# HG changeset patch
# User Oleksandr Gavenko <gavenkoa@gmail.com>
# Date 1410187390 -10800
# Node ID ab294e8db00cdd106a29d229994443dd866e8cff
# Parent  94a4201d27a391fcffd4c3f1968dd4c3a21bbf8b
Add detecting value at edge or corner, free cell count. Added AI that count
max value at edges or corner and free cell count.

diff -r 94a4201d27a3 -r ab294e8db00c 2048.html
--- a/2048.html	Mon Sep 08 02:04:16 2014 +0300
+++ b/2048.html	Mon Sep 08 17:43:10 2014 +0300
@@ -88,6 +88,7 @@
       <button id="ai-next-max-score">next max score</button>
       <button id="ai-next-max-value">next max value</button>
       <button id="ai-deep-max-score">deep max score</button>
+      <button id="ai-deep-max-score-corner">deep max score corner</button>
     </div>
   </div>
 
@@ -354,6 +355,9 @@
     document.getElementById("ai-deep-max-score").addEventListener("click", function() {
       ui.ai = new ai.deepMaxScore(ui.brdEngine);
     });
+    document.getElementById("ai-deep-max-score-corner").addEventListener("click", function() {
+      ui.ai = new ai.deepMaxScoreCorner(ui.brdEngine);
+    });
 
   </script>
   
diff -r 94a4201d27a3 -r ab294e8db00c ai.js
--- a/ai.js	Mon Sep 08 02:04:16 2014 +0300
+++ b/ai.js	Mon Sep 08 17:43:10 2014 +0300
@@ -137,3 +137,81 @@
 /* Mark that next board will be unrelated to previous, so any stored precompution can be cleared. */
 ai.deepMaxScore.prototype.cleanup = function() { }
 
+
+////////////////////////////////////////////////////////////////
+// N level deep on score value + max value prefer corner,
+// without random simulation.
+////////////////////////////////////////////////////////////////
+
+/* cfg.cornerBonus - value to add if max value at corner. */
+/* cfg.edgeBonus - value to add if max value at edge. */
+ai.deepMaxScoreCorner = function(brdEngine, cfg) {
+    this.brdEngine = brdEngine;
+    this.cfg = cfg || {};
+    this.cfg.cornerBonus = this.cfg.cornerBonus || 20000;
+    this.cfg.edgeBonus = this.cfg.edgeBonus || 100;
+    this.cfg.freeBonus = this.cfg.edgeBonus || 100;
+}
+ai.deepMaxScoreCorner.prototype.scoreCorner = function(brd) {
+    var score = brd.score();
+    var max = brd.max();
+    if (brd.atCorner(max))
+        score += this.cfg.cornerBonus;
+    else if (brd.atEdge(max))
+        score += this.cfg.edgeBonus;
+    score += brd.free() * this.cfg.freeBonus;
+    return score;
+}
+ai.deepMaxScoreCorner.prototype.scoreEdge = function(brd) {
+    var score = brd.score();
+    var max = brd.max();
+    if (brd.atEdge(max))
+        score += this.cfg.edgeBonus;
+    score += brd.free() * this.cfg.freeBonus;
+    return score;
+}
+ai.deepMaxScoreCorner.prototype.analyse = function(brd) {
+    var origBrd = new this.brdEngine(brd);
+    var nextBrd = new this.brdEngine();
+    var prevScore = -1, nextScore = -1;
+    var maxScore = -1;
+    var bestDir;
+    for (var i = 0; i < ai.dirs.length; i++) {
+        var dir = ai.dirs[i];
+        if (origBrd[dir](nextBrd)) {
+            nextScore = this.scoreCorner(nextBrd);
+            var score = this.bestScore(nextBrd);
+            // console.log("dir: %o, prevScore: %o, nextScore: %o, maxScore: %o, score: %o", dir, prevScore, nextScore, maxScore, score);
+            if (maxScore < score || (maxScore === score && prevScore < nextScore)) {
+                prevScore = nextScore;
+                maxScore = score;
+                bestDir = dir;
+            }
+        }
+    }
+    return bestDir;
+}
+ai.deepMaxScoreCorner.prototype.bestScore = function(brd, seenBrds) {
+    if (seenBrds) {
+        for (var i = 0; i < seenBrds.length; i++)
+            if (brd.equals(seenBrds[i]))
+                return 0;
+    } else {
+        seenBrds = [];
+    }
+    seenBrds.push(brd);
+    var currScore = this.scoreEdge(brd);
+    var maxScore = currScore;
+    var nextBrd = new this.brdEngine();
+    for (var i = 0; i < ai.dirs.length; i++) {
+        if (brd[ai.dirs[i]](nextBrd)) {
+            var score = this.scoreEdge(nextBrd);
+            if (score > currScore)
+                maxScore = Math.max(maxScore, this.bestScore(nextBrd, seenBrds));
+        }
+    }
+    return maxScore;
+}
+/* Mark that next board will be unrelated to previous, so any stored precompution can be cleared. */
+ai.deepMaxScoreCorner.prototype.cleanup = function() { }
+
diff -r 94a4201d27a3 -r ab294e8db00c board.js
--- a/board.js	Mon Sep 08 02:04:16 2014 +0300
+++ b/board.js	Mon Sep 08 17:43:10 2014 +0300
@@ -81,6 +81,14 @@
             brd.brd[i][j] = this.brd[i][j];
     return brd;
 }
+BoardArr2d.prototype.free = function() {
+    var cnt = 0;
+    for (var i = 0; i < 4; i++)
+        for (var j = 0; j < 4; j++)
+            if (this.brd[i][j] === 0)
+                cnt++;
+    return cnt;
+}
 BoardArr2d.prototype.score = function() {
     var score = 0;
     for (var i = 0; i < 4; i++) {
@@ -101,6 +109,27 @@
     }
     return max;
 }
+BoardArr2d.prototype.find = function(val) {
+    var xy = [];
+    for (var i = 0; i < 4; i++) {
+        for (var j = 0; j < 4; j++) {
+            if (this.brd[i][j] === val)
+            xy.push([i,j]);
+        }
+    }
+    return xy;
+}
+BoardArr2d.prototype.atEdge = function(val) {
+    var brd = this.brd;
+    return (brd[0][0] === val) || (brd[0][1] === val) || (brd[0][2] === val) || (brd[0][3] === val)
+        || (brd[1][0] === val) || (brd[1][3] === val)
+        || (brd[2][0] === val) || (brd[2][3] === val)
+        || (brd[3][0] === val) || (brd[3][1] === val) || (brd[3][2] === val) || (brd[3][3] === val);
+}
+BoardArr2d.prototype.atCorner = function(val) {
+    var brd = this.brd;
+    return (brd[0][0] === val) || (brd[0][3] === val) || (brd[3][0] === val) || (brd[3][3] === val);
+}
 
 BoardArr2d.prototype.canRight = function() {
     for (var i = 0; i < 4; i++) {