engine: cleaning

src/board.rs

@@ -69,6 +69,14 @@ pub fn pos(s: &str) -> Pos {
     ((chars[0] - 0x61) as i8, (chars[1] - 0x31) as i8)
 }
 
+/// Return string coordinates from Pos.
+pub fn pos_string(p: &Pos) -> String {
+    let mut bytes = [0u8; 2];
+    bytes[0] = (p.0 + 0x61) as u8;
+    bytes[1] = (p.1 + 0x31) as u8;
+    String::from_utf8_lossy(&bytes).to_string()
+}
+
 /// Bitboard representation of a chess board.
 ///
 /// 64 squares, from A1, A2 to H7, H8. A square is an u8, with bits
@@ -229,6 +237,14 @@ mod tests {
         assert_eq!(pos("h8"), (7, 7));
     }
 
+    #[test]
+    fn test_pos_string() {
+        assert_eq!(pos_string(&(0, 0)), "a1");
+        assert_eq!(pos_string(&(0, 1)), "a2");
+        assert_eq!(pos_string(&(0, 7)), "a8");
+        assert_eq!(pos_string(&(7, 7)), "h8");
+    }
+
     #[test]
     fn test_new_from_fen() {
         let b1 = new();

src/engine.rs

@@ -1,6 +1,8 @@
 //! Vatu engine.
 
 use std::sync::mpsc;
+use std::thread;
+use std::time;
 
 use rand::seq::IteratorRandom;
 
@@ -35,7 +37,7 @@ pub enum Cmd {
     UciGo(Vec<uci::GoArgs>),              // UCI "go" command.
 
     // Commands that can be sent by the engine.
-    BestMove(board::Move),
+    BestMove(Option<board::Move>),
 }
 
 pub const CASTLING_WH_K: u8 = 0b00000001;
@@ -138,15 +140,25 @@ impl Engine {
         self.fullmove = fullmove.parse::<i32>().ok().unwrap();
     }
 
+    fn apply_moves(&mut self, moves: &Vec<board::Move>) {
+        moves.iter().for_each(|m| self.apply_move(m));
+    }
+
+    fn apply_move(&mut self, m: &board::Move) {
+        board::apply_into(&mut self.board, m);
+    }
+
     /// Start working on board, returning the best move found.
     ///
     /// Stop working after `movetime` ms, or go on forever if it's -1.
-    pub fn work(&mut self, _movetime: i32) -> board::Move {
+    pub fn work(&mut self, movetime: i32) -> Option<board::Move> {
         // Stupid engine! Return a random move.
         let moves = rules::get_player_legal_moves(&self.board, self.color);
         let mut rng = rand::thread_rng();
-        let best_move = moves.iter().choose(&mut rng).unwrap();
-        *best_move
+        let best_move = moves.iter().choose(&mut rng).and_then(|m| Some(*m));
+        // board::draw(&self.board);
+        thread::sleep(time::Duration::from_millis(movetime as u64));
+        best_move
     }
 }
 
@@ -180,6 +192,9 @@ impl Engine {
                 uci::PositionArgs::Startpos => {
                     let fen = notation::parse_fen(notation::FEN_START).unwrap();
                     self.apply_fen(&fen);
+                },
+                uci::PositionArgs::Moves(moves) => {
+                    self.apply_moves(&moves);
                 }
             }
         }

src/main.rs

@@ -50,7 +50,7 @@ fn cmd_cli(args: &ArgMatches) -> i32 {
 }
 
 fn cmd_uci(args: &ArgMatches) -> i32 {
-    let output = args.value_of("output");
+    let output = args.value_of("log_file");
     uci::Uci::start(output);
     0
 }

src/notation.rs

@@ -1,5 +1,20 @@
 //! Functions using various notations.
 
+use crate::board;
+
+pub const NULL_MOVE: &str = "0000";
+
+pub fn move_to_string(m: &board::Move) -> String {
+    let mut move_string = String::new();
+    move_string.push_str(&board::pos_string(&m.0));
+    move_string.push_str(&board::pos_string(&m.1));
+    move_string
+}
+
+pub fn parse_move(m_str: &str) -> board::Move {
+    (board::pos(&m_str[0..2]), board::pos(&m_str[2..4]))
+}
+
 pub const FEN_START: &str = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1";
 
 /// FEN notation for positions, split into fields.
@@ -36,6 +51,17 @@ pub fn parse_fen_fields(fields: &[&str]) -> Option<Fen> {
 mod tests {
     use super::*;
 
+    #[test]
+    fn test_move_to_string() {
+        assert_eq!(move_to_string(&((0, 0), (3, 3))), "a1d4");
+        assert_eq!(move_to_string(&((7, 7), (0, 7))), "h8a8");
+    }
+
+    #[test]
+    fn test_parse_move() {
+        assert_eq!(parse_move("a1d4"), ((0, 0), (3, 3)));
+    }
+
     #[test]
     fn test_parse_fen() {
         let fen_start = parse_fen(FEN_START).unwrap();

src/uci.rs

@@ -57,6 +57,7 @@ pub enum UciCmd {
 pub enum PositionArgs {
     Startpos,
     Fen(notation::Fen),
+    Moves(Vec<board::Move>),
 }
 
 /// Arguments for the go remote commands.
@@ -112,11 +113,9 @@ impl Uci {
     }
 
     fn log(&mut self, s: String) {
-        match self.logfile.as_ref()  {
-            Some(mut f) => {
-                f.write_all(s.as_bytes()).unwrap();
-                f.write_all("\n".as_bytes()).unwrap();
-                f.flush().unwrap();
+        match &mut self.logfile {
+            Some(f) => {
+                writeln!(f, "{}", s).unwrap();
             }
             None => {
                 eprintln!("{}", s);
@@ -135,6 +134,7 @@ impl Uci {
     pub fn read_stdin(tx: mpsc::Sender<Cmd>) {
         let mut s = String::new();
         loop {
+            s.clear();
             match io::stdin().read_line(&mut s) {
                 Ok(_) => {
                     let s = s.trim();
@@ -147,7 +147,6 @@ impl Uci {
                     eprintln!("Failed to read input: {:?}", e);
                 }
             }
-            s.clear();
         }
     }
 
@@ -217,8 +216,12 @@ impl Uci {
     }
 
     /// Send best move.
-    fn send_bestmove(&mut self, m: &board::Move) {
-        self.send(&format!("bestmove {:?}", m));  // TODO notation conversion
+    fn send_bestmove(&mut self, m: &Option<board::Move>) {
+        let move_str = match m {
+            Some(m) => notation::move_to_string(m),
+            None => notation::NULL_MOVE.to_string(),
+        };
+        self.send(&format!("bestmove {}", move_str));
     }
 }
 
@@ -245,20 +248,34 @@ fn parse_command(s: &str) -> UciCmd {
 
 /// Parse an UCI "position" command.
 fn parse_position_command(fields: &[&str]) -> UciCmd {
-    // Currently we only match the first subcommand; moves are not supported.
+    let num_fields = fields.len();
+    let mut i = 0;
     let mut subcommands = vec!();
-    match fields[0] {
-        // Subcommand "fen" is followed by a FEN string.
-        "fen" => {
-            if let Some(fen) = notation::parse_fen_fields(&fields[1..7]) {
-                subcommands.push(PositionArgs::Fen(fen))
-            } else {
-                return UciCmd::Unknown(format!("Bad format for position fen"))
+    while i < num_fields {
+        match fields[i] {
+            // Subcommand "fen" is followed by a FEN string.
+            "fen" => {
+                if let Some(fen) = notation::parse_fen_fields(&fields[i + 1 .. i + 7]) {
+                    subcommands.push(PositionArgs::Fen(fen))
+                } else {
+                    return UciCmd::Unknown(format!("Bad format for position fen"))
+                }
+                i += 6;
             }
+            // Subcommand "startpos" assumes the board is a new game.
+            "startpos" => subcommands.push(PositionArgs::Startpos),
+            // Subcommand "moves" is followed by moves until the end of the command.
+            "moves" => {
+                let mut moves = vec!();
+                while i + 1 < num_fields {
+                    moves.push(notation::parse_move(fields[i + 1]));
+                    i += 1;
+                }
+                subcommands.push(PositionArgs::Moves(moves));
+            },
+            f => return UciCmd::Unknown(format!("Unknown position subcommand: {}", f)),
         }
-        // Subcommand "startpos" assumes the board is a new game.
-        "startpos" => subcommands.push(PositionArgs::Startpos),
-        f => return UciCmd::Unknown(format!("Unknown position subcommand: {}", f)),
+        i += 1;
     }
     UciCmd::Position(subcommands)
 }