From aa0622ab28e4bf320db9a2ff747e5004923e2570 Mon Sep 17 00:00:00 2001
From: Scott Worley <scottworley@scottworley.com>
Date: Tue, 18 Jul 2023 11:30:39 -0700
Subject: [PATCH] Configurable draw chance for momentum play

---
 src/lib.rs  | 35 ++++++++++++++++++-----------------
 src/main.rs | 11 ++++++++---
 2 files changed, 26 insertions(+), 20 deletions(-)

diff --git a/src/lib.rs b/src/lib.rs
index 19d003a..09bd5fb 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -405,22 +405,23 @@ impl Player {
     }
 }
 
-#[must_use]
-pub fn random_player(game: &Game) -> Play {
-    match game.phase {
-        Phase::Play => Play::Play(
-            *game
-                .current_player_hand()
-                .random()
-                .expect("I always have a card to play because I just drew one"),
-        ),
-        Phase::Momentum => {
-            if rand::thread_rng().gen_bool(0.5) {
-                Play::Draw
-            } else {
-                match game.current_player_hand().random() {
-                    Some(card) => Play::Play(*card),
-                    None => Play::Draw,
+pub fn random_player(draw_chance: f64) -> impl FnMut(&Game) -> Play {
+    move |game: &Game| -> Play {
+        match game.phase {
+            Phase::Play => Play::Play(
+                *game
+                    .current_player_hand()
+                    .random()
+                    .expect("I always have a card to play because I just drew one"),
+            ),
+            Phase::Momentum => {
+                if rand::thread_rng().gen_bool(draw_chance) {
+                    Play::Draw
+                } else {
+                    match game.current_player_hand().random() {
+                        Some(card) => Play::Play(*card),
+                        None => Play::Draw,
+                    }
                 }
             }
         }
@@ -500,7 +501,7 @@ mod tests {
     #[test]
     fn test_game() {
         for num_players in 1..10 {
-            let players: Vec<_> = std::iter::from_fn(|| Some(Player::new(random_player)))
+            let players: Vec<_> = std::iter::from_fn(|| Some(Player::new(random_player(0.5))))
                 .take(num_players)
                 .collect();
             let mut game = Game::default();
diff --git a/src/main.rs b/src/main.rs
index 16bb4f7..c7c1c92 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -12,6 +12,9 @@ struct Cli {
 enum Commands {
     /// Runs simulations
     Sim {
+        /// For momentum play, draw how often?  0-1
+        #[arg(short = 'p', long, default_value_t = 0.5)]
+        draw_chance: f64,
         /// How many games?
         #[arg(short = 'g', long, default_value_t = 1)]
         num_games: usize,
@@ -26,13 +29,15 @@ fn main() -> Result<(), &'static str> {
 
     match &cli.command {
         Some(Commands::Sim {
+            draw_chance,
             num_games,
             num_players,
         }) => {
             for _ in 0..*num_games {
-                let players: Vec<_> = std::iter::from_fn(|| Some(Player::new(random_player)))
-                    .take(*num_players)
-                    .collect();
+                let players: Vec<_> =
+                    std::iter::from_fn(|| Some(Player::new(random_player(*draw_chance))))
+                        .take(*num_players)
+                        .collect();
                 let mut game = Game::default();
                 for _ in 0..*num_players {
                     game.add_player();
-- 
2.44.1