From 32883b2a1b04a2ecb992b75836aa46b1d1da3249 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Max=20K=C3=A4nner?= <max.kaenner@gmail.com>
Date: Wed, 22 Jan 2025 01:17:11 +0100
Subject: [PATCH] spawn blocking task for simulations

---
 battlesnake/src/main.rs | 90 ++++++++++++++++++++++++-----------------
 1 file changed, 52 insertions(+), 38 deletions(-)

diff --git a/battlesnake/src/main.rs b/battlesnake/src/main.rs
index eb3c428..aa60bcc 100644
--- a/battlesnake/src/main.rs
+++ b/battlesnake/src/main.rs
@@ -82,46 +82,60 @@ async fn get_move(request: Json<Request>) -> response::Json<Response> {
     }
     info!("valid actions: {:?}", actions);
 
-    let mut action_data = [(0, 0); 4];
-    let mut total_simulations = 0;
-    let base_turns = board.turn();
-    while start.elapsed() < Duration::from_millis(250) {
-        let mut board = board.clone();
-        let action = *actions.choose(&mut thread_rng()).unwrap_or(&Direction::Up);
-        board.next_turn(&[(id, action)]);
-        let turns = board.simulate_random(|board| {
-            if board.num_snakes() == 0
-                || board.turn() > base_turns + u32::from(request.you.length) * 3
-            {
-                Some(board.turn())
-            } else {
-                None
-            }
+    tokio::task::spawn_blocking(move || {
+        let base_turns = board.turn();
+        let end_condition: &dyn Fn(&Board) -> Option<u32> = match &*request.game.ruleset.name {
+            "solo" => &|board: &Board| {
+                if board.num_snakes() == 0
+                    || board.turn() > base_turns + u32::from(request.you.length) * 3
+                {
+                    Some(board.turn())
+                } else {
+                    None
+                }
+            },
+            _ => &|board: &Board| {
+                if !board.alive(id) || board.turn() > base_turns + u32::from(request.you.length) * 3
+                {
+                    Some(board.turn())
+                } else {
+                    None
+                }
+            },
+        };
+
+        let mut action_data = [(0, 0); 4];
+        let mut total_simulations = 0;
+        while start.elapsed() < Duration::from_millis(250) {
+            let mut board = board.clone();
+            let action = *actions.choose(&mut thread_rng()).unwrap_or(&Direction::Up);
+            board.next_turn(&[(id, action)]);
+            let turns = board.simulate_random(end_condition);
+            let action_data = &mut action_data[usize::from(action)];
+            action_data.0 += turns - base_turns;
+            action_data.1 += 1;
+            total_simulations += 1;
+        }
+        debug!("action data: {action_data:?}");
+
+        let action = actions.into_iter().max_by_key(|action| {
+            let action_data = action_data[usize::from(*action)];
+            (action_data.0 / action_data.1, action_data.0 % action_data.1)
         });
-        let action_data = &mut action_data[usize::from(action)];
-        action_data.0 += turns - base_turns;
-        action_data.1 += 1;
-        total_simulations += 1;
-    }
-    debug!("action data: {action_data:?}");
 
-    let action = actions.into_iter().max_by_key(|action| {
-        let action_data = action_data[usize::from(*action)];
-        (action_data.0 / action_data.1, action_data.0 % action_data.1)
-    });
-
-    if let Some(action) = action {
-        let action_data = action_data[usize::from(action)];
-        let avg_turns = action_data.0 / action_data.1;
-        info!("found action {action:?} after {total_simulations} simulations with an average of {avg_turns} turns.");
-    } else {
-        warn!("unable to find a valid action");
-    }
-    info!("chose {action:?}");
-    response::Json(Response {
-        direction: action.unwrap_or(Direction::Up),
-        shout: None,
-    })
+        if let Some(action) = action {
+            let action_data = action_data[usize::from(action)];
+            let avg_turns = action_data.0 / action_data.1;
+            info!("found action {action:?} after {total_simulations} simulations with an average of {avg_turns} turns.");
+        } else {
+            warn!("unable to find a valid action");
+        }
+        info!("chose {action:?}");
+        response::Json(Response {
+            direction: action.unwrap_or(Direction::Up),
+            shout: None,
+        })
+    }).await.unwrap()
 }
 
 async fn end(request: Json<Request>) {