From dcfaab5dc62ccd9701ff314ad4e3d40c40223d44 Mon Sep 17 00:00:00 2001
From: Benjamin Auder <benjamin.auder@somewhere>
Date: Mon, 4 Dec 2023 18:14:37 +0100
Subject: [PATCH] Some thoughts about Coregal

---
 base_rules.js             | 38 +++++++++++++++++++-------------------
 variants/Copycat/class.js |  2 ++
 variants/Coregal/class.js | 37 ++++++++++++++++++++-----------------
 3 files changed, 41 insertions(+), 36 deletions(-)

diff --git a/base_rules.js b/base_rules.js
index 6078da8..8c7d549 100644
--- a/base_rules.js
+++ b/base_rules.js
@@ -1520,12 +1520,8 @@ export default class ChessRules {
     let moves = this.getPotentialMovesOf(piece, [x, y]);
     if (piece == "p" && this.hasEnpassant && this.epSquare)
       Array.prototype.push.apply(moves, this.getEnpassantCaptures([x, y]));
-    if (
-      this.isKing(0, 0, piece) && this.hasCastle &&
-      this.castleFlags[color || this.turn].some(v => v < this.size.y)
-    ) {
+    if (this.isKing(0, 0, piece) && this.hasCastle)
       Array.prototype.push.apply(moves, this.getCastleMoves([x, y]));
-    }
     return this.postProcessPotentialMoves(moves);
   }
 
@@ -2015,8 +2011,9 @@ export default class ChessRules {
     return [];
   }
 
-  getCastleMoves([x, y], finalSquares, castleWith) {
+  getCastleMoves([x, y], finalSquares, castleWith, castleFlags) {
     const c = this.getColor(x, y);
+    castleFlags = castleFlags || this.castleFlags[c];
 
     // Castling ?
     const oppCols = this.getOppCols(c);
@@ -2030,12 +2027,12 @@ export default class ChessRules {
       castleSide < 2;
       castleSide++ //large, then small
     ) {
-      if (this.castleFlags[c][castleSide] >= this.size.y)
+      if (castleFlags[castleSide] >= this.size.y)
         continue;
       // If this code is reached, rook and king are on initial position
 
       // NOTE: in some variants this is not a rook
-      const rookPos = this.castleFlags[c][castleSide];
+      const rookPos = castleFlags[castleSide];
       const castlingPiece = this.getPiece(x, rookPos);
       if (
         this.board[x][rookPos] == "" ||
@@ -2238,11 +2235,20 @@ export default class ChessRules {
       this.board[psq.x][psq.y] = psq.c + psq.p;
   }
 
-  updateCastleFlags(move) {
+  // NOTE: arg "castleFlags" for Coregal or Twokings
+  updateCastleFlags(move, castleFlags) {
+    castleFlags = castleFlags || this.castleFlags;
+    // If flags already off, no need to re-check:
+    if (
+      Object.values(castleFlags).every(cvals =>
+        cvals.every(val => val >= this.size.y))
+    ) {
+      return;
+    }
     // Update castling flags if start or arrive from/at rook/king locations
     move.appear.concat(move.vanish).forEach(psq => {
       if (this.isKing(0, 0, psq.p))
-        this.castleFlags[psq.c] = [this.size.y, this.size.y];
+        castleFlags[psq.c] = [this.size.y, this.size.y];
       // NOTE: not "else if" because king can capture enemy rook...
       let c = "";
       if (psq.x == 0)
@@ -2250,22 +2256,16 @@ export default class ChessRules {
       else if (psq.x == this.size.x - 1)
         c = "w";
       if (c != "") {
-        const fidx = this.castleFlags[c].findIndex(f => f == psq.y);
+        const fidx = castleFlags[c].findIndex(f => f == psq.y);
         if (fidx >= 0)
-          this.castleFlags[c][fidx] = this.size.y;
+          castleFlags[c][fidx] = this.size.y;
       }
     });
   }
 
   prePlay(move) {
-    if (
-      this.hasCastle &&
-      // If flags already off, no need to re-check:
-      Object.values(this.castleFlags).some(cvals =>
-        cvals.some(val => val < this.size.y))
-    ) {
+    if (this.hasCastle)
       this.updateCastleFlags(move);
-    }
     if (this.options["crazyhouse"]) {
       move.vanish.forEach(v => {
         const square = C.CoordsToSquare({x: v.x, y: v.y});
diff --git a/variants/Copycat/class.js b/variants/Copycat/class.js
index e19367c..f996be5 100644
--- a/variants/Copycat/class.js
+++ b/variants/Copycat/class.js
@@ -1,5 +1,7 @@
 import ChessRules from "/base_rules.js";
 
+// TODO: there was an issue: I forgot which.. TOFIND and TOFIX :)
+
 export default class CopycatRules extends ChessRules {
 
   static get Options() {
diff --git a/variants/Coregal/class.js b/variants/Coregal/class.js
index b563fec..4df32ad 100644
--- a/variants/Coregal/class.js
+++ b/variants/Coregal/class.js
@@ -4,8 +4,6 @@ import { randInt, sample } from "@/utils/alea";
 
 export class CoregalRules extends ChessRules {
 
-//TODO: CSS royal queen symbol
-
   genRandInitBaseFen() {
     const s = FenUtil.setupPieces(
       ['r', 'n', 'b', 'l', 'k', 'b', 'n', 'r'],
@@ -13,28 +11,35 @@ export class CoregalRules extends ChessRules {
         randomness: this.options["randomness"],
         between: [{p1: 'k', p2: 'r'}, {p1: 'l', p2: 'r'}],
         diffCol: ['b'],
-        flags: ['r', 'k', 'l'] //TODO: add 'k' to all 'flags' calls ??!
+        // 'k' and 'l' useful only to get relative position
+        flags: ['r', 'k', 'l']
       }
     );
     return {
       fen: s.b.join("") + "/pppppppp/8/8/8/8/PPPPPPPP/" +
            s.w.join("").toUpperCase(),
-      o: {flags: s.flags}
+      // TODO: re-arrange flags, use another init variable "relPos" (in o)
+      // (maybe after FEN parsing, easier?)
+      o: {flags: s.flags + s.flags} //second set for royal queen
     };
   }
 
   pieces() {
     let res = super.pieces();
     res['l'] = JSON.parse(JSON.stringify(res['q']));
+    // TODO: CSS royal queen symbol (with cross?)
     res['l']["class"] = "royal_queen";
     return res;
   }
 
+  // TODO: something like that indeed (+ flags to FEN)
   setFlags(fenflags) {
-    // white pieces positions, then black pieces positions
-    this.castleFlags = { w: [...Array(4)], b: [...Array(4)] };
+    this.castleFlags = {
+      'k': { 'w': [...Array(4)], b: [...Array(4)] },
+      'l': { 'w': [...Array(4)], b: [...Array(4)] }
+    };
     for (let i = 0; i < 8; i++) {
-      this.castleFlags[i < 4 ? "w" : "b"][i % 4] =
+      this.castleFlags[i < 4 ? "k" : "l"][i % 4 < 2 ? "w" : "b"] =
         parseInt(fenflags.charAt(i), 10);
     }
   }
@@ -46,22 +51,20 @@ export class CoregalRules extends ChessRules {
   }
 
   getCastleMoves([x, y]) {
+    const c = this.getColor(x, y),
+          p = this.getPiece(x, y);
     // Relative position of the selected piece: left or right ?
     // If left: small castle left, large castle right.
     // If right: usual situation.
-    const c = this.getColor(x, y);
-    const relPos = (this.castleFlags[c][1] == y ? "left" : "right");
-
     const finalSquares = [
-      relPos == "left" ? [1, 2] : [2, 3],
-      relPos == "right" ? [6, 5] : [5, 4]
+      this.relPos[c][p] == "left" ? [1, 2] : [2, 3],
+      this.relPos[c][p] == "right" ? [6, 5] : [5, 4]
     ];
-    const saveFlags = JSON.stringify(this.castleFlags[c]);
-    // Alter flags to follow base_rules semantic
-    this.castleFlags[c] = [0, 3].map(i => this.castleFlags[c][i]);
-    const moves = super.getCastleMoves([x, y], finalSquares);
-    this.castleFlags[c] = JSON.parse(saveFlags);
+    const moves =
+      super.getCastleMoves([x, y], finalSquares, null, this.castleFlags[p]);
     return moves;
   }
 
+  // TODO: updateFlags (just pass castleFlags arg)
+
 };
-- 
2.44.0