working on game tracking

1 files changed, 461 insertions, 0 deletions

diff --git a/src/game.rs b/src/game.rs
new file mode 100644
index 0000000..6307843
--- /dev/null
+++ b/src/game.rs
@@ -0,0 +1,461 @@
+use std::fmt;
+
+#[derive(Clone, Copy)]
+pub struct Position {
+    pub x: u8,
+    pub y: u8,
+}
+impl fmt::Display for Position {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{:x}{}", 10 + self.x, self.y + 1)
+    }
+}
+
+#[derive(PartialEq, Clone, Copy)]
+pub enum Player {
+    Black,
+    White,
+}
+
+impl fmt::Display for Player {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(
+            f,
+            "{}",
+            match self {
+                Player::Black => "B",
+                Player::White => "W",
+            }
+        )
+    }
+}
+
+#[derive(PartialEq, Clone, Copy)]
+pub enum Stone {
+    Flat,
+    Standing,
+    Capstone,
+}
+
+impl fmt::Display for Stone {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(
+            f,
+            "{}",
+            match self {
+                Stone::Flat => "",
+                Stone::Standing => "S",
+                Stone::Capstone => "C",
+            }
+        )
+    }
+}
+
+#[derive(Clone, Copy)]
+pub enum Direction {
+    Up,
+    Down,
+    Left,
+    Right,
+}
+
+impl fmt::Display for Direction {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(
+            f,
+            "{}",
+            match self {
+                Direction::Up => "+",
+                Direction::Down => "-",
+                Direction::Left => "<",
+                Direction::Right => ">",
+            }
+        )
+    }
+}
+
+pub enum Action {
+    Place(Player, Position, Stone),
+    Move(Player, Position, Direction, Vec<u8>),
+}
+
+impl fmt::Display for Action {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match self {
+            Action::Place(player, pos, stone) => write!(f, "{}{}{}", pos, player, stone),
+            Action::Move(_, pos, direction, drops) => write!(
+                f,
+                "{}{}{}",
+                pos,
+                direction,
+                drops.into_iter().map(|q| q.to_string()).collect::<String>()
+            ),
+        }
+    }
+}
+
+#[derive(Clone, Copy)]
+pub struct Piece {
+    pub player: Player,
+    pub stone: Stone,
+}
+pub type Stack = Vec<Piece>;
+
+pub struct GameState {
+    size: u8,
+    black_flats: u8,
+    white_flats: u8,
+    black_capstones: u8,
+    white_capstones: u8,
+    board: Vec<Stack>,
+}
+
+// TODO: Generate all legal actions for a given player
+
+impl GameState {
+    pub fn get_size(&self) -> u8 {
+        self.size
+    }
+
+    pub fn copy(&self) -> GameState {
+        let mut copy = GameState {
+            size: self.size,
+            black_flats: self.black_flats,
+            white_flats: self.white_flats,
+            black_capstones: self.black_capstones,
+            white_capstones: self.white_capstones,
+            board: Vec::new(),
+        };
+        for i in 0..self.board.len() {
+            for j in 0..self.board[i].len() {
+                copy.board[i].push(self.board[i][j]);
+            }
+        }
+        copy
+    }
+
+    // Defaults to 5x5 if requested things are out of range
+    pub fn new(size: u8) -> GameState {
+        let (flats, caps) = match size {
+            3 => (10, 0),
+            4 => (15, 0),
+            6 => (30, 1),
+            7 => (40, 2),
+            8 => (50, 2),
+            _ => (21, 1),
+        };
+        GameState {
+            size: size,
+            black_flats: flats,
+            white_flats: flats,
+            black_capstones: caps,
+            white_capstones: caps,
+            board: {
+                let mut v: Vec<Stack> = Vec::new();
+                for _i in 0..size * size {
+                    v.push(Vec::new());
+                }
+                v
+            },
+        }
+    }
+
+    fn remaining_pieces(&self, player: &Player, stone: &Stone) -> u8 {
+        match player {
+            Player::Black => {
+                if *stone == Stone::Capstone {
+                    self.black_capstones
+                } else {
+                    self.black_flats
+                }
+            }
+            Player::White => {
+                if *stone == Stone::Capstone {
+                    self.white_capstones
+                } else {
+                    self.white_flats
+                }
+            }
+        }
+    }
+
+    fn within_bounds(&self, pos: &Position) -> bool {
+        if (pos.x < self.size) && (pos.y < self.size) {
+            true
+        } else {
+            false
+        }
+    }
+
+    pub fn query_square(&self, pos: &Position) -> Option<&Stack> {
+        if self.within_bounds(pos) {
+            self.board.get(self.pos_to_idx(pos))
+        } else {
+            None
+        }
+    }
+
+    fn pos_to_idx(&self, pos: &Position) -> usize {
+        let y: usize = pos.y as usize;
+        let x: usize = pos.x as usize;
+        x + y * (self.size as usize)
+    }
+
+    // Unconditional and so could lead to invalid state, but private
+    fn place_stone(&self, player: Player, pos: &Position, stone: Stone) -> GameState {
+        let mut copy = self.copy();
+        let idx = self.pos_to_idx(&pos);
+        copy.board[idx].push(Piece {
+            player: player,
+            stone: stone,
+        });
+        copy
+    }
+
+    fn move_stack(&self, pos: &Position, direction: Direction, drops: &Vec<u8>) -> GameState {
+        let mut copy = self.copy();
+        let mut pos_new = Position { x: pos.x, y: pos.y };
+        let stack: &Stack = &self.board[self.pos_to_idx(pos)];
+
+        let mut k = 0;
+        for &d in drops {
+            let idx = copy.pos_to_idx(&pos_new);
+            for i in 0..d {
+                copy.board[idx].push(stack[(k + i) as usize]);
+            }
+            k += d;
+            match direction {
+                Direction::Up => pos_new.y + 1 >= self.size,
+                Direction::Down => pos_new.y == 0,
+                Direction::Left => pos_new.x + 1 >= self.size,
+                Direction::Right => pos_new.x == 0,
+            };
+        }
+        copy
+    }
+}
+
+pub struct Game<L>
+where
+    L: Fn(String),
+{
+    size: u8,
+    white_player_name: String,
+    black_player_name: String,
+    actions: Vec<Action>,
+    states: Vec<GameState>,
+    log: L,
+}
+
+impl<L: Fn(String)> Game<L> {
+    fn new(size: u8, white_player_name: &str, black_player_name: &str, log: L) -> Game<L> {
+        let size = if (size <= 3) || (size >= 8) {
+            (log)(format!(
+                "Warning: the requested game size of {}x{} is not supported, defaulting to 5x5.",
+                size, size
+            ));
+            5
+        } else {
+            size
+        };
+        Game {
+            size: size,
+            white_player_name: white_player_name.to_string(),
+            black_player_name: black_player_name.to_string(),
+            turn: 0,
+            states: vec![GameState::new(size)],
+            actions: Vec::new(),
+            log: log,
+        }
+    }
+
+    pub fn get_size(&self) -> u8 {
+        self.size
+    }
+
+    fn is_legal_place(&self, player: &Player, pos: &Position, stone: &Stone) -> bool {
+        if let Some(state) = self.states.last() {
+            /* In order to legally place a piece:
+            1. The desired square must be empty
+            2. The player must have sufficient pieces
+             */
+            if state.within_bounds(pos) {
+                if let Some(stack) = &state.board.get(state.pos_to_idx(pos)) {
+                    if stack.len() > 0 {
+                        (self.log)(format!("{} is already occupied.", pos));
+                        false
+                    } else if state.remaining_pieces(&player, &stone) == 0 {
+                        (self.log)(format!(
+                            "{} has no more remaining {} pieces.",
+                            player, stone
+                        ));
+                        false
+                    } else {
+                        true
+                    }
+                } else {
+                    (self.log)(format!(
+                        "Internal error: lookup for {} failed in is_legal_place.",
+                        pos
+                    ));
+                    false
+                }
+            } else {
+                (self.log)(format!("Position {} is not within bounds.", pos));
+                false
+            }
+        } else {
+            (self.log)(format!(
+                "Internal error: cannot check action with no game state."
+            ));
+            false
+        }
+    }
+
+    fn is_legal_move(
+        &self,
+        player: &Player,
+        pos: &Position,
+        direction: &Direction,
+        drops: &Vec<u8>,
+    ) -> bool {
+        if let Some(state) = self.states.last() {
+            if state.within_bounds(pos) {
+                /* Rules for moving a stack:
+                0. There are stones
+                1. Top stone belongs to player
+                2. Zero or One stones dropped on starting square
+                3. Total number of stones moved does not exceed the carry capacity
+                4. Direction does not contain a capstone
+                5. Wall may only appear on last spot if it's capstone alone that covers
+                6. All stones are used up before then end of the board is met
+                 */
+                if let Some(stack) = &state.board.get(state.pos_to_idx(pos)) {
+                    if stack.len() == 0 {
+                        (self.log)(format!("{} has no stones to move.", pos));
+                        return false;
+                    } else if drops.len() == 0 {
+                        (self.log)(format!("A drop sequence for must be specified for a move."));
+                        return false;
+                    } else if stack[0].player != *player {
+                        (self.log)(format!(
+                            "{} may not move the stack at {} as it belongs to {}.",
+                            player, pos, stack[0].player
+                        ));
+                        return false;
+                    } else if drops[0] > 1 {
+                        (self.log)(format!(
+                            "A move may only drop 0 or 1 stones at it's origin square."
+                        ));
+                        return false;
+                    // Do the sum in u32 just in case ?
+                    } else if drops.iter().map(|&d| d as u32).sum::<u32>() > state.size as u32 {
+                        (self.log)(format!(
+                            "A move may not exceed the carry limit of {} stones.",
+                            state.size
+                        ));
+                        return false;
+                    }
+                    let mut steps: usize = drops.len() - 1;
+                    let cap: bool = stack[0].stone == Stone::Capstone;
+                    let mut pos_new = Position { x: pos.x, y: pos.y };
+
+                    while steps > 0 {
+                        steps -= 1;
+                        if {
+                            match direction {
+                                Direction::Up => pos_new.y + 1 >= state.size,
+                                Direction::Down => pos_new.y == 0,
+                                Direction::Left => pos_new.x + 1 >= state.size,
+                                Direction::Right => pos_new.x == 0,
+                            }
+                        } {
+                            (self.log)(format!("A move may not extend past the board."));
+                            return false;
+                        } else {
+                            match direction {
+                                Direction::Up => pos_new.y += 1,
+                                Direction::Down => pos_new.y -= 1,
+                                Direction::Left => pos_new.x += 1,
+                                Direction::Right => pos_new.x -= 1,
+                            }
+                            if let Some(stack) = &state.board.get(state.pos_to_idx(&pos_new)) {
+                                if stack.len() > 0 {
+                                    match stack[0].stone {
+                                        Stone::Capstone => {
+                                            (self.log)(format!("A move may not cover a capstone."));
+                                            return false;
+                                        }
+                                        Stone::Standing => {
+                                            if (steps > 1) || (!cap) {
+                                                (self.log)(format!(
+                                                    "A move may not cover a standing stone."
+                                                ));
+                                                return false;
+                                            }
+                                        }
+                                        Stone::Flat => (),
+                                    }
+                                }
+                            } else {
+                                (self.log)(format!(
+                                    "Internal error: lookup for {} failed in is_legal_move (1).",
+                                    pos_new
+                                ));
+                                return false;
+                            }
+                        }
+                    }
+                    return true;
+                } else {
+                    (self.log)(format!(
+                        "Internal error: lookup for {} failed in is_legal_move (2).",
+                        pos
+                    ));
+                    return false;
+                }
+            } else {
+                (self.log)(format!("Position {} is not within bounds.", pos));
+                false
+            }
+        } else {
+            (self.log)(format!(
+                "Internal error: cannot check action with no game state."
+            ));
+            false
+        }
+    }
+
+    pub fn is_legal_action(&self, act: &Action) -> bool {
+        match act {
+            Action::Place(player, pos, stone) => self.is_legal_place(player, pos, stone),
+            Action::Move(player, pos, direction, drops) => {
+                self.is_legal_move(player, pos, direction, drops)
+            }
+        }
+    }
+
+    pub fn perform_action(&mut self, act: &Action) -> bool {
+        if self.is_legal_action(act) {
+            let state = &self.states[self.states.len() - 1];
+            let new_state = match act {
+                Action::Place(player, pos, stone) => state.place_stone(*player, pos, *stone),
+                Action::Move(_, pos, direction, drops) => state.move_stack(pos, *direction, drops),
+            };
+            self.states.push(new_state);
+            true
+        } else {
+            false
+        }
+    }
+}
+
+impl<L: Fn(String)> fmt::Display for Game<L> {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(
+            f,
+            "[Date \"\"]\n[Player1 \"{}\"]\n[Player2 \"{}\"]\n[Size \"{}\"]\n{}",
+            self.white_player_name, self.black_player_name, self.size, ptn
+        )
+    }
+}