ref: 6a3f3ec60fcd3588e2ddcec54f75e7a58e6f855d
dir: /chess.c/
#include "moonfish.h"
static char moonfish_delta(struct moonfish *ctx, struct moonfish_move **moves, unsigned char from, unsigned char *to, signed char delta)
{
*to += delta;
if (ctx->board[*to] <= moonfish_our_king) return 0;
(*moves)->from = from;
(*moves)->to = *to;
(*moves)->piece = ctx->board[from];
(*moves)->promotion = ctx->board[from];
(*moves)->captured = ctx->board[*to];
(*moves)->castle = ctx->castle;
(*moves)++;
if (ctx->board[*to] != moonfish_empty) return 0;
return 1;
}
static void moonfish_slide(struct moonfish *ctx, struct moonfish_move **moves, unsigned char from, signed char delta)
{
unsigned char to = from;
while (moonfish_delta(ctx, moves, from, &to, delta)) { }
}
static void moonfish_jump(struct moonfish *ctx, struct moonfish_move **moves, unsigned char from, signed char delta)
{
unsigned char to = from;
moonfish_delta(ctx, moves, from, &to, delta);
}
static void moonfish_move_knight(struct moonfish *ctx, struct moonfish_move **moves, unsigned char from)
{
moonfish_jump(ctx, moves, from, 1 + 20);
moonfish_jump(ctx, moves, from, -1 + 20);
moonfish_jump(ctx, moves, from, 1 - 20);
moonfish_jump(ctx, moves, from, -1 - 20);
moonfish_jump(ctx, moves, from, 2 + 10);
moonfish_jump(ctx, moves, from, -2 + 10);
moonfish_jump(ctx, moves, from, 2 - 10);
moonfish_jump(ctx, moves, from, -2 - 10);
}
static void moonfish_move_bishop(struct moonfish *ctx, struct moonfish_move **moves, unsigned char from)
{
moonfish_slide(ctx, moves, from, 1 + 10);
moonfish_slide(ctx, moves, from, -1 + 10);
moonfish_slide(ctx, moves, from, 1 - 10);
moonfish_slide(ctx, moves, from, -1 - 10);
}
static void moonfish_move_rook(struct moonfish *ctx, struct moonfish_move **moves, unsigned char from)
{
moonfish_slide(ctx, moves, from, 10);
moonfish_slide(ctx, moves, from, -10);
moonfish_slide(ctx, moves, from, 1);
moonfish_slide(ctx, moves, from, -1);
}
static void moonfish_move_queen(struct moonfish *ctx, struct moonfish_move **moves, unsigned char from)
{
moonfish_move_rook(ctx, moves, from);
moonfish_move_bishop(ctx, moves, from);
}
static char moonfish_attacked(struct moonfish *ctx, unsigned char from, unsigned char to)
{
int check;
ctx->board[from] = moonfish_empty;
ctx->board[to] = moonfish_our_king;
check = moonfish_check(ctx);
ctx->board[from] = moonfish_our_king;
ctx->board[to] = moonfish_empty;
return check;
}
static void moonfish_castle_low(struct moonfish *ctx, struct moonfish_move **moves, unsigned char from)
{
int to;
for (to = 22 ; to != from ; to++)
if (ctx->board[to] != moonfish_empty)
return;
if (moonfish_check(ctx)) return;
if (moonfish_attacked(ctx, from, from - 1)) return;
if (moonfish_attacked(ctx, from, from - 2)) return;
(*moves)->from = from;
(*moves)->to = from - 2;
(*moves)->piece = moonfish_our_king;
(*moves)->promotion = moonfish_our_king;
(*moves)->captured = moonfish_empty;
(*moves)->castle = ctx->castle;
(*moves)++;
}
static void moonfish_castle_high(struct moonfish *ctx, struct moonfish_move **moves, unsigned char from)
{
int to;
for (to = 27 ; to != from ; to--)
if (ctx->board[to] != moonfish_empty)
return;
if (moonfish_check(ctx)) return;
if (moonfish_attacked(ctx, from, from + 1)) return;
if (moonfish_attacked(ctx, from, from + 2)) return;
(*moves)->from = from;
(*moves)->to = from + 2;
(*moves)->piece = moonfish_our_king;
(*moves)->promotion = moonfish_our_king;
(*moves)->captured = moonfish_empty;
(*moves)->castle = ctx->castle;
(*moves)++;
}
static void moonfish_move_king(struct moonfish *ctx, struct moonfish_move **moves, unsigned char from)
{
moonfish_jump(ctx, moves, from, 1 + 10);
moonfish_jump(ctx, moves, from, -1 + 10);
moonfish_jump(ctx, moves, from, 1 - 10);
moonfish_jump(ctx, moves, from, -1 - 10);
moonfish_jump(ctx, moves, from, 10);
moonfish_jump(ctx, moves, from, -10);
moonfish_jump(ctx, moves, from, 1);
moonfish_jump(ctx, moves, from, -1);
if (from == 24)
{
if (ctx->castle.black_oo) moonfish_castle_low(ctx, moves, from);
if (ctx->castle.black_ooo) moonfish_castle_high(ctx, moves, from);
}
if (from == 25)
{
if (ctx->castle.white_oo) moonfish_castle_high(ctx, moves, from);
if (ctx->castle.white_ooo) moonfish_castle_low(ctx, moves, from);
}
}
static void moonfish_move_pawn(struct moonfish *ctx, struct moonfish_move **moves, unsigned char from)
{
unsigned char promotion;
promotion = moonfish_our_pawn;
if (from > 80) promotion = moonfish_our_queen;
if (ctx->board[from + 10] == moonfish_empty)
{
(*moves)->piece = moonfish_our_pawn;
(*moves)->promotion = promotion;
(*moves)->captured = moonfish_empty;
(*moves)->from = from;
(*moves)->to = from + 10;
(*moves)->castle = ctx->castle;
(*moves)++;
if (from < 40)
{
if (ctx->board[from + 20] == moonfish_empty)
{
(*moves)->from = from;
(*moves)->to = from + 20;
(*moves)->piece = moonfish_our_pawn;
(*moves)->promotion = moonfish_our_pawn;
(*moves)->captured = moonfish_empty;
(*moves)->castle = ctx->castle;
(*moves)++;
}
}
}
if (ctx->board[from + 9] >= moonfish_their_pawn)
if (ctx->board[from + 9] != moonfish_empty)
{
(*moves)->piece = moonfish_our_pawn;
(*moves)->promotion = promotion;
(*moves)->captured = ctx->board[from + 9];
(*moves)->from = from;
(*moves)->to = from + 9;
(*moves)->castle = ctx->castle;
(*moves)++;
}
if (ctx->board[from + 11] >= moonfish_their_pawn)
if (ctx->board[from + 11] != moonfish_empty)
{
(*moves)->piece = moonfish_our_pawn;
(*moves)->promotion = promotion;
(*moves)->captured = ctx->board[from + 11];
(*moves)->from = from;
(*moves)->to = from + 11;
(*moves)->castle = ctx->castle;
(*moves)++;
}
}
void moonfish_moves(struct moonfish *ctx, struct moonfish_move *moves, unsigned char from)
{
char piece;
piece = ctx->board[from];
if (piece == moonfish_our_pawn) moonfish_move_pawn(ctx, &moves, from);
if (piece == moonfish_our_knight) moonfish_move_knight(ctx, &moves, from);
if (piece == moonfish_our_bishop) moonfish_move_bishop(ctx, &moves, from);
if (piece == moonfish_our_rook) moonfish_move_rook(ctx, &moves, from);
if (piece == moonfish_our_queen) moonfish_move_queen(ctx, &moves, from);
if (piece == moonfish_our_king) moonfish_move_king(ctx, &moves, from);
moves->piece = moonfish_outside;
}
static void moonfish_swap(struct moonfish *ctx, int i, int j)
{
unsigned char piece;
piece = ctx->board[i];
ctx->board[i] = ctx->board[j];
ctx->board[j] = piece;
}
static void moonfish_flip_horizontally(struct moonfish *ctx)
{
int x, y;
for (y = 0 ; y < 8 ; y++)
for (x = 0 ; x < 4 ; x++)
{
moonfish_swap(ctx,
(x + 1) + (y + 2) * 10,
(8 - x) + (y + 2) * 10
);
}
}
static void moonfish_flip_vertically(struct moonfish *ctx)
{
int x, y;
for (y = 0 ; y < 4 ; y++)
for (x = 0 ; x < 8 ; x++)
{
moonfish_swap(ctx,
(x + 1) + (y + 2) * 10,
(x + 1) + (9 - y) * 10
);
}
}
static void moonfish_rotate(struct moonfish *ctx)
{
int x, y;
moonfish_flip_horizontally(ctx);
moonfish_flip_vertically(ctx);
if (ctx->white) ctx->white = 0;
else ctx->white = 1;
for (y = 0 ; y < 8 ; y++)
for (x = 0 ; x < 8 ; x++)
{
if (ctx->board[(x + 1) + (y + 2) * 10] != moonfish_empty)
ctx->board[(x + 1) + (y + 2) * 10] ^= 0x30;
}
}
void moonfish_play(struct moonfish *ctx, struct moonfish_move *move)
{
int x0, x1;
ctx->board[move->from] = moonfish_empty;
ctx->board[move->to] = move->promotion;
if (move->piece == moonfish_our_king)
{
x0 = 0;
if (move->from == 24 && move->to == 22) x0 = 1, x1 = 3, ctx->castle.black_oo = 0;
if (move->from == 24 && move->to == 26) x0 = 8, x1 = 5, ctx->castle.black_ooo = 0;
if (move->from == 25 && move->to == 27) x0 = 8, x1 = 6, ctx->castle.white_oo = 0;
if (move->from == 25 && move->to == 23) x0 = 1, x1 = 4, ctx->castle.white_ooo = 0;
if (x0) ctx->board[x0 + 20] = moonfish_empty, ctx->board[x1 + 20] = moonfish_our_rook;
}
if (move->piece == moonfish_our_rook)
{
if (move->from == 28)
{
if (ctx->white) ctx->castle.white_ooo = 0;
else ctx->castle.black_oo = 0;
}
if (move->from == 21)
{
if (ctx->white) ctx->castle.white_oo = 0;
else ctx->castle.black_ooo = 0;
}
}
moonfish_rotate(ctx);
}
void moonfish_unplay(struct moonfish *ctx, struct moonfish_move *move)
{
int x0, x1;
moonfish_rotate(ctx);
ctx->board[move->from] = move->piece;
ctx->board[move->to] = move->captured;
ctx->castle = move->castle;
if (move->piece == moonfish_our_king)
{
x0 = 0;
if (move->from == 24 && move->to == 22) x0 = 1, x1 = 3;
if (move->from == 24 && move->to == 26) x0 = 8, x1 = 5;
if (move->from == 25 && move->to == 27) x0 = 8, x1 = 6;
if (move->from == 25 && move->to == 23) x0 = 1, x1 = 4;
if (x0) ctx->board[x1 + 20] = moonfish_empty, ctx->board[x0 + 20] = moonfish_our_rook;
}
}
void moonfish_chess(struct moonfish *ctx)
{
static unsigned char pieces[] = {4, 2, 3, 5, 6, 3, 2, 4};
int x, y;
for (y = 0 ; y < 12 ; y++)
for (x = 0 ; x < 10 ; x++)
ctx->board[x + y * 10] = moonfish_outside;
for (x = 0 ; x < 8 ; x++)
{
ctx->board[(x + 1) + 20] = pieces[x] | 0x10;
ctx->board[(x + 1) + 30] = moonfish_our_pawn;
ctx->board[(x + 1) + 40] = moonfish_empty;
ctx->board[(x + 1) + 50] = moonfish_empty;
ctx->board[(x + 1) + 60] = moonfish_empty;
ctx->board[(x + 1) + 70] = moonfish_empty;
ctx->board[(x + 1) + 80] = moonfish_their_pawn;
ctx->board[(x + 1) + 90] = pieces[x] | 0x20;
}
ctx->white = 1;
ctx->castle.white_oo = 1;
ctx->castle.white_ooo = 1;
ctx->castle.black_oo = 1;
ctx->castle.black_ooo = 1;
}
void moonfish_show(struct moonfish *ctx)
{
static char chs[] = "pnbrqk";
int x, y;
char ch;
unsigned char piece;
for (y = 7 ; y >= 0 ; y--)
{
printf(" ");
for (x = 0 ; x < 8 ; x++)
{
piece = ctx->board[(x + 1) + (y + 2) * 10];
if (piece == moonfish_empty)
{
printf(" ");
continue;
}
ch = chs[(piece & 0xF) - 1];
if (piece <= moonfish_our_king || !ctx->white)
if (piece > moonfish_our_king || ctx->white)
ch += 'A' - 'a';
printf("%c ", ch);
}
printf("\n");
}
}
void moonfish_play_uci(struct moonfish *ctx, char *name)
{
struct moonfish_move move;
int x, y;
x = name[0] - 'a';
y = name[1] - '1';
if (!ctx->white)
{
x = 7 - x;
y = 7 - y;
}
move.from = (x + 1) + (y + 2) * 10;
x = name[2] - 'a';
y = name[3] - '1';
if (!ctx->white)
{
x = 7 - x;
y = 7 - y;
}
move.to = (x + 1) + (y + 2) * 10;
move.piece = ctx->board[move.from];
move.captured = ctx->board[move.to];
move.promotion = move.piece;
if (move.piece == moonfish_our_pawn)
if ((move.to - move.from) % 10)
if (move.captured == moonfish_empty)
ctx->board[move.to - 10] = moonfish_empty;
if (name[4] == 'q') move.promotion = moonfish_our_queen;
if (name[4] == 'r') move.promotion = moonfish_our_rook;
if (name[4] == 'b') move.promotion = moonfish_our_bishop;
if (name[4] == 'n') move.promotion = moonfish_our_knight;
moonfish_play(ctx, &move);
}
void moonfish_to_uci(char *name, struct moonfish_move *move, int white)
{
int x, y;
x = move->from % 10 - 1;
y = move->from / 10 - 2;
if (!white)
{
x = 7 - x;
y = 7 - y;
}
name[0] = x + 'a';
name[1] = y + '1';
x = move->to % 10 - 1;
y = move->to / 10 - 2;
if (!white)
{
x = 7 - x;
y = 7 - y;
}
name[2] = x + 'a';
name[3] = y + '1';
if (move->promotion != move->piece)
{
name[4] = 'q';
name[5] = 0;
}
else
{
name[4] = 0;
}
}
void moonfish_fen(struct moonfish *ctx, char *fen)
{
int x, y;
unsigned char type, color;
char ch;
for (y = 0 ; y < 8 ; y++)
for (x = 0 ; x < 8 ; x++)
ctx->board[(x + 1) + (y + 2) * 10] = moonfish_empty;
x = 0;
y = 0;
ctx->white = 1;
ctx->castle.white_oo = 0;
ctx->castle.white_ooo = 0;
ctx->castle.black_oo = 0;
ctx->castle.black_ooo = 0;
for (;;)
{
ch = *fen++;
if (ch == 0) return;
if (ch == ' ') break;
if (ch == '/')
{
x = 0;
y++;
continue;
}
if (ch >= '0' && ch <= '9')
{
x += ch - '0';
continue;
}
if (ch >= 'A' && ch <= 'Z')
ch -= 'A' - 'a',
color = 0x10;
else
color = 0x20;
type = 0;
if (ch == 'p') type = 1;
if (ch == 'n') type = 2;
if (ch == 'b') type = 3;
if (ch == 'r') type = 4;
if (ch == 'q') type = 5;
if (ch == 'k') type = 6;
ctx->board[(x + 1) + (9 - y) * 10] = type | color;
x++;
}
if (*fen++ == 'b') moonfish_rotate(ctx);
if (*fen++ != ' ') return;
for (;;)
{
ch = *fen++;
if (ch == 0) return;
if (ch == ' ') break;
if (ch == 'K') ctx->castle.white_oo = 1;
if (ch == 'Q') ctx->castle.white_ooo = 1;
if (ch == 'k') ctx->castle.black_oo = 1;
if (ch == 'q') ctx->castle.black_ooo = 1;
}
}
int moonfish_validate(struct moonfish *ctx)
{
int x, y;
struct moonfish_move moves[32];
struct moonfish_move *move;
for (y = 0 ; y < 8 ; y++)
for (x = 0 ; x < 8 ; x++)
{
moonfish_moves(ctx, moves, (x + 1) + (y + 2) * 10);
for (move = moves ; move->piece != moonfish_outside ; move++)
if (move->captured == moonfish_their_king)
return 0;
}
return 1;
}
int moonfish_check(struct moonfish *ctx)
{
int valid;
struct moonfish_castle castle;
castle = ctx->castle;
ctx->castle.white_oo = 0;
ctx->castle.white_ooo = 0;
ctx->castle.black_oo = 0;
ctx->castle.black_ooo = 0;
moonfish_rotate(ctx);
valid = moonfish_validate(ctx);
moonfish_rotate(ctx);
ctx->castle = castle;
return valid ? 0 : 1;
}