Finish Ultima rules + a few technical fixes

[vchess.git] / public / javascripts / base_rules.js

diff --git a/public/javascripts/base_rules.js b/public/javascripts/base_rules.js
index a10a43c..63b535d 100644 (file)
--- a/public/javascripts/base_rules.js
+++ b/public/javascripts/base_rules.js
@@ -54,7 +54,6 @@ class ChessRules
        constructor(fen, moves)
        {
                this.moves = moves;
-               this.hashStates = {}; //for repetitions detection
                // Use fen string to initialize variables, flags and board
                this.board = VariantRules.GetBoard(fen);
                this.setFlags(fen);
@@ -728,16 +727,10 @@ class ChessRules
                        this.kingPos[c] = [move.start.x, move.start.y];
        }
 
-       // Store a hash of the position + flags + turn after a move is played
-       // (for repetitions detection)
-       addHashState()
+       // Hash of position+flags+turn after a move is played (to detect repetitions)
+       getHashState()
        {
-               const strToHash = this.getFen() + " " + this.turn;
-               const hash = hex_md5(strToHash);
-               if (!this.hashStates[hash])
-                       this.hashStates[hash] = 1;
-               else
-                       this.hashStates[hash]++;
+               return hex_md5(this.getFen() + " " + this.turn);
        }
 
        play(move, ingame)
@@ -756,7 +749,7 @@ class ChessRules
                VariantRules.PlayOnBoard(this.board, move);
 
                if (!!ingame)
-                       this.addHashState();
+                       move.hash = this.getHashState();
        }
 
        undo(move)
@@ -779,6 +772,20 @@ class ChessRules
        // Check for 3 repetitions (position + flags + turn)
        checkRepetition()
        {
+               if (!this.hashStates)
+                       this.hashStates = {};
+               const startIndex =
+                       Object.values(this.hashStates).reduce((a,b) => { return a+b; }, 0)
+               // Update this.hashStates with last move (or all moves if continuation)
+               // NOTE: redundant storage, but faster and moderate size
+               for (let i=startIndex; i<this.moves.length; i++)
+               {
+                       const move = this.moves[i];
+                       if (!this.hashStates[move.hash])
+                               this.hashStates[move.hash] = 1;
+                       else
+                               this.hashStates[move.hash]++;
+               }
                return Object.values(this.hashStates).some(elt => { return (elt >= 3); });
        }