Open Loop: now we can compute bestCommands

xpmatteo · Nov 14, 2023 · c938c44 · c938c44
1 parent dce6933
commit c938c44
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Showing 2 changed files with 41 additions and 15 deletions.
diff --git a/src/ai/OpenLoopNode.js b/src/ai/OpenLoopNode.js
@@ -72,10 +72,45 @@ export default class OpenLoopNode {
     }
 
     /**
+        This decides which is the best command for the real game
+       @returns {[Command, OpenLoopNode]}
+    */
+    bestAbsoluteChild() {
+        if (this.childrenSize === 0) {
+            throw new Error("No children???");
+        }
+        let best = undefined;
+        let bestValue = -Infinity;
+        for (let [__, [command, child]] of this.#children) {
+            if (child.value() > bestValue) {
+                best = [command, child];
+                bestValue = child.value();
+            }
+        }
+        return best;
+    }
+
+    /**
+     * Returns the best commands sequence for the real game, stopping after the first non-deterministic command,
+     * and before the game changes side
+     * @param {Side?} side
      * @returns {Command[]}
      */
-    bestCommands() {
-        return undefined;
+    bestCommands(side= undefined) {
+        if (side && this.side !== side) {
+            // stop because *after* this command, the side will change
+            return [];
+        }
+        if (this.childrenSize === 0) {
+            return [];
+        }
+        const [bestCommand, bestChild] = this.bestAbsoluteChild();
+        if (!bestCommand.isDeterministic()) {
+            // stop because *after* this command, we don't know what the actual situation will be
+            return [bestCommand];
+        } else {
+            return [bestCommand].concat(bestChild.bestCommands(side));
+        }
     }
 
     /**
@@ -100,5 +135,4 @@ export default class OpenLoopNode {
         }
         return this.#children.get(command.toString())[1];
     }
-
 }
diff --git a/src/ai/OpenLoopNode.test.js b/src/ai/OpenLoopNode.test.js
@@ -101,12 +101,6 @@ describe('Open Loop nodes', () => {
     });
 
     describe('bestCommands', () => {
-        function gameWithSide(side) {
-            return {
-                currentSide: side,
-            };
-        }
-
         function aDeterministicCommand(name) {
             return {
                 isDeterministic: () => true,
@@ -125,9 +119,7 @@ describe('Open Loop nodes', () => {
             return commands.map(c => c.toString());
         }
 
-        let game = gameWithSide('A');
-
-        xit('should return the best commands sequence from root to leaf', () => {
+        it('should return the best commands sequence from root to leaf', () => {
             const rootNode = new OpenLoopNode(Side.ROMAN, null, 1, 1);
             const child1 = new OpenLoopNode(Side.ROMAN, rootNode, 3, 1);
             const child2 = new OpenLoopNode(Side.ROMAN, rootNode, 4, 1);
@@ -144,7 +136,7 @@ describe('Open Loop nodes', () => {
             expect(names(result)).toEqual(['child2Command', 'grandChildCommand']);
         });
 
-        xit('should stop at the command that will switch side', () => {
+        it('should stop at the command that will switch side', () => {
             const rootNode = new OpenLoopNode(Side.ROMAN);
 
             const child1 = new OpenLoopNode(Side.CARTHAGINIAN, rootNode, 3, 1);
@@ -160,7 +152,7 @@ describe('Open Loop nodes', () => {
             expect(names(result)).toEqual(['child1Command']);
         });
 
-        xit('should stop after the first command that is not deterministic', () => {
+        it('should stop after the first command that is not deterministic', () => {
             const rootNode = new OpenLoopNode(Side.ROMAN);
 
             const child1 = new OpenLoopNode(Side.ROMAN, rootNode, 3, 1);
@@ -173,7 +165,7 @@ describe('Open Loop nodes', () => {
             child1.addChild(grandChildCommand, grandChild);
 
             const result = rootNode.bestCommands(Side.ROMAN);
-            expect(names(result)).toEqual(['rootCommand', 'child1Command']);
+            expect(names(result)).toEqual(['child1Command']);
         });
     });