StackAndCoquer new AI players

MinimaxCPU.js

/**
 * \file MinimaxCPU.js
 *
 * \section LICENSE
 *
 * Copyright (C) 2024 Maks Verver
 *
 * This file is part of StackAndConquer.
 *
 * StackAndConquer is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * StackAndConquer is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with StackAndConquer.  If not, see <https://www.gnu.org/licenses/>.
 *
 * \section DESCRIPTION
 *
 * CPU opponent using the Minimax algorithm.
 *
 * This file was auto-generated from multiple source files. The original source
 * code is available here: https://github.com/maksverver/stackandconquer-ai/
 */

'use strict';

// src/minimax.js
var SEARCH_DEPTH = 4;
function findBestMoves(unusedCfg, state, moves) {
  function search(depthLeft, alpha, beta) {
    if (depthLeft === 0) {
      return state.evaluate();
    }
    var moves2 = state.generateMoves();
    if (moves2.length === 0) {
      var value2 = state.evaluate();
      if (value2 > 0) value2 += depthLeft;
      if (value2 < 0) value2 -= depthLeft;
      return value2;
    }
    var bestValue2 = -Infinity;
    for (var i2 = 0; i2 < moves2.length; ++i2) {
      var move2 = moves2[i2];
      var undoState2 = state.doMove(move2);
      var value2 = -search(depthLeft - 1, -beta, -alpha);
      state.undoMove(move2, undoState2);
      if (value2 > bestValue2) {
        bestValue2 = value2;
        if (value2 > alpha) alpha = value2;
        if (value2 >= beta) break;
      }
    }
    return bestValue2;
  }
  var bestMoves = [];
  var bestValue = -Infinity;
  for (var i = 0; i < moves.length; ++i) {
    var move = moves[i];
    var undoState = state.doMove(move);
    var value = -search(SEARCH_DEPTH - 1, -Infinity, -bestValue + 1);
    state.undoMove(move, undoState);
    if (value > bestValue) {
      bestValue = value;
      bestMoves.length = 0;
    }
    if (value === bestValue) {
      bestMoves.push(move);
    }
  }
  return [bestMoves, bestValue];
}

// src/util.js
var log = typeof game === "object" ? game.log : console.log;
function createConfig(rows, cols, inputFields, outside, padding, paddingSize, winningHeight, playerCount) {
  var paddedRows = rows + 2 * paddingSize;
  var paddedCols = cols + 2 * paddingSize;
  if (inputFields.length !== paddedRows * paddedCols) {
    throw new Error("Invalid length of input fields");
  }
  var apiToFieldIndex = [];
  var fieldIndexToApi = [];
  var fieldCount = 0;
  for (var r1 = 0; r1 < paddedRows; ++r1) {
    for (var c1 = 0; c1 < paddedCols; ++c1) {
      var i = paddedCols * r1 + c1;
      if (inputFields[i] === outside || inputFields[i] === padding) {
        apiToFieldIndex.push(-1);
      } else {
        apiToFieldIndex.push(fieldCount++);
        fieldIndexToApi.push(i);
      }
    }
  }
  if (fieldCount > 30) {
    throw new Error("Too many fields (maximum supported: 30)");
  }
  var moves = [];
  var DR = [-1, -1, -1, 0, 0, 1, 1, 1];
  var DC = [-1, 0, 1, -1, 1, -1, 0, 1];
  for (var r2 = 0; r2 < paddedRows; ++r2) {
    for (var c2 = 0; c2 < paddedCols; ++c2) {
      var j = paddedCols * r2 + c2;
      if (inputFields[j] === outside || inputFields[j] === padding) continue;
      var dst = moves.length;
      moves.push([]);
      for (var height = 0; height < winningHeight; ++height) {
        moves[dst].push([]);
      }
      for (var dir = 0; dir < 8; ++dir) {
        var dr = DR[dir], dc = DC[dir];
        var mask = 0;
        for (var height = 1; height < winningHeight; ++height) {
          var r1 = r2 - dr * height;
          var c1 = c2 - dc * height;
          if (r1 < 0 || r1 >= paddedRows || c1 < 0 || c1 >= paddedCols) break;
          var i = paddedCols * r1 + c1;
          if (inputFields[i] === outside || inputFields[i] === padding) break;
          var src = apiToFieldIndex[i];
          moves[dst][height].push([src, mask]);
          mask |= 1 << src;
        }
      }
    }
  }
  return Object.freeze({
    apiToFieldIndex: Object.freeze(apiToFieldIndex),
    fieldIndexToApi: Object.freeze(fieldIndexToApi),
    fieldCount: fieldCount,
    moves: Object.freeze(moves),
    winningHeight: winningHeight,
    playerCount: playerCount,
    // These are only used for move parsing/formatting and debug printing:
    rows: rows,
    cols: cols,
    paddingSize: paddingSize
  });
}
function fieldIndexToRowCol(cfg2, index) {
  var i = cfg2.fieldIndexToApi[index];
  var pad = cfg2.paddingSize;
  var rowStride = pad * 2 + cfg2.cols;
  var col = i % rowStride;
  var row = (i - col) / rowStride;
  return [row - pad, col - pad];
}
function rowColToFieldIndex(cfg2, row, col) {
  var pad = cfg2.paddingSize;
  var rowStride = pad * 2 + cfg2.cols;
  var res = cfg2.apiToFieldIndex[rowStride * (row + pad) + (col + pad)];
  return res == null ? -1 : res;
}
function arrayOfValues(len, value) {
  var res = [];
  for (var i = 0; i < len; ++i) res.push(value);
  return res;
}
function arrayEquals(a, b) {
  if (a.length !== b.length) return false;
  for (var i = 0; i < a.length; ++i) if (a[i] !== b[i]) return false;
  return true;
}
function indexOfMove(moves, move) {
  for (var i = 0; i < moves.length; ++i) {
    if (arrayEquals(move, moves[i])) return i;
  }
  return -1;
}
function randomChoice(array) {
  return array[Math.floor(Math.random() * array.length)];
}

// src/formatting.js
function formatRow(row) {
  return String(row + 1);
}
function formatCol(col) {
  return String.fromCharCode("a".charCodeAt(0) + col);
}
function formatField(cfg2, field) {
  var coords = fieldIndexToRowCol(cfg2, field);
  return formatCol(coords[1]) + formatRow(coords[0]);
}
function formatMove(cfg2, move) {
  if (move.length === 0) return "pass";
  var src = move[0];
  var cnt = move[1];
  var dst = move[2];
  var res = "";
  if (cnt !== 1) res += String(cnt);
  if (src !== -1) res += formatField(cfg2, src);
  res += formatField(cfg2, dst);
  return res;
}
function formatMoves(cfg2, moves) {
  var res = "";
  for (var i = 0; i < moves.length; ++i) {
    if (i > 0) res += " ";
    res += formatMove(cfg2, moves[i]);
  }
  return res;
}

// src/State.js
var PASS = Object.freeze([]);
function cloneArray(arr) {
  return arr.slice();
}
function cloneFields(arr) {
  return arr.map(cloneArray);
}
function State(cfg2, fields, nextPlayer, lastMove, piecesLeft, scoresLeft, occupied) {
  function getNextPlayer() {
    return nextPlayer;
  }
  function getWinner() {
    return scoresLeft.indexOf(0);
  }
  function doMoveInternal(move) {
    var removed = null;
    if (move.length !== 0) {
      var src = move[0];
      var cnt = move[1];
      var dst = move[2];
      var dstField = fields[dst];
      if (src === -1) {
        --piecesLeft[nextPlayer];
        dstField.push(nextPlayer);
        occupied ^= 1 << dst;
      } else {
        var srcField = fields[src];
        dstField.push.apply(dstField, srcField.splice(srcField.length - cnt));
        if (srcField.length === 0) {
          occupied ^= 1 << src;
        }
        if (dstField.length >= cfg2.winningHeight) {
          removed = dstField.splice(0);
          var winner = removed[removed.length - 1];
          scoresLeft[winner] -= 1;
          occupied ^= 1 << dst;
          for (var i = 0; i < removed.length; ++i) ++piecesLeft[removed[i]];
        }
      }
      ++nextPlayer;
      if (nextPlayer === cfg2.playerCount) nextPlayer = 0;
      lastMove = move;
      return removed;
    }
  }
  function doMove(move) {
    return [lastMove, doMoveInternal(move)];
  }
  function undoMove(move, undoState) {
    if (nextPlayer === 0) nextPlayer = cfg2.playerCount;
    --nextPlayer;
    lastMove = undoState[0];
    if (move.length !== 0) {
      var src = move[0];
      var cnt = move[1];
      var dst = move[2];
      var dstField = fields[dst];
      if (src === -1) {
        ++piecesLeft[nextPlayer];
        dstField.pop();
        occupied ^= 1 << dst;
      } else {
        var srcField = fields[src];
        var removed = undoState[1];
        if (removed != null) {
          for (var i = 0; i < removed.length; ++i) --piecesLeft[removed[i]];
          var winner = removed[removed.length - 1];
          scoresLeft[winner] += 1;
          dstField.push.apply(dstField, removed);
          occupied ^= 1 << dst;
        }
        if (srcField.length === 0) {
          occupied ^= 1 << src;
        }
        srcField.push.apply(srcField, dstField.splice(dstField.length - cnt));
      }
    }
  }
  function evaluate() {
    var winner = getWinner();
    if (winner !== -1) return winner === nextPlayer ? 1e9 : -1e9;
    var score = 1e4 * (scoresLeft[1 - nextPlayer] - scoresLeft[nextPlayer]);
    for (var dst = 0; dst < fields.length; ++dst) {
      var dstField = fields[dst];
      var dstHeight = dstField.length;
      if (dstHeight > 0) {
        var options = cfg2.moves[dst][dstHeight];
        for (var i = 0; i < options.length; ++i) {
          var src = options[i][0];
          var srcField = fields[src];
          var srcHeight = srcField.length;
          if (srcHeight + dstHeight >= cfg2.winningHeight && (occupied & options[i][1]) === 0) {
            if (srcField[srcHeight - 1] === nextPlayer) {
              score += 1e3;
            } else {
              score -= 100;
            }
          }
        }
        if (dstField[dstHeight - 1] === nextPlayer) {
          score += 10 * dstHeight;
        } else {
          score -= 10 * dstHeight;
        }
        for (var i = 0; i < dstHeight; ++i) {
          if (dstField[i] === nextPlayer) {
            score += 1 + i;
          } else {
            score -= 1 + i;
          }
        }
      }
    }
    return score;
  }
  function generateMoves() {
    if (getWinner() !== -1) return [];
    var moveTemplates = cfg2.moves;
    var moves = [];
    var lastSrc = -1, lastCnt = 0, lastDst = -1;
    if (lastMove != null && lastMove.length != 0) {
      lastSrc = lastMove[0];
      lastCnt = lastMove[1];
      lastDst = lastMove[2];
    }
    for (var dst = 0; dst < fields.length; ++dst) {
      var dstHeight = fields[dst].length;
      if (dstHeight === 0) {
        if (piecesLeft[nextPlayer]) {
          moves.push([-1, 1, dst]);
        }
      } else {
        var options = moveTemplates[dst][dstHeight];
        for (var i = 0; i < options.length; ++i) {
          var src = options[i][0];
          var srcHeight = fields[src].length;
          if (srcHeight !== 0 && (occupied & options[i][1]) === 0) {
            for (var cnt = 1; cnt <= srcHeight; ++cnt) {
              if (src == lastDst && cnt === lastCnt && dst == lastSrc) continue;
              moves.push([src, cnt, dst]);
            }
          }
        }
      }
    }
    if (moves.length === 0) moves.push(PASS);
    return moves;
  }
  function getMoveWinner(move) {
    if (move.length !== 0 && fields[move[2]].length + move[1] >= cfg2.winningHeight) {
      var srcField = fields[move[0]];
      return srcField[srcField.length - 1];
    }
    return -1;
  }
  function triageMoves(moves) {
    var winningMoves = [];
    var neutralMoves = [];
    var losingMoves = [];
    for (var i = 0; i < moves.length; ++i) {
      var move = moves[i];
      var winner = getMoveWinner(move);
      if (winner === -1) {
        neutralMoves.push(move);
      } else if (winner === nextPlayer) {
        winningMoves.push(move);
      } else {
        losingMoves.push(move);
      }
    }
    return [winningMoves, neutralMoves, losingMoves];
  }
  function playRandomMove() {
    var triagedMoves = triageMoves(generateMoves());
    for (var i = 0; i < triagedMoves.length; ++i) {
      var moves = triagedMoves[i];
      if (moves.length > 0) {
        doMove(randomChoice(moves));
        return;
      }
    }
    throw new Error("No moves available!");
  }
  function randomPlayout(maxSteps) {
    for (var step = 0; step < maxSteps; ++step) {
      if (getWinner() !== -1) return step;
      playRandomMove();
    }
    return maxSteps;
  }
  function debugPrint() {
    log("Scores left: " + scoresLeft);
    log("Pieces left: " + piecesLeft);
    log("Player " + (nextPlayer + 1) + " to move.");
    for (var r = 0; r < cfg2.rows; ++r) {
      var line = formatRow(r) + "  ";
      for (var c = 0; c < cfg2.cols; ++c) {
        var src = rowColToFieldIndex(cfg2, r, c);
        var part = "";
        if (src === -1) {
          part = "#";
        } else if (fields[src].length === 0) {
          part = ".";
        } else {
          for (var i = 0; i < fields[src].length; ++i) {
            part += String(fields[src][i] + 1);
          }
        }
        while (part.length < cfg2.winningHeight) part += " ";
        line += " " + part;
        if (src !== -1 && (occupied & 1 << src) !== 0 != (fields[src].length !== 0)) {
          log("INTERNAL ERROR: occupied does not match fields at " + src);
        }
      }
      log(line);
    }
    var line = "   ";
    for (var c = 0; c < cfg2.cols; ++c) {
      var part = formatCol(c);
      while (part.length < cfg2.winningHeight) part += " ";
      line += " " + part;
    }
    log(line);
    log("last move: " + (lastMove ? formatMove(cfg2, lastMove) : "none"));
    var moves = generateMoves();
    log(moves.length + " possible moves: " + formatMoves(cfg2, moves));
  }
  function toJson() {
    return {
      fields: fields,
      nextPlayer: nextPlayer,
      lastMove: lastMove,
      scoresLeft: scoresLeft,
      piecesLeft: piecesLeft
    };
  }
  function clone(winningScore) {
    return State(
      cfg2,
      cloneFields(fields),
      nextPlayer,
      lastMove,
      cloneArray(piecesLeft),
      winningScore == null ? cloneArray(scoresLeft) : arrayOfValues(cfg2.playerCount, winningScore),
      occupied
    );
  }
  return {
    getNextPlayer: getNextPlayer,
    getWinner: getWinner,
    generateMoves: generateMoves,
    doMove: doMove,
    undoMove: undoMove,
    evaluate: evaluate,
    triageMoves: triageMoves,
    randomPlayout: randomPlayout,
    debugPrint: debugPrint,
    toJson: toJson,
    clone: clone
  };
}
function createStateFromJson(cfg2, inputJson) {
  var fields = inputJson.fields;
  var occupied = 0;
  for (var i = 0; i < fields.length; ++i) {
    if (fields[i].length > 0) occupied |= 1 << i;
  }
  return State(cfg2, fields, inputJson.nextPlayer, inputJson.lastMove, inputJson.piecesLeft, inputJson.scoresLeft, occupied);
}

// src/cpu-player.js
function convertMoveFromApi(cfg2, apiMove) {
  if (apiMove == null) return null;
  if (apiMove.length === 0) return apiMove;
  var src = apiMove[0];
  var cnt = apiMove[1];
  var dst = apiMove[2];
  if (src !== -1) src = cfg2.apiToFieldIndex[src];
  dst = cfg2.apiToFieldIndex[dst];
  return [src, cnt, dst];
}
function initCpuWrapper(jsonBoard) {
  return createConfig(
    game.getBoardDimensionY(),
    game.getBoardDimensionX(),
    JSON.parse(jsonBoard),
    game.getOutside(),
    game.getPadding(),
    game.getHeightToWin(),
    // padding size
    game.getHeightToWin(),
    game.getNumOfPlayers()
  );
}
function callCpuWrapper(findBestMoves2, cfg2, jsonBoard) {
  var board = JSON.parse(jsonBoard);
  var nextPlayer = game.getID() - 1;
  if (!Number.isInteger(nextPlayer) || nextPlayer < 0 || nextPlayer >= cfg2.playerCount) {
    throw new Error("Invalid player ID");
  }
  var apiMoves = JSON.parse(game.getLegalMoves());
  if (apiMoves.length === 0) throw new Error("No moves available");
  if (apiMoves.length === 1) return apiMoves[0];
  var moves = apiMoves.map(convertMoveFromApi.bind(null, cfg2));
  var fields = [];
  for (var i = 0; i < cfg2.fieldCount; ++i) {
    var field = [];
    var string = board[cfg2.fieldIndexToApi[i]];
    for (var j = 0; j < string.length; ++j) {
      var piece = string.charCodeAt(j) - "1".charCodeAt(0);
      if (piece < 0 || piece >= cfg2.playerCount) throw new Error("Invalid piece");
      field.push(piece);
    }
    fields.push(field);
  }
  if (fields.length !== cfg2.fieldCount) throw new Error("Invalid number of fields");
  var state = createStateFromJson(cfg2, {
    fields: fields,
    nextPlayer: nextPlayer,
    piecesLeft: game.getNumberOfStones(),
    scoresLeft: game.getTowersNeededToWin(),
    lastMove: convertMoveFromApi(game.getLastMove())
  });
  var result = findBestMoves2(cfg2, state, moves);
  var bestMoves = result[0];
  var bestValue = result[1];
  var bestMove = randomChoice(bestMoves);
  log(moves.length + " moves, " + bestMoves.length + " best with value " + bestValue + ": " + formatMoves(cfg2, bestMoves) + "; selected " + formatMove(cfg2, bestMove) + " at random");
  var moveIndex = indexOfMove(moves, bestMove);
  if (moveIndex < 0) throw new Error("Best move not found somehow?!");
  return apiMoves[moveIndex];
}

// src/MinimaxCPU.js
var cfg = null;
function initCPU(jsonBoard) {
  if (game.getNumOfPlayers() !== 2) {
    throw new Error("Unsupported number of players!");
  }
  cfg = initCpuWrapper(jsonBoard);
}
function callCPU(jsonBoard) {
  if (cfg == null) throw new Error("initCPU() has not been called!");
  return callCpuWrapper(findBestMoves, cfg, jsonBoard);
}

MonteCarloCPU.js

/**
 * \file MonteCarloCPU.js
 *
 * \section LICENSE
 *
 * Copyright (C) 2024 Maks Verver
 *
 * This file is part of StackAndConquer.
 *
 * StackAndConquer is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * StackAndConquer is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with StackAndConquer.  If not, see <https://www.gnu.org/licenses/>.
 *
 * \section DESCRIPTION
 *
 * CPU opponent using Monte Carlo simulations.
 *
 * This file was auto-generated from multiple source files. The original source
 * code is available here: https://github.com/maksverver/stackandconquer-ai/
 */

'use strict';

// src/util.js
var log = typeof game === "object" ? game.log : console.log;
function createConfig(rows, cols, inputFields, outside, padding, paddingSize, winningHeight, playerCount) {
  var paddedRows = rows + 2 * paddingSize;
  var paddedCols = cols + 2 * paddingSize;
  if (inputFields.length !== paddedRows * paddedCols) {
    throw new Error("Invalid length of input fields");
  }
  var apiToFieldIndex = [];
  var fieldIndexToApi = [];
  var fieldCount = 0;
  for (var r1 = 0; r1 < paddedRows; ++r1) {
    for (var c1 = 0; c1 < paddedCols; ++c1) {
      var i = paddedCols * r1 + c1;
      if (inputFields[i] === outside || inputFields[i] === padding) {
        apiToFieldIndex.push(-1);
      } else {
        apiToFieldIndex.push(fieldCount++);
        fieldIndexToApi.push(i);
      }
    }
  }
  if (fieldCount > 30) {
    throw new Error("Too many fields (maximum supported: 30)");
  }
  var moves = [];
  var DR = [-1, -1, -1, 0, 0, 1, 1, 1];
  var DC = [-1, 0, 1, -1, 1, -1, 0, 1];
  for (var r2 = 0; r2 < paddedRows; ++r2) {
    for (var c2 = 0; c2 < paddedCols; ++c2) {
      var j = paddedCols * r2 + c2;
      if (inputFields[j] === outside || inputFields[j] === padding) continue;
      var dst = moves.length;
      moves.push([]);
      for (var height = 0; height < winningHeight; ++height) {
        moves[dst].push([]);
      }
      for (var dir = 0; dir < 8; ++dir) {
        var dr = DR[dir], dc = DC[dir];
        var mask = 0;
        for (var height = 1; height < winningHeight; ++height) {
          var r1 = r2 - dr * height;
          var c1 = c2 - dc * height;
          if (r1 < 0 || r1 >= paddedRows || c1 < 0 || c1 >= paddedCols) break;
          var i = paddedCols * r1 + c1;
          if (inputFields[i] === outside || inputFields[i] === padding) break;
          var src = apiToFieldIndex[i];
          moves[dst][height].push([src, mask]);
          mask |= 1 << src;
        }
      }
    }
  }
  return Object.freeze({
    apiToFieldIndex: Object.freeze(apiToFieldIndex),
    fieldIndexToApi: Object.freeze(fieldIndexToApi),
    fieldCount: fieldCount,
    moves: Object.freeze(moves),
    winningHeight: winningHeight,
    playerCount: playerCount,
    // These are only used for move parsing/formatting and debug printing:
    rows: rows,
    cols: cols,
    paddingSize: paddingSize
  });
}
function fieldIndexToRowCol(cfg2, index) {
  var i = cfg2.fieldIndexToApi[index];
  var pad = cfg2.paddingSize;
  var rowStride = pad * 2 + cfg2.cols;
  var col = i % rowStride;
  var row = (i - col) / rowStride;
  return [row - pad, col - pad];
}
function rowColToFieldIndex(cfg2, row, col) {
  var pad = cfg2.paddingSize;
  var rowStride = pad * 2 + cfg2.cols;
  var res = cfg2.apiToFieldIndex[rowStride * (row + pad) + (col + pad)];
  return res == null ? -1 : res;
}
function arrayOfValues(len, value) {
  var res = [];
  for (var i = 0; i < len; ++i) res.push(value);
  return res;
}
function arrayEquals(a, b) {
  if (a.length !== b.length) return false;
  for (var i = 0; i < a.length; ++i) if (a[i] !== b[i]) return false;
  return true;
}
function indexOfMove(moves, move) {
  for (var i = 0; i < moves.length; ++i) {
    if (arrayEquals(move, moves[i])) return i;
  }
  return -1;
}
function randomChoice(array) {
  return array[Math.floor(Math.random() * array.length)];
}

// src/montecarlo.js
var TOTAL_SIMULATIONS = 4e3;
var MIN_SIMULATIONS_PER_MOVE = 10;
var MAX_STEPS_TO_SIMULATE = 250;
function evaluateWithRandomPlayouts(player, initialState, simulations) {
  var value = 0;
  var errorPrinted = false;
  for (var n = 0; n < simulations; ++n) {
    var state = initialState.clone(1);
    var steps = state.randomPlayout(MAX_STEPS_TO_SIMULATE);
    if (steps >= MAX_STEPS_TO_SIMULATE && !errorPrinted) {
      log("WARNING: maxSteps exceeded!");
      errorPrinted = true;
    }
    var winner = state.getWinner();
    value += winner === player ? 1 : winner === -1 ? 0.5 : 0;
  }
  return value / simulations;
}
function findBestMoves(cfg2, state, moves) {
  var triagedMoves = state.triageMoves(moves);
  if (triagedMoves[0].length > 0) {
    return [triagedMoves[0], 1];
  }
  var neutralMoves = triagedMoves[1];
  if (neutralMoves.length === 0) {
    return [triagedMoves[2], 0];
  }
  var player = state.getNextPlayer();
  var simulationsPerMove = Math.max(MIN_SIMULATIONS_PER_MOVE, Math.floor(TOTAL_SIMULATIONS / neutralMoves.length));
  var bestMoves = [];
  var bestValue = 0;
  for (var i = 0; i < neutralMoves.length; ++i) {
    var move = neutralMoves[i];
    var undoState = state.doMove(move);
    var value = evaluateWithRandomPlayouts(player, state, simulationsPerMove);
    state.undoMove(move, undoState);
    if (value > bestValue) {
      bestValue = value;
      bestMoves.length = 0;
    }
    if (value === bestValue) {
      bestMoves.push(move);
    }
  }
  return [bestMoves, bestValue];
}

// src/formatting.js
function formatRow(row) {
  return String(row + 1);
}
function formatCol(col) {
  return String.fromCharCode("a".charCodeAt(0) + col);
}
function formatField(cfg2, field) {
  var coords = fieldIndexToRowCol(cfg2, field);
  return formatCol(coords[1]) + formatRow(coords[0]);
}
function formatMove(cfg2, move) {
  if (move.length === 0) return "pass";
  var src = move[0];
  var cnt = move[1];
  var dst = move[2];
  var res = "";
  if (cnt !== 1) res += String(cnt);
  if (src !== -1) res += formatField(cfg2, src);
  res += formatField(cfg2, dst);
  return res;
}
function formatMoves(cfg2, moves) {
  var res = "";
  for (var i = 0; i < moves.length; ++i) {
    if (i > 0) res += " ";
    res += formatMove(cfg2, moves[i]);
  }
  return res;
}

// src/State.js
var PASS = Object.freeze([]);
function cloneArray(arr) {
  return arr.slice();
}
function cloneFields(arr) {
  return arr.map(cloneArray);
}
function State(cfg2, fields, nextPlayer, lastMove, piecesLeft, scoresLeft, occupied) {
  function getNextPlayer() {
    return nextPlayer;
  }
  function getWinner() {
    return scoresLeft.indexOf(0);
  }
  function doMoveInternal(move) {
    var removed = null;
    if (move.length !== 0) {
      var src = move[0];
      var cnt = move[1];
      var dst = move[2];
      var dstField = fields[dst];
      if (src === -1) {
        --piecesLeft[nextPlayer];
        dstField.push(nextPlayer);
        occupied ^= 1 << dst;
      } else {
        var srcField = fields[src];
        dstField.push.apply(dstField, srcField.splice(srcField.length - cnt));
        if (srcField.length === 0) {
          occupied ^= 1 << src;
        }
        if (dstField.length >= cfg2.winningHeight) {
          removed = dstField.splice(0);
          var winner = removed[removed.length - 1];
          scoresLeft[winner] -= 1;
          occupied ^= 1 << dst;
          for (var i = 0; i < removed.length; ++i) ++piecesLeft[removed[i]];
        }
      }
      ++nextPlayer;
      if (nextPlayer === cfg2.playerCount) nextPlayer = 0;
      lastMove = move;
      return removed;
    }
  }
  function doMove(move) {
    return [lastMove, doMoveInternal(move)];
  }
  function undoMove(move, undoState) {
    if (nextPlayer === 0) nextPlayer = cfg2.playerCount;
    --nextPlayer;
    lastMove = undoState[0];
    if (move.length !== 0) {
      var src = move[0];
      var cnt = move[1];
      var dst = move[2];
      var dstField = fields[dst];
      if (src === -1) {
        ++piecesLeft[nextPlayer];
        dstField.pop();
        occupied ^= 1 << dst;
      } else {
        var srcField = fields[src];
        var removed = undoState[1];
        if (removed != null) {
          for (var i = 0; i < removed.length; ++i) --piecesLeft[removed[i]];
          var winner = removed[removed.length - 1];
          scoresLeft[winner] += 1;
          dstField.push.apply(dstField, removed);
          occupied ^= 1 << dst;
        }
        if (srcField.length === 0) {
          occupied ^= 1 << src;
        }
        srcField.push.apply(srcField, dstField.splice(dstField.length - cnt));
      }
    }
  }
  function evaluate() {
    var winner = getWinner();
    if (winner !== -1) return winner === nextPlayer ? 1e9 : -1e9;
    var score = 1e4 * (scoresLeft[1 - nextPlayer] - scoresLeft[nextPlayer]);
    for (var dst = 0; dst < fields.length; ++dst) {
      var dstField = fields[dst];
      var dstHeight = dstField.length;
      if (dstHeight > 0) {
        var options = cfg2.moves[dst][dstHeight];
        for (var i = 0; i < options.length; ++i) {
          var src = options[i][0];
          var srcField = fields[src];
          var srcHeight = srcField.length;
          if (srcHeight + dstHeight >= cfg2.winningHeight && (occupied & options[i][1]) === 0) {
            if (srcField[srcHeight - 1] === nextPlayer) {
              score += 1e3;
            } else {
              score -= 100;
            }
          }
        }
        if (dstField[dstHeight - 1] === nextPlayer) {
          score += 10 * dstHeight;
        } else {
          score -= 10 * dstHeight;
        }
        for (var i = 0; i < dstHeight; ++i) {
          if (dstField[i] === nextPlayer) {
            score += 1 + i;
          } else {
            score -= 1 + i;
          }
        }
      }
    }
    return score;
  }
  function generateMoves() {
    if (getWinner() !== -1) return [];
    var moveTemplates = cfg2.moves;
    var moves = [];
    var lastSrc = -1, lastCnt = 0, lastDst = -1;
    if (lastMove != null && lastMove.length != 0) {
      lastSrc = lastMove[0];
      lastCnt = lastMove[1];
      lastDst = lastMove[2];
    }
    for (var dst = 0; dst < fields.length; ++dst) {
      var dstHeight = fields[dst].length;
      if (dstHeight === 0) {
        if (piecesLeft[nextPlayer]) {
          moves.push([-1, 1, dst]);
        }
      } else {
        var options = moveTemplates[dst][dstHeight];
        for (var i = 0; i < options.length; ++i) {
          var src = options[i][0];
          var srcHeight = fields[src].length;
          if (srcHeight !== 0 && (occupied & options[i][1]) === 0) {
            for (var cnt = 1; cnt <= srcHeight; ++cnt) {
              if (src == lastDst && cnt === lastCnt && dst == lastSrc) continue;
              moves.push([src, cnt, dst]);
            }
          }
        }
      }
    }
    if (moves.length === 0) moves.push(PASS);
    return moves;
  }
  function getMoveWinner(move) {
    if (move.length !== 0 && fields[move[2]].length + move[1] >= cfg2.winningHeight) {
      var srcField = fields[move[0]];
      return srcField[srcField.length - 1];
    }
    return -1;
  }
  function triageMoves(moves) {
    var winningMoves = [];
    var neutralMoves = [];
    var losingMoves = [];
    for (var i = 0; i < moves.length; ++i) {
      var move = moves[i];
      var winner = getMoveWinner(move);
      if (winner === -1) {
        neutralMoves.push(move);
      } else if (winner === nextPlayer) {
        winningMoves.push(move);
      } else {
        losingMoves.push(move);
      }
    }
    return [winningMoves, neutralMoves, losingMoves];
  }
  function playRandomMove() {
    var triagedMoves = triageMoves(generateMoves());
    for (var i = 0; i < triagedMoves.length; ++i) {
      var moves = triagedMoves[i];
      if (moves.length > 0) {
        doMove(randomChoice(moves));
        return;
      }
    }
    throw new Error("No moves available!");
  }
  function randomPlayout(maxSteps) {
    for (var step = 0; step < maxSteps; ++step) {
      if (getWinner() !== -1) return step;
      playRandomMove();
    }
    return maxSteps;
  }
  function debugPrint() {
    log("Scores left: " + scoresLeft);
    log("Pieces left: " + piecesLeft);
    log("Player " + (nextPlayer + 1) + " to move.");
    for (var r = 0; r < cfg2.rows; ++r) {
      var line = formatRow(r) + "  ";
      for (var c = 0; c < cfg2.cols; ++c) {
        var src = rowColToFieldIndex(cfg2, r, c);
        var part = "";
        if (src === -1) {
          part = "#";
        } else if (fields[src].length === 0) {
          part = ".";
        } else {
          for (var i = 0; i < fields[src].length; ++i) {
            part += String(fields[src][i] + 1);
          }
        }
        while (part.length < cfg2.winningHeight) part += " ";
        line += " " + part;
        if (src !== -1 && (occupied & 1 << src) !== 0 != (fields[src].length !== 0)) {
          log("INTERNAL ERROR: occupied does not match fields at " + src);
        }
      }
      log(line);
    }
    var line = "   ";
    for (var c = 0; c < cfg2.cols; ++c) {
      var part = formatCol(c);
      while (part.length < cfg2.winningHeight) part += " ";
      line += " " + part;
    }
    log(line);
    log("last move: " + (lastMove ? formatMove(cfg2, lastMove) : "none"));
    var moves = generateMoves();
    log(moves.length + " possible moves: " + formatMoves(cfg2, moves));
  }
  function toJson() {
    return {
      fields: fields,
      nextPlayer: nextPlayer,
      lastMove: lastMove,
      scoresLeft: scoresLeft,
      piecesLeft: piecesLeft
    };
  }
  function clone(winningScore) {
    return State(
      cfg2,
      cloneFields(fields),
      nextPlayer,
      lastMove,
      cloneArray(piecesLeft),
      winningScore == null ? cloneArray(scoresLeft) : arrayOfValues(cfg2.playerCount, winningScore),
      occupied
    );
  }
  return {
    getNextPlayer: getNextPlayer,
    getWinner: getWinner,
    generateMoves: generateMoves,
    doMove: doMove,
    undoMove: undoMove,
    evaluate: evaluate,
    triageMoves: triageMoves,
    randomPlayout: randomPlayout,
    debugPrint: debugPrint,
    toJson: toJson,
    clone: clone
  };
}
function createStateFromJson(cfg2, inputJson) {
  var fields = inputJson.fields;
  var occupied = 0;
  for (var i = 0; i < fields.length; ++i) {
    if (fields[i].length > 0) occupied |= 1 << i;
  }
  return State(cfg2, fields, inputJson.nextPlayer, inputJson.lastMove, inputJson.piecesLeft, inputJson.scoresLeft, occupied);
}

// src/cpu-player.js
function convertMoveFromApi(cfg2, apiMove) {
  if (apiMove == null) return null;
  if (apiMove.length === 0) return apiMove;
  var src = apiMove[0];
  var cnt = apiMove[1];
  var dst = apiMove[2];
  if (src !== -1) src = cfg2.apiToFieldIndex[src];
  dst = cfg2.apiToFieldIndex[dst];
  return [src, cnt, dst];
}
function initCpuWrapper(jsonBoard) {
  return createConfig(
    game.getBoardDimensionY(),
    game.getBoardDimensionX(),
    JSON.parse(jsonBoard),
    game.getOutside(),
    game.getPadding(),
    game.getHeightToWin(),
    // padding size
    game.getHeightToWin(),
    game.getNumOfPlayers()
  );
}
function callCpuWrapper(findBestMoves2, cfg2, jsonBoard) {
  var board = JSON.parse(jsonBoard);
  var nextPlayer = game.getID() - 1;
  if (!Number.isInteger(nextPlayer) || nextPlayer < 0 || nextPlayer >= cfg2.playerCount) {
    throw new Error("Invalid player ID");
  }
  var apiMoves = JSON.parse(game.getLegalMoves());
  if (apiMoves.length === 0) throw new Error("No moves available");
  if (apiMoves.length === 1) return apiMoves[0];
  var moves = apiMoves.map(convertMoveFromApi.bind(null, cfg2));
  var fields = [];
  for (var i = 0; i < cfg2.fieldCount; ++i) {
    var field = [];
    var string = board[cfg2.fieldIndexToApi[i]];
    for (var j = 0; j < string.length; ++j) {
      var piece = string.charCodeAt(j) - "1".charCodeAt(0);
      if (piece < 0 || piece >= cfg2.playerCount) throw new Error("Invalid piece");
      field.push(piece);
    }
    fields.push(field);
  }
  if (fields.length !== cfg2.fieldCount) throw new Error("Invalid number of fields");
  var state = createStateFromJson(cfg2, {
    fields: fields,
    nextPlayer: nextPlayer,
    piecesLeft: game.getNumberOfStones(),
    scoresLeft: game.getTowersNeededToWin(),
    lastMove: convertMoveFromApi(game.getLastMove())
  });
  var result = findBestMoves2(cfg2, state, moves);
  var bestMoves = result[0];
  var bestValue = result[1];
  var bestMove = randomChoice(bestMoves);
  log(moves.length + " moves, " + bestMoves.length + " best with value " + bestValue + ": " + formatMoves(cfg2, bestMoves) + "; selected " + formatMove(cfg2, bestMove) + " at random");
  var moveIndex = indexOfMove(moves, bestMove);
  if (moveIndex < 0) throw new Error("Best move not found somehow?!");
  return apiMoves[moveIndex];
}

// src/MonteCarloCPU.js
var cfg = null;
function initCPU(jsonBoard) {
  cfg = initCpuWrapper(jsonBoard);
}
function callCPU(jsonBoard) {
  if (cfg == null) throw new Error("initCPU() has not been called!");
  return callCpuWrapper(findBestMoves, cfg, jsonBoard);
}