From dd236118fe184c8dec54c04ceb7524d04b3aa5e7 Mon Sep 17 00:00:00 2001
From: Simon Gardling <titaniumtown@proton.me>
Date: Sun, 23 Feb 2025 00:50:36 -0500
Subject: [PATCH] impl prune_bad_children

---
 src/logic/future_moves.rs | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/src/logic/future_moves.rs b/src/logic/future_moves.rs
index b44a28e..f1ecf25 100644
--- a/src/logic/future_moves.rs
+++ b/src/logic/future_moves.rs
@@ -305,11 +305,32 @@ impl FutureMoves {
     fn set_root_idx_raw(&mut self, idx: usize) {
         self.update_root_idx_raw(idx);
 
+        self.prune_bad_children();
         self.refocus_tree();
         self.extend_layers();
         self.compute_values(0..self.arena.len());
     }
 
+    fn prune_bad_children(&mut self) {
+        const BOTTOM_PERC: f32 = 20.0;
+        let Some(root) = self.current_root else {
+            return;
+        };
+
+        let mut children = self.arena[root].children.clone();
+
+        children.sort_by_key(|&i| -self.arena[i].value);
+        let start_len = ((children.len()) as f32 * (1.0 - BOTTOM_PERC)) as usize;
+        let drained = children.drain(start_len..);
+        println!("{}", drained.len());
+
+        for i in drained {
+            self.arena[i].parent = None;
+        }
+
+        self.arena[root].children = children;
+    }
+
     /// Rebuilds the Arena based on `self.current_root`, prunes unrelated nodes
     fn refocus_tree(&mut self) {
         let Some(root) = self.current_root else {