import { _decorator } from "cc";

const { ccclass } = _decorator;

@ccclass("ChessPos")
export default class ChessPos {
  clearBoard = function() {
    this.sdPlayer = 0;
    this.squares = []; //这就是一维棋局数组。
    for (var sq = 0; sq < 256; sq ++) {
      this.squares.push(0);
    }
    this.zobristKey = this.zobristLock = 0;
    this.vlWhite = this.vlBlack = 0;
  };

  mvList:any[] = []
  pcList:any[] = []
  keyList:any[] = []
  chkList:any[] = []
  squares:any[] = []
  distance:number = 0
  vlWhite:number = 0
  vlBlack:number = 0
  zobristKey:number = 0
  zobristLock:number = 0
  sdPlayer:number = 0
  setIrrev() {
    this.mvList = [0];
    this.pcList = [0];
    this.keyList = [0];
    this.chkList = [this.checked()];
    this.distance = 0;
  }

// 如果bDel为false，则将棋子pc添加进棋局中的sp位置；如果bDel为true，则删除sp位置的棋子。
  private addPiece(sq, pc, bDel) {
    var pcAdjust;
    this.squares[sq] = bDel ? 0 : pc;
    if(pc<8){
      console.log("addPiece error",pc)
    }
    if (pc < 16) {
      pcAdjust = pc - 8;
      this.vlWhite += bDel ? -PIECE_VALUE[pcAdjust][sq] :
          PIECE_VALUE[pcAdjust][sq];
  
    } else {
      pcAdjust = pc - 16;
      this.vlBlack += bDel ? -PIECE_VALUE[pcAdjust][SQUARE_FLIP(sq)] :
          PIECE_VALUE[pcAdjust][SQUARE_FLIP(sq)];
      pcAdjust += 7;
    }
    this.zobristKey ^= PreGen_zobristKeyTable[pcAdjust][sq];
    this.zobristLock ^= PreGen_zobristLockTable[pcAdjust][sq];
  }
  public pushMvList(mv){
    // var sqSrc = SRC(mv);
    // var sqDst = DST(mv);
    this.mvList.push(mv);
    this.distance ++;
  }
  private movePiece(mv) {
    var sqSrc = SRC(mv);
    var sqDst = DST(mv);
    var pc = this.squares[sqDst];
    this.pcList.push(pc);
    if (pc > 0) {
      this.addPiece(sqDst, pc, DEL_PIECE);
    }
    pc = this.squares[sqSrc];
    if(pc==0){
      console.log("pc error == ",this.squares,sqDst)
    }else{
      this.addPiece(sqSrc, pc, DEL_PIECE);
      this.addPiece(sqDst, pc, ADD_PIECE);
    }
    this.mvList.push(mv);
  }
  
  private undoMovePiece() {
    var mv = this.mvList.pop();
    var sqSrc = SRC(mv);
    var sqDst = DST(mv);
    var pc = this.squares[sqDst];
    this.addPiece(sqDst, pc, DEL_PIECE);
    this.addPiece(sqSrc, pc, ADD_PIECE);
    pc = this.pcList.pop();
    if (pc > 0) {
      this.addPiece(sqDst, pc, ADD_PIECE);
    }
  }
  
  public changeSide() {
    this.sdPlayer = 1 - this.sdPlayer;
    this.zobristKey ^= PreGen_zobristKeyPlayer;
    this.zobristLock ^= PreGen_zobristLockPlayer;
  }
  
  public makeMove(mv) {
    var zobristKey = this.zobristKey;
    this.movePiece(mv);
      // 检查走棋是否被将军。如果是，说明这是在送死，撤销走棋并返回false。
    if (this.checked()) {
      this.undoMovePiece(); // 撤销棋子移动
      return false;
    }
    this.keyList.push(zobristKey);
    this.changeSide();
    this.chkList.push(this.checked());
    this.distance ++;
    return true;
  }
  
  public undoMakeMove() {
    this.distance --;
    this.chkList.pop();
    this.changeSide();
    this.keyList.pop();
    this.undoMovePiece();
  }
  
  public nullMove() {
    this.mvList.push(0);
    this.pcList.push(0);
    this.keyList.push(this.zobristKey);
    this.changeSide();
    this.chkList.push(false);
    this.distance ++;
  }
  
  public undoNullMove() {
    this.distance --;
    this.chkList.pop();
    this.changeSide();
    this.keyList.pop();
    this.pcList.pop();
    this.mvList.pop();
  }
  //通过FEN串初始化棋局，也就是将参数fen表示的棋局，转化为一维棋局数组squares表示的棋局。
  public fromFen(fen) {
    this.clearBoard();
    var y = RANK_TOP;
    var x = FILE_LEFT;
    var index = 0;
    if (index == fen.length) {
      this.setIrrev();
      return;
    }
    var c = fen.charAt(index);
    while (c != " ") {
      if (c == "/") {
        x = FILE_LEFT;
        y ++;
        if (y > RANK_BOTTOM) {
          break;
        }
      } else if (c >= "1" && c <= "9") {
        x += (ASC(c) - ASC("0"));
      } else if (c >= "A" && c <= "Z") {
        if (x <= FILE_RIGHT) {
          var pt = CHAR_TO_PIECE(c);
          if (pt >= 0) {
            this.addPiece(COORD_XY(x, y), pt + 8,null);
          }
          x ++;
        }
      } else if (c >= "a" && c <= "z") {
        if (x <= FILE_RIGHT) {
          var pt = CHAR_TO_PIECE(CHR(ASC(c) + ASC("A") - ASC("a")));
          if (pt >= 0) {
            this.addPiece(COORD_XY(x, y), pt + 16,null);
          }
          x ++;
        }
      }
      index ++;
      if (index == fen.length) {
        this.setIrrev();
        return;
      }
      c = fen.charAt(index);
    }
    index ++;
    if (index == fen.length) {
      this.setIrrev();
      return;
    }
    if (this.sdPlayer == (fen.charAt(index) == "b" ? 0 : 1)) {
      this.changeSide();
    }
    this.setIrrev();
  }
  
  public toFen() {
    var fen = "";
    for (var y = RANK_TOP; y <= RANK_BOTTOM; y ++) {
      var k = 0;
      for (var x = FILE_LEFT; x <= FILE_RIGHT; x ++) {
        var pc = this.squares[COORD_XY(x, y)];
        if (pc > 0) {
          if (k > 0) {
            fen += CHR(ASC("0") + k);
            k = 0;
          }
          fen += FEN_PIECE.charAt(pc);
        } else {
          k ++;
        }
      }
      if (k > 0) {
        fen += CHR(ASC("0") + k);
      }
      fen += "/";
    }
    return fen.substring(0, fen.length - 1) +
        (this.sdPlayer == 0 ? " w" : " b");
  }
  
  public generateMoves(vls) {
    var mvs = [];
    var pcSelfSide = SIDE_TAG(this.sdPlayer);
    var pcOppSide = OPP_SIDE_TAG(this.sdPlayer);
    for (var sqSrc = 0; sqSrc < 256; sqSrc ++) {
      var pcSrc = this.squares[sqSrc];
      if ((pcSrc & pcSelfSide) == 0) {
        continue;
      }
      switch (pcSrc - pcSelfSide) {
      case PIECE_KING:
        for (var i = 0; i < 4; i ++) {
          var sqDst = sqSrc + KING_DELTA[i];
          if (!IN_FORT(sqDst)) {
            continue;
          }
          var pcDst = this.squares[sqDst];
          if (vls == null) {
            if ((pcDst & pcSelfSide) == 0) {
              mvs.push(MOVE(sqSrc, sqDst));
            }
          } else if ((pcDst & pcOppSide) != 0) {
            mvs.push(MOVE(sqSrc, sqDst));
            vls.push(MVV_LVA(pcDst, 5));
          }
        }
        break;
      case PIECE_ADVISOR:
        for (var i = 0; i < 4; i ++) {
          var sqDst = sqSrc + ADVISOR_DELTA[i];
          if (!IN_FORT(sqDst)) {
            continue;
          }
          var pcDst = this.squares[sqDst];
          if (vls == null) {
            if ((pcDst & pcSelfSide) == 0) {
              mvs.push(MOVE(sqSrc, sqDst));
            }
          } else if ((pcDst & pcOppSide) != 0) {
            mvs.push(MOVE(sqSrc, sqDst));
            vls.push(MVV_LVA(pcDst, 1));
          }
        }
        break;
      case PIECE_BISHOP:
        for (var i = 0; i < 4; i ++) {
          var sqDst = sqSrc + ADVISOR_DELTA[i];
          if (!(IN_BOARD(sqDst) && HOME_HALF(sqDst, this.sdPlayer) &&
              this.squares[sqDst] == 0)) {
            continue;
          }
          sqDst += ADVISOR_DELTA[i];
          var pcDst = this.squares[sqDst];
          if (vls == null) {
            if ((pcDst & pcSelfSide) == 0) {
              mvs.push(MOVE(sqSrc, sqDst));
            }
          } else if ((pcDst & pcOppSide) != 0) {
            mvs.push(MOVE(sqSrc, sqDst));
            vls.push(MVV_LVA(pcDst, 1));
          }
        }
        break;
      case PIECE_KNIGHT:
        for (var i = 0; i < 4; i ++) {
          var sqDst = sqSrc + KING_DELTA[i];
          if (this.squares[sqDst] > 0) {
            continue;
          }
          for (var j = 0; j < 2; j ++) {
            sqDst = sqSrc + KNIGHT_DELTA[i][j];
            if (!IN_BOARD(sqDst)) {
              continue;
            }
            var pcDst = this.squares[sqDst];
            if (vls == null) {
              if ((pcDst & pcSelfSide) == 0) {
                mvs.push(MOVE(sqSrc, sqDst));
              }
            } else if ((pcDst & pcOppSide) != 0) {
              mvs.push(MOVE(sqSrc, sqDst));
              vls.push(MVV_LVA(pcDst, 1));
            }
          }
        }
        break;
      case PIECE_ROOK:
        for (var i = 0; i < 4; i ++) {
          var delta = KING_DELTA[i];
          var sqDst = sqSrc + delta;
          while (IN_BOARD(sqDst)) {
            var pcDst = this.squares[sqDst];
            if (pcDst == 0) {
              if (vls == null) {
                mvs.push(MOVE(sqSrc, sqDst));
              }
            } else {
              if ((pcDst & pcOppSide) != 0) {
                mvs.push(MOVE(sqSrc, sqDst));
                if (vls != null) {
                  vls.push(MVV_LVA(pcDst, 4));
                }
              }
              break;
            }
            sqDst += delta;
          }
        }
        break;
      case PIECE_CANNON:
        for (var i = 0; i < 4; i ++) {
          var delta = KING_DELTA[i];
          var sqDst = sqSrc + delta;
          while (IN_BOARD(sqDst)) {
            var pcDst = this.squares[sqDst];
            if (pcDst == 0) {
              if (vls == null) {
                mvs.push(MOVE(sqSrc, sqDst));
              }
            } else {
              break;
            }
            sqDst += delta;
          }
          sqDst += delta;
          while (IN_BOARD(sqDst)) {
            var pcDst = this.squares[sqDst];
            if (pcDst > 0) {
              if ((pcDst & pcOppSide) != 0) {
                mvs.push(MOVE(sqSrc, sqDst));
                if (vls != null) {
                  vls.push(MVV_LVA(pcDst, 4));
                }
              }
              break;
            }
            sqDst += delta;
          }
        }
        break;
      case PIECE_PAWN:
        var sqDst = SQUARE_FORWARD(sqSrc, this.sdPlayer);
        if (IN_BOARD(sqDst)) {
          var pcDst = this.squares[sqDst];
          if (vls == null) {
            if ((pcDst & pcSelfSide) == 0) {
              mvs.push(MOVE(sqSrc, sqDst));
            }
          } else if ((pcDst & pcOppSide) != 0) {
            mvs.push(MOVE(sqSrc, sqDst));
            vls.push(MVV_LVA(pcDst, 2));
          }
        }
        if (AWAY_HALF(sqSrc, this.sdPlayer)) {
          for (var delta = -1; delta <= 1; delta += 2) {
            sqDst = sqSrc + delta;
            if (IN_BOARD(sqDst)) {
              var pcDst = this.squares[sqDst];
              if (vls == null) {
                if ((pcDst & pcSelfSide) == 0) {
                  mvs.push(MOVE(sqSrc, sqDst));
                }
              } else if ((pcDst & pcOppSide) != 0) {
                mvs.push(MOVE(sqSrc, sqDst));
                vls.push(MVV_LVA(pcDst, 2));
              }
            }
          }
        }
        break;
      }
    }
    return mvs;
  }
  public findAllCanMove(sq){
    var sqSrc = sq;
    var pcSrc = this.squares[sqSrc];
    var temp_array = [];
    var pcSelfSide = SIDE_TAG(this.sdPlayer);
    var pcOppSide = OPP_SIDE_TAG(this.sdPlayer);
    if ((pcSrc & pcSelfSide) == 0) {
      return temp_array;
    }
    switch (pcSrc - pcSelfSide) {
      case PIECE_KING: //寻找当前将所有可以走的路
      {
        var des_array = []
        des_array.push(sqSrc - 16)
        des_array.push(sqSrc - 1)
        des_array.push(sqSrc + 16)
        des_array.push(sqSrc + 1)
        for(var i=0;i<des_array.length;i++){
          if(IN_BOARD(des_array[i])){
            var b =this.legalMove(MOVE(sqSrc,des_array[i]))
            if(b){
              temp_array.push(des_array[i])
            }
          }
        }
      }
      break;
      case PIECE_ADVISOR:// 寻找当前士所有可以走的路
      {
        var des_array = []
        des_array.push(sqSrc - 17)
        des_array.push(sqSrc - 15)
        des_array.push(sqSrc + 17)
        des_array.push(sqSrc + 15)
        for(var i=0;i<des_array.length;i++){
          if(IN_BOARD(des_array[i])){
            var b =this.legalMove(MOVE(sqSrc,des_array[i]))
            if(b){
              temp_array.push(des_array[i])
            }
          }
        }
      }
      break;
      case PIECE_BISHOP: // 寻找当前象所有可以走的路
      {
        var des_array = []
        des_array.push(sqSrc - 34)
        des_array.push(sqSrc - 30)
        des_array.push(sqSrc + 30)
        des_array.push(sqSrc + 34)
        for(var i=0;i<des_array.length;i++){
          if(IN_BOARD(des_array[i])){
            var b =this.legalMove(MOVE(sqSrc,des_array[i]))
            if(b){
              temp_array.push(des_array[i])
            }
          }
        }
      }
      break;
      case PIECE_KNIGHT:// 寻找当前马所有可以走的路
      {
        var des_array = []
        des_array.push(sqSrc - 33)
        des_array.push(sqSrc - 31)
        des_array.push(sqSrc - 18)
        des_array.push(sqSrc + 14)
        des_array.push(sqSrc - 14)
        des_array.push(sqSrc + 18)
        des_array.push(sqSrc + 31)
        des_array.push(sqSrc + 33)
        for(var i=0;i<des_array.length;i++){
          if(IN_BOARD(des_array[i])){
            var b =this.legalMove(MOVE(sqSrc,des_array[i]))
            if(b){
              temp_array.push(des_array[i])
            }
          }
        }
      }
      break;
      case PIECE_CANNON:
      case PIECE_ROOK: //寻找当前 车 所有可以走的路
      {
        //var des_array = []
        //遍历列
        var left_index = 1;
        var isCannon = false;
        while (IN_BOARD(sqSrc-left_index)) {
          var pcLeftDst = this.squares[sqSrc-left_index]; //
          if(pcLeftDst!=0){
            if ((pcLeftDst & pcSelfSide) != 0) {
              //说明找到自己的棋子
              if((pcSrc - pcSelfSide) ==PIECE_ROOK ||isCannon){
                break;
              }else{
                isCannon = true;
              }
             
            }else if((pcLeftDst & pcOppSide) != 0){
              //说明找到敌方的棋子
              if((pcSrc - pcSelfSide) ==PIECE_ROOK){
                temp_array.push(sqSrc-left_index)
                break;
              }else{
                if(isCannon){
                  temp_array.push(sqSrc-left_index)
                  break;
                }else{
                  isCannon = true;
                }
              }
            }
          }else{
            if(!isCannon){
              temp_array.push(sqSrc-left_index)
            }
          }
          left_index++;
        }
        var right_index = 1;
        isCannon = false;
        while (IN_BOARD(sqSrc+right_index)) {
          var pcRightDst = this.squares[sqSrc+right_index]; //
          if(pcRightDst!=0){
            if ((pcRightDst & pcSelfSide) != 0) {
              //说明找到自己的棋子
              if((pcSrc - pcSelfSide) ==PIECE_ROOK ||isCannon){
                break;
              }else{
                isCannon = true;
              }
            }else if((pcRightDst & pcOppSide) != 0){
              //说明找到敌方的棋子
              if((pcSrc - pcSelfSide) ==PIECE_ROOK){
                temp_array.push(sqSrc+right_index)
                break;
              }else{
                if(isCannon){
                  temp_array.push(sqSrc+right_index)
                  break;
                }else{
                  isCannon = true;
                }
              }
            }
          }else{
            if(!isCannon){
              temp_array.push(sqSrc+right_index)
            }
          }
          right_index++;
        }

        //遍历行
        var top_index = 16;
        isCannon = false;
        while (IN_BOARD(sqSrc-top_index)) {
            var pcTopDst = this.squares[sqSrc-top_index]; //
            if(pcTopDst!=0){
              if ((pcTopDst & pcSelfSide) != 0) {
                //说明找到自己的棋子
                if((pcSrc - pcSelfSide) ==PIECE_ROOK ||isCannon){
                  break;
                }else{
                  isCannon = true;
                }
              }else if((pcTopDst & pcOppSide) != 0){
                //说明找到敌方的棋子
                if((pcSrc - pcSelfSide) ==PIECE_ROOK){
                  temp_array.push(sqSrc-top_index)
                  break;
                }else{
                  if(isCannon){
                    temp_array.push(sqSrc-top_index)
                    break;
                  }else{
                    isCannon = true;
                  }
                }
              }
            }else{
              if(!isCannon){
                temp_array.push(sqSrc-top_index)
              }
            }
            top_index+=16; 
        }
        var bottom_index = 16;
        isCannon = false;
        while (IN_BOARD(sqSrc+bottom_index)) {
          var pcBottomDst = this.squares[sqSrc+bottom_index]; //
          if(pcBottomDst!=0){
            if ((pcBottomDst & pcSelfSide) != 0) {
              //说明找到自己的棋子
              if((pcSrc - pcSelfSide) ==PIECE_ROOK ||isCannon){
                break;
              }else{
                isCannon = true;
              }
            }else if((pcBottomDst & pcOppSide) != 0){
              //说明找到敌方的棋子
              if((pcSrc - pcSelfSide) ==PIECE_ROOK){
                temp_array.push(sqSrc+bottom_index)
                break;
              }else{
                if(isCannon){
                  temp_array.push(sqSrc+bottom_index)
                  break;
                }else{
                  isCannon = true;
                }
              }
            }
          }else{
            if(!isCannon){
              temp_array.push(sqSrc+bottom_index)
            }
          }
          bottom_index+=16; 
        }
      }
      break;

      case PIECE_PAWN: //寻找当前卒 所有可以走的路
      {
        var des_array = []
        des_array.push(sqSrc - 16)
        des_array.push(sqSrc - 1)
        des_array.push(sqSrc + 16)
        des_array.push(sqSrc + 1)
        for(i=0;i<des_array.length;i++){
          if(IN_BOARD(des_array[i])){
            var b =this.legalMove(MOVE(sqSrc,des_array[i]))
            if(b){
              temp_array.push(des_array[i])
            }
          }
        }
      }
      break;
      default:
        return temp_array;
    }
    return temp_array;
  }
  //判断步骤是否合法。合法返回true，非法返回false。
  public legalMove(mv) {
    var sqSrc = SRC(mv);
    var pcSrc = this.squares[sqSrc];
    var pcSelfSide = SIDE_TAG(this.sdPlayer);
    if ((pcSrc & pcSelfSide) == 0) {
      return false;
    }
  
    var sqDst = DST(mv);
    var pcDst = this.squares[sqDst];
    if ((pcDst & pcSelfSide) != 0) {
      return false;
    }
  
    switch (pcSrc - pcSelfSide) {
    case PIECE_KING:
      return IN_FORT(sqDst) && KING_SPAN(sqSrc, sqDst);
    case PIECE_ADVISOR:
      return IN_FORT(sqDst) && ADVISOR_SPAN(sqSrc, sqDst);
    case PIECE_BISHOP:
      return SAME_HALF(sqSrc, sqDst) && BISHOP_SPAN(sqSrc, sqDst) &&
          this.squares[BISHOP_PIN(sqSrc, sqDst)] == 0;
    case PIECE_KNIGHT:
      var sqPin = KNIGHT_PIN(sqSrc, sqDst);
      return sqPin != sqSrc && this.squares[sqPin] == 0;
    case PIECE_ROOK:
    case PIECE_CANNON:
      var delta;
      if (SAME_RANK(sqSrc, sqDst)) {
        delta = (sqDst < sqSrc ? -1 : 1);
      } else if (SAME_FILE(sqSrc, sqDst)) {
        delta = (sqDst < sqSrc ? -16 : 16);
      } else {
        return false;
      }
      var sqPin = sqSrc + delta;
      while (sqPin != sqDst && this.squares[sqPin] == 0) {
        sqPin += delta;
      }
      if (sqPin == sqDst) {
        return pcDst == 0 || pcSrc - pcSelfSide == PIECE_ROOK;
      }
      if (pcDst == 0 || pcSrc - pcSelfSide != PIECE_CANNON) {
        return false;
      }
      sqPin += delta;
      while (sqPin != sqDst && this.squares[sqPin] == 0) {
        sqPin += delta;
      }
      return sqPin == sqDst;
    case PIECE_PAWN:
      if (AWAY_HALF(sqDst, this.sdPlayer) && (sqDst == sqSrc - 1 || sqDst == sqSrc + 1)) {
        return true;
      }
      return sqDst == SQUARE_FORWARD(sqSrc, this.sdPlayer);
    default:
      return false;
    }
  }
  
  private checked() {
    var pcSelfSide = SIDE_TAG(this.sdPlayer);
    var pcOppSide = OPP_SIDE_TAG(this.sdPlayer);
    for (var sqSrc = 0; sqSrc < 256; sqSrc ++) {
      if (this.squares[sqSrc] != pcSelfSide + PIECE_KING) {
        continue;
      }
      if (this.squares[SQUARE_FORWARD(sqSrc, this.sdPlayer)] == pcOppSide + PIECE_PAWN) {
        return true;
      }
      for (var delta = -1; delta <= 1; delta += 2) {
        if (this.squares[sqSrc + delta] == pcOppSide + PIECE_PAWN) {
          return true;
        }
      }
      for (var i = 0; i < 4; i ++) {
        if (this.squares[sqSrc + ADVISOR_DELTA[i]] != 0) {
          continue;
        }
        for (var j = 0; j < 2; j ++) {
          var pcDst = this.squares[sqSrc + KNIGHT_CHECK_DELTA[i][j]];
          if (pcDst == pcOppSide + PIECE_KNIGHT) {
            return true;
          }
        }
      }
      for (var i = 0; i < 4; i ++) {
        var delta = KING_DELTA[i];
        var sqDst = sqSrc + delta;
        while (IN_BOARD(sqDst)) {
          var pcDst = this.squares[sqDst];
          if (pcDst > 0) {
            if (pcDst == pcOppSide + PIECE_ROOK || pcDst == pcOppSide + PIECE_KING) {
              return true;
            }
            break;
          }
          sqDst += delta;
        }
        sqDst += delta;
        while (IN_BOARD(sqDst)) {
          var pcDst = this.squares[sqDst];
          if (pcDst > 0) {
            if (pcDst == pcOppSide + PIECE_CANNON) {
              return true;
            }
            break;
          }
          sqDst += delta;
        }
      }
      return false;
    }
    return false;
  }
  
   isMate() {
    var mvs = this.generateMoves(null);
    for (var i = 0; i < mvs.length; i ++) {
      if (this.makeMove(mvs[i])) {
        this.undoMakeMove();
        return false;
      }
    }
    return true;
  }
  
   mateValue() {
    return this.distance - MATE_VALUE;
  }
  
   banValue() {
    return this.distance - BAN_VALUE;
  }
  
   drawValue() {
    return (this.distance & 1) == 0 ? -DRAW_VALUE : DRAW_VALUE;
  }
  
   evaluate() {
    var vl = (this.sdPlayer == 0 ? this.vlWhite - this.vlBlack :
        this.vlBlack - this.vlWhite) + ADVANCED_VALUE;
    return vl == this.drawValue() ? vl - 1 : vl;
  }
  
  nullOkay() {
    return (this.sdPlayer == 0 ? this.vlWhite : this.vlBlack) > NULL_OKAY_MARGIN;
  }
  
   nullSafe() {
    return (this.sdPlayer == 0 ? this.vlWhite : this.vlBlack) > NULL_SAFE_MARGIN;
  }
  
   inCheck() {
    return this.chkList[this.chkList.length - 1];
  }
  
   captured() {
    return this.pcList[this.pcList.length - 1] > 0;
  }
  
   repValue(vlRep) {
    var vlReturn = ((vlRep & 2) == 0 ? 0 : this.banValue()) +
        ((vlRep & 4) == 0 ? 0 : -this.banValue());
    return vlReturn == 0 ? this.drawValue() : vlReturn;
  }
  
  repStatus(recur_) {
    var recur = recur_;
    var selfSide = false;
    var perpCheck = true;
    var oppPerpCheck = true;
    var index = this.mvList.length - 1;
    while (this.mvList[index] > 0 && this.pcList[index] == 0) {
      if (selfSide) {
        perpCheck = perpCheck && this.chkList[index];
        if (this.keyList[index] == this.zobristKey) {
          recur --;
          if (recur == 0) {
            return 1 + (perpCheck ? 2 : 0) + (oppPerpCheck ? 4 : 0);
          }
        }
      } else {
        oppPerpCheck = oppPerpCheck && this.chkList[index];
      }
      selfSide = !selfSide;
      index --;
    }
    return 0;
  }
  
  mirror() {
    var pos = new ChessPos();
    pos.clearBoard();
    for (var sq = 0; sq < 256; sq ++) {
      var pc = this.squares[sq];
      if (pc > 0) {
         pos.addPiece(MIRROR_SQUARE(sq), pc,null);
      }
    }
    if (this.sdPlayer == 1) {
      pos.changeSide();
    }
    return pos;
  }
  
  bookMove() {

    return 0;
    // if (typeof BOOK_DAT != "object" || BOOK_DAT.length == 0) {
    //   return 0;
    // }
    // var mirror = false;
    // var lock = this.zobristLock >>> 1; // Convert into Unsigned
    // var index = binarySearch(BOOK_DAT, lock);
    // if (index < 0) {
    //   mirror = true;
    //   lock = this.mirror().zobristLock >>> 1; // Convert into Unsigned
    //   index = binarySearch(BOOK_DAT, lock);
    // }
    // if (index < 0) {
    //   return 0;
    // }
    // index --;
    // while (index >= 0 && BOOK_DAT[index][0] == lock) {
    //   index --;
    // }
    // var mvs = [], vls = [];
    // var value = 0;
    // index ++;
    // while (index < BOOK_DAT.length && BOOK_DAT[index][0] == lock) {
    //   var mv = BOOK_DAT[index][1];
    //   mv = (mirror ? MIRROR_MOVE(mv) : mv);
    //   if (this.legalMove(mv)) {
    //     mvs.push(mv);
    //     var vl = BOOK_DAT[index][2];
    //     vls.push(vl);
    //     value += vl;
    //   }
    //   index ++;
    // }
    // if (value == 0) {
    //   return 0;
    // }
    // value = Math.floor(Math.random() * value);
    // for (index = 0; index < mvs.length; index ++) {
    //   value -= vls[index];
    //   if (value < 0) {
    //     break;
    //   }
    // }
    // return mvs[index];
  }
  
   historyIndex(mv) {
    return ((this.squares[SRC(mv)] - 8) << 8) + DST(mv);
  }
}

function binarySearch(vlss, vl) {
  var low = 0;
  var high = vlss.length - 1;
  while (low <= high) {
    var mid = (low + high) >> 1;
    if (vlss[mid][0] < vl) {
      low = mid + 1;
    } else if (vlss[mid][0] > vl) {
      high = mid - 1;
    } else {
      return mid;
    }
  }
  return -1;
}

var MATE_VALUE = 10000;
var BAN_VALUE = MATE_VALUE - 100;
var WIN_VALUE = MATE_VALUE - 200;
var NULL_SAFE_MARGIN = 400;
var NULL_OKAY_MARGIN = 200;
var DRAW_VALUE = 20;
var ADVANCED_VALUE = 3;
	/** !#en This is a KING.
	!#zh 这是一个 將  */
var PIECE_KING = 0;
	/** !#en This is a ADVISOR.
	!#zh 这是一个 士  */
var PIECE_ADVISOR = 1;
	/** !#en This is a BISHOP.
	!#zh 这是一个 象  */
var PIECE_BISHOP = 2;
	/** !#en This is a KNIGHT.
	!#zh 这是一个 馬  */
var PIECE_KNIGHT = 3;
	/** !#en This is a ROOK.
	!#zh 这是一个 车  */
var PIECE_ROOK = 4;// 车
	/** !#en This is a CANNON.
	!#zh 这是一个 炮  */
var PIECE_CANNON = 5;
	/** !#en This is a PAWN.
	!#zh 这是一个 卒  */
var PIECE_PAWN = 6;

var RANK_TOP = 3;
var RANK_BOTTOM = 12;
var FILE_LEFT = 3;
var FILE_RIGHT = 11;

var ADD_PIECE = false;
var DEL_PIECE = true;
	/** !#en This is a init board 16*16 size.
	!#zh 这是一个初始棋盤的大小 在程序中，棋局被表示为大小为256的一维数组，一半棋盘位于0到127，另一半位于128到255。
128的二进制是1000 0000，右起第八位是1。128到255这些数的二进制，右起第8位都是1；0到127这些数的二进制，右起第8位都是0。  */
var IN_BOARD_ = [
 /* 0 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, //15
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, //31
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, //47
  0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0,
  0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0,
  0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0,
  0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0,
  0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, /* 127 */
  0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0,
  0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0,
  0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0,
  0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0,
  0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 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, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,/* 255 */
];

var IN_FORT_ = [
  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,
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 1, 1, 1, 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, 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, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 1, 1, 1, 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, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
];

var LEGAL_SPAN = [
                       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, 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, 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, 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, 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, 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, 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, 3, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 2, 1, 2, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 2, 1, 2, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 3, 0, 0, 0, 3, 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, 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, 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, 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, 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, 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, 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,
];

var KNIGHT_PIN_ = [
                              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,  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,  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,  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,  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,  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,  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,-16,  0,-16,  0,  0,  0,  0,  0,  0,  0,
  0,  0,  0,  0,  0, -1,  0,  0,  0,  1,  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, -1,  0,  0,  0,  1,  0,  0,  0,  0,  0,  0,
  0,  0,  0,  0,  0,  0, 16,  0, 16,  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,  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,  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,  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,  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,  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,  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,
];

var KING_DELTA = [-16, -1, 1, 16];
var ADVISOR_DELTA = [-17, -15, 15, 17];
var KNIGHT_DELTA = [[-33, -31], [-18, 14], [-14, 18], [31, 33]];
var KNIGHT_CHECK_DELTA = [[-33, -18], [-31, -14], [14, 31], [18, 33]];
var MVV_VALUE = [50, 10, 10, 30, 40, 30, 20, 0];

var PIECE_VALUE = [
  [
    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,
    0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
    0,  0,  0,  9,  9,  9, 11, 13, 11,  9,  9,  9,  0,  0,  0,  0,
    0,  0,  0, 19, 24, 34, 42, 44, 42, 34, 24, 19,  0,  0,  0,  0,
    0,  0,  0, 19, 24, 32, 37, 37, 37, 32, 24, 19,  0,  0,  0,  0,
    0,  0,  0, 19, 23, 27, 29, 30, 29, 27, 23, 19,  0,  0,  0,  0,
    0,  0,  0, 14, 18, 20, 27, 29, 27, 20, 18, 14,  0,  0,  0,  0,
    0,  0,  0,  7,  0, 13,  0, 16,  0, 13,  0,  7,  0,  0,  0,  0,
    0,  0,  0,  7,  0,  7,  0, 15,  0,  7,  0,  7,  0,  0,  0,  0,
    0,  0,  0,  0,  0,  0,  1,  1,  1,  0,  0,  0,  0,  0,  0,  0,
    0,  0,  0,  0,  0,  0,  2,  2,  2,  0,  0,  0,  0,  0,  0,  0,
    0,  0,  0,  0,  0,  0, 11, 15, 11,  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,  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,  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,  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,  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,  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, 20,  0,  0,  0, 20,  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, 18,  0,  0, 20, 23, 20,  0,  0, 18,  0,  0,  0,  0,
    0,  0,  0,  0,  0,  0,  0, 23,  0,  0,  0,  0,  0,  0,  0,  0,
    0,  0,  0,  0,  0, 20, 20,  0, 20, 20,  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,  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,  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,  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,  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,  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, 20,  0,  0,  0, 20,  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, 18,  0,  0, 20, 23, 20,  0,  0, 18,  0,  0,  0,  0,
    0,  0,  0,  0,  0,  0,  0, 23,  0,  0,  0,  0,  0,  0,  0,  0,
    0,  0,  0,  0,  0, 20, 20,  0, 20, 20,  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,  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,  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,  0,  0,  0,  0,  0,  0,
    0,  0,  0, 90, 90, 90, 96, 90, 96, 90, 90, 90,  0,  0,  0,  0,
    0,  0,  0, 90, 96,103, 97, 94, 97,103, 96, 90,  0,  0,  0,  0,
    0,  0,  0, 92, 98, 99,103, 99,103, 99, 98, 92,  0,  0,  0,  0,
    0,  0,  0, 93,108,100,107,100,107,100,108, 93,  0,  0,  0,  0,
    0,  0,  0, 90,100, 99,103,104,103, 99,100, 90,  0,  0,  0,  0,
    0,  0,  0, 90, 98,101,102,103,102,101, 98, 90,  0,  0,  0,  0,
    0,  0,  0, 92, 94, 98, 95, 98, 95, 98, 94, 92,  0,  0,  0,  0,
    0,  0,  0, 93, 92, 94, 95, 92, 95, 94, 92, 93,  0,  0,  0,  0,
    0,  0,  0, 85, 90, 92, 93, 78, 93, 92, 90, 85,  0,  0,  0,  0,
    0,  0,  0, 88, 85, 90, 88, 90, 88, 90, 85, 88,  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,  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,  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,  0,  0,  0,  0,
    0,  0,  0,206,208,207,213,214,213,207,208,206,  0,  0,  0,  0,
    0,  0,  0,206,212,209,216,233,216,209,212,206,  0,  0,  0,  0,
    0,  0,  0,206,208,207,214,216,214,207,208,206,  0,  0,  0,  0,
    0,  0,  0,206,213,213,216,216,216,213,213,206,  0,  0,  0,  0,
    0,  0,  0,208,211,211,214,215,214,211,211,208,  0,  0,  0,  0,
    0,  0,  0,208,212,212,214,215,214,212,212,208,  0,  0,  0,  0,
    0,  0,  0,204,209,204,212,214,212,204,209,204,  0,  0,  0,  0,
    0,  0,  0,198,208,204,212,212,212,204,208,198,  0,  0,  0,  0,
    0,  0,  0,200,208,206,212,200,212,206,208,200,  0,  0,  0,  0,
    0,  0,  0,194,206,204,212,200,212,204,206,194,  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,  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,  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,  0,  0,  0,  0,
    0,  0,  0,100,100, 96, 91, 90, 91, 96,100,100,  0,  0,  0,  0,
    0,  0,  0, 98, 98, 96, 92, 89, 92, 96, 98, 98,  0,  0,  0,  0,
    0,  0,  0, 97, 97, 96, 91, 92, 91, 96, 97, 97,  0,  0,  0,  0,
    0,  0,  0, 96, 99, 99, 98,100, 98, 99, 99, 96,  0,  0,  0,  0,
    0,  0,  0, 96, 96, 96, 96,100, 96, 96, 96, 96,  0,  0,  0,  0,
    0,  0,  0, 95, 96, 99, 96,100, 96, 99, 96, 95,  0,  0,  0,  0,
    0,  0,  0, 96, 96, 96, 96, 96, 96, 96, 96, 96,  0,  0,  0,  0,
    0,  0,  0, 97, 96,100, 99,101, 99,100, 96, 97,  0,  0,  0,  0,
    0,  0,  0, 96, 97, 98, 98, 98, 98, 98, 97, 96,  0,  0,  0,  0,
    0,  0,  0, 96, 96, 97, 99, 99, 99, 97, 96, 96,  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,  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,  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,  0,  0,  0,  0,
    0,  0,  0,  9,  9,  9, 11, 13, 11,  9,  9,  9,  0,  0,  0,  0,
    0,  0,  0, 19, 24, 34, 42, 44, 42, 34, 24, 19,  0,  0,  0,  0,
    0,  0,  0, 19, 24, 32, 37, 37, 37, 32, 24, 19,  0,  0,  0,  0,
    0,  0,  0, 19, 23, 27, 29, 30, 29, 27, 23, 19,  0,  0,  0,  0,
    0,  0,  0, 14, 18, 20, 27, 29, 27, 20, 18, 14,  0,  0,  0,  0,
    0,  0,  0,  7,  0, 13,  0, 16,  0, 13,  0,  7,  0,  0,  0,  0,
    0,  0,  0,  7,  0,  7,  0, 15,  0,  7,  0,  7,  0,  0,  0,  0,
    0,  0,  0,  0,  0,  0,  1,  1,  1,  0,  0,  0,  0,  0,  0,  0,
    0,  0,  0,  0,  0,  0,  2,  2,  2,  0,  0,  0,  0,  0,  0,  0,
    0,  0,  0,  0,  0,  0, 11, 15, 11,  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,  0,  0,  0,  0,  0,  0,  0,
    0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
  ],
];

function IN_BOARD(sq) {
  return IN_BOARD_[sq] != 0;
}

function IN_FORT(sq) {
  return IN_FORT_[sq] != 0;
}

function RANK_Y(sq) {
  return sq >> 4;
}

function FILE_X(sq) {
  return sq & 15;
}
// 将二维矩阵转换为一维矩阵
function COORD_XY(x, y) {
  return x + (y << 4);
}

function SQUARE_FLIP(sq) {
  return 254 - sq;
}

function FILE_FLIP(x) {
  return 14 - x;
}

function RANK_FLIP(y) {
  return 15 - y;
}

function MIRROR_SQUARE(sq) {
  return COORD_XY(FILE_FLIP(FILE_X(sq)), RANK_Y(sq));
}

function SQUARE_FORWARD(sq, sd) {
  return sq - 16 + (sd << 5);
}

function KING_SPAN(sqSrc, sqDst) {
  return LEGAL_SPAN[sqDst - sqSrc + 256] == 1;
}

function ADVISOR_SPAN(sqSrc, sqDst) {
  return LEGAL_SPAN[sqDst - sqSrc + 256] == 2;
}

function BISHOP_SPAN(sqSrc, sqDst) {
  return LEGAL_SPAN[sqDst - sqSrc + 256] == 3;
}

function BISHOP_PIN(sqSrc, sqDst) {
  return (sqSrc + sqDst) >> 1;
}

function KNIGHT_PIN(sqSrc, sqDst) {
  return sqSrc + KNIGHT_PIN_[sqDst - sqSrc + 256];
}

function HOME_HALF(sq, sd) {
  return (sq & 0x80) != (sd << 7);
}

function AWAY_HALF(sq, sd) {
  return (sq & 0x80) == (sd << 7);
}
// 如果从起点sqSrc到终点sqDst没有过河，则返回true；否则返回false
function SAME_HALF(sqSrc, sqDst) {
  return ((sqSrc ^ sqDst) & 0x80) == 0;
}

function SAME_RANK(sqSrc, sqDst) {
  return ((sqSrc ^ sqDst) & 0xf0) == 0;
}

function SAME_FILE(sqSrc, sqDst) {
  return ((sqSrc ^ sqDst) & 0x0f) == 0;
}

function SIDE_TAG(sd) {
  return 8 + (sd << 3);
}

function OPP_SIDE_TAG(sd) {
  return 16 - (sd << 3);
}

function SRC(mv) {
  return mv & 255;
}

function DST(mv) {
  return mv >> 8;
}

function MOVE(sqSrc, sqDst) {
  return sqSrc + (sqDst << 8);
}

function MIRROR_MOVE(mv) {
  return MOVE(MIRROR_SQUARE(SRC(mv)), MIRROR_SQUARE(DST(mv)));
}

function MVV_LVA(pc, lva) {
  return MVV_VALUE[pc & 7] - lva;
}

function CHR(n) {
  return String.fromCharCode(n);
}

function ASC(c) {
  return c.charCodeAt(0);
}

var FEN_PIECE = "        KABNRCP kabnrcp ";

function CHAR_TO_PIECE(c) {
  switch (c) {
  case "K":
    return PIECE_KING; // 将
  case "A":
    return PIECE_ADVISOR; // 士
  case "B":
  case "E":
    return PIECE_BISHOP; // 象
  case "H":
  case "N":
    return PIECE_KNIGHT; // 马
  case "R":
    return PIECE_ROOK; // 车
  case "C":
    return PIECE_CANNON; // 炮
  case "P":
    return PIECE_PAWN; //卒
  default:
    return -1;
  }
}

function RC4(key) {
  this.x = this.y = 0;
  this.state = [];
  for (var i = 0; i < 256; i ++) {
    this.state.push(i);
  }
  var j = 0;
  for (var i = 0; i < 256; i ++) {
    j = (j + this.state[i] + key[i % key.length]) & 0xff;
    this.swap(i, j);
  }
}

RC4.prototype.swap = function(i, j) {
  var t = this.state[i];
  this.state[i] = this.state[j];
  this.state[j] = t;
}

RC4.prototype.nextByte = function() {
  this.x = (this.x + 1) & 0xff;
  this.y = (this.y + this.state[this.x]) & 0xff;
  this.swap(this.x, this.y);
  var t = (this.state[this.x] + this.state[this.y]) & 0xff;
  return this.state[t];
}

RC4.prototype.nextLong = function() {
  var n0 = this.nextByte();
  var n1 = this.nextByte();
  var n2 = this.nextByte();
  var n3 = this.nextByte();
  return n0 + (n1 << 8) + (n2 << 16) + ((n3 << 24) & 0xffffffff);
}

var PreGen_zobristKeyPlayer, PreGen_zobristLockPlayer;
var PreGen_zobristKeyTable = [], PreGen_zobristLockTable = [];

var rc4 = new RC4([0]);
PreGen_zobristKeyPlayer = rc4.nextLong();
rc4.nextLong();
PreGen_zobristLockPlayer = rc4.nextLong();
for (var i = 0; i < 14; i ++) {
  var keys = [];
  var locks = [];
  for (var j = 0; j < 256; j ++) {
    keys.push(rc4.nextLong());
    rc4.nextLong();
    locks.push(rc4.nextLong());
  }
  PreGen_zobristKeyTable.push(keys);
  PreGen_zobristLockTable.push(locks);
}

// function Position() {
//   // sdPlayer, zobristKey, zobristLock, vlWhite, vlBlack, distance;
//   // squares, mvList, pcList, keyList, chkList;
// }


//module.exports = Position;