IPVGO: Nerf overly-difficult handicap, [issue #1169] misc bugfixes (#1188)

* IPVGO: Nerf overly-difficult handicap on 5x5 board

* IPVGO: Tweak 5x5 handicap

src/Go/boardState/boardState.ts

@@ -24,6 +24,7 @@ export function getNewBoardState(
   if (ai === GoOpponent.w0r1d_d43m0n) {
     boardToCopy = resetCoordinates(rotate90Degrees(boardFromSimpleBoard(bitverseBoardShape)));
     boardSize = 19;
+    applyObstacles = false;
   }
 
   const newBoardState: BoardState = {
@@ -64,7 +65,13 @@ export function getNewBoardState(
 export function getHandicap(boardSize: number, opponent: GoOpponent) {
   // Illuminati and WD get a few starting routers
   if (opponent === GoOpponent.Illuminati || opponent === GoOpponent.w0r1d_d43m0n) {
-    return ceil(boardSize * 0.35);
+    return {
+      [5]: 1,
+      [7]: 3,
+      [9]: 4,
+      [13]: 5,
+      [19]: 7,
+    }[boardSize];
   }
   return 0;
 }
@@ -124,6 +131,13 @@ export function applyHandicap(board: Board, handicap: number): void {
   const handicapMoveOptions = getExpansionMoveArray(board, availableMoves);
   const handicapMoves: Move[] = [];
 
+  // Special handling for 5x5: extra weight on handicap piece in the center of the board
+  if (availableMoves.length < 26 && board[2][2] && Math.random() < 0.2) {
+    board[2][2].color = GoColor.white;
+    updateChains(board);
+    return;
+  }
+
   // select random distinct moves from the move options list up to the specified handicap amount
   for (let i = 0; i < handicap && i < handicapMoveOptions.length; i++) {
     const index = floor(Math.random() * handicapMoveOptions.length);

test/jest/Go/boardState.test.ts

@@ -0,0 +1,77 @@
+import { getNewBoardState, makeMove, passTurn, updateCaptures } from "../../../src/Go/boardState/boardState";
+import { GoColor, GoOpponent } from "@enums";
+import { boardFromSimpleBoard, simpleBoardFromBoard } from "../../../src/Go/boardAnalysis/boardAnalysis";
+import { resetCoordinates, rotate90Degrees } from "../../../src/Go/boardState/offlineNodes";
+import { bitverseBoardShape } from "../../../src/Go/Constants";
+
+describe("Board analysis utility tests", () => {
+  it("Correctly applies the board size and handicap for 5x5 board", () => {
+    const result = getNewBoardState(5, GoOpponent.Illuminati, false);
+    const whitePieceCount = simpleBoardFromBoard(result.board)
+      .join("")
+      .split("")
+      .filter((p) => p === "O").length;
+    expect(whitePieceCount).toEqual(1);
+    expect(result).toEqual({
+      board: expect.any(Object),
+      previousPlayer: GoColor.white,
+      previousBoards: [],
+      ai: GoOpponent.Illuminati,
+      passCount: 0,
+      cheatCount: 0,
+    });
+  });
+
+  it("Correctly applies the board size and handicap for the special opponent", () => {
+    const result = getNewBoardState(5, GoOpponent.w0r1d_d43m0n, true);
+    const simpleBoard = simpleBoardFromBoard(result.board);
+    const whitePieceCount = simpleBoard
+      .join("")
+      .split("")
+      .filter((p) => p === "O").length;
+    // Handicap of 7
+    expect(whitePieceCount).toEqual(7);
+    // Special board: 19x19 (even if other board size is passed in)
+    expect(result.board[0]?.length).toEqual(19);
+
+    // Special board shape
+    const boardWithNoRouters = simpleBoard.map((row) =>
+      row
+        .split("")
+        .map((p) => (p === "O" ? "." : p))
+        .join(""),
+    );
+    const specialBoardTemplate = simpleBoardFromBoard(
+      resetCoordinates(rotate90Degrees(boardFromSimpleBoard(bitverseBoardShape))),
+    );
+    expect(boardWithNoRouters).toEqual(specialBoardTemplate);
+  });
+
+  it("Correctly applies moves made", () => {
+    const result = getNewBoardState(5, GoOpponent.Daedalus, false);
+    makeMove(result, 1, 1, GoColor.black);
+
+    expect(simpleBoardFromBoard(result.board)).toEqual([".....", ".X...", ".....", ".....", "....."]);
+  });
+
+  it("Correctly applies passes made", () => {
+    const result = getNewBoardState(5, GoOpponent.Daedalus, false);
+    expect(result.previousPlayer).toEqual(GoColor.white);
+    passTurn(result, GoColor.black);
+    expect(result.passCount).toEqual(1);
+    expect(result.previousPlayer).toEqual(GoColor.black);
+    passTurn(result, GoColor.white);
+    expect(result.passCount).toEqual(2);
+    expect(result.previousPlayer).toEqual(null);
+  });
+
+  it("Correctly updates captures and chains", () => {
+    const boardState = boardFromSimpleBoard(["OX...", "XX...", ".....", ".....", "....."]);
+    expect(boardState[0][0]?.color).toEqual(GoColor.white);
+
+    updateCaptures(boardState, GoColor.black, true);
+
+    expect(boardState[0][0]?.color).toEqual(GoColor.empty);
+    expect(boardState[0][1]?.chain).toEqual("0,1");
+  });
+});