terminal-chess: src/game.c@970748b9a73b (annotated)

src/game.c@970748b9a73b (annotated)

src/game.c

Wed, 26 Mar 2014 14:53:15 +0100

author: Mike Becker <universe@uap-core.de>
date: Wed, 26 Mar 2014 14:53:15 +0100
changeset 14: 970748b9a73b
parent 13: faec61c4901f
child 15: 7ffd66591afe
permissions: -rw-r--r--

fixed crucial bug where both players could move at the same time + added pawn rules (TODO: en passant)

 /*
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
  *
  * Copyright 2014 Mike Becker. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *
  *   1. Redistributions of source code must retain the above copyright
  *      notice, this list of conditions and the following disclaimer.
  *
  *   2. Redistributions in binary form must reproduce the above copyright
  *      notice, this list of conditions and the following disclaimer in the
  *      documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  * POSSIBILITY OF SUCH DAMAGE.
  *
  */
 #include "game.h"
 #include "input.h"
 #include "rules/rules.h"
 #include <ncurses.h>
 #include <string.h>
 static const uint8_t boardx = 10, boardy = 10;
 static void draw_board(Board board, uint8_t mycolor) {
     for (uint8_t y = 0 ; y < 8 ; y++) {
         for (uint8_t x = 0 ; x < 8 ; x++) {
             uint8_t col = board[y][x] & COLOR_MASK;
             uint8_t piece = board[y][x] & PIECE_MASK;
             char piecec = ' ';
             switch (piece) {
                 case PAWN: piecec = 'P'; break;
                 case ROOK: piecec = 'R'; break;
                 case KNIGHT: piecec = 'N'; break;
                 case BISHOP: piecec = 'B'; break;
                 case QUEEN: piecec = 'Q'; break;
                 case KING: piecec = 'K'; break;
             }
             attrset((col == WHITE ? A_BOLD : A_DIM) |
                 COLOR_PAIR((y&1)==(x&1) ? COL_WB : COL_BW));
             int cy = mycolor == WHITE ? boardy-y : boardy-7+y;
             int cx = mycolor == WHITE ? boardx+x*3 : boardx+21-x*3;
             mvaddch(cy, cx, ' ');
             mvaddch(cy, cx+1, piecec);
             mvaddch(cy, cx+2, ' ');
         }
     }
     attrset(A_NORMAL);
     for (uint8_t i = 0 ; i < 8 ; i++) {
         int x = mycolor == WHITE ? boardx+i*3+1 : boardx+22-i*3;
         int y = mycolor == WHITE ? boardy-i : boardy-7+i;
         mvaddch(boardy+1, x, 'a'+i);
         mvaddch(y, boardx-2, '1'+i);
     }
 }
 /**
  * Applies a move and deletes captured pieces.
  *
  * @param board the current board state
  * @param move the move to apply
  */
 static void apply_move(Board board, Move *move) {
     msrc(board, move) = 0;
     // TODO: care for en passant capture
     mdst(board, move) = move->piece;
     /* castling */
     if ((move->piece & PIECE_MASK) == KING &&
         move->fromfile == fileidx('e')) {
         uint8_t color = move->piece & COLOR_MASK;
         if (move->tofile == fileidx('g')) {
             board[move->torow][fileidx('h')] = 0;
             board[move->torow][fileidx('f')] = color|ROOK;
         } else if (move->tofile == fileidx('c')) {
             board[move->torow][fileidx('a')] = 0;
             board[move->torow][fileidx('d')] = color|ROOK;
         }
     }
 }
 /**
  * Validates move by applying chess rules.
  * @param board the current board state
  * @param move the move to validate
  * @return TRUE, if the move complies to chess rules, FALSE otherwise
  */
 static _Bool validate_move(Board board, Move *move) {
     _Bool result;
     /* validate indices (don't trust opponent) */
     if (!chkidx(move)) {
         return FALSE;
     }
     /* does piece exist */
     result = msrc(board, move) == move->piece;
     /* can't capture own pieces */
     if ((mdst(board, move) & COLOR_MASK) == (move->piece & COLOR_MASK)) {
         return FALSE;
     }
     /* validate individual rules */
     switch (move->piece & PIECE_MASK) {
     case PAWN:
         result = result && pawn_chkrules(board, move);
         result = result && !pawn_isblocked(board, move);
         break;
     case ROOK:
         result = result && rook_chkrules(board, move);
         result = result && !rook_isblocked(board, move);
         break;
     case KNIGHT:
         result = result && knight_chkrules(board, move);
         result = result && !knight_isblocked(board, move);
         break;
     case BISHOP:
         result = result && bishop_chkrules(board, move);
         result = result && !bishop_isblocked(board, move);
         break;
     case QUEEN:
         result = result && queen_chkrules(board, move);
         result = result && !queen_isblocked(board, move);
         break;
     case KING:
         result = result && king_chkrules(board, move);
         result = result && !king_isblocked(board, move);
         break;
     default:
         result = FALSE;
     }
     /* is piece pinned */
     // TODO: make it so
     /* correct check and checkmate flags */
     // TODO: make it so
     return result;
 }
 /**
  * Maps a character to a piece.
  *
  * Does not work for pawns, since they don't have a character.
  *
  * @param c one of R,N,B,Q,K
  * @return numeric value for the specified piece
  */
 static uint8_t getpiece(char c) {
     switch (c) {
         case 'R': return ROOK;
         case 'N': return KNIGHT;
         case 'B': return BISHOP;
         case 'Q': return QUEEN;
         case 'K': return KING;
         default: return 0;
     }
 }
 /**
  * Guesses the location of a piece for short algebraic notation.
  *
  * @param board the current state of the board
  * @param move the move date to operate on
  * @return TRUE if the location could be retrieved, FALSE if the location is
  * ambiguous
  */
 static _Bool getlocation(Board board, Move *move) {
     uint8_t piece = move->piece & PIECE_MASK;
     switch (piece) {
         case PAWN: return pawn_getlocation(board, move);
         case ROOK: return rook_getlocation(board, move);
         case KNIGHT: return knight_getlocation(board, move);
         case BISHOP: return bishop_getlocation(board, move);
         case QUEEN: return queen_getlocation(board, move);
         case KING: return king_getlocation(board, move);
         default: return FALSE;
     }
 }
 /**
  * Evaluates a move syntactically and stores the move data in the specified
  * object.
  *
  * @param board the current state of the board
  * @param mycolor the color of the current player
  * @param mstr the input string to parse
  * @param move a pointer to object where the move data shall be stored
  * @return TRUE, if the move is syntactically valid, FALSE otherwise
  */
 static _Bool eval_move(Board board, uint8_t mycolor, char *mstr, Move *move) {
     memset(move, 0, sizeof(Move));
     move->fromfile = POS_UNSPECIFIED;
     move->fromrow = POS_UNSPECIFIED;
     size_t len = strlen(mstr);
     /* evaluate check/checkmate flags */
     if (mstr[len-1] == '+') {
         len--; mstr[len] = '\0';
         move->check = TRUE;
     } else if (mstr[len-1] == '#') {
         len--; mstr[len] = '\0';
         move->checkmate = TRUE;
     }
     if (len == 2) {
         /* pawn move (e.g. "e4") */
         move->piece = PAWN;
         move->tofile = fileidx(mstr[0]);
         move->torow = rowidx(mstr[1]);
     } else if (len == 3) {
         if (strcmp(mstr, "O-O") == 0) {
             /* king side castling */
             move->piece = KING;
             move->fromfile = fileidx('e');
             move->tofile = fileidx('g');
             move->fromrow = move->torow = mycolor == WHITE ? 0 : 7;
         } else {
             /* move (e.g. "Nf3") */
             move->piece = getpiece(mstr[0]);
             move->tofile = fileidx(mstr[1]);
             move->torow = rowidx(mstr[2]);
         }
     } else if (len == 4) {
         move->piece = getpiece(mstr[0]);
         if (mstr[1] == 'x') {
             /* capture (e.g. "Nxf3", "dxe5") */
             move->capture = TRUE;
             if (!move->piece) {
                 move->piece = PAWN;
                 move->fromfile = fileidx(mstr[0]);
             }
         } else {
             /* move (e.g. "Ndf3", "N2c3") */
             move->fromfile = isfile(mstr[1]) ?
                 fileidx(mstr[1]) : rowidx(mstr[1]);
         }
         move->tofile = fileidx(mstr[2]);
         move->torow = rowidx(mstr[3]);
     } else if (len == 5) {
         if (strcmp(mstr, "O-O-O") == 0) {
             /* queen side castling "O-O-O" */
             move->piece = KING;
             move->fromfile = fileidx('e');
             move->tofile = fileidx('c');
             move->fromrow = move->torow = mycolor == WHITE ? 0 : 7;
         } else {
             move->piece = getpiece(mstr[0]);
             if (mstr[2] == 'x') {
                 move->capture = TRUE;
                 if (move->piece) {
                     /* capture (e.g. "Ndxf3") */
                     move->fromfile = fileidx(mstr[1]);
                 } else {
                     /* long notation capture (e.g. "e5xf6") */
                     move->piece = PAWN;
                     move->fromfile = fileidx(mstr[0]);
                     move->fromrow = rowidx(mstr[1]);
                 }
             } else {
                 /* long notation move (e.g. "Nc5a4") */
                 move->fromfile = fileidx(mstr[1]);
                 move->fromrow = rowidx(mstr[2]);
             }
             move->tofile = fileidx(mstr[3]);
             move->torow = rowidx(mstr[4]);
         }
     } else if (len == 6) {
         /* long notation capture (e.g. "Nc5xf3") */
         if (mstr[3] == 'x') {
             move->capture = TRUE;
             move->piece = getpiece(mstr[0]);
             move->fromfile = fileidx(mstr[1]);
             move->fromrow = rowidx(mstr[2]);
             move->tofile = fileidx(mstr[4]);
             move->torow = rowidx(mstr[5]);
         }
     }
     if (move->piece) {
         move->piece |= mycolor;
         if (move->fromfile == POS_UNSPECIFIED
             || move->fromrow == POS_UNSPECIFIED) {
             return getlocation(board, move) && chkidx(move);
         } else {
             return chkidx(move);
         }
     } else {
         return FALSE;
     }
     // TODO: return status code to indicate the error type
 }
 static int sendmove(Board board, uint8_t mycolor, int opponent) {
     const size_t buflen = 8;
     char movestr[buflen];
     _Bool remisrejected = FALSE;
     uint8_t code;
     while (1) {
         move(boardy+3, 0);
         if (remisrejected) {
             printw(
                 "Use chess notation to enter your move.\n"
                 "Remis offer rejected - type 'surr' to surrender.      \n\n"
                 "Type your move: ");
         } else {
             printw(
                 "Use chess notation to enter your move.\n"
                 "Or type 'surr' to surrender or 'remis' to offer remis.\n\n"
                 "Type your move: ");
         }
         clrtoeol();
         refresh();
         getnstr(movestr, buflen);
         if (strncmp(movestr, "surr", buflen) == 0) {
             printw("You surrendered!");
             refresh();
             net_send_code(opponent, NETCODE_SURRENDER);
             return 1;
         } else if (strncmp(movestr, "remis", buflen) == 0) {
             if (!remisrejected) {
                 net_send_code(opponent, NETCODE_REMIS);
                 printw("Remis offer sent - waiting for acceptance...");
                 refresh();
                 if (net_recieve_code(opponent) == NETCODE_ACCEPT) {
                     printw("\rRemis accepted!");
                     clrtoeol();
                     refresh();
                     return 1;
                 } else {
                     remisrejected = TRUE;
                 }
             }
         } else {
             Move move;
             if (eval_move(board, mycolor, movestr, &move)) {
                 net_send_code(opponent, NETCODE_MOVE);
                 net_send_data(opponent, &move, sizeof(Move));
                 code = net_recieve_code(opponent);
                 move.check = code == NETCODE_CHECK;
                 move.checkmate = code == NETCODE_CHECKMATE;
                 // TODO: record move
                 if (code == NETCODE_DECLINE) {
                     printw("Invalid move.");
                     clrtoeol();
                 } else {
                     apply_move(board, &move);
                     if (move.checkmate) {
                         printw("Checkmate!");
                         return 1;
                     } else {
                         return 0;
                     }
                 }
             } else {
                 printw("Can't interpret move - please use algebraic notation.");
             }
         }
     }
 }
 static int recvmove(Board board, int opponent) {
     while (1) {
         move(boardy+3, 0);
         printw("Awaiting opponent move...");
         clrtoeol();
         refresh();
         // TODO: nonblocking
         uint32_t code = net_recieve_code(opponent);
         Move move;
         switch (code) {
             case NETCODE_SURRENDER:
                 printw("\rYour opponent surrendered!");
                 clrtoeol();
                 return 1;
             case NETCODE_REMIS:
                 if (prompt_yesno(
                     "\rYour opponent offers remis - do you accept")) {
                     printw("\rRemis accepted!");
                     clrtoeol();
                     net_send_code(opponent, NETCODE_ACCEPT);
                     return 1;
                 } else {
                     net_send_code(opponent, NETCODE_DECLINE);
                 }
                 break;
             case NETCODE_MOVE:
                 net_recieve_data(opponent, &move, sizeof(Move));
                 if (validate_move(board, &move)) {
                     apply_move(board, &move);
                     // TODO: record move
                     if (move.check) {
                         net_send_code(opponent, NETCODE_CHECK);
                     } else if (move.checkmate) {
                         net_send_code(opponent, NETCODE_CHECKMATE);
                     } else {
                         net_send_code(opponent, NETCODE_ACCEPT);
                     }
                     return 0;
                 } else {
                     net_send_code(opponent, NETCODE_DECLINE);
                 }
         }
     }
 }
 void game_start(Settings *settings, int opponent) {
     _Bool myturn = is_server(settings) ==
         (settings->gameinfo.servercolor == WHITE);
     uint8_t mycolor = myturn ? WHITE:BLACK;
     _Bool running;
     Board board = {
         {WROOK, WKNIGHT, WBISHOP, WQUEEN, WKING, WBISHOP, WKNIGHT, WROOK},
         {WPAWN, WPAWN,   WPAWN,   WPAWN,  WPAWN, WPAWN,   WPAWN,   WPAWN},
         {0,     0,       0,       0,      0,     0,       0,       0},
         {0,     0,       0,       0,      0,     0,       0,       0},
         {0,     0,       0,       0,      0,     0,       0,       0},
         {0,     0,       0,       0,      0,     0,       0,       0},
         {BPAWN, BPAWN,   BPAWN,   BPAWN,  BPAWN, BPAWN,   BPAWN,   BPAWN},
         {BROOK, BKNIGHT, BBISHOP, BQUEEN, BKING, BBISHOP, BKNIGHT, BROOK}
     };
     do {
         clear();
         draw_board(board, mycolor);
         if (myturn) {
             running = !sendmove(board, mycolor, opponent);
         } else {
             running = !recvmove(board, opponent);
             flushinp(); // flush any input the user hacked in while waiting
         }
         myturn ^= TRUE;
     }  while (running);
     mvaddstr(getmaxy(tchess_window)-1, 0,
         "Game has ended. Press any key to leave...");
     getch();
 }

Mercurial > hg > terminal-chess / annotate

src/game.c@970748b9a73b (annotated)

src/game.c