From 3bd28451e9ca4509077c6f367a37a287a63e4f23 Mon Sep 17 00:00:00 2001
From: Julia Ryan <juliaryan3.14@gmail.com>
Date: Fri, 12 Sep 2025 00:45:48 -0700
Subject: [PATCH] wip incremental distance update

---
 src/gamestate.rs | 21 +++++++++++++++------
 src/main.rs      | 17 +++++++++--------
 src/pathfind.rs  | 31 +++++++++++++++++++++++++++++++
 3 files changed, 55 insertions(+), 14 deletions(-)

diff --git a/src/gamestate.rs b/src/gamestate.rs
index 62ff548..b49475e 100644
--- a/src/gamestate.rs
+++ b/src/gamestate.rs
@@ -201,12 +201,20 @@ impl Default for GameState {
 
 impl Display for GameState {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        let dm = GoalDistanceMap::new(&self.walls, self.current_player);
+        let d1 = GoalDistanceMap::new(&self.walls, PlayerIdentifier::P1);
+        let d2 = GoalDistanceMap::new(&self.walls, PlayerIdentifier::P2);
 
         writeln!(
             f,
-            "P1: {}, P2: {}\n",
-            self.p1.walls_left, self.p2.walls_left
+            "P1: {} walls, {} away from win",
+            self.p1.walls_left,
+            d1.at(self.p1.x(), self.p1.y())
+        )?;
+        writeln!(
+            f,
+            "P2: {} walls, {} away from win",
+            self.p2.walls_left,
+            d2.at(self.p2.x(), self.p2.y())
         )?;
         writeln!(f, "┏━━┬━━┬━━┬━━┬━━┬━━┬━━┬━━┬━━┓")?;
         for y in 0..9 {
@@ -237,11 +245,12 @@ impl Display for GameState {
                     write!(f, "{wall}")?;
                 }
                 let player = if self.p1.x() == x && self.p1.y() == y {
-                    "\x1b[1mP1\x1b[0m".to_string()
+                    "\x1b[1mP1\x1b[0m".to_owned()
                 } else if self.p2.x() == x && self.p2.y() == y {
-                    "\x1b[1mP2\x1b[0m".to_string()
+                    "\x1b[1mP2\x1b[0m".to_owned()
                 } else {
-                    format!("{:^2}", dm.at(x, y))
+                    // format!("{:^2}", dm.at(x, y))
+                    "  ".to_owned()
                 };
                 write!(f, "{player}")?;
             }
diff --git a/src/main.rs b/src/main.rs
index d41fa46..915ac73 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -81,6 +81,11 @@ impl Game<NUM_NEXT_STATES> for Quoridor {
         } else {
             self.state.walls.can_walk_between(x, y, x, y + 1)
         };
+        if self.state.current_player_state().walls_left == 0 {
+            if res[..128].iter().any(|x| *x) {
+                panic!("{res:?}")
+            }
+        }
         // TODO: detect jumps for the 4 directions and also blocked jumps for the 2 sides of the other pawn
         res
     }
@@ -90,7 +95,7 @@ impl Game<NUM_NEXT_STATES> for Quoridor {
     }
 
     fn play(&mut self, action: usize) {
-        if action <= 128 {
+        if action < 128 {
             self.state.current_player_state_mut().walls_left -= 1;
         }
         let mut set_block = |i: usize, vertical| {
@@ -171,23 +176,19 @@ fn main() -> Result<(), MctsError> {
     let mut mcts: Mcts<Quoridor, _> = Mcts::<Quoridor, _>::new();
     let evaluator = ProgressEvaluator;
 
-    for _ in 0..100 {
-        // Perform 100 MCTS iterations
-        for _ in 0..10_000 {
+    while g.get_result().is_none() {
+        for _ in 0..5000 {
             mcts.iterate(&evaluator)?;
         }
 
-        // Get the best action based on visit counts
         let (score, policy) = mcts.get_result();
-        println!("Best action score: {}, Policy: {:?}", score, policy);
 
-        // Play the best action and update the MCTS tree
         let best_action_index = policy
             .iter()
             .enumerate()
             .max_by(|&(_, &a), &(_, &b)| a.partial_cmp(&b).unwrap())
             .map(|(index, _)| index)
-            .unwrap_or(0); // Default to first action if policy is empty
+            .unwrap_or(0);
 
         // let mut x = policy.iter().enumerate().collect::<Vec<_>>();
         // x.sort_by(|&(_, &a), &(_, &b)| a.total_cmp(&b));
diff --git a/src/pathfind.rs b/src/pathfind.rs
index dea7707..a00f345 100644
--- a/src/pathfind.rs
+++ b/src/pathfind.rs
@@ -38,6 +38,37 @@ impl GoalDistanceMap {
         Self { distances: res }
     }
 
+    pub fn add_wall(&mut self, w: &mut WallState, x: u8, y: u8, vertical: bool) {
+        // TODO: we just realized that actually you have to search from the 4 invalidated
+        // nodes and then propagate back when you've found a distance that's minus 1 from a
+        // trusted node
+        w.place(x, y, vertical);
+        let invalidate = [(x, y), (x + 1, y), (x, y + 1), (x + 1, y + 1)];
+        for (x, y) in invalidate {
+            self.distances[y as usize][x as usize] = u8::MAX;
+        }
+        let mut todo = VecDeque::from(invalidate.map(|(x, y)| ((x, y), self.at(x, y))));
+        while let Some(((x, y), distance)) = todo.pop_front() {
+            if self.distances[y as usize][x as usize] == distance - 1 {
+                continue;
+            }
+            self.distances[y as usize][x as usize] = distance;
+
+            if x > 0 && w.can_walk_between(x, y, x - 1, y) {
+                todo.push_back(((x - 1, y), distance - 1));
+            }
+            if x < 8 && w.can_walk_between(x, y, x + 1, y) {
+                todo.push_back(((x + 1, y), distance - 1));
+            }
+            if y > 0 && w.can_walk_between(x, y, x, y - 1) {
+                todo.push_back(((x, y - 1), distance - 1));
+            }
+            if y < 8 && w.can_walk_between(x, y, x, y + 1) {
+                todo.push_back(((x, y + 1), distance - 1));
+            }
+        }
+    }
+
     pub fn at(&self, x: u8, y: u8) -> u8 {
         self.distances[y as usize][x as usize]
     }