Generalize pawn movements: cleaner and smaller code

[vchess.git] / client / src / variants / Suicide.js

diff --git a/client/src/variants/Suicide.js b/client/src/variants/Suicide.js
index 4bb5d36..1304ba9 100644 (file)
--- a/client/src/variants/Suicide.js
+++ b/client/src/variants/Suicide.js
@@ -1,8 +1,8 @@
 import { ChessRules } from "@/base_rules";
 import { ArrayFun } from "@/utils/array";
-import { randInt } from "@/utils/alea";
+import { shuffle } from "@/utils/alea";
 
-export const VariantRules = class SuicideRules extends ChessRules {
+export class SuicideRules extends ChessRules {
   static get HasFlags() {
     return false;
   }
@@ -11,41 +11,12 @@ export const VariantRules = class SuicideRules extends ChessRules {
     return false;
   }
 
-  getPotentialPawnMoves([x, y]) {
-    let moves = super.getPotentialPawnMoves([x, y]);
-
-    // Complete with promotion(s) into king, if possible
-    const color = this.turn;
-    const shift = color == "w" ? -1 : 1;
-    const lastRank = color == "w" ? 0 : V.size.x - 1;
-    if (x + shift == lastRank) {
-      // Normal move
-      if (this.board[x + shift][y] == V.EMPTY)
-        moves.push(
-          this.getBasicMove([x, y], [x + shift, y], { c: color, p: V.KING })
-        );
-      // Captures
-      if (
-        y > 0 &&
-        this.canTake([x, y], [x + shift, y - 1]) &&
-        this.board[x + shift][y - 1] != V.EMPTY
-      ) {
-        moves.push(
-          this.getBasicMove([x, y], [x + shift, y - 1], { c: color, p: V.KING })
-        );
-      }
-      if (
-        y < V.size.y - 1 &&
-        this.canTake([x, y], [x + shift, y + 1]) &&
-        this.board[x + shift][y + 1] != V.EMPTY
-      ) {
-        moves.push(
-          this.getBasicMove([x, y], [x + shift, y + 1], { c: color, p: V.KING })
-        );
-      }
-    }
-
-    return moves;
+  static get PawnSpecs() {
+    return Object.assign(
+      {},
+      ChessRules.PawnSpecs,
+      { promotions: ChessRules.PawnSpecs.promotions.concat([V.KING]) }
+    );
   }
 
   // Trim all non-capturing moves (not the most efficient, but easy)
@@ -152,49 +123,18 @@ export const VariantRules = class SuicideRules extends ChessRules {
         break;
       }
 
-      let positions = ArrayFun.range(8);
-
-      // Get random squares for bishops
-      let randIndex = 2 * randInt(4);
-      let bishop1Pos = positions[randIndex];
-      // The second bishop must be on a square of different color
-      let randIndex_tmp = 2 * randInt(4) + 1;
-      let bishop2Pos = positions[randIndex_tmp];
-      // Remove chosen squares
-      positions.splice(Math.max(randIndex, randIndex_tmp), 1);
-      positions.splice(Math.min(randIndex, randIndex_tmp), 1);
-
-      // Get random squares for knights
-      randIndex = randInt(6);
-      let knight1Pos = positions[randIndex];
-      positions.splice(randIndex, 1);
-      randIndex = randInt(5);
-      let knight2Pos = positions[randIndex];
-      positions.splice(randIndex, 1);
-
-      // Get random square for queen
-      randIndex = randInt(4);
-      let queenPos = positions[randIndex];
-      positions.splice(randIndex, 1);
-
-      // Random square for king (no castle)
-      randIndex = randInt(3);
-      let kingPos = positions[randIndex];
-      positions.splice(randIndex, 1);
-
-      // Rooks positions are now fixed
-      let rook1Pos = positions[0];
-      let rook2Pos = positions[1];
-
-      // Finally put the shuffled pieces in the board array
-      pieces[c][rook1Pos] = "r";
-      pieces[c][knight1Pos] = "n";
-      pieces[c][bishop1Pos] = "b";
-      pieces[c][queenPos] = "q";
-      pieces[c][kingPos] = "k";
-      pieces[c][bishop2Pos] = "b";
-      pieces[c][knight2Pos] = "n";
-      pieces[c][rook2Pos] = "r";
+      // Get random squares for every piece, totally freely
+      let positions = shuffle(ArrayFun.range(8));
+      const composition = ['b', 'b', 'r', 'r', 'n', 'n', 'k', 'q'];
+      const rem2 = positions[0] % 2;
+      if (rem2 == positions[1] % 2) {
+        // Fix bishops (on different colors)
+        for (let i=2; i<8; i++) {
+          if (positions[i] % 2 != rem2)
+            [positions[1], positions[i]] = [positions[i], positions[1]];
+        }
+      }
+      for (let i = 0; i < 8; i++) pieces[c][positions[i]] = composition[i];
     }
     return (
       pieces["b"].join("") +