From 38e7772d4f78601ba570bfca8083989a9be91f36 Mon Sep 17 00:00:00 2001
From: Stephen Seo <seo.disparate@gmail.com>
Date: Thu, 10 Mar 2022 16:44:01 +0900
Subject: [PATCH] More AI tweaks

---
 front_end/src/ai.rs | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/front_end/src/ai.rs b/front_end/src/ai.rs
index 1c0d825..8640f5d 100644
--- a/front_end/src/ai.rs
+++ b/front_end/src/ai.rs
@@ -1,8 +1,9 @@
 use std::collections::BTreeMap;
 
 use crate::constants::{AI_EASY_MAX_CHOICES, AI_NORMAL_MAX_CHOICES, COLS, ROWS};
+use crate::game_logic::check_win_draw;
 use crate::random_helper::get_seeded_random;
-use crate::state::{BoardState, BoardType, Turn};
+use crate::state::{board_deep_clone, BoardState, BoardType, Turn};
 
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
 pub enum AIDifficulty {
@@ -190,6 +191,18 @@ fn get_utility_for_slot(player: Turn, slot: SlotChoice, board: &BoardType) -> Op
         }
     }
 
+    // check if placing a token here allows the opposing player to win
+    if idx >= COLS as usize {
+        let cloned_board = board_deep_clone(board);
+        cloned_board[idx].replace(player.into());
+        cloned_board[idx - (COLS as usize)].replace(player.get_opposite().into());
+        if let Some((state, _)) = check_win_draw(&cloned_board) {
+            if state == player.get_opposite().into() {
+                utility *= 0.1;
+            }
+        }
+    }
+
     Some(utility)
 }