X-Git-Url: http://git.scottworley.com/pluta-lesnura/blobdiff_plain/0f06fcb6b15f3b433e668200a1d91bd11cebbba8..c5e4b1eb46c33d636e95f3dbbbdf0bb15ce5d2ef:/src/lib.rs

diff --git a/src/lib.rs b/src/lib.rs
index c90799e..c46aa7d 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,6 +1,471 @@
+use rand::seq::SliceRandom;
+use rand::Rng;
+
+pub const NUM_RANKS: usize = 13;
+pub const NUM_SUITS: usize = 4;
+pub const NUM_JOKERS: usize = 2;
+pub const NUM_CARDS: usize = NUM_RANKS * NUM_SUITS + NUM_JOKERS;
+
+pub const STARTING_CARDS: u8 = 3;
+pub const STARTING_MAD_SCIENCE_TOKENS: i8 = 15;
+pub const STARTING_PROGRESS: i8 = -10;
+
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub struct Rank(u8);
+impl Rank {
+    #[must_use]
+    pub fn value(&self) -> u8 {
+        self.0 + 1
+    }
+    #[must_use]
+    pub fn is_face(&self) -> bool {
+        self.value() > 10
+    }
+    #[must_use]
+    pub fn random() -> Self {
+        Self(
+            rand::thread_rng()
+                .gen_range(0..NUM_RANKS)
+                .try_into()
+                .expect("Too many ranks?"),
+        )
+    }
+}
+
+#[derive(Clone, Copy, Eq, PartialEq)]
+pub struct Suit(u8);
+
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub struct Card(u8);
+impl Card {
+    #[must_use]
+    pub fn is_joker(&self) -> bool {
+        usize::from(self.0) >= NUM_RANKS * NUM_SUITS
+    }
+    #[must_use]
+    pub fn rank(&self) -> Option<Rank> {
+        (!self.is_joker()).then_some(Rank(self.0 >> 2))
+    }
+    #[must_use]
+    pub fn suit(&self) -> Option<Suit> {
+        (!self.is_joker()).then_some(Suit(self.0 & 3))
+    }
+}
+
+#[derive(Clone, Copy)]
+pub enum WithOrWithoutJokers {
+    WithJokers,
+    WithoutJokers,
+}
+
+#[must_use]
+pub fn deck(j: WithOrWithoutJokers) -> Vec<Card> {
+    let limit = u8::try_from(match j {
+        WithOrWithoutJokers::WithJokers => NUM_CARDS,
+        WithOrWithoutJokers::WithoutJokers => NUM_SUITS * NUM_RANKS,
+    })
+    .expect("Too many cards?");
+    (0..limit).map(Card).collect()
+}
+
+fn shuffle(cards: &mut Vec<Card>) {
+    cards.shuffle(&mut rand::thread_rng());
+}
+#[must_use]
+fn shuffled(mut cards: Vec<Card>) -> Vec<Card> {
+    shuffle(&mut cards);
+    cards
+}
+
+#[derive(Clone, Copy, Debug)]
+pub struct PathLength(Rank);
+impl PathLength {
+    #[must_use]
+    pub fn random() -> Self {
+        Self(Rank::random())
+    }
+}
+
+#[derive(Clone, Copy, Default)]
+pub struct PathLengthInfo(u16);
+impl PathLengthInfo {
+    #[must_use]
+    pub fn is_showing(&self, i: Rank) -> bool {
+        (self.0 >> i.0) & 1 == 1
+    }
+    fn reveal(&mut self, i: Rank) {
+        self.0 |= 1 << i.0;
+    }
+    pub fn reveal_random(&mut self, true_length: PathLength) -> Option<Rank> {
+        let showing = usize::try_from(self.0.count_ones()).expect("There aren't that many bits");
+        let not_showing = NUM_RANKS - showing;
+        if not_showing <= 1 {
+            return None;
+        }
+
+        let mut show = rand::thread_rng().gen_range(0..not_showing - 1);
+        for i in 0..NUM_RANKS {
+            let r = Rank(u8::try_from(i).expect("Too many cards?"));
+            if !self.is_showing(r) && r != true_length.0 {
+                if show == 0 {
+                    self.reveal(r);
+                    return Some(r);
+                }
+                show -= 1;
+            }
+        }
+        unreachable!()
+    }
+}
+
+#[derive(Default)]
+pub struct Discard {
+    cards: Vec<Card>,
+}
+impl Discard {
+    pub fn discard(&mut self, card: Card) {
+        self.cards.push(card);
+    }
+    #[must_use]
+    pub fn top(&self) -> Option<&Card> {
+        self.cards.last()
+    }
+    fn len(&self) -> usize {
+        self.cards.len()
+    }
+}
+
+pub struct Library {
+    cards: Vec<Card>,
+}
+impl Library {
+    #[must_use]
+    pub fn new(cards: Vec<Card>) -> Self {
+        Self { cards }
+    }
+    pub fn draw(&mut self, discard: &mut Discard) -> Option<Card> {
+        if self.cards.is_empty() {
+            if let Some(top_discard) = discard.cards.pop() {
+                std::mem::swap(&mut self.cards, &mut discard.cards);
+                discard.discard(top_discard);
+                shuffle(&mut self.cards);
+            }
+        }
+        self.cards.pop()
+    }
+    fn len(&self) -> usize {
+        self.cards.len()
+    }
+}
+
+#[derive(Debug, Default)]
+pub struct Hand {
+    cards: Vec<Card>,
+}
+impl Hand {
+    fn add(&mut self, card: Card) {
+        self.cards.push(card);
+    }
+    fn remove(&mut self, card: Card) -> Result<(), &'static str> {
+        let i = self
+            .cards
+            .iter()
+            .position(|&e| e == card)
+            .ok_or("That card is not in your hand")?;
+        self.cards.swap_remove(i);
+        Ok(())
+    }
+    fn len(&self) -> usize {
+        self.cards.len()
+    }
+    fn random(&self) -> Option<&Card> {
+        self.cards.choose(&mut rand::thread_rng())
+    }
+    /// Make a new Hand that contains only cards of the requested suit
+    fn filter_by_suit(&self, suit: Suit) -> Self {
+        Self {
+            cards: self
+                .cards
+                .iter()
+                .filter(|c| c.suit().expect("I shouldn't have jokers in my hand") == suit)
+                .copied()
+                .collect(),
+        }
+    }
+}
+
+#[derive(Copy, Clone)]
+pub struct PlayerIndex(usize);
+impl PlayerIndex {
+    fn next(self, num_players: usize) -> Self {
+        Self((self.0 + 1) % num_players)
+    }
+}
+
+#[derive(Copy, Clone, Debug)]
+pub enum Play {
+    Play(Card),
+    Draw,
+}
+
+#[derive(Eq, PartialEq)]
+pub enum Phase {
+    Play,
+    Momentum,
+}
+
+#[derive(Debug)]
+pub enum GameOutcome {
+    Loss,
+    Win,
+}
+
+pub enum PlayOutcome {
+    Continue,
+    End(GameOutcome),
+}
+
+pub struct Game {
+    mad_science_tokens: i8,
+    progress: [i8; NUM_SUITS],
+    path_lengths: [PathLength; NUM_SUITS],
+    path_length_info: [PathLengthInfo; NUM_SUITS],
+    library: Library,
+    discard: Discard,
+    hands: Vec<Hand>,
+    turn: PlayerIndex,
+    phase: Phase,
+}
+impl Game {
+    pub fn add_player(&mut self) {
+        self.hands.push(Hand::default());
+        for _ in 0..STARTING_CARDS {
+            self.draw_for_player(PlayerIndex(self.hands.len() - 1));
+        }
+    }
+    /// # Errors
+    ///
+    /// Will return `Err` on invalid plays, like trying to draw during Play phase,
+    /// or trying to play a card that's not in your hand.
+    pub fn play(&mut self, play: Play) -> Result<PlayOutcome, &'static str> {
+        match play {
+            Play::Play(card) => self.play_card(card),
+            Play::Draw => self.draw_for_momentum(),
+        }
+    }
+
+    #[must_use]
+    pub fn current_player_hand(&self) -> &Hand {
+        &self.hands[self.turn.0]
+    }
+    fn player_hand_mut(&mut self, pi: PlayerIndex) -> &mut Hand {
+        &mut self.hands[pi.0]
+    }
+    fn current_player_hand_mut(&mut self) -> &mut Hand {
+        self.player_hand_mut(self.turn)
+    }
+
+    fn play_card(&mut self, card: Card) -> Result<PlayOutcome, &'static str> {
+        let momentum = self.apply_card(card)?;
+        if self.phase == Phase::Play && momentum {
+            self.phase = Phase::Momentum;
+            Ok(PlayOutcome::Continue)
+        } else {
+            Ok(self.end_of_turn())
+        }
+    }
+    fn draw_for_momentum(&mut self) -> Result<PlayOutcome, &'static str> {
+        if self.phase != Phase::Momentum {
+            return Err("You don't have momentum");
+        }
+        self.draw_for_player(self.turn);
+        Ok(self.end_of_turn())
+    }
+
+    fn draw_for_player(&mut self, pi: PlayerIndex) {
+        loop {
+            if let Some(card) = self.library.draw(&mut self.discard) {
+                if card.is_joker() {
+                    self.remove_mad_science_token();
+                    self.discard.discard(card);
+                } else {
+                    self.player_hand_mut(pi).add(card);
+                    break;
+                }
+            } else {
+                println!("Library ran out of cards");
+            }
+        }
+    }
+    fn remove_mad_science_token(&mut self) {
+        loop {
+            self.mad_science_tokens -= 1;
+            if self.mad_science_tokens != 0 {
+                break;
+            }
+        }
+    }
+    fn make_progress(&mut self, card: Card) {
+        let rank = card.rank().expect("Can't play jokers").0;
+        if rank < 6 {
+            let roll = rand::thread_rng().gen_range(1..=6);
+            if roll > rank {
+                self.remove_mad_science_token();
+            }
+        }
+        self.progress[usize::from(card.suit().expect("Can't play jokers").0)] += 1;
+    }
+    fn forecast(&mut self, card: Card) {
+        let suit = usize::from(card.suit().expect("Can't play jokers").0);
+        self.path_length_info[suit].reveal_random(self.path_lengths[suit]);
+    }
+    // Returns whether or not this play grants momentum
+    fn apply_card(&mut self, card: Card) -> Result<bool, &'static str> {
+        self.current_player_hand_mut().remove(card)?;
+        if card.rank().expect("Can't play jokers").is_face() {
+            self.forecast(card);
+        } else {
+            self.make_progress(card);
+        }
+        let suits_match = self
+            .discard
+            .top()
+            .map_or(false, |dis| dis.suit() == card.suit());
+        self.discard.discard(card);
+        Ok(suits_match)
+    }
+    fn valid(&self) -> bool {
+        108 == (self.library.len()
+            + self.discard.len()
+            + self.hands.iter().map(Hand::len).sum::<usize>())
+    }
+    fn roll_mad_science(&mut self) -> PlayOutcome {
+        let mut tokens = std::iter::from_fn(|| Some(rand::thread_rng().gen_bool(0.5)))
+            .take(usize::try_from(self.mad_science_tokens.abs()).expect("wat?"));
+        let keep_going = if self.mad_science_tokens > 0 {
+            tokens.any(|t| !t)
+        } else {
+            tokens.all(|t| !t)
+        };
+        if keep_going {
+            PlayOutcome::Continue
+        } else {
+            PlayOutcome::End(self.final_score())
+        }
+    }
+    fn final_score(&self) -> GameOutcome {
+        if self
+            .progress
+            .iter()
+            .zip(self.path_lengths.iter())
+            .any(|(&prog, len)| prog >= len.0.value().try_into().expect("wat?"))
+        {
+            GameOutcome::Win
+        } else {
+            GameOutcome::Loss
+        }
+    }
+    fn end_of_turn(&mut self) -> PlayOutcome {
+        assert!(self.valid());
+        self.phase = Phase::Play;
+        self.turn = self.turn.next(self.hands.len());
+        if self.turn.0 == 0 {
+            if let PlayOutcome::End(game_outcome) = self.roll_mad_science() {
+                return PlayOutcome::End(game_outcome);
+            }
+        }
+        self.draw_for_player(self.turn);
+        assert!(self.valid());
+        PlayOutcome::Continue
+    }
+}
+impl Default for Game {
+    fn default() -> Self {
+        Self {
+            mad_science_tokens: STARTING_MAD_SCIENCE_TOKENS,
+            progress: [STARTING_PROGRESS; NUM_SUITS],
+            path_lengths: std::iter::from_fn(|| Some(PathLength::random()))
+                .take(NUM_SUITS)
+                .collect::<Vec<_>>()
+                .try_into()
+                .expect("wat?"),
+            path_length_info: [PathLengthInfo::default(); NUM_SUITS],
+            library: Library::new(shuffled(
+                [
+                    deck(WithOrWithoutJokers::WithJokers),
+                    deck(WithOrWithoutJokers::WithJokers),
+                ]
+                .concat(),
+            )),
+            discard: Discard::default(),
+            hands: vec![],
+            turn: PlayerIndex(0),
+            phase: Phase::Play,
+        }
+    }
+}
+
+pub struct Player(Box<dyn FnMut(&Game) -> Play>);
+impl Player {
+    #[must_use]
+    pub fn new<T>(f: T) -> Self
+    where
+        T: FnMut(&Game) -> Play + 'static,
+    {
+        Self(Box::new(f))
+    }
+}
+
 #[must_use]
-pub fn add(left: usize, right: usize) -> usize {
-    left + right
+pub fn random_player(draw_chance: f64) -> Player {
+    Player(Box::new(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,
+                    }
+                }
+            }
+        }
+    }))
+}
+
+/// When available, make plays that grant momentum.
+#[must_use]
+pub fn momentum_player(mut fallback: Player) -> Player {
+    Player(Box::new(move |game: &Game| -> Play {
+        if game.phase == Phase::Play {
+            if let Some(suit) = game.discard.top().and_then(Card::suit) {
+                if let Some(card) = game.current_player_hand().filter_by_suit(suit).random() {
+                    return Play::Play(*card);
+                }
+            }
+        }
+        fallback.0(game)
+    }))
+}
+
+/// # Errors
+///
+/// Will return `Err` on invalid plays, like trying to draw during Play phase,
+/// or trying to play a card that's not in your hand.
+pub fn play(mut game: Game, mut players: Vec<Player>) -> Result<GameOutcome, &'static str> {
+    game.draw_for_player(game.turn);
+    loop {
+        if let PlayOutcome::End(game_outcome) = game.play(players[game.turn.0].0(&game))? {
+            return Ok(game_outcome);
+        }
+    }
 }
 
 #[cfg(test)]
@@ -8,8 +473,69 @@ mod tests {
     use super::*;
 
     #[test]
-    fn it_works() {
-        let result = add(2, 2);
-        assert_eq!(result, 4);
+    fn path_length_info_random_reveal() {
+        let length = PathLength(Rank(7));
+        let mut pli = PathLengthInfo::default();
+        for _ in 0..12 {
+            let old_pli = PathLengthInfo::clone(&pli);
+            match pli.reveal_random(length) {
+                None => panic!("Nothing revealed?"),
+                Some(r) => {
+                    assert!(!old_pli.is_showing(r));
+                    assert!(pli.is_showing(r));
+                }
+            }
+            assert_eq!(pli.0.count_ones(), 1 + old_pli.0.count_ones());
+        }
+        assert!(pli.reveal_random(length).is_none());
+    }
+
+    #[test]
+    fn test_deck() {
+        use WithOrWithoutJokers::*;
+        let d = deck(WithoutJokers);
+        let rank_sum: u32 = d
+            .iter()
+            .map(Card::rank)
+            .flatten()
+            .map(|r| u32::from(r.value()))
+            .sum();
+        assert_eq!(rank_sum, 364);
+        let _dj = deck(WithJokers);
+    }
+
+    #[test]
+    fn test_library() {
+        let mut lib = Library::new(vec![Card(7)]);
+        let mut dis = Discard::default();
+        dis.discard(Card(8));
+        dis.discard(Card(9));
+        assert_eq!(lib.draw(&mut dis), Some(Card(7)));
+        assert_eq!(lib.draw(&mut dis), Some(Card(8)));
+        assert_eq!(lib.draw(&mut dis), None);
+    }
+
+    #[test]
+    fn test_hand() {
+        let mut h = Hand::default();
+        assert!(h.remove(Card(4)).is_err());
+        h.add(Card(4));
+        assert!(h.remove(Card(3)).is_err());
+        assert!(h.remove(Card(4)).is_ok());
+        assert!(h.remove(Card(4)).is_err());
+    }
+
+    #[test]
+    fn test_game() {
+        for num_players in 1..10 {
+            let players: Vec<_> = std::iter::from_fn(|| Some(momentum_player(random_player(0.5))))
+                .take(num_players)
+                .collect();
+            let mut game = Game::default();
+            for _ in 0..num_players {
+                game.add_player();
+            }
+            assert!(play(game, players).is_ok());
+        }
     }
 }