whatever I did there

battlesnake/src/logic.rs

@@ -14,7 +14,7 @@ use log::info;
 use rand::seq::SliceRandom;
 use serde_json::{json, Value};
 
-use crate::{Battlesnake, Board, Direction, Game, Move};
+use crate::{Battlesnake, Board, Coord, Direction, Game, Move};
 
 impl Battlesnake {
     /// Check if moving the snake in `direction` is safe.
@@ -68,6 +68,46 @@ impl Battlesnake {
         }
         false
     }
+
+    #[must_use]
+    pub fn health_cost(&self, tile: Coord, game: &Game, board: &Board) -> i32 {
+        // we can't leave the board
+        if !((0..board.width).contains(&tile.x) && (0..board.height).contains(&tile.y)) {
+            return self.health;
+        }
+
+        // we can't move into other snakes
+        if board
+            .snakes
+            .iter()
+            .filter(|snake| {
+                !(game.ruleset.settings.squad.allow_body_collisions && self.squad == snake.squad)
+            })
+            .flat_map(|snake| snake.body.iter())
+            .any(|&coord| tile == coord)
+        {
+            return self.health;
+        }
+
+        // every step costs us one health point
+        let mut cost = 1;
+
+        // hazards increase the health loss
+        if board.hazards.iter().any(|&hazard| tile == hazard) {
+            cost += game.ruleset.settings.hazard_damage_per_turn;
+        }
+
+        // check for bigger snakes that can move into this square
+        for snake in board
+            .snakes
+            .iter()
+            .filter(|snake| snake.id != self.id && self.length <= snake.length)
+        {
+            let moves = enum_iterator::all().map(|dir| snake.head.move_to(dir));
+        }
+
+        cost
+    }
 }
 
 // info is called when you create your Battlesnake on play.battlesnake.com

battlesnake/src/main.rs

@@ -16,18 +16,15 @@ mod logic;
 // See https://docs.battlesnake.com/api
 
 #[derive(Debug, PartialEq, Eq, Hash, Clone, Copy, Deserialize, Serialize, Sequence)]
+#[serde(rename_all = "lowercase")]
 pub enum Direction {
     /// Move left (-x)
-    #[serde(rename = "left")]
     Left,
     /// Move up (+y)
-    #[serde(rename = "up")]
     Up,
     /// Move right (+x)
-    #[serde(rename = "right")]
     Right,
     /// Move down (-y)
-    #[serde(rename = "down")]
     Down,
 }