# HG changeset patch
# User Oleksandr Gavenko <gavenkoa@gmail.com>
# Date 1411714430 -10800
# Node ID cab72d83a6e60419c7b3f070ecc092486cc370f6
# Parent  2839f8227a3881c07c23fec3a0d914edbf2c4beb# Parent  bf3d47ecd0ddf3ca5fe7a49a33ce9602b1a75e89
merged

diff -r bf3d47ecd0dd -r cab72d83a6e6 2048.html
--- a/2048.html	Fri Sep 26 00:57:00 2014 +0300
+++ b/2048.html	Fri Sep 26 09:53:50 2014 +0300
@@ -504,7 +504,7 @@
         return false;
       }
       if ( ! board.move[move].call(null, tmpBrd)) {
-        ui.game.setMessage("AI move "+move+" is ivalid!");
+        ui.game.setMessage("AI move '"+move+"' is ivalid!");
         return false;
       }
       return true;
diff -r bf3d47ecd0dd -r cab72d83a6e6 README.rst
--- a/README.rst	Fri Sep 26 00:57:00 2014 +0300
+++ b/README.rst	Fri Sep 26 09:53:50 2014 +0300
@@ -28,5 +28,5 @@
 =============
 
  * http://ov3y.github.io/2048-AI/ - online JS AI.
- * http://sztupy.github.io/2048-Hard/ - online JS AI with difficulty level.
+ * http://sztupy.github.io/2048-Hard/ - online JS AI with difficulty levels.
 
diff -r bf3d47ecd0dd -r cab72d83a6e6 ai.js
--- a/ai.js	Fri Sep 26 00:57:00 2014 +0300
+++ b/ai.js	Fri Sep 26 09:53:50 2014 +0300
@@ -59,8 +59,9 @@
 ai.BlindRandom = function(brdEngine) {
     this.brdEngine = brdEngine;
 }
-ai.BlindRandom.prototype.analyse = function(brd) {
-    var origBrd = new this.brdEngine(brd);
+/** Select best direction for next step. */
+ai.BlindRandom.prototype.analyse = function(brd2d) {
+    var origBrd = new this.brdEngine(brd2d);
     while (true) {
         var rnd = Math.floor(Math.random()*4);
         if (origBrd[ai.canDirs[rnd]]())
@@ -99,8 +100,9 @@
     this.threshold3 = (this.cfg.left + this.cfg.down + this.cfg.right)/total;
 }
 ai.BlindWeightRandom.bestCfg = { left: 1, right: 16, up: 4, down: 8 };
-ai.BlindWeightRandom.prototype.analyse = function(brd) {
-    var origBrd = new this.brdEngine(brd);
+/** Select best direction for next step. */
+ai.BlindWeightRandom.prototype.analyse = function(brd2d) {
+    var origBrd = new this.brdEngine(brd2d);
     while (true) {
         var rnd = Math.random();
         if (rnd < this.threshold1)
@@ -149,8 +151,9 @@
     else
         return (dir + 1) % 4;
 }
-ai.BlindCycle.prototype.analyse = function(brd) {
-    var origBrd = new this.brdEngine(brd);
+/** Select best direction for next step. */
+ai.BlindCycle.prototype.analyse = function(brd2d) {
+    var origBrd = new this.brdEngine(brd2d);
     this.prevDir = this.prevDir || 0;
     if (!this.cfg.whilePossible)
         this.prevDir = this.nextDir(this.prevDir);
@@ -198,7 +201,7 @@
     var weight = 0;
     if (this.cfg.scoreCoef > 0)
         weight += this.cfg.scoreCoef * brd.score();
-    var max = brd.max();
+    var max = brd.maxVal();
     if (this.cfg.maxValCoef > 0)
         weight += this.cfg.maxValCoef * max;
     if (this.cfg.cornerBonus > 0 && brd.atCorner(max))
@@ -206,11 +209,12 @@
     if (this.cfg.edgeBonus > 0 && brd.atEdge(max))
         weight += this.cfg.edgeBonus;
     if (this.cfg.freeBonus > 0)
-        weight += this.cfg.freeBonus * brd.free();
+        weight += this.cfg.freeBonus * brd.freeCnt();
     return weight;
 }
-ai.OneStepAhead.prototype.analyse = function(brd) {
-    var origBrd = new this.brdEngine(brd);
+/** Select best direction for next step. */
+ai.OneStepAhead.prototype.analyse = function(brd2d) {
+    var origBrd = new this.brdEngine(brd2d);
     var nextBrd = new this.brdEngine();
     var maxWeight = -1;
     var bestDir;
@@ -260,7 +264,7 @@
     var weight = 0;
     if (this.cfg.scoreCoef > 0)
         weight += this.cfg.scoreCoef * brd.score();
-    var max = brd.max();
+    var max = brd.maxVal();
     if (this.cfg.maxValCoef > 0)
         weight += this.cfg.maxValCoef * max;
     if (this.cfg.cornerBonus > 0 && brd.atCorner(max))
@@ -268,11 +272,12 @@
     if (this.cfg.edgeBonus > 0 && brd.atEdge(max))
         weight += this.cfg.edgeBonus;
     if (this.cfg.freeBonus > 0)
-        weight += this.cfg.freeBonus * brd.free();
+        weight += this.cfg.freeBonus * brd.freeCnt();
     return weight;
 }
-ai.StaticDeepMerges.prototype.analyse = function(brd) {
-    var origBrd = new this.brdEngine(brd);
+/** Select best direction for next step. */
+ai.StaticDeepMerges.prototype.analyse = function(brd2d) {
+    var origBrd = new this.brdEngine(brd2d);
     var nextBrd = new this.brdEngine();
     var prevScore = -1, nextScore = -1;
     var maxWeight = -1;
@@ -350,7 +355,7 @@
     if (cfg.scoreCoef > 0)
         score += cfg.scoreCoef * brd.score();
     if (cfg.maxValCoef > 0 || cfg.cornerBonus > 0 || cfg.edgeBonus > 0) {
-        var max = brd.max();
+        var max = brd.maxVal();
         if (cfg.maxValCoef > 0)
             score += cfg.maxValCoef * max;
         if (cfg.cornerBonus > 0)
@@ -361,20 +366,21 @@
                 score += cfg.edgeBonus;
     }
     if (cfg.freeBonus > 0)
-        score += cfg.freeBonus * brd.free();
+        score += cfg.freeBonus * brd.freeCnt();
     return score;
 }
-ai.expectimax.prototype.analyse = function(brd) {
+/** Select best direction for next step. */
+ai.expectimax.prototype.analyse = function(brd2d) {
     this.brdCache = new ai.brdCache();
-    var origBrd = new this.brdEngine(brd);
+    var origBrd = new this.brdEngine(brd2d);
     var nextBrd = new this.brdEngine();
     var maxW = -1;
     var bestDir;
     this.cleanup();
     this.depthLimit = this.cfg.depth;
-    var free = origBrd.free();
-    if (free >= 6)
-        this.depthLimit = Math.min(this.depthLimit, 6 - free/3);
+    var freeCnt = origBrd.freeCnt();
+    if (freeCnt >= 6)
+        this.depthLimit = Math.min(this.depthLimit, 6 - freeCnt/3);
     for (var i = 0; i < ai.dirs.length; i++) {
         var dir = ai.dirs[i];
         if (origBrd[dir](nextBrd)) {
diff -r bf3d47ecd0dd -r cab72d83a6e6 board.js
--- a/board.js	Fri Sep 26 00:57:00 2014 +0300
+++ b/board.js	Fri Sep 26 09:53:50 2014 +0300
@@ -64,7 +64,7 @@
     return brd;
 }
 /** Number of free cell. */
-BoardArr.prototype.free = function() {
+BoardArr.prototype.freeCnt = function() {
     var cnt = 0;
     for (var i = 0; i < 16; i++)
         if (this.brd[i] === 0)
@@ -80,7 +80,7 @@
     }
     return score;
 }
-BoardArr.prototype.max = function() {
+BoardArr.prototype.maxVal = function() {
     var max = 0;
     for (var i = 0; i < 4; i++) {
         for (var j = 0; j < 4; j++) {
@@ -170,7 +170,7 @@
     return brd;
 }
 /** Number of free cell. */
-BoardArr2d.prototype.free = function() {
+BoardArr2d.prototype.freeCnt = function() {
     var cnt = 0;
     for (var i = 0; i < 4; i++)
         for (var j = 0; j < 4; j++)
@@ -189,7 +189,7 @@
     }
     return score;
 }
-BoardArr2d.prototype.max = function() {
+BoardArr2d.prototype.maxVal = function() {
     var max = 0;
     for (var i = 0; i < 4; i++) {
         for (var j = 0; j < 4; j++) {
@@ -883,7 +883,7 @@
     return brd;
 }
 /** Number of free cell. */
-BoardObj.prototype.free = function() {
+BoardObj.prototype.freeCnt = function() {
     var cnt = 0;
     var brd = this.brd;
     if (brd.aa === 0) cnt++; if (brd.ab === 0) cnt++; if (brd.ac === 0) cnt++; if (brd.ad === 0) cnt++;
@@ -918,7 +918,7 @@
     score += lookup[brd.dd];
     return score;
 }
-BoardObj.prototype.max = function() {
+BoardObj.prototype.maxVal = function() {
     var brd = this.brd;
     var max = brd.aa;
     max = Math.max(max, brd.ab);