From 7992aca8030364cf52f8bc8a6f3ebefc222b91c4 Mon Sep 17 00:00:00 2001
From: Simon Gardling <titaniumtown@proton.me>
Date: Tue, 11 Feb 2025 23:53:17 -0500
Subject: [PATCH] logic fixes and nits

---
 src/board.rs        | 79 +++++++++++++++++++++------------------------
 src/complexagent.rs | 18 +++++------
 src/main.rs         |  4 +--
 3 files changed, 46 insertions(+), 55 deletions(-)

diff --git a/src/board.rs b/src/board.rs
index 37253bc..6912ec0 100644
--- a/src/board.rs
+++ b/src/board.rs
@@ -4,7 +4,7 @@ use crate::{
 };
 use arrayvec::ArrayVec;
 use lazy_static::lazy_static;
-use std::{cmp::Ordering, fmt};
+use std::{cmp::Ordering, fmt, mem::MaybeUninit};
 
 pub const BOARD_SIZE: usize = 8;
 
@@ -19,50 +19,43 @@ type ChainCollection = ArrayVec<Chain, 8>;
 /// with each coordinate
 type PosMap<T> = ArrayVec<ArrayVec<T, BOARD_SIZE>, BOARD_SIZE>;
 
+fn gen_adj_lookup() -> PosMap<ChainCollection> {
+    (0..BOARD_SIZE)
+        .map(|i| {
+            (0..BOARD_SIZE)
+                .map(|j| {
+                    let (i_chain, j_chain) = (
+                        split_from(0..=BOARD_SIZE - 1, i),
+                        split_from(0..=BOARD_SIZE - 1, j),
+                    );
+
+                    let mut chains: ChainCollection = ArrayVec::new_const();
+
+                    chains.extend(
+                        i_chain
+                            .clone()
+                            .map(|range| range.map(move |i| (i, j)))
+                            .map(Iterator::collect),
+                    );
+                    chains.extend(
+                        j_chain
+                            .clone()
+                            .map(|range| range.map(move |j| (i, j)))
+                            .map(Iterator::collect),
+                    );
+
+                    // handle diagonals
+                    chains.extend(diag_raw(i_chain, j_chain).map(Iterator::collect));
+                    chains
+                })
+                .collect()
+        })
+        .collect()
+}
+
 lazy_static! {
     /// Precompute all possible chains for each position on the board
-    pub static ref ADJ_LOOKUP: PosMap<ChainCollection> = {
-        let mut output = ArrayVec::new();
-
-        // populate arrayvec as we index it [i][j]
-        for _ in 0..BOARD_SIZE {
-            let mut a = ArrayVec::new();
-            // [j]
-            for _ in 0..BOARD_SIZE {
-                a.push(ArrayVec::new());
-            }
-            output.push(a);
-        }
-
-        for (i, j) in Board::all_positions() {
-            let (i_chain, j_chain) = (
-                split_from(0..=BOARD_SIZE - 1, i),
-                split_from(0..=BOARD_SIZE - 1, j),
-            );
-
-            let mut chains: ChainCollection = ArrayVec::new_const();
-
-            chains.extend(
-                i_chain
-                    .clone()
-                    .map(|range| range.map(move |i| (i, j)))
-                    .map(Iterator::collect),
-            );
-            chains.extend(
-                j_chain
-                    .clone()
-                    .map(|range| range.map(move |j| (i, j)))
-                    .map(Iterator::collect),
-            );
-
-            // handle diagonals
-            chains.extend(diag_raw(i_chain, j_chain).map(Iterator::collect));
-
-            output[i][j] = chains;
-        }
-
-        output
-    };
+    pub static ref ADJ_LOOKUP: PosMap<ChainCollection> = gen_adj_lookup();
 }
 
 #[derive(Copy, Clone, PartialEq, Eq)]
diff --git a/src/complexagent.rs b/src/complexagent.rs
index 74205e8..2e3ad0b 100644
--- a/src/complexagent.rs
+++ b/src/complexagent.rs
@@ -142,11 +142,8 @@ impl FutureMoves {
 
     fn compute_values(&mut self) {
         for depth in (0..=self.current_depth).rev() {
-            let nodes_at_depth: Vec<usize> = self
-                .arena
-                .iter()
-                .enumerate()
-                .filter_map(|(idx, node)| (self.depth_of(node.parent) == depth).then_some(idx))
+            let nodes_at_depth: Vec<usize> = (0..self.arena.len())
+                .filter(|&idx| self.depth_of(idx) == depth)
                 .collect();
 
             for idx in nodes_at_depth {
@@ -166,9 +163,10 @@ impl FutureMoves {
         }
     }
 
-    fn depth_of(&self, node_parent: Option<usize>) -> usize {
+    /// Given an index from `self.arena`, what depth is it at? 0-indexed
+    fn depth_of(&self, node_parent: usize) -> usize {
         let mut depth = 0;
-        let mut current = node_parent;
+        let mut current = Some(node_parent);
         while let Some(parent_idx) = current {
             depth += 1;
             current = self.arena[parent_idx].parent;
@@ -203,7 +201,7 @@ impl FutureMoves {
             })
             .inspect(|&root| {
                 self.current_root = Some(root);
-                self.current_depth = self.max_depth - self.depth_of(Some(root));
+                self.current_depth = self.max_depth - self.depth_of(root);
                 self.prune_unrelated();
             })
             .is_some()
@@ -254,8 +252,8 @@ pub struct ComplexAgent {
 }
 
 impl ComplexAgent {
-    pub fn new(color: Piece) -> Self {
-        const MAX_DEPTH: usize = 6;
+    pub const fn new(color: Piece) -> Self {
+        const MAX_DEPTH: usize = 8;
         Self {
             color,
             future_moves: FutureMoves::new(color, MAX_DEPTH),
diff --git a/src/main.rs b/src/main.rs
index 6506e54..5c9bb14 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -11,8 +11,8 @@ mod piece;
 fn main() {
     let player1 = complexagent::ComplexAgent::new(Piece::Black);
     // let player2 = complexagent::ComplexAgent::new(Piece::White);
-    // let player2 = agent::ManualAgent::new(Piece::White);
-    let player2 = agent::RandomAgent::new(Piece::White);
+    let player2 = agent::ManualAgent::new(Piece::White);
+    // let player2 = agent::RandomAgent::new(Piece::White);
     let mut game = Game::new(Box::new(player1), Box::new(player2));
     game.game_loop();
 }