Start implementing monte carlo player

computerOpponents.js

@@ -1,11 +1,15 @@
+function copyArray(array) {
+    return JSON.parse(JSON.stringify(array));
+}
+
 class ComputerOpponent {
-    constructor(game, player, level = 'random') {
+    constructor(game, player) {
         this.game = game;
         this.player = player;
-        this.level = level;
     }
 
     makeMove() {
+        console.log('comp')
         if (game.rollDice()) {
             const possibleMoves = this.getPossibleMoves();
             if (possibleMoves.length == 0) return;
@@ -30,3 +34,54 @@ class ComputerOpponent {
         return possibleMoves;
     }
 }
+
+class MonteCarloOpponent extends ComputerOpponent {
+    RANDOM_GAMES_PER_MOVE = 20;
+    MOVES_PER_GAME = 20;
+
+    constructor(game, player) {
+        super(game, player);
+
+        this.positions = copyArray(game.tokenPositons);
+    }
+
+    makeMove() {
+        if (game.rollDice()) {
+            const possibleMoves = this.getPossibleMoves();
+            if (possibleMoves.length == 0) return;
+            if (possibleMoves.length == 1) {
+                game.moveToken(this.player, possibleMoves[0]);
+                return;
+            }
+
+            const bestMove = this.monteCarlo(possibleMoves);
+            game.moveToken(this.player, bestMove);
+        }
+    }
+
+    monteCarlo(possibleMoves) {
+        const scores = [];
+
+        for (let move of possibleMoves) {
+
+            let scoreSum = 0;
+            for (let i = 0; i < this.RANDOM_GAMES_PER_MOVE; i++) {
+                scoreSum += this.randomGame(copyArray(this.positions), move);
+            }
+
+            scores.push([scoreSum, move]);
+        }
+
+        scores.sort((a, b) => a[0] - b[0]);
+        return scores[0][1];
+    }
+
+    randomGame(positions, firstMove) {
+        let score = 0;
+
+        // TODO: implement random game simulation and scoring
+
+        return score;
+    }
+}
+

game.js

@@ -13,7 +13,7 @@ let game;
 
 class Game {
 
-    constructor(players, computerOpponentIndices = []) {
+    constructor(players, computerOpponentIndices = [], computerOpponentLevel = 'easy') {
         this.players = players;
         this.numberOfPlayers = players.length;
         this.computerOpponentIndices = computerOpponentIndices; // which of the indices of players are robots
@@ -60,7 +60,7 @@ class Game {
         // create computer components
         this.computerOpponents = {};
         for (let index of this.computerOpponentIndices) {
-            this.computerOpponents[index] = new ComputerOpponent(this, this.players[index]);
+            this.computerOpponents[index] = new (computerOpponentLevel === 'hard' ? MonteCarloOpponent : ComputerOpponent)(this, this.players[index]);
         }
     }
 
@@ -318,8 +318,9 @@ window.addEventListener('keypress', event => {
     }
 });
 
-function setPlayers(players, computerOpponentIndices) {
-    game = new Game(players, computerOpponentIndices);
+function setPlayers(players, computerOpponentIndices, computerOpponentLevel) {
+    game = new Game(players, computerOpponentIndices, computerOpponentLevel);
+
     popup.style.display = 'none';
     main.style.opacity = 1;
 
@@ -334,6 +335,7 @@ document.getElementById('3-players-button').addEventListener('click', () => setP
 document.getElementById('4-players-button').addEventListener('click', () => setPlayers(allPossiblePlayers));
 
 document.getElementById('easy-mode').addEventListener('click', () => setPlayers([allPossiblePlayers[0], allPossiblePlayers[2]], [1]));
+document.getElementById('hard-mode').addEventListener('click', () => setPlayers([allPossiblePlayers[0], allPossiblePlayers[2]], [1], 'hard'));
 
 h1.addEventListener('click', () => location.reload());
 

index.html

@@ -36,6 +36,7 @@ <h1>Ludo 3D</h1>
 
         <div class="button-row">
             <button id="easy-mode">Easy</button>
+            <button id="hard-mode">Hard</button>
         </div>
     </div>