better iter order

This reverts commit 5a52f2ab7a.

Cargo.lock

@@ -22,10 +22,9 @@ checksum = "c4512299f36f043ab09a583e57bceb5a5aab7a73db1805848e8fef3c9e8c78b3"
 
 [[package]]
 name = "card_game"
-version = "0.1.0"
+version = "0.2.0"
 dependencies = [
  "arrayvec",
- "rand",
 ]
 
 [[package]]
@@ -133,12 +132,22 @@ dependencies = [
  "rand",
 ]
 
+[[package]]
+name = "klondike-bench"
+version = "0.1.0"
+dependencies = [
+ "card_game",
+ "klondike",
+ "rand",
+]
+
 [[package]]
 name = "klondike-cli"
 version = "0.1.0"
 dependencies = [
  "card_game",
  "klondike",
+ "rand",
 ]
 
 [[package]]

Cargo.toml

@@ -2,6 +2,22 @@
 members = [
 	"card_game",
 	"klondike",
+	"klondike-bench",
 	"klondike-cli",
 ]
 resolver = "3"
+
+[workspace.dependencies]
+card_game = { version = "0.2.0", path = "card_game", registry = "Quaternions" }
+klondike = { version = "0.1.0", path = "klondike", registry = "Quaternions" }
+
+[workspace.lints.rust]
+# unsafe_code = "forbid"
+# missing_docs = "warn"
+# missing_debug_implementations = "warn"
+single_use_lifetimes = "warn"
+trivial_casts = "warn"
+unused_lifetimes = "warn"
+unused_qualifications = "warn"
+# variant_size_differences = "warn"
+unexpected_cfgs = "warn"

card_game/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "card_game"
-version = "0.1.0"
+version = "0.2.0"
 edition = "2024"
 repository = "https://git.aleshym.co/Quaternions/card_game"
 license = "MIT OR Apache-2.0"
@@ -10,4 +10,6 @@ keywords = ["card", "cards", "solitaire", "klondike"]
 
 [dependencies]
 arrayvec = "0.7.6"
-rand = { version = "0.10.1", default-features = false, features = ["thread_rng"] }
+
+[lints]
+workspace = true

card_game/README.md

@@ -1,37 +1,19 @@
 Card Game
 =========
 
-`card_game` is a library to implement card games.  Mainly interesting for the `Game` trait and the `Session` type.  Contains klondike as the reference implementation.
+`card_game` is a collection of algorithms, structs, and enums which are useful to implement card games.
 
 ## Example
 
 ```rust
-use card_game::Rng;
-use card_game::card_game::{Session, Game};
-use card_game::klondike::Klondike;
+use card_game::{Card, Deck, Rank, Stack, Suit};
 
-// create game session
-let game = Klondike::new_random_default();
-let mut session = Session::new(game);
+// create a full deck (unshuffled)
+let mut deck = Stack::full_deck(Deck::Deck1);
 
-// is winnable
-let is_winnable = session.is_winnable().is_some();
-
-// play game
-while let Some(instruction) = session.possible_instructions().next() {
-	session.process_instruction(instruction);
-}
-
-// did win
-let is_win = session.is_win();
-
-// print session history
-for (i, instruction) in session.history().iter().enumerate() {
-	println!("move {i} = {instruction:?}");
-}
-
-println!("is_winnable = {is_winnable}");
-println!("is_win = {is_win}");
+// inspect the top card
+let card = deck.pop().unwrap();
+assert_eq!(card, Card::new(Deck::Deck1, Suit::Diamonds, Rank::King));
 ```
 
 #### License

card_game/src/card_game.rs

@@ -1,314 +0,0 @@
-use core::ops::RangeBounds;
-
-// TODO: pub struct ValidInstruction<I>(I);
-pub trait Game {
-	type Instruction;
-	fn possible_instructions(&self) -> impl Iterator<Item = Self::Instruction> + use<Self>;
-	fn is_instruction_valid(&self, instruction: Self::Instruction) -> bool;
-	fn process_instruction(&mut self, instruction: Self::Instruction);
-	fn is_win(&self) -> bool;
-}
-
-#[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
-pub enum Suit {
-	Spades = 0b00,
-	Hearts = 0b01,
-	Clubs = 0b10,
-	Diamonds = 0b11,
-}
-impl Suit {
-	pub const SUITS: [Self; 4] = [Self::Spades, Self::Hearts, Self::Clubs, Self::Diamonds];
-	/// Is the suit red.
-	pub fn is_red(self) -> bool {
-		self as u8 & 0b01 != 0
-	}
-	/// Is the suit shape spikey.  (Bouba/kiki)
-	pub fn is_kiki(self) -> bool {
-		self as u8 & 0b10 != 0
-	}
-}
-
-#[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
-pub struct CardValue(u8);
-impl CardValue {
-	pub const ACE: Self = CardValue(1);
-	pub const TWO: Self = CardValue(2);
-	pub const THREE: Self = CardValue(3);
-	pub const FOUR: Self = CardValue(4);
-	pub const FIVE: Self = CardValue(5);
-	pub const SIX: Self = CardValue(6);
-	pub const SEVEN: Self = CardValue(7);
-	pub const EIGHT: Self = CardValue(8);
-	pub const NINE: Self = CardValue(9);
-	pub const TEN: Self = CardValue(10);
-	pub const JACK: Self = CardValue(11);
-	pub const QUEEN: Self = CardValue(12);
-	pub const KING: Self = CardValue(13);
-	pub fn get(self) -> u8 {
-		self.0
-	}
-	pub fn checked_add(self, offset: u8) -> Option<CardValue> {
-		let new_value = self.0.checked_add(offset)?;
-		if 13 < new_value {
-			None
-		} else {
-			Some(CardValue(new_value))
-		}
-	}
-	pub fn checked_sub(self, offset: u8) -> Option<CardValue> {
-		let new_value = self.0.checked_sub(offset)?;
-		if new_value < 1 {
-			None
-		} else {
-			Some(CardValue(new_value))
-		}
-	}
-}
-/// An identifier which specifies the deck id, suit, and card value.
-/// 2 bits for deck ID
-/// 2 bits for suit ID
-/// 4 bits for card Value
-/// TODO: better encoding for slightly more decks
-#[derive(Clone, Debug, Eq, Hash, PartialEq)]
-pub struct Card(u8);
-impl Card {
-	pub fn new(deck: u8, suit: Suit, CardValue(value): CardValue) -> Self {
-		Self(deck << 6 | (suit as u8) << 4 | value)
-	}
-	pub fn value(&self) -> CardValue {
-		let masked = self.0 & 0b1111;
-		CardValue(masked)
-	}
-	pub fn suit(&self) -> Suit {
-		let red = self.is_red();
-		let kiki = self.is_kiki();
-		match (kiki, red) {
-			(false, false) => Suit::Spades,
-			(false, true) => Suit::Hearts,
-			(true, false) => Suit::Clubs,
-			(true, true) => Suit::Diamonds,
-		}
-	}
-	/// Is the suit red.
-	pub fn is_red(&self) -> bool {
-		self.0 & 0b010000 != 0
-	}
-	/// Is the suit shape spikey.  (Bouba/kiki)
-	pub fn is_kiki(&self) -> bool {
-		self.0 & 0b100000 != 0
-	}
-	pub fn deck(&self) -> u8 {
-		self.0 >> 6
-	}
-}
-
-#[derive(Clone, Debug, Eq, Hash, PartialEq)]
-pub struct Stack<const CAP: usize>(arrayvec::ArrayVec<Card, CAP>);
-impl<const CAP: usize> Stack<CAP> {
-	pub const fn new() -> Self {
-		Self(arrayvec::ArrayVec::new_const())
-	}
-	pub fn take_range<R: RangeBounds<usize>>(&mut self, range: R) -> Self {
-		Stack::from_iter(self.drain(range))
-	}
-}
-impl Stack<52> {
-	/// Generate a full deck of cards with the specified deck id.
-	pub fn full_deck(deck: u8) -> Self {
-		let mut stack = arrayvec::ArrayVec::new();
-		for suit in Suit::SUITS {
-			for value in 1..=13 {
-				stack.push(Card::new(deck, suit, CardValue(value)));
-			}
-		}
-		Stack(stack)
-	}
-}
-impl<const CAP: usize> From<arrayvec::ArrayVec<Card, CAP>> for Stack<CAP> {
-	fn from(value: arrayvec::ArrayVec<Card, CAP>) -> Self {
-		Self(value)
-	}
-}
-impl<const CAP: usize> FromIterator<Card> for Stack<CAP> {
-	fn from_iter<T: IntoIterator<Item = Card>>(iter: T) -> Self {
-		Self(arrayvec::ArrayVec::from_iter(iter))
-	}
-}
-impl<const CAP: usize> core::ops::Deref for Stack<CAP> {
-	type Target = arrayvec::ArrayVec<Card, CAP>;
-	fn deref(&self) -> &Self::Target {
-		&self.0
-	}
-}
-impl<const CAP: usize> core::ops::DerefMut for Stack<CAP> {
-	fn deref_mut(&mut self) -> &mut Self::Target {
-		&mut self.0
-	}
-}
-impl<const CAP: usize> IntoIterator for Stack<CAP> {
-	type Item = Card;
-	type IntoIter = arrayvec::IntoIter<Card, CAP>;
-	fn into_iter(self) -> Self::IntoIter {
-		self.0.into_iter()
-	}
-}
-
-#[derive(Clone, Debug, Eq, Hash, PartialEq)]
-pub struct Pile<const DN: usize, const UP: usize> {
-	face_down: Stack<DN>,
-	face_up: Stack<UP>,
-}
-impl<const DN: usize, const UP: usize> Pile<DN, UP> {
-	pub fn new() -> Self {
-		Self {
-			face_down: Stack::new(),
-			face_up: Stack::new(),
-		}
-	}
-	pub fn new_face_down(stack: Stack<DN>) -> Self {
-		Self {
-			face_down: stack,
-			face_up: Stack::new(),
-		}
-	}
-	pub fn flip_up(&mut self) {
-		if let Some(card) = self.face_down.pop() {
-			self.face_up.push(card);
-		}
-	}
-	pub fn is_empty(&self) -> bool {
-		self.face_down.is_empty() && self.face_up.is_empty()
-	}
-	pub fn pop(&mut self) -> Option<Card> {
-		self.face_up.pop()
-	}
-	pub fn pop_flip_up(&mut self) -> Option<Card> {
-		let card = self.face_up.pop()?;
-		if self.face_up.is_empty() {
-			self.flip_up();
-		}
-		Some(card)
-	}
-	pub fn take_range<R: RangeBounds<usize>>(&mut self, range: R) -> Stack<UP> {
-		// if self.face_up.get(range).is_none() {
-		// 	return None;
-		// }
-		self.face_up.take_range(range)
-	}
-	pub fn take_range_flip_up<R: RangeBounds<usize>>(&mut self, range: R) -> Stack<UP> {
-		let cards = self.take_range(range);
-		if self.face_up.is_empty() {
-			self.flip_up();
-		}
-		cards
-	}
-	pub fn push(&mut self, card: Card) {
-		self.face_up.push(card);
-	}
-	pub fn extend<I: IntoIterator<Item = Card>>(&mut self, cards: I) {
-		self.face_up.extend(cards);
-	}
-	pub fn face_up(&self) -> &[Card] {
-		&self.face_up
-	}
-	pub fn face_down(&self) -> &[Card] {
-		&self.face_down
-	}
-}
-impl<const CAP: usize> Pile<CAP, CAP> {
-	pub fn flip_it_and_reverse_it(&mut self) {
-		self.swap_up_down();
-		self.face_down.reverse();
-	}
-	pub fn swap_up_down(&mut self) {
-		core::mem::swap(&mut self.face_up, &mut self.face_down);
-	}
-}
-
-#[derive(Clone, Debug, Eq, Hash, PartialEq)]
-pub struct Session<G: Game> {
-	seed: G,
-	state: G,
-	history: Vec<G::Instruction>,
-}
-impl<G: Game + Clone + Eq + core::hash::Hash> Session<G>
-where
-	G::Instruction: Clone + Eq + core::hash::Hash,
-{
-	pub fn new(state: G) -> Self {
-		Self {
-			seed: state.clone(),
-			state,
-			history: Vec::new(),
-		}
-	}
-	pub fn state(&self) -> &G {
-		&self.state
-	}
-	pub fn history(&self) -> &[G::Instruction] {
-		&self.history
-	}
-	pub fn is_winnable(&self) -> Option<Vec<G::Instruction>> {
-		let mut observed = std::collections::HashSet::new();
-		struct StateMachine<G, P, I> {
-			state: G,
-			possible_instructions_iter: P,
-			instruction: I,
-		}
-		let mut state = self.state.clone();
-		let mut it = state.possible_instructions();
-		let mut path = Vec::new();
-		'outer: while !state.is_win() {
-			observed.insert(state.clone());
-			for instruction in &mut it {
-				let mut next_state = state.clone();
-				next_state.process_instruction(instruction.clone());
-				if !observed.contains(&next_state) {
-					let possible_instructions_iter =
-						core::mem::replace(&mut it, next_state.possible_instructions());
-					let state = core::mem::replace(&mut state, next_state);
-					path.push(StateMachine {
-						state,
-						possible_instructions_iter,
-						instruction,
-					});
-					continue 'outer;
-				}
-			}
-			let Some(last_state) = path.pop() else {
-				return None;
-			};
-			state = last_state.state;
-			it = last_state.possible_instructions_iter;
-		}
-		Some(path.into_iter().map(|state| state.instruction).collect())
-	}
-	pub fn undo(&mut self) {
-		// replay the entire history of the game except one move
-		self.history.pop();
-		let mut state = self.seed.clone();
-		for instruction in self.history() {
-			state.process_instruction(instruction.clone());
-		}
-		self.state = state;
-	}
-}
-impl<G: Game> Game for Session<G>
-where
-	G::Instruction: Clone,
-{
-	type Instruction = G::Instruction;
-	fn possible_instructions(&self) -> impl Iterator<Item = Self::Instruction> + use<G> {
-		self.state.possible_instructions()
-	}
-	fn is_instruction_valid(&self, instruction: Self::Instruction) -> bool {
-		self.state.is_instruction_valid(instruction)
-	}
-	fn process_instruction(&mut self, instruction: Self::Instruction) {
-		self.history.push(instruction.clone());
-		self.state.process_instruction(instruction);
-	}
-	fn is_win(&self) -> bool {
-		self.state.is_win()
-	}
-}

card_game/src/lib.rs

@@ -1,7 +1,504 @@
-mod card_game;
-pub use card_game::*;
+// test readme
+#[doc = include_str!("../README.md")]
+#[cfg(doctest)]
+struct ReadmeDoctests;
 
-// // test readme
-// #[doc = include_str!("../README.md")]
-// #[cfg(doctest)]
-// struct ReadmeDoctests;
+use core::ops::RangeBounds;
+
+// TODO: pub struct ValidInstruction<I>(I);
+pub trait Game: Clone + core::fmt::Debug {
+	type Stats: Clone + core::fmt::Debug;
+	type Config: Clone + core::fmt::Debug;
+	type Instruction: Clone + core::fmt::Debug;
+	fn possible_instructions(&self) -> impl Iterator<Item = Self::Instruction> + use<Self>;
+	fn is_instruction_valid(&self, config: &Self::Config, instruction: Self::Instruction) -> bool;
+	fn process_instruction(
+		&mut self,
+		stats: &mut Self::Stats,
+		config: &Self::Config,
+		instruction: Self::Instruction,
+	);
+	fn is_win(&self) -> bool;
+}
+
+/// card_game supports up to 4 identifiably separate decks.
+#[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
+pub enum Deck {
+	Deck1 = 0b00,
+	Deck2 = 0b01,
+	Deck3 = 0b10,
+	Deck4 = 0b11,
+}
+impl Deck {
+	pub const fn new(deck: u8) -> Option<Self> {
+		use Deck::*;
+		Some(match deck {
+			0b00 => Deck1,
+			0b01 => Deck2,
+			0b10 => Deck3,
+			0b11 => Deck4,
+			_ => return None,
+		})
+	}
+}
+
+#[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
+pub enum Suit {
+	Spades = 0b00,
+	Hearts = 0b01,
+	Clubs = 0b10,
+	Diamonds = 0b11,
+}
+impl Suit {
+	pub const SUITS: [Self; 4] = [Self::Spades, Self::Hearts, Self::Clubs, Self::Diamonds];
+	pub const fn new(suit: u8) -> Option<Self> {
+		use Suit::*;
+		Some(match suit {
+			0b00 => Spades,
+			0b01 => Hearts,
+			0b10 => Clubs,
+			0b11 => Diamonds,
+			_ => return None,
+		})
+	}
+	/// Is the suit red.
+	pub const fn is_red(self) -> bool {
+		self as u8 & 0b01 != 0
+	}
+	/// Suit value is 2 bits, is_red is the low bit.
+	pub const fn suit_high_bit(self) -> bool {
+		self as u8 & 0b10 != 0
+	}
+}
+
+#[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
+pub enum Rank {
+	Ace = 1,
+	Two = 2,
+	Three = 3,
+	Four = 4,
+	Five = 5,
+	Six = 6,
+	Seven = 7,
+	Eight = 8,
+	Nine = 9,
+	Ten = 10,
+	Jack = 11,
+	Queen = 12,
+	King = 13,
+}
+impl Rank {
+	pub const RANKS: [Self; 13] = [
+		Self::Ace,
+		Self::Two,
+		Self::Three,
+		Self::Four,
+		Self::Five,
+		Self::Six,
+		Self::Seven,
+		Self::Eight,
+		Self::Nine,
+		Self::Ten,
+		Self::Jack,
+		Self::Queen,
+		Self::King,
+	];
+	pub const fn new(rank: u8) -> Option<Self> {
+		use Rank::*;
+		Some(match rank {
+			1 => Ace,
+			2 => Two,
+			3 => Three,
+			4 => Four,
+			5 => Five,
+			6 => Six,
+			7 => Seven,
+			8 => Eight,
+			9 => Nine,
+			10 => Ten,
+			11 => Jack,
+			12 => Queen,
+			13 => King,
+			_ => return None,
+		})
+	}
+	pub const fn checked_add(self, offset: u8) -> Option<Rank> {
+		match (self as u8).checked_add(offset) {
+			Some(rank) => Self::new(rank),
+			None => None,
+		}
+	}
+	pub const fn checked_sub(self, offset: u8) -> Option<Rank> {
+		match (self as u8).checked_sub(offset) {
+			Some(rank) => Self::new(rank),
+			None => None,
+		}
+	}
+}
+
+/// A card which specifies the deck id, suit, and card value.
+/// 2 bits for deck ID
+/// 2 bits for suit ID
+/// 4 bits for card Value
+#[derive(Clone, Debug, Eq, Hash, PartialEq)]
+pub struct Card(core::num::NonZeroU8);
+impl Card {
+	pub const fn new(deck: Deck, suit: Suit, rank: Rank) -> Self {
+		let packed = (deck as u8) << 6 | (suit as u8) << 4 | (rank as u8);
+		Self(core::num::NonZeroU8::new(packed).unwrap())
+	}
+	pub const fn rank(&self) -> Rank {
+		let masked = self.0.get() & 0b1111;
+		Rank::new(masked).unwrap()
+	}
+	pub const fn suit(&self) -> Suit {
+		let low_bit = self.is_red();
+		let high_bit = self.suit_high_bit();
+		match (high_bit, low_bit) {
+			(false, false) => Suit::Spades,
+			(false, true) => Suit::Hearts,
+			(true, false) => Suit::Clubs,
+			(true, true) => Suit::Diamonds,
+		}
+	}
+	/// Is the suit red.
+	pub const fn is_red(&self) -> bool {
+		self.0.get() & 0b010000 != 0
+	}
+	/// Suit value is 2 bits, is_red is the low bit.
+	pub const fn suit_high_bit(&self) -> bool {
+		self.0.get() & 0b100000 != 0
+	}
+	pub const fn deck(&self) -> Deck {
+		Deck::new(self.0.get() >> 6).unwrap()
+	}
+}
+
+#[derive(Clone, Debug, Default, Eq, Hash, PartialEq)]
+pub struct Stack<const CAP: usize>(arrayvec::ArrayVec<Card, CAP>);
+impl<const CAP: usize> Stack<CAP> {
+	pub const fn new() -> Self {
+		Self(arrayvec::ArrayVec::new_const())
+	}
+	pub fn take_range<R: RangeBounds<usize>>(&mut self, range: R) -> Self {
+		Stack::from_iter(self.drain(range))
+	}
+}
+impl Stack<52> {
+	/// Generate a full deck of cards with the specified deck id.
+	pub fn full_deck(deck: Deck) -> Self {
+		let mut stack = arrayvec::ArrayVec::new();
+		for suit in Suit::SUITS {
+			for rank in Rank::RANKS {
+				stack.push(Card::new(deck, suit, rank));
+			}
+		}
+		Stack(stack)
+	}
+}
+impl<const CAP: usize> From<arrayvec::ArrayVec<Card, CAP>> for Stack<CAP> {
+	fn from(value: arrayvec::ArrayVec<Card, CAP>) -> Self {
+		Self(value)
+	}
+}
+impl<const CAP: usize> FromIterator<Card> for Stack<CAP> {
+	fn from_iter<T: IntoIterator<Item = Card>>(iter: T) -> Self {
+		Self(arrayvec::ArrayVec::from_iter(iter))
+	}
+}
+impl<const CAP: usize> core::ops::Deref for Stack<CAP> {
+	type Target = arrayvec::ArrayVec<Card, CAP>;
+	fn deref(&self) -> &Self::Target {
+		&self.0
+	}
+}
+impl<const CAP: usize> core::ops::DerefMut for Stack<CAP> {
+	fn deref_mut(&mut self) -> &mut Self::Target {
+		&mut self.0
+	}
+}
+impl<const CAP: usize> IntoIterator for Stack<CAP> {
+	type Item = Card;
+	type IntoIter = arrayvec::IntoIter<Card, CAP>;
+	fn into_iter(self) -> Self::IntoIter {
+		self.0.into_iter()
+	}
+}
+
+/// A pile is a stack of face down cards and a stack of face up cards.
+#[derive(Clone, Debug, Default, Eq, Hash, PartialEq)]
+pub struct Pile<const DN: usize, const UP: usize> {
+	face_down: Stack<DN>,
+	face_up: Stack<UP>,
+}
+impl<const DN: usize, const UP: usize> Pile<DN, UP> {
+	pub const fn new() -> Self {
+		Self {
+			face_down: Stack::new(),
+			face_up: Stack::new(),
+		}
+	}
+	pub const fn new_face_down(stack: Stack<DN>) -> Self {
+		Self {
+			face_down: stack,
+			face_up: Stack::new(),
+		}
+	}
+	pub fn flip_up(&mut self) {
+		if let Some(card) = self.face_down.pop() {
+			self.face_up.push(card);
+		}
+	}
+	pub fn is_empty(&self) -> bool {
+		self.face_down.is_empty() && self.face_up.is_empty()
+	}
+	pub fn pop(&mut self) -> Option<Card> {
+		self.face_up.pop()
+	}
+	pub fn pop_flip_up(&mut self) -> Option<Card> {
+		let card = self.face_up.pop()?;
+		if self.face_up.is_empty() {
+			self.flip_up();
+		}
+		Some(card)
+	}
+	pub fn take_range<R: RangeBounds<usize>>(&mut self, range: R) -> Stack<UP> {
+		// if self.face_up.get(range).is_none() {
+		// 	return None;
+		// }
+		self.face_up.take_range(range)
+	}
+	pub fn take_range_flip_up<R: RangeBounds<usize>>(&mut self, range: R) -> Stack<UP> {
+		let cards = self.take_range(range);
+		if self.face_up.is_empty() {
+			self.flip_up();
+		}
+		cards
+	}
+	pub fn push(&mut self, card: Card) {
+		self.face_up.push(card);
+	}
+	pub fn extend<I: IntoIterator<Item = Card>>(&mut self, cards: I) {
+		self.face_up.extend(cards);
+	}
+	pub fn face_up(&self) -> &[Card] {
+		&self.face_up
+	}
+	pub fn face_down(&self) -> &[Card] {
+		&self.face_down
+	}
+}
+impl<const CAP: usize> Pile<CAP, CAP> {
+	pub fn flip_it_and_reverse_it(&mut self) {
+		self.swap_up_down();
+		self.face_down.reverse();
+	}
+	pub const fn swap_up_down(&mut self) {
+		core::mem::swap(&mut self.face_up, &mut self.face_down);
+	}
+}
+
+#[derive(Clone, Debug)]
+pub enum SessionInstruction<I> {
+	Undo,
+	InnerInstruction(I),
+}
+
+#[derive(Clone, Debug, Default)]
+pub struct SessionStats<S> {
+	inner_stats: S,
+	undos: usize,
+}
+impl<S> SessionStats<S> {
+	pub const fn stats(&self) -> &S {
+		&self.inner_stats
+	}
+	const fn increment_undos(&mut self) {
+		self.undos += 1;
+	}
+	pub const fn undos(&self) -> usize {
+		self.undos
+	}
+}
+
+#[derive(Clone, Debug)]
+pub struct Session<G: Game> {
+	stats: SessionStats<G::Stats>,
+	config: G::Config,
+	state: SessionState<G>,
+}
+#[derive(Clone, Debug)]
+pub struct StateSnapshot<G: Game> {
+	state: G,
+	instruction: G::Instruction,
+}
+impl<G: Game> StateSnapshot<G> {
+	pub const fn state(&self) -> &G {
+		&self.state
+	}
+	pub const fn instruction(&self) -> &G::Instruction {
+		&self.instruction
+	}
+}
+#[derive(Clone, Debug)]
+pub struct SessionState<G: Game> {
+	state: G,
+	history: Vec<StateSnapshot<G>>,
+}
+impl<G: Game + Clone> SessionState<G> {
+	fn new(state: G) -> Self {
+		Self {
+			state,
+			history: Vec::new(),
+		}
+	}
+}
+impl<G: Game> Session<G>
+where
+	G: Clone + Eq + core::hash::Hash,
+	G::Stats: Clone + Default,
+	G::Config: Clone,
+	G::Instruction: Clone + Eq + core::hash::Hash,
+{
+	pub fn new(state: G, config: G::Config) -> Self {
+		Self {
+			stats: SessionStats::default(),
+			config,
+			state: SessionState::new(state),
+		}
+	}
+	pub fn new_default(state: G) -> Self
+	where
+		G::Config: Default,
+	{
+		Self::new(state, Default::default())
+	}
+	pub const fn stats(&self) -> &SessionStats<G::Stats> {
+		&self.stats
+	}
+	pub const fn state(&self) -> &G {
+		&self.state.state
+	}
+	pub const fn config(&self) -> &G::Config {
+		&self.config
+	}
+	pub fn history(&self) -> &[StateSnapshot<G>] {
+		&self.state.history
+	}
+	pub fn undo(&mut self) {
+		self.state
+			.process_instruction(&mut self.stats, &self.config, SessionInstruction::Undo)
+	}
+	pub fn possible_instructions(&self) -> impl Iterator<Item = G::Instruction> + use<G> {
+		self.state.state.possible_instructions()
+	}
+	pub fn process_instruction(&mut self, instruction: G::Instruction) {
+		self.state.process_instruction(
+			&mut self.stats,
+			&self.config,
+			SessionInstruction::InnerInstruction(instruction),
+		)
+	}
+	pub fn is_win(&self) -> bool {
+		self.state.is_win()
+	}
+	pub fn is_winnable(&self) -> Option<Vec<StateSnapshot<G>>> {
+		let mut state_moves = std::collections::HashMap::new();
+		let mut state = self.clone();
+		let mut i: u64 = 0;
+		while !state.is_win() {
+			// Continue existing iterator if it exists
+			let it = state_moves
+				.entry(state.state().clone())
+				.or_insert_with(|| state.state().possible_instructions());
+
+			// Run one possible move
+			if let Some(instruction) = it.next() {
+				state.process_instruction(instruction);
+				continue;
+			}
+
+			// No more moves. If we can't undo we're done
+			if state.history().is_empty() {
+				return None;
+			} else {
+				state.undo();
+			}
+		}
+
+		// history includes cycles
+		let mut state_index: std::collections::HashMap<_, _> = state
+			.history()
+			.iter()
+			.enumerate()
+			.map(|(i, snapshot)| (snapshot.state().clone(), i))
+			.collect();
+
+		// find the longest range where the start and end are the same state
+		while let Some(longest_range) = state
+			.history()
+			.iter()
+			.enumerate()
+			.filter_map(|(index, snapshot)| {
+				let &last_index = state_index.get(snapshot.state())?;
+				let longness = last_index - index;
+				(longness != 0).then_some(index..last_index)
+			})
+			.max_by_key(|range| range.len())
+		{
+			state.state.history.drain(longest_range);
+			for (i, snapshot) in state.history().iter().enumerate() {
+				state_index.insert(snapshot.state().clone(), i);
+			}
+		}
+
+		Some(state.state.history)
+	}
+}
+impl<G: Game> Game for SessionState<G>
+where
+	G::Stats: Default,
+{
+	type Stats = SessionStats<G::Stats>;
+	type Config = G::Config;
+	type Instruction = SessionInstruction<G::Instruction>;
+	fn possible_instructions(&self) -> impl Iterator<Item = Self::Instruction> + use<G> {
+		self.state
+			.possible_instructions()
+			.map(SessionInstruction::InnerInstruction)
+	}
+	fn is_instruction_valid(&self, config: &Self::Config, instruction: Self::Instruction) -> bool {
+		match instruction {
+			SessionInstruction::Undo => !self.history.is_empty(),
+			SessionInstruction::InnerInstruction(instruction) => {
+				self.state.is_instruction_valid(config, instruction)
+			}
+		}
+	}
+	fn process_instruction(
+		&mut self,
+		stats: &mut Self::Stats,
+		config: &Self::Config,
+		instruction: Self::Instruction,
+	) {
+		match instruction {
+			SessionInstruction::Undo => {
+				if let Some(snapshot) = self.history.pop() {
+					self.state = snapshot.state;
+					stats.increment_undos();
+				}
+			}
+			SessionInstruction::InnerInstruction(instruction) => {
+				self.history.push(StateSnapshot {
+					state: self.state.clone(),
+					instruction: instruction.clone(),
+				});
+				self.state
+					.process_instruction(&mut stats.inner_stats, config, instruction);
+			}
+		}
+	}
+	fn is_win(&self) -> bool {
+		self.state.is_win()
+	}
+}

klondike-bench/Cargo.toml

@@ -0,0 +1,12 @@
+[package]
+name = "klondike-bench"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+card_game.workspace = true
+klondike.workspace = true
+rand = { version = "0.10.1", default-features = false }
+
+[lints]
+workspace = true

klondike-bench/src/main.rs

@@ -0,0 +1,46 @@
+use card_game::Game;
+use klondike::{Klondike, KlondikeConfig, KlondikeStats, Rng};
+
+const MAX_MOVES: usize = 250;
+
+fn play_to_win(rng: &mut Rng) -> Option<KlondikeStats> {
+	// create game session
+	let mut game = Klondike::with_rng(rng);
+	let mut stats = KlondikeStats::new();
+	const CONFIG: KlondikeConfig = KlondikeConfig {
+		draw_stock: klondike::DrawStockConfig::DrawOne,
+	};
+	// play game a bit
+	while let Some(instruction) = game.get_auto_move()
+		&& !game.is_win()
+	{
+		// quit before 250 moves
+		if MAX_MOVES < stats.moves() + 1 {
+			return None;
+		}
+
+		game.process_instruction(&mut stats, &CONFIG, instruction);
+	}
+	game.is_win().then_some(stats)
+}
+fn main() {
+	use rand::SeedableRng;
+	let mut rng = Rng::seed_from_u64(0);
+	const GAMES: u32 = 1000;
+	let mut wins = 0;
+	let mut score_tally = [0usize; MAX_MOVES * 10 / 5];
+	let mut recycle_tally = [0usize; MAX_MOVES];
+	let mut moves_tally = [0usize; MAX_MOVES];
+	for _ in 0..GAMES {
+		if let Some(stats) = play_to_win(&mut rng) {
+			wins += 1;
+			score_tally[stats.score() / 5] += 1;
+			recycle_tally[stats.recycle_count()] += 1;
+			moves_tally[stats.moves()] += 1;
+		}
+	}
+	println!("score_tally={score_tally:?}");
+	println!("recycle_tally={recycle_tally:?}");
+	println!("moves_tally={moves_tally:?}");
+	println!("wins = {wins}/{GAMES} win_rate = {}%", wins * 100 / GAMES);
+}

klondike-cli/Cargo.toml

@@ -4,5 +4,9 @@ version = "0.1.0"
 edition = "2024"
 
 [dependencies]
-card_game = { version = "0.1.0", path = "../card_game" }
-klondike = { version = "0.1.0", path = "../klondike" }
+card_game.workspace = true
+klondike.workspace = true
+rand = { version = "0.10.1", default-features = false, features = ["thread_rng"] }
+
+[lints]
+workspace = true

klondike-cli/src/main.rs

@@ -1,20 +1,23 @@
-use card_game::{Card, Game, Pile, Session, Suit};
+use card_game::{Card, Game, Pile, Rank, Session, SessionStats, Suit};
 use klondike::{
-	DstFoundation, DstTableau, Foundation, Klondike, KlondikeInstruction, KlondikePile,
-	KlondikePileStack, SkipCards, Tableau, TableauStack,
+	DstFoundation, DstTableau, Foundation, Klondike, KlondikeConfig, KlondikeInstruction,
+	KlondikePile, KlondikePileStack, KlondikeStats, SkipCards, Tableau, TableauStack,
 };
 
+#[cfg(test)]
+mod test;
+
 use std::fmt::Display;
 struct Displayed<T>(T);
 
 impl Display for Displayed<&Card> {
 	fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-		match self.0.value().get() {
-			1 => write!(f, "A"),
-			11 => write!(f, "J"),
-			12 => write!(f, "Q"),
-			13 => write!(f, "K"),
-			other => write!(f, "{other}"),
+		match self.0.rank() {
+			Rank::Ace => write!(f, "A"),
+			Rank::Jack => write!(f, "J"),
+			Rank::Queen => write!(f, "Q"),
+			Rank::King => write!(f, "K"),
+			other => write!(f, "{}", other as u8),
 		}?;
 		match self.0.suit() {
 			Suit::Spades => write!(f, "♠"),
@@ -83,6 +86,19 @@ impl Display for Displayed<&Klondike> {
 	}
 }
 
+impl Display for Displayed<&SessionStats<KlondikeStats>> {
+	fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+		write!(
+			f,
+			"recycles: {} moves: {} undos: {} score:{}",
+			self.0.stats().recycle_count(),
+			self.0.stats().moves(),
+			self.0.undos(),
+			self.0.stats().score() as isize - self.0.undos() as isize * 15,
+		)
+	}
+}
+
 #[derive(Debug)]
 struct Invalid;
 struct Parsed<T>(T);
@@ -135,7 +151,7 @@ impl core::str::FromStr for SessionInstruction {
 			"new" | "n" => Self::New,
 			"undo" | "u" => Self::Undo,
 			"hint" | "h" => Self::Hint,
-			"auto" | "a" => Self::Auto,
+			"auto" | "a" | "" => Self::Auto,
 			"exit" => Self::Exit,
 			"s" => Self::Stock,
 			other => Self::Klondike(other.parse()?),
@@ -144,6 +160,7 @@ impl core::str::FromStr for SessionInstruction {
 }
 
 fn find_valid_instruction(
+	config: &KlondikeConfig,
 	state: &Klondike,
 	naive_instruction: NaiveInstruction,
 ) -> Option<KlondikeInstruction> {
@@ -173,7 +190,7 @@ fn find_valid_instruction(
 						});
 						let instruction =
 							KlondikeInstruction::DstTableau(DstTableau { tableau, src });
-						if state.is_instruction_valid(instruction) {
+						if state.is_instruction_valid(config, instruction) {
 							return Some(instruction);
 						}
 					}
@@ -191,18 +208,30 @@ fn find_valid_instruction(
 		_ => return None,
 	};
 	state
-		.is_instruction_valid(instruction)
+		.is_instruction_valid(config, instruction)
 		.then_some(instruction)
 }
 
 fn main() -> Result<(), std::io::Error> {
-	let mut session = Session::new(Klondike::new_random_default());
+	use rand::RngExt;
+	let mut rng = rand::rng();
+	// seed from cli argument
+	let mut seed = if let Some(seed) = std::env::args().skip(1).next() {
+		seed.parse().expect("Invalid u64 seed")
+	} else {
+		rng.random()
+	};
+	let mut session = Session::new_default(Klondike::with_seed(seed));
+	let mut input = String::new();
 	loop {
+		// display stats
+		println!("seed: {seed} ");
+		println!("{}", Displayed(session.stats()));
 		// display game
 		println!("{}", Displayed(session.state()));
 
 		// parse input
-		let mut input = String::new();
+		input.clear();
 		std::io::stdin().read_line(&mut input)?;
 		let Ok(instruction) = input.trim().parse() else {
 			println!("Invalid instruction.");
@@ -211,7 +240,10 @@ fn main() -> Result<(), std::io::Error> {
 
 		// run game
 		match instruction {
-			SessionInstruction::New => session = Session::new(Klondike::new_random_default()),
+			SessionInstruction::New => {
+				seed = rng.random();
+				session = Session::new_default(Klondike::with_seed(seed))
+			}
 			SessionInstruction::Undo => session.undo(),
 			SessionInstruction::Exit => break Ok(()),
 			SessionInstruction::Hint => {
@@ -220,33 +252,7 @@ fn main() -> Result<(), std::io::Error> {
 				}
 			}
 			SessionInstruction::Auto => {
-				fn useless_moves(instruction: &KlondikeInstruction) -> bool {
-					!matches!(
-						instruction,
-						// foundation -> foundation is a useless move
-						KlondikeInstruction::DstFoundation(DstFoundation {
-							src: KlondikePile::Foundation(_),
-							..
-						})
-						// Tableau -> Tableau when not revealing a new card is _usually_ a useless move
-						| KlondikeInstruction::DstTableau(DstTableau {
-							src: KlondikePileStack::Tableau(TableauStack {
-								skip_cards: SkipCards::Skip1
-									| SkipCards::Skip2 | SkipCards::Skip3
-									| SkipCards::Skip4 | SkipCards::Skip5
-									| SkipCards::Skip6 | SkipCards::Skip7
-									| SkipCards::Skip8 | SkipCards::Skip9
-									| SkipCards::Skip10 | SkipCards::Skip11
-									| SkipCards::Skip12,
-								..
-							}),
-							..
-						})
-					)
-				}
-				if let Some(instruction) =
-					session.possible_instructions().filter(useless_moves).next()
-				{
+				if let Some(instruction) = session.state().get_auto_move() {
 					session.process_instruction(instruction);
 				} else {
 					println!("No valid moves!");
@@ -257,7 +263,7 @@ fn main() -> Result<(), std::io::Error> {
 			}
 			SessionInstruction::Klondike(naive_instruction) => {
 				if let Some(instruction) =
-					find_valid_instruction(session.state(), naive_instruction)
+					find_valid_instruction(session.config(), session.state(), naive_instruction)
 				{
 					session.process_instruction(instruction);
 				} else {

klondike-cli/src/test.rs

@@ -0,0 +1,15 @@
+use card_game::Session;
+use klondike::Klondike;
+#[test]
+fn test_is_winnable() {
+	// is winnable
+	let is_winnable = Session::new_default(Klondike::with_seed(124)).is_winnable();
+	if let Some(win_moves) = is_winnable {
+		// for (i, ins) in win_moves.into_iter().enumerate() {
+		// 	println!("{i} = {:?}", ins.instruction());
+		// }
+		println!("Game is winnable with {} moves", win_moves.len());
+	} else {
+		println!("Game is not winnable");
+	}
+}

klondike/Cargo.toml

@@ -4,5 +4,8 @@ version = "0.1.0"
 edition = "2024"
 
 [dependencies]
-card_game = { version = "0.1.0", path = "../card_game" }
-rand = { version = "0.10.1", default-features = false, features = ["thread_rng"] }
+card_game.workspace = true
+rand = { version = "0.10.1", default-features = false, features = ["std_rng"] }
+
+[lints]
+workspace = true

klondike/LICENSE-APACHE

@@ -0,0 +1,176 @@
+                              Apache License
+                        Version 2.0, January 2004
+                     http://www.apache.org/licenses/
+
+TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+1. Definitions.
+
+   "License" shall mean the terms and conditions for use, reproduction,
+   and distribution as defined by Sections 1 through 9 of this document.
+
+   "Licensor" shall mean the copyright owner or entity authorized by
+   the copyright owner that is granting the License.
+
+   "Legal Entity" shall mean the union of the acting entity and all
+   other entities that control, are controlled by, or are under common
+   control with that entity. For the purposes of this definition,
+   "control" means (i) the power, direct or indirect, to cause the
+   direction or management of such entity, whether by contract or
+   otherwise, or (ii) ownership of fifty percent (50%) or more of the
+   outstanding shares, or (iii) beneficial ownership of such entity.
+
+   "You" (or "Your") shall mean an individual or Legal Entity
+   exercising permissions granted by this License.
+
+   "Source" form shall mean the preferred form for making modifications,
+   including but not limited to software source code, documentation
+   source, and configuration files.
+
+   "Object" form shall mean any form resulting from mechanical
+   transformation or translation of a Source form, including but
+   not limited to compiled object code, generated documentation,
+   and conversions to other media types.
+
+   "Work" shall mean the work of authorship, whether in Source or
+   Object form, made available under the License, as indicated by a
+   copyright notice that is included in or attached to the work
+   (an example is provided in the Appendix below).
+
+   "Derivative Works" shall mean any work, whether in Source or Object
+   form, that is based on (or derived from) the Work and for which the
+   editorial revisions, annotations, elaborations, or other modifications
+   represent, as a whole, an original work of authorship. For the purposes
+   of this License, Derivative Works shall not include works that remain
+   separable from, or merely link (or bind by name) to the interfaces of,
+   the Work and Derivative Works thereof.
+
+   "Contribution" shall mean any work of authorship, including
+   the original version of the Work and any modifications or additions
+   to that Work or Derivative Works thereof, that is intentionally
+   submitted to Licensor for inclusion in the Work by the copyright owner
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+   communication on electronic mailing lists, source code control systems,
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+   "Contributor" shall mean Licensor and any individual or Legal Entity
+   on behalf of whom a Contribution has been received by Licensor and
+   subsequently incorporated within the Work.
+
+2. Grant of Copyright License. Subject to the terms and conditions of
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+4. Redistribution. You may reproduce and distribute copies of the
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+       of the NOTICE file are for informational purposes only and
+       do not modify the License. You may add Your own attribution
+       notices within Derivative Works that You distribute, alongside
+       or as an addendum to the NOTICE text from the Work, provided
+       that such additional attribution notices cannot be construed
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+
+   You may add Your own copyright statement to Your modifications and
+   may provide additional or different license terms and conditions
+   for use, reproduction, or distribution of Your modifications, or
+   for any such Derivative Works as a whole, provided Your use,
+   reproduction, and distribution of the Work otherwise complies with
+   the conditions stated in this License.
+
+5. Submission of Contributions. Unless You explicitly state otherwise,
+   any Contribution intentionally submitted for inclusion in the Work
+   by You to the Licensor shall be under the terms and conditions of
+   this License, without any additional terms or conditions.
+   Notwithstanding the above, nothing herein shall supersede or modify
+   the terms of any separate license agreement you may have executed
+   with Licensor regarding such Contributions.
+
+6. Trademarks. This License does not grant permission to use the trade
+   names, trademarks, service marks, or product names of the Licensor,
+   except as required for reasonable and customary use in describing the
+   origin of the Work and reproducing the content of the NOTICE file.
+
+7. Disclaimer of Warranty. Unless required by applicable law or
+   agreed to in writing, Licensor provides the Work (and each
+   Contributor provides its Contributions) on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+   implied, including, without limitation, any warranties or conditions
+   of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+   PARTICULAR PURPOSE. You are solely responsible for determining the
+   appropriateness of using or redistributing the Work and assume any
+   risks associated with Your exercise of permissions under this License.
+
+8. Limitation of Liability. In no event and under no legal theory,
+   whether in tort (including negligence), contract, or otherwise,
+   unless required by applicable law (such as deliberate and grossly
+   negligent acts) or agreed to in writing, shall any Contributor be
+   liable to You for damages, including any direct, indirect, special,
+   incidental, or consequential damages of any character arising as a
+   result of this License or out of the use or inability to use the
+   Work (including but not limited to damages for loss of goodwill,
+   work stoppage, computer failure or malfunction, or any and all
+   other commercial damages or losses), even if such Contributor
+   has been advised of the possibility of such damages.
+
+9. Accepting Warranty or Additional Liability. While redistributing
+   the Work or Derivative Works thereof, You may choose to offer,
+   and charge a fee for, acceptance of support, warranty, indemnity,
+   or other liability obligations and/or rights consistent with this
+   License. However, in accepting such obligations, You may act only
+   on Your own behalf and on Your sole responsibility, not on behalf
+   of any other Contributor, and only if You agree to indemnify,
+   defend, and hold each Contributor harmless for any liability
+   incurred by, or claims asserted against, such Contributor by reason
+   of your accepting any such warranty or additional liability.
+
+END OF TERMS AND CONDITIONS

klondike/LICENSE-MIT

@@ -0,0 +1,23 @@
+Permission is hereby granted, free of charge, to any
+person obtaining a copy of this software and associated
+documentation files (the "Software"), to deal in the
+Software without restriction, including without
+limitation the rights to use, copy, modify, merge,
+publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software
+is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice
+shall be included in all copies or substantial portions
+of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
+ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
+TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
+PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
+SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
+IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.

klondike/README.md

@@ -0,0 +1,50 @@
+Klondike
+========
+
+`klondike` is a pure-logic implementation of Klondike using `card_game`.  Graphics not included.
+
+## Example
+
+```rust
+use card_game::Session;
+use klondike::Klondike;
+
+// create game session
+let game = Klondike::with_seed(123);
+let mut session = Session::new_default(game);
+
+// play game a bit
+while let Some(instruction) = session.state().get_auto_move() {
+	session.process_instruction(instruction);
+
+	// quit after 1000 moves
+	if 1000 < session.stats().stats().moves() {
+		break;
+	}
+}
+
+// did win
+let is_win = session.is_win();
+
+// print session history
+for (i, instruction) in session.history().iter().enumerate() {
+	println!("move {i} = {instruction:?}");
+}
+
+println!("is_win = {is_win}");
+```
+
+#### License
+
+<sup>
+Licensed under either of <a href="LICENSE-APACHE">Apache License, Version
+2.0</a> or <a href="LICENSE-MIT">MIT license</a> at your option.
+</sup>
+
+<br>
+
+<sub>
+Unless you explicitly state otherwise, any contribution intentionally submitted
+for inclusion in this crate by you, as defined in the Apache-2.0 license, shall
+be dual licensed as above, without any additional terms or conditions.
+</sub>

klondike/src/lib.rs

@@ -1,15 +1,60 @@
-pub type Rng = rand::rngs::ThreadRng;
+pub type Rng = rand::rngs::StdRng;
 
-use card_game::{Card, CardValue, Game, Pile, Stack};
+use card_game::{Card, Game, Pile, Rank, Stack};
 
-#[cfg(test)]
-mod test;
+// test readme
+#[doc = include_str!("../README.md")]
+#[cfg(doctest)]
+struct ReadmeDoctests;
 
-#[derive(Clone, Debug, Eq, Hash, PartialEq)]
-pub struct KlondikeConfig {}
-impl Default for KlondikeConfig {
-	fn default() -> Self {
-		KlondikeConfig {}
+#[derive(Clone, Copy, Debug, Default)]
+pub enum DrawStockConfig {
+	#[default]
+	DrawOne = 1,
+	DrawThree = 3,
+}
+
+#[derive(Clone, Debug, Default)]
+pub struct KlondikeConfig {
+	pub draw_stock: DrawStockConfig,
+}
+
+#[derive(Clone, Debug, Default)]
+pub struct KlondikeStats {
+	score: usize,
+	recycle_count: usize,
+	moves: usize,
+}
+impl KlondikeStats {
+	pub const fn new() -> Self {
+		KlondikeStats {
+			score: 0,
+			recycle_count: 0,
+			moves: 0,
+		}
+	}
+	pub const fn score(&self) -> usize {
+		self.score
+	}
+	pub const fn recycle_count(&self) -> usize {
+		self.recycle_count
+	}
+	pub const fn moves(&self) -> usize {
+		self.moves
+	}
+	/// A card was moved to a foundation.
+	const fn increment_score_foundation(&mut self) {
+		self.score += 10;
+	}
+	/// A card was moved from stock to tableau.
+	const fn increment_score_tableau(&mut self) {
+		self.score += 5;
+	}
+	const fn increment_recycle_count(&mut self) {
+		self.recycle_count += 1;
+	}
+	const fn increment_moves(&mut self) {
+		self.moves += 1;
 	}
 }
 
@@ -154,7 +199,7 @@ impl TableauStack {
 			});
 		}
 		if let Some(tableau) = tableau.next() {
-			let skip_cards = SkipCards::Skip0;
+			let skip_cards = SkipCards::ITER_BEGIN;
 			return Some(Self {
 				tableau,
 				skip_cards,
@@ -254,6 +299,16 @@ impl KlondikeInstruction {
 			Self::RotateStock => return None,
 		})
 	}
+	/// foundation -> foundation is a useless move
+	pub fn is_useless(&self) -> bool {
+		matches!(
+			self,
+			KlondikeInstruction::DstFoundation(DstFoundation {
+				src: KlondikePile::Foundation(_),
+				..
+			})
+		)
+	}
 }
 
 const TABLEAUS: usize = 7;
@@ -311,7 +366,18 @@ impl KlondikeState {
 	pub const fn tableau7(&self) -> &Pile<6, 13> {
 		&self.tableau7
 	}
-	pub fn card(&self, src: KlondikePileStack) -> Option<&Card> {
+	pub fn is_tableau_face_down_empty(&self, tableau: Tableau) -> bool {
+		match tableau {
+			Tableau::Tableau1 => self.tableau1.face_down().is_empty(),
+			Tableau::Tableau2 => self.tableau2.face_down().is_empty(),
+			Tableau::Tableau3 => self.tableau3.face_down().is_empty(),
+			Tableau::Tableau4 => self.tableau4.face_down().is_empty(),
+			Tableau::Tableau5 => self.tableau5.face_down().is_empty(),
+			Tableau::Tableau6 => self.tableau6.face_down().is_empty(),
+			Tableau::Tableau7 => self.tableau7.face_down().is_empty(),
+		}
+	}
+	pub fn stack_bottom_card(&self, src: KlondikePileStack) -> Option<&Card> {
 		match src {
 			KlondikePileStack::Tableau(TableauStack {
 				tableau,
@@ -331,8 +397,8 @@ impl KlondikeState {
 			KlondikePileStack::Stock => self.stock.face_up().last(),
 		}
 	}
-	pub fn top_card(&self, src: KlondikePile) -> Option<&Card> {
-		match src {
+	pub fn top_card<S: Into<KlondikePile>>(&self, src: S) -> Option<&Card> {
+		match src.into() {
 			KlondikePile::Tableau(tableau) => match tableau {
 				Tableau::Tableau1 => self.tableau1.face_up().last(),
 				Tableau::Tableau2 => self.tableau2.face_up().last(),
@@ -366,8 +432,8 @@ impl KlondikeState {
 			KlondikePileStack::Stock => Stack::from_iter(self.stock.pop()),
 		}
 	}
-	fn take_top_card(&mut self, src: KlondikePile) -> Option<Card> {
-		match src {
+	fn take_top_card<S: Into<KlondikePile>>(&mut self, src: S) -> Option<Card> {
+		match src.into() {
 			KlondikePile::Tableau(tableau) => match tableau {
 				Tableau::Tableau1 => self.tableau1.pop_flip_up(),
 				Tableau::Tableau2 => self.tableau2.pop_flip_up(),
@@ -378,12 +444,18 @@ impl KlondikeState {
 				Tableau::Tableau7 => self.tableau7.pop_flip_up(),
 			},
 			KlondikePile::Foundation(foundation) => self.foundations[foundation as usize].pop(),
-			KlondikePile::Stock => self.stock.pop_flip_up(),
+			KlondikePile::Stock => self.stock.pop(),
 		}
 	}
-	fn extend<I: IntoIterator<Item = Card>>(&mut self, dst: KlondikePile, cards: I) {
-		match dst {
-			KlondikePile::Tableau(tableau) => match tableau {
+	fn extend_foundation<I: IntoIterator<Item = Card>>(
+		&mut self,
+		foundation: Foundation,
+		cards: I,
+	) {
+		self.foundations[foundation as usize].extend(cards)
+	}
+	fn extend_tableau<I: IntoIterator<Item = Card>>(&mut self, tableau: Tableau, cards: I) {
+		match tableau {
 			Tableau::Tableau1 => self.tableau1.extend(cards),
 			Tableau::Tableau2 => self.tableau2.extend(cards),
 			Tableau::Tableau3 => self.tableau3.extend(cards),
@@ -391,11 +463,6 @@ impl KlondikeState {
 			Tableau::Tableau5 => self.tableau5.extend(cards),
 			Tableau::Tableau6 => self.tableau6.extend(cards),
 			Tableau::Tableau7 => self.tableau7.extend(cards),
-			},
-			KlondikePile::Foundation(foundation) => {
-				self.foundations[foundation as usize].extend(cards)
-			}
-			KlondikePile::Stock => self.stock.extend(cards),
 		}
 	}
 	pub fn is_instruction_valid(&self, instruction: KlondikeInstruction) -> bool {
@@ -410,16 +477,16 @@ impl KlondikeState {
 			KlondikeInstruction::DstFoundation(dst_foundation) => {
 				// get the top cards
 				if let Some(src_card) = self.top_card(dst_foundation.src) {
-					match self.top_card(dst_foundation.foundation.into()) {
+					match self.top_card(dst_foundation.foundation) {
 						// destination card exists
 						Some(dst_card) => {
 							// suit matches?
 							src_card.suit() == dst_card.suit()
 							// value is +1?
-							&& dst_card.value().checked_add(1) == Some(src_card.value())
+							&& dst_card.rank().checked_add(1) == Some(src_card.rank())
 						}
 						// only ace is allowed to go onto empty foundation
-						None => src_card.value() == CardValue::ACE,
+						None => src_card.rank() == Rank::Ace,
 					}
 				} else {
 					false
@@ -428,17 +495,17 @@ impl KlondikeState {
 			// other = move to tableau
 			KlondikeInstruction::DstTableau(dst_tableau) => {
 				// get the cards
-				if let Some(src_card) = self.card(dst_tableau.src) {
-					match self.top_card(dst_tableau.tableau.into()) {
+				if let Some(src_card) = self.stack_bottom_card(dst_tableau.src) {
+					match self.top_card(dst_tableau.tableau) {
 						// destination card exists
 						Some(dst_card) => {
 							// red-ness is opposite?
 							src_card.is_red() != dst_card.is_red()
 							// value is -1?
-							&& dst_card.value().checked_sub(1) == Some(src_card.value())
+							&& dst_card.rank().checked_sub(1) == Some(src_card.rank())
 						}
 						// only king is allowed to go onto empty tableau
-						None => src_card.value() == CardValue::KING,
+						None => src_card.rank() == Rank::King,
 					}
 				} else {
 					false
@@ -466,21 +533,26 @@ impl Iterator for KlondikeIter {
 		instruction
 	}
 }
+#[test]
+fn test_klondike_iter() {
+	assert_eq!(KlondikeIter::new().count(), 721);
+}
 
 #[derive(Clone, Debug, Eq, Hash, PartialEq)]
 pub struct Klondike {
-	config: KlondikeConfig,
 	state: KlondikeState,
 }
 impl Klondike {
-	pub fn new_random_default() -> Self {
-		Self::new(Rng::default(), KlondikeConfig::default())
+	pub fn with_seed(seed: u64) -> Self {
+		use rand::SeedableRng;
+		let mut rng = Rng::seed_from_u64(seed);
+		Self::with_rng(&mut rng)
 	}
-	pub fn new(mut seed: Rng, config: KlondikeConfig) -> Self {
+	pub fn with_rng(rng: &mut Rng) -> Self {
 		// shuffle a new deck
-		let mut deck = Stack::full_deck(0);
+		let mut deck = Stack::full_deck(card_game::Deck::Deck1);
 		use rand::seq::SliceRandom;
-		deck.shuffle(&mut seed);
+		deck.shuffle(rng);
 		let mut deck = deck.into_iter();
 
 		// generate tableaus
@@ -512,43 +584,13 @@ impl Klondike {
 			tableau6,
 			tableau7,
 		};
-		Self { config, state }
+		Self { state }
 	}
 	pub const fn state(&self) -> &KlondikeState {
 		&self.state
 	}
-}
-
-impl Game for Klondike {
-	type Instruction = KlondikeInstruction;
-	fn possible_instructions(&self) -> impl Iterator<Item = Self::Instruction> + use<> {
-		let state = self.state.clone();
-		KlondikeIter::new().filter(move |&instruction| state.is_instruction_valid(instruction))
-	}
-	fn is_instruction_valid(&self, instruction: Self::Instruction) -> bool {
-		self.state.is_instruction_valid(instruction)
-	}
-	fn process_instruction(&mut self, instruction: Self::Instruction) {
-		match instruction {
-			// Reset the stock if it's empty
-			KlondikeInstruction::RotateStock => {
-				if self.state.stock.face_down().is_empty() {
-					self.state.stock.flip_it_and_reverse_it();
-				} else {
-					self.state.stock.flip_up();
-				}
-			}
-			KlondikeInstruction::DstFoundation(DstFoundation { src, foundation }) => {
-				let cards = self.state.take_top_card(src);
-				self.state.extend(foundation.into(), cards);
-			}
-			KlondikeInstruction::DstTableau(DstTableau { src, tableau }) => {
-				let cards = self.state.take_stack(src);
-				self.state.extend(tableau.into(), cards);
-			}
-		}
-	}
-	fn is_win(&self) -> bool {
+	/// Check if the game should be auto-completed
+	pub fn is_win_trivial(&self) -> bool {
 		// all face down cards empty means win
 		self.state.stock.face_down().is_empty()
 			&& self.state.tableau1.face_down().is_empty()
@@ -559,4 +601,105 @@ impl Game for Klondike {
 			&& self.state.tableau6.face_down().is_empty()
 			&& self.state.tableau7.face_down().is_empty()
 	}
+	fn instruction_priority(&self, instruction: &KlondikeInstruction) -> usize {
+		// 1 Move into foundation
+		// 2 T->T Move to reveal new card (moving a non-king to reveal empty tableau also counts)
+		// 3 Move from stock
+		// 4 Rotate stock
+		// 5 T->T Move not revealing new card
+		// 6 Move from foundation
+		match instruction {
+			KlondikeInstruction::DstFoundation(_) => 1,
+			&KlondikeInstruction::DstTableau(dst_tableau) => match dst_tableau.src {
+				KlondikePileStack::Tableau(TableauStack {
+					tableau,
+					skip_cards: SkipCards::Skip0,
+				}) if !self.state().is_tableau_face_down_empty(tableau)
+					|| self
+						.state()
+						.stack_bottom_card(dst_tableau.src)
+						.is_some_and(|card| card.rank() != Rank::King) =>
+				{
+					2
+				}
+				KlondikePileStack::Stock => 3,
+				KlondikePileStack::Tableau(_) => 5,
+				KlondikePileStack::Foundation(_) => 6,
+			},
+			KlondikeInstruction::RotateStock => 4,
+		}
+	}
+	pub fn iter(&self) -> impl Iterator<Item = KlondikeInstruction> + use<> {
+		let state = self.state.clone();
+		KlondikeIter::new().filter(move |&instruction| state.is_instruction_valid(instruction))
+	}
+	/// A single move that usually makes progress towards a winning game
+	pub fn get_auto_move(&self) -> Option<KlondikeInstruction> {
+		self.iter()
+			.filter(|ins| !ins.is_useless())
+			.min_by_key(|ins| self.instruction_priority(ins))
+	}
+	/// A list of possible moves with useless moves filtered out and sorted by a simple priority function
+	pub fn get_sorted_moves(&self) -> Vec<KlondikeInstruction> {
+		let mut useful_moves: Vec<_> = self.iter().filter(|ins| !ins.is_useless()).collect();
+		useful_moves.sort_by_key(|ins| self.instruction_priority(ins));
+		useful_moves
+	}
+}
+
+impl Game for Klondike {
+	type Stats = KlondikeStats;
+	type Config = KlondikeConfig;
+	type Instruction = KlondikeInstruction;
+	fn possible_instructions(&self) -> impl Iterator<Item = Self::Instruction> + use<> {
+		self.get_sorted_moves().into_iter()
+	}
+	fn is_instruction_valid(&self, _config: &Self::Config, instruction: Self::Instruction) -> bool {
+		self.state.is_instruction_valid(instruction)
+	}
+	fn process_instruction(
+		&mut self,
+		stats: &mut Self::Stats,
+		config: &Self::Config,
+		instruction: Self::Instruction,
+	) {
+		stats.increment_moves();
+		match instruction {
+			// Reset the stock if it's empty
+			KlondikeInstruction::RotateStock => {
+				if self.state.stock.face_down().is_empty() {
+					self.state.stock.flip_it_and_reverse_it();
+					stats.increment_recycle_count();
+				} else {
+					for _ in 0..config.draw_stock as usize {
+						self.state.stock.flip_up();
+					}
+				}
+			}
+			// Move a card from anywhere to a foundation
+			KlondikeInstruction::DstFoundation(DstFoundation { src, foundation }) => {
+				stats.increment_score_foundation();
+				let card = self.state.take_top_card(src);
+				self.state.extend_foundation(foundation, card);
+			}
+			// Move a stack of cards from anywhere to a tableau
+			KlondikeInstruction::DstTableau(DstTableau { src, tableau }) => {
+				if src == KlondikePileStack::Stock {
+					stats.increment_score_tableau();
+				}
+				let cards = self.state.take_stack(src);
+				self.state.extend_tableau(tableau, cards);
+			}
+		}
+	}
+	fn is_win(&self) -> bool {
+		// all foundations contain all ranks
+		self.state.foundations.iter().all(|foundation| {
+			foundation.len() == Rank::RANKS.len()
+				&& foundation
+					.iter()
+					.zip(Rank::RANKS)
+					.all(|(card, rank)| card.rank() == rank)
+		})
+	}
 }

klondike/src/test.rs

@@ -1,33 +0,0 @@
-use crate::Klondike;
-use card_game::{Game, Session};
-#[test]
-fn test_is_winnable() {
-	// is winnable
-	let is_winnable = Session::new(Klondike::new_random_default()).is_winnable();
-	println!("is_winnable = {is_winnable:?}");
-}
-#[test]
-fn test_klondike() {
-	// create game session
-	let game = Klondike::new_random_default();
-	let mut session = Session::new(game);
-
-	// is winnable
-	let is_winnable = session.is_winnable();
-	println!("is_winnable = {is_winnable:?}");
-
-	// play game
-	while let Some(instruction) = session.possible_instructions().next() {
-		session.process_instruction(instruction);
-	}
-
-	// did win
-	let is_win = session.is_win();
-
-	// print session history
-	for (i, instruction) in session.history().iter().enumerate() {
-		println!("move {i} = {instruction:?}");
-	}
-
-	println!("is_win = {is_win}");
-}