From 4b5fe3061829e184f9ad86a13d831eda22d95343 Mon Sep 17 00:00:00 2001
From: Benjamin Auder <benjamin.auder@somewhere>
Date: Sun, 18 Nov 2018 01:47:58 +0100
Subject: [PATCH] More robust in-check indications (ready for Antiking)

---
 TODO                                  |  7 +++----
 public/javascripts/base_rules.js      | 12 ++++++++++++
 public/javascripts/components/game.js | 15 ++++++++-------
 public/javascripts/variants/Atomic.js | 13 +++++++++++++
 sockets.js                            |  1 +
 5 files changed, 37 insertions(+), 11 deletions(-)

diff --git a/TODO b/TODO
index d4e48b00..006b9153 100644
--- a/TODO
+++ b/TODO
@@ -1,7 +1,6 @@
 Styles must be improved (full width for smartphones, selectable text for PGN...)
 Tooltip text should fade (even when mouse stay on it, especially for small screens)
-Checkered stage 2: switch button at reserve position.
+Checkered stage 2: switch button at reserve position (or on top).
 If a played disconnect right after opponent sent a move, it might be never received: secure this
-Think about non-conventional variants with 2 kings for example: undercheck highlight?
-  --> underCheck should return a vector in this case. Adapt.
-	--> incheck should be an array of squares, in general. Think AntiKing
+Mode expert: game.js, button on top (with online indicator)
+Turn indicator on top too (black or white)
diff --git a/public/javascripts/base_rules.js b/public/javascripts/base_rules.js
index 9a4ef912..b604e797 100644
--- a/public/javascripts/base_rules.js
+++ b/public/javascripts/base_rules.js
@@ -629,6 +629,7 @@ class ChessRules
 		return false;
 	}
 
+	// Is color c under check after move ?
 	underCheck(move, c)
 	{
 		this.play(move);
@@ -637,6 +638,17 @@ class ChessRules
 		return res;
 	}
 
+	// On which squares is color c under check (after move) ?
+	getCheckSquares(move, c)
+	{
+		this.play(move);
+		let res = this.isAttacked(this.kingPos[c], this.getOppCol(c))
+			? [ JSON.parse(JSON.stringify(this.kingPos[c])) ] //need to duplicate!
+			: [ ];
+		this.undo(move);
+		return res;
+	}
+
 	// Apply a move on board
 	static PlayOnBoard(board, move)
 	{
diff --git a/public/javascripts/components/game.js b/public/javascripts/components/game.js
index 125aeea1..499e473a 100644
--- a/public/javascripts/components/game.js
+++ b/public/javascripts/components/game.js
@@ -16,7 +16,7 @@ Vue.component('my-game', {
 			oppConnected: false,
 			seek: false,
 			fenStart: "",
-			incheck: false,
+			incheck: [],
 		};
 	},
 	render(h) {
@@ -24,6 +24,9 @@ Vue.component('my-game', {
 		// Precompute hints squares to facilitate rendering
 		let hintSquares = doubleArray(sizeX, sizeY, false);
 		this.possibleMoves.forEach(m => { hintSquares[m.end.x][m.end.y] = true; });
+		// Also precompute in-check squares
+		let incheckSq = doubleArray(sizeX, sizeY, false);
+		this.incheck.forEach(sq => { incheckSq[sq[0]][sq[1]] = true; });
 		let elementArray = [];
 		let square00 = document.getElementById("sq-0-0");
 		let squareWidth = !!square00
@@ -172,8 +175,6 @@ Vue.component('my-game', {
 							}
 							const lm = this.vr.lastMove;
 							const highlight = !!lm && _.isMatch(lm.end, {x:ci,y:cj});
-							const incheck = this.incheck
-								&& _.isEqual(this.vr.kingPos[this.vr.turn], [ci,cj]);
 							return h(
 								'div',
 								{
@@ -182,7 +183,7 @@ Vue.component('my-game', {
 										'light-square': !highlight && (i+j)%2==0,
 										'dark-square': !highlight && (i+j)%2==1,
 										'highlight': highlight,
-										'incheck': incheck,
+										'incheck': incheckSq[ci][cj],
 									},
 									attrs: {
 										id: this.getSquareId({x:ci,y:cj}),
@@ -499,8 +500,8 @@ Vue.component('my-game', {
 				{
 					const oppCol = this.vr.turn;
 					const lastMove = moves[moves.length-1];
-					this.vr.undo(lastMove);
-					this.incheck = this.vr.underCheck(lastMove, oppCol);
+					this.vr.undo(lastMove, "ingame");
+					this.incheck = this.vr.getCheckSquares(lastMove, oppCol);
 					this.vr.play(lastMove, "ingame");
 				}
 				delete localStorage["newgame"];
@@ -631,7 +632,7 @@ Vue.component('my-game', {
 				return;
 			}
 			const oppCol = this.vr.getOppCol(this.vr.turn);
-			this.incheck = this.vr.underCheck(move, oppCol); //is opponent in check?
+			this.incheck = this.vr.getCheckSquares(move, oppCol); //is opponent in check?
 			// Not programmatic, or animation is over
 			if (this.mode == "human" && this.vr.turn == this.mycolor)
 			{
diff --git a/public/javascripts/variants/Atomic.js b/public/javascripts/variants/Atomic.js
index b7c7504d..bf860df6 100644
--- a/public/javascripts/variants/Atomic.js
+++ b/public/javascripts/variants/Atomic.js
@@ -131,6 +131,19 @@ class AtomicRules extends ChessRules
 		return res;
 	}
 
+	getCheckSquares(move, c)
+	{
+		const saveKingPos = this.kingPos[c]; //king might explode
+		this.play(move);
+		let res = [ ];
+		if (this.kingPos[c][0] < 0)
+			res = [saveKingPos];
+		else if (this.isAttacked(this.kingPos[c], this.getOppCol(c)))
+			res = [ this.kingPos[c] ]
+		this.undo(move);
+		return res;
+	}
+
 	checkGameEnd(color)
 	{
 		const kp = this.kingPos[color];
diff --git a/sockets.js b/sockets.js
index c3190aa2..a1818e09 100644
--- a/sockets.js
+++ b/sockets.js
@@ -20,6 +20,7 @@ module.exports = function(wss) {
 
 	// TODO: when relaying to opponent, check readyState, potential setTimeout()? + send opponent (re)disconnect
 	// (resign, newgame, newmove). See https://github.com/websockets/ws/blob/master/lib/websocket.js around line 313
+	// TODO: awaiting newmove, resign, newgame :: in memory structure
 
 	wss.on("connection", (socket, req) => {
 		//const params = new URL("http://localhost" + req.url).searchParams;
-- 
2.44.0