X-Git-Url: https://git.auder.net/?a=blobdiff_plain;f=client%2Fsrc%2Fvariants%2FCheckered2.js;fp=client%2Fsrc%2Fvariants%2FCheckered2.js;h=db288766e2085fa4d0e764ecddee58cff3b68caf;hb=af34341d92d47d14f396e7f4adb81f2a7e9d9a61;hp=0000000000000000000000000000000000000000;hpb=fef153df51fe60a5af4c5b2a05e0b1177187bf62;p=vchess.git

diff --git a/client/src/variants/Checkered2.js b/client/src/variants/Checkered2.js
new file mode 100644
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--- /dev/null
+++ b/client/src/variants/Checkered2.js
@@ -0,0 +1,465 @@
+import { ChessRules, Move, PiPo } from "@/base_rules";
+
+export class Checkered2Rules extends ChessRules {
+  static board2fen(b) {
+    const checkered_codes = {
+      p: "s",
+      q: "t",
+      r: "u",
+      b: "c",
+      n: "o"
+    };
+    if (b[0] == "c") return checkered_codes[b[1]];
+    return ChessRules.board2fen(b);
+  }
+
+  static fen2board(f) {
+    // Tolerate upper-case versions of checkered pieces (why not?)
+    const checkered_pieces = {
+      s: "p",
+      S: "p",
+      t: "q",
+      T: "q",
+      u: "r",
+      U: "r",
+      c: "b",
+      C: "b",
+      o: "n",
+      O: "n"
+    };
+    if (Object.keys(checkered_pieces).includes(f))
+      return "c" + checkered_pieces[f];
+    return ChessRules.fen2board(f);
+  }
+
+  static get PIECES() {
+    return ChessRules.PIECES.concat(["s", "t", "u", "c", "o"]);
+  }
+
+  getPpath(b) {
+    return (b[0] == "c" ? "Checkered/" : "") + b;
+  }
+
+  setOtherVariables(fen) {
+    super.setOtherVariables(fen);
+    // Local stack of non-capturing checkered moves:
+    this.cmoves = [];
+    const cmove = V.ParseFen(fen).cmove;
+    if (cmove == "-") this.cmoves.push(null);
+    else {
+      this.cmoves.push({
+        start: ChessRules.SquareToCoords(cmove.substr(0, 2)),
+        end: ChessRules.SquareToCoords(cmove.substr(2))
+      });
+    }
+  }
+
+  static IsGoodFen(fen) {
+    if (!ChessRules.IsGoodFen(fen)) return false;
+    const fenParts = fen.split(" ");
+    if (fenParts.length != 6) return false;
+    if (fenParts[5] != "-" && !fenParts[5].match(/^([a-h][1-8]){2}$/))
+      return false;
+    return true;
+  }
+
+  static IsGoodFlags(flags) {
+    // 4 for castle + 16 for pawns
+    return !!flags.match(/^[a-z]{4,4}[01]{16,16}$/);
+  }
+
+  setFlags(fenflags) {
+    super.setFlags(fenflags); //castleFlags
+    this.pawnFlags = {
+      w: [...Array(8)], //pawns can move 2 squares?
+      b: [...Array(8)]
+    };
+    const flags = fenflags.substr(4); //skip first 4 letters, for castle
+    for (let c of ["w", "b"]) {
+      for (let i = 0; i < 8; i++)
+        this.pawnFlags[c][i] = flags.charAt((c == "w" ? 0 : 8) + i) == "1";
+    }
+  }
+
+  aggregateFlags() {
+    return [this.castleFlags, this.pawnFlags];
+  }
+
+  disaggregateFlags(flags) {
+    this.castleFlags = flags[0];
+    this.pawnFlags = flags[1];
+  }
+
+  getEpSquare(moveOrSquare) {
+    if (typeof moveOrSquare !== "object" || moveOrSquare.appear[0].c != 'c')
+      return super.getEpSquare(moveOrSquare);
+    // Checkered move: no en-passant
+    return undefined;
+  }
+
+  getCmove(move) {
+    if (move.appear[0].c == "c" && move.vanish.length == 1)
+      return { start: move.start, end: move.end };
+    return null;
+  }
+
+  canTake([x1, y1], [x2, y2]) {
+    const color1 = this.getColor(x1, y1);
+    const color2 = this.getColor(x2, y2);
+    // Checkered aren't captured
+    return (
+      color1 != color2 &&
+      color2 != "c" &&
+      (color1 != "c" || color2 != this.turn)
+    );
+  }
+
+  // Post-processing: apply "checkerization" of standard moves
+  getPotentialMovesFrom([x, y]) {
+    let standardMoves = super.getPotentialMovesFrom([x, y]);
+    const lastRank = this.turn == "w" ? 0 : 7;
+    // King is treated differently: it never turn checkered
+    if (this.getPiece(x, y) == V.KING) return standardMoves;
+    let moves = [];
+    standardMoves.forEach(m => {
+      if (m.vanish[0].p == V.PAWN) {
+        if (
+          Math.abs(m.end.x - m.start.x) == 2 &&
+          !this.pawnFlags[this.turn][m.start.y]
+        ) {
+          return; //skip forbidden 2-squares jumps
+        }
+        if (
+          this.board[m.end.x][m.end.y] == V.EMPTY &&
+          m.vanish.length == 2 &&
+          this.getColor(m.start.x, m.start.y) == "c"
+        ) {
+          return; //checkered pawns cannot take en-passant
+        }
+      }
+      if (m.vanish.length == 1)
+        // No capture
+        moves.push(m);
+      else {
+        // A capture occured (m.vanish.length == 2)
+        m.appear[0].c = "c";
+        moves.push(m);
+        if (
+          // Avoid promotions (already treated):
+          m.appear[0].p != m.vanish[1].p &&
+          (m.vanish[0].p != V.PAWN || m.end.x != lastRank)
+        ) {
+          // Add transformation into captured piece
+          let m2 = JSON.parse(JSON.stringify(m));
+          m2.appear[0].p = m.vanish[1].p;
+          moves.push(m2);
+        }
+      }
+    });
+    return moves;
+  }
+
+  getPotentialPawnMoves([x, y]) {
+    let moves = super.getPotentialPawnMoves([x, y]);
+    // Post-process: set right color for checkered moves
+    if (this.getColor(x, y) == 'c') {
+      moves.forEach(m => {
+        m.appear[0].c = 'c'; //may be done twice if capture
+        m.vanish[0].c = 'c';
+      });
+    }
+    return moves;
+  }
+
+  canIplay(side, [x, y]) {
+    return side == this.turn && [side, "c"].includes(this.getColor(x, y));
+  }
+
+  // Does m2 un-do m1 ? (to disallow undoing checkered moves)
+  oppositeMoves(m1, m2) {
+    return (
+      !!m1 &&
+      m2.appear[0].c == "c" &&
+      m2.appear.length == 1 &&
+      m2.vanish.length == 1 &&
+      m1.start.x == m2.end.x &&
+      m1.end.x == m2.start.x &&
+      m1.start.y == m2.end.y &&
+      m1.end.y == m2.start.y
+    );
+  }
+
+  filterValid(moves) {
+    if (moves.length == 0) return [];
+    const color = this.turn;
+    const L = this.cmoves.length; //at least 1: init from FEN
+    return moves.filter(m => {
+      if (this.oppositeMoves(this.cmoves[L - 1], m)) return false;
+      this.play(m);
+      const res = !this.underCheck(color);
+      this.undo(m);
+      return res;
+    });
+  }
+
+  getAllValidMoves() {
+    const oppCol = V.GetOppCol(this.turn);
+    let potentialMoves = [];
+    for (let i = 0; i < V.size.x; i++) {
+      for (let j = 0; j < V.size.y; j++) {
+        // NOTE: just testing == color isn't enough because of checkered pieces
+        if (this.board[i][j] != V.EMPTY && this.getColor(i, j) != oppCol) {
+          Array.prototype.push.apply(
+            potentialMoves,
+            this.getPotentialMovesFrom([i, j])
+          );
+        }
+      }
+    }
+    return this.filterValid(potentialMoves);
+  }
+
+  atLeastOneMove() {
+    const oppCol = V.GetOppCol(this.turn);
+    for (let i = 0; i < V.size.x; i++) {
+      for (let j = 0; j < V.size.y; j++) {
+        // NOTE: just testing == color isn't enough because of checkered pieces
+        if (this.board[i][j] != V.EMPTY && this.getColor(i, j) != oppCol) {
+          const moves = this.getPotentialMovesFrom([i, j]);
+          if (moves.length > 0) {
+            for (let k = 0; k < moves.length; k++) {
+              if (this.filterValid([moves[k]]).length > 0) return true;
+            }
+          }
+        }
+      }
+    }
+    return false;
+  }
+
+  // colors: array, generally 'w' and 'c' or 'b' and 'c'
+  isAttacked(sq, colors) {
+    if (!Array.isArray(colors)) colors = [colors];
+    return (
+      this.isAttackedByPawn(sq, colors) ||
+      this.isAttackedByRook(sq, colors) ||
+      this.isAttackedByKnight(sq, colors) ||
+      this.isAttackedByBishop(sq, colors) ||
+      this.isAttackedByQueen(sq, colors) ||
+      this.isAttackedByKing(sq, colors)
+    );
+  }
+
+  isAttackedByPawn([x, y], colors) {
+    for (let c of colors) {
+      const color = (c == "c" ? this.turn : c);
+      let pawnShift = color == "w" ? 1 : -1;
+      if (x + pawnShift >= 0 && x + pawnShift < 8) {
+        for (let i of [-1, 1]) {
+          if (
+            y + i >= 0 &&
+            y + i < 8 &&
+            this.getPiece(x + pawnShift, y + i) == V.PAWN &&
+            this.getColor(x + pawnShift, y + i) == c
+          ) {
+            return true;
+          }
+        }
+      }
+    }
+    return false;
+  }
+
+  isAttackedBySlideNJump([x, y], colors, piece, steps, oneStep) {
+    for (let step of steps) {
+      let rx = x + step[0],
+          ry = y + step[1];
+      while (V.OnBoard(rx, ry) && this.board[rx][ry] == V.EMPTY && !oneStep) {
+        rx += step[0];
+        ry += step[1];
+      }
+      if (
+        V.OnBoard(rx, ry) &&
+        this.getPiece(rx, ry) === piece &&
+        colors.includes(this.getColor(rx, ry))
+      ) {
+        return true;
+      }
+    }
+    return false;
+  }
+
+  isAttackedByRook(sq, colors) {
+    return this.isAttackedBySlideNJump(sq, colors, V.ROOK, V.steps[V.ROOK]);
+  }
+
+  isAttackedByKnight(sq, colors) {
+    return this.isAttackedBySlideNJump(
+      sq,
+      colors,
+      V.KNIGHT,
+      V.steps[V.KNIGHT],
+      "oneStep"
+    );
+  }
+
+  isAttackedByBishop(sq, colors) {
+    return this.isAttackedBySlideNJump(
+      sq, colors, V.BISHOP, V.steps[V.BISHOP]);
+  }
+
+  isAttackedByQueen(sq, colors) {
+    return this.isAttackedBySlideNJump(
+      sq,
+      colors,
+      V.QUEEN,
+      V.steps[V.ROOK].concat(V.steps[V.BISHOP])
+    );
+  }
+
+  isAttackedByKing(sq, colors) {
+    return this.isAttackedBySlideNJump(
+      sq,
+      colors,
+      V.KING,
+      V.steps[V.ROOK].concat(V.steps[V.BISHOP]),
+      "oneStep"
+    );
+  }
+
+  underCheck(color) {
+    return this.isAttacked(this.kingPos[color], [V.GetOppCol(color), "c"]);
+  }
+
+  getCheckSquares() {
+    const color = this.turn;
+    // Artifically change turn, for checkered pawns
+    this.turn = V.GetOppCol(color);
+    const kingAttacked =
+      this.isAttacked(
+        this.kingPos[color],
+        [this.turn, 'c']
+      );
+    let res = kingAttacked
+      ? [JSON.parse(JSON.stringify(this.kingPos[color]))]
+      : [];
+    this.turn = color;
+    return res;
+  }
+
+  postPlay(move) {
+    super.postPlay(move);
+    // Does this move turn off a 2-squares pawn flag?
+    if ([1, 6].includes(move.start.x) && move.vanish[0].p == V.PAWN)
+      this.pawnFlags[move.start.x == 6 ? "w" : "b"][move.start.y] = false;
+    this.cmoves.push(this.getCmove(move));
+  }
+
+  postUndo(move) {
+    super.postUndo(move);
+    this.cmoves.pop();
+  }
+
+  getCurrentScore() {
+    if (this.atLeastOneMove()) return "*";
+    const color = this.turn;
+    // Artifically change turn, for checkered pawns
+    this.turn = V.GetOppCol(this.turn);
+    const res = this.isAttacked(this.kingPos[color], [V.GetOppCol(color), "c"])
+      ? color == "w"
+        ? "0-1"
+        : "1-0"
+      : "1/2";
+    this.turn = V.GetOppCol(this.turn);
+    return res;
+  }
+
+  evalPosition() {
+    let evaluation = 0;
+    // Just count material for now, considering checkered neutral (...)
+    for (let i = 0; i < V.size.x; i++) {
+      for (let j = 0; j < V.size.y; j++) {
+        if (this.board[i][j] != V.EMPTY) {
+          const sqColor = this.getColor(i, j);
+          if (["w","b"].includes(sqColor)) {
+            const sign = sqColor == "w" ? 1 : -1;
+            evaluation += sign * V.VALUES[this.getPiece(i, j)];
+          }
+        }
+      }
+    }
+    return evaluation;
+  }
+
+  static GenRandInitFen(randomness) {
+    // Add 16 pawns flags + empty cmove:
+    return ChessRules.GenRandInitFen(randomness)
+      .slice(0, -2) + "1111111111111111 - -";
+  }
+
+  static ParseFen(fen) {
+    return Object.assign(
+      ChessRules.ParseFen(fen),
+      { cmove: fen.split(" ")[5] }
+    );
+  }
+
+  getCmoveFen() {
+    const L = this.cmoves.length;
+    return (
+      !this.cmoves[L - 1]
+        ? "-"
+        : ChessRules.CoordsToSquare(this.cmoves[L - 1].start) +
+          ChessRules.CoordsToSquare(this.cmoves[L - 1].end)
+    );
+  }
+
+  getFen() {
+    return super.getFen() + " " + this.getCmoveFen();
+  }
+
+  getFenForRepeat() {
+    return super.getFenForRepeat() + "_" + this.getCmoveFen();
+  }
+
+  getFlagsFen() {
+    let fen = super.getFlagsFen();
+    // Add pawns flags
+    for (let c of ["w", "b"])
+      for (let i = 0; i < 8; i++) fen += (this.pawnFlags[c][i] ? "1" : "0");
+    return fen;
+  }
+
+  static get SEARCH_DEPTH() {
+    return 2;
+  }
+
+  getNotation(move) {
+    if (move.appear.length == 2) {
+      // Castle
+      if (move.end.y < move.start.y) return "0-0-0";
+      return "0-0";
+    }
+
+    const finalSquare = V.CoordsToSquare(move.end);
+    const piece = this.getPiece(move.start.x, move.start.y);
+    let notation = "";
+    if (piece == V.PAWN) {
+      // Pawn move
+      if (move.vanish.length > 1) {
+        // Capture
+        const startColumn = V.CoordToColumn(move.start.y);
+        notation = startColumn + "x" + finalSquare;
+      } else notation = finalSquare;
+    } else {
+      // Piece movement
+      notation =
+        piece.toUpperCase() +
+        (move.vanish.length > 1 ? "x" : "") +
+        finalSquare;
+    }
+    if (move.appear[0].p != move.vanish[0].p)
+      notation += "=" + move.appear[0].p.toUpperCase();
+    return notation;
+  }
+};