iterator fixes

src/agent.rs

@@ -1,5 +1,5 @@
 use crate::{
-    board::{Board, BOARD_SIZE},
+    board::Board,
     piece::Piece,
 };
 use rand::prelude::*;
@@ -59,14 +59,7 @@ pub struct RandomAgent {
 
 impl Agent for RandomAgent {
     fn next_move(&mut self, board: &Board) -> Option<(usize, usize)> {
-        (0..BOARD_SIZE)
-            .flat_map(|i| {
-                (0..BOARD_SIZE)
-                    .map(|j| (i, j))
-                    .collect::<Vec<(usize, usize)>>()
-            })
-            .flat_map(|(i, j)| board.what_if(i, j, self.color).map(|_| (i, j)))
-            .choose(&mut rand::rng())
+        board.possible_moves(self.color).choose(&mut rand::rng())
     }
 
     fn name(&self) -> &'static str {

src/board.rs

@@ -74,6 +74,14 @@ impl Board {
         self
     }
 
+    pub fn possible_moves(&self, color: Piece) -> Box<dyn Iterator<Item = (usize, usize)> + '_> {
+        Box::new(
+            (0..BOARD_SIZE)
+                .flat_map(|i| (0..BOARD_SIZE).map(move |j| (i, j)))
+                .filter(move |(i, j)| self.what_if(*i, *j, color).is_some()),
+        )
+    }
+
     /// Returns a mutable reference to a place on the [`Board`]
     /// at (i, j)
     pub const fn get_mut(&mut self, i: usize, j: usize) -> &mut Option<Piece> {

src/complexagent.rs

@@ -1,8 +1,4 @@
-use crate::{
-    agent::Agent,
-    board::{Board, BOARD_SIZE},
-    piece::Piece,
-};
+use crate::{agent::Agent, board::Board, piece::Piece};
 
 pub struct ComplexAgent {
     color: Piece,
@@ -22,7 +18,10 @@ impl Move {
         if i == 0 {
             return;
         }
-        self.next_move = problem_space(&self.board, !self.color);
+
+        if self.next_move.is_empty() {
+            self.next_move = problem_space(&self.board, !self.color).collect();
+        }
         self.next_move
             .iter_mut()
             .for_each(|x| x.populate_next_moves(i - 1));
@@ -47,37 +46,33 @@ impl Move {
     }
 }
 
-fn problem_space(board: &Board, color: Piece) -> Vec<Move> {
-    (0..BOARD_SIZE)
-        .flat_map(|i| {
-            (0..BOARD_SIZE)
-                .map(|j| (i, j))
-                .collect::<Vec<(usize, usize)>>()
-        })
-        .flat_map(|(i, j)| board.what_if(i, j, color).map(|x| (i, j, x)))
-        .map(|(i, j, (board, captured))| Move {
-            i,
-            j,
-            captured,
-            color,
-            board,
-            next_move: Vec::new(),
-        })
-        .collect()
+fn problem_space(board: &Board, color: Piece) -> Box<dyn Iterator<Item = Move> + '_> {
+    Box::new(
+        board
+            .possible_moves(color)
+            .flat_map(move |(i, j)| board.what_if(i, j, color).map(|x| (i, j, x)))
+            .map(move |(i, j, (board, captured))| Move {
+                i,
+                j,
+                captured,
+                color,
+                board,
+                next_move: Vec::new(),
+            }),
+    )
 }
 
 impl Agent for ComplexAgent {
     fn next_move(&mut self, board: &Board) -> Option<(usize, usize)> {
         const LOOPS: usize = 5;
         problem_space(board, self.color)
-            .into_iter()
             .map(|mut x| {
                 x.populate_next_moves(LOOPS);
                 x
             })
             .map(|m| ((m.i, m.j), m.value(self.color)))
-            .max_by_key(|&(_, c)| c)
-            .map(|(x, _)| x)
+            .max_by_key(|a| a.1)
+            .map(|a| a.0)
     }
 
     fn name(&self) -> &'static str {

src/main.rs

@@ -1,5 +1,3 @@
-use agent::{ManualAgent, RandomAgent};
-use complexagent::ComplexAgent;
 use game::Game;
 use piece::Piece;
 
@@ -11,10 +9,10 @@ mod misc;
 mod piece;
 
 fn main() {
-    let player1 = ComplexAgent::new(Piece::Black);
-    // let player2 = ComplexAgent::new(Piece::White);
-    let player2 = ManualAgent::new(Piece::White);
-    // let player2 = RandomAgent::new(Piece::White);
+    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 mut game = Game::new(Box::new(player1), Box::new(player2));
     game.game_loop();
 }