix latency calculation

standard Duration can't go negative

battlesnake/src/logic.rs

@@ -125,18 +125,16 @@ pub fn get_move(game: &Game, turn: i32, board: &Board, you: &Battlesnake) -> Opt
         + game_info.calculation_time.lock().map_or_else(
             |_| Duration::from_millis(u64::from(game.timeout) / 2),
             |mut guard| {
-                let new_duration = *guard
+                let target_latency = game.timeout * 3 / 4;
-                    + Duration::from_millis(
+                let latency = you.latency.parse().unwrap_or_else(|e| {
-                        u64::from(game.timeout) * 7 / 8
+                    error!("Unable to parse latency: {e}");
-                            - you
+                    target_latency
-                                .latency
+                });
-                                .parse()
+                let last_computation_time = u32::try_from(guard.as_millis()).unwrap_or(0);
-                                .unwrap_or(u64::from(game.timeout) * 7 / 8),
+                let computation_time =
-                    );
+                    (last_computation_time + target_latency).saturating_sub(latency);
-                *guard = new_duration.clamp(
+                *guard =
-                    Duration::from_millis(1),
+                    Duration::from_millis(u64::from(computation_time.clamp(1, target_latency)));
-                    Duration::from_millis(u64::from(game.timeout) * 7 / 8),
-                );
                 *guard
             },
         );