From b2115a4a7e45bf088a36f5af990b34adc1ae4625 Mon Sep 17 00:00:00 2001
From: Nick Pegg <nick@nickpegg.com>
Date: Thu, 10 Jul 2025 15:57:45 -0700
Subject: [PATCH] better split ace logic; more args

---
 src/main.rs | 41 +++++++++++++++++++++++++++--------------
 1 file changed, 27 insertions(+), 14 deletions(-)

diff --git a/src/main.rs b/src/main.rs
index 817c64e..1e6c48c 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -13,8 +13,8 @@ fn main() -> anyhow::Result<()> {
     // TODO: Use anyhow for error handling, get rid of unwraps
     let args = Args::parse();
     match args.mode {
-        Mode::Interactive => interactive_play(args.show_count),
-        Mode::OldMan => old_man(),
+        Mode::Interactive => interactive_play(args),
+        Mode::OldMan => old_man(args),
     }
 }
 
@@ -32,19 +32,23 @@ struct Args {
 
     #[arg(long, default_value_t = false)]
     show_count: bool,
+
+    #[arg(long, default_value_t = 6)]
+    decks: u8,
 }
 
-fn interactive_play(show_count: bool) -> anyhow::Result<()> {
+fn interactive_play(args: Args) -> anyhow::Result<()> {
     // TODO: Make a way to reset bank
     let term = Term::stdout();
     let mut bank: u32 = load_bank()?.unwrap_or(1_000);
 
-    let mut table = Table::new(6, bank).with_hit_on_soft_17();
+    let mut table = Table::new(args.decks, bank).with_hit_on_soft_17();
     let mut last_bet: Option<u32> = None;
 
     loop {
         println!("\nMoney in the bank: ${bank}");
-        if show_count {
+        // TODO: show normalized card count
+        if args.show_count {
             println!("Card count: {}", table.count());
             println!("Cards in shoe: {}", table.shoe_count());
         }
@@ -84,7 +88,7 @@ fn interactive_play(show_count: bool) -> anyhow::Result<()> {
         println!();
 
         let mut turn = table.deal_hand(bet);
-        let split_turn = interactive_play_turn(&mut turn, &mut table, show_count)?;
+        let split_turn = interactive_play_turn(&mut turn, &mut table, args.show_count)?;
         if split_turn.is_none() {
             table.dealers_turn()?;
             let result = table.results(turn)?;
@@ -92,7 +96,7 @@ fn interactive_play(show_count: bool) -> anyhow::Result<()> {
             print_result(&result);
         } else {
             let mut split_turn = split_turn.unwrap();
-            interactive_play_turn(&mut split_turn, &mut table, show_count)?;
+            interactive_play_turn(&mut split_turn, &mut table, args.show_count)?;
             table.dealers_turn()?;
             let result = table.results(turn)?;
             let split_result = table.results(split_turn)?;
@@ -215,7 +219,6 @@ fn print_result(result: &EndState) {
     println!("You got: ${}", result.returns);
 }
 
-// TODO: Make this use a lookup table, this if logic is gnarly
 fn basic_strategy(
     hand: &Hand,
     dealer_showing: &Card,
@@ -229,9 +232,8 @@ fn basic_strategy(
         // Got a pair, maybe should split
         // We check can_split right at the get-go, because if we can't we just follow the Hard
         // Total table.
-        let aces = hand.cards()[0].value == "A";
         match hand.value() {
-            12 if aces => PlayerChoice::Split,
+            12 if hand.has_ace() => PlayerChoice::Split,
             20 => PlayerChoice::Stand,
             18 => match dv {
                 2..=6 => PlayerChoice::Split,
@@ -353,7 +355,7 @@ fn basic_strategy_play_turn(
 /// addition to points/comps which he would use to eat brunch for free.
 ///
 /// Does this actually work, or was the driver full of it?
-fn old_man() -> anyhow::Result<()> {
+fn old_man(args: Args) -> anyhow::Result<()> {
     const START: u32 = 100_000;
     const PER_DAY: u32 = 400;
     const MIN_BET: u32 = 15;
@@ -361,7 +363,7 @@ fn old_man() -> anyhow::Result<()> {
     // Walk away when we're up by this much
     const MAX_WIN: u32 = 100;
     // Walk away when we're down by this much
-    const MAX_LOSS: u32 = MAX_WIN;
+    const MAX_LOSS: u32 = 100;
     // Run sim for this many days
     const DAYS: u16 = 30;
 
@@ -372,7 +374,7 @@ fn old_man() -> anyhow::Result<()> {
     for day in 1..=DAYS {
         bank -= PER_DAY;
 
-        let mut table = Table::new(6, PER_DAY).with_hit_on_soft_17();
+        let mut table = Table::new(args.decks, PER_DAY).with_hit_on_soft_17();
         let mut rounds = 0;
         while table.player_chips() > MIN_BET
             && table.player_chips() < (PER_DAY + MAX_WIN)
@@ -465,6 +467,17 @@ mod tests {
                 true,
             ),
             PlayerChoice::Stand,
-        )
+        );
+
+        // Always split aces
+        assert_eq!(
+            basic_strategy(
+                &Hand::from([("", "A"), ("", "A")].to_vec()),
+                &Card::from(("", "2")),
+                true,
+                true,
+            ),
+            PlayerChoice::Split,
+        );
     }
 }