adding 502 error

games/pacman502/js/ai.js

@@ -0,0 +1,23 @@
+var updateEnemies = function(modifier){
+
+  for (var i= 0; i < enemies.length; i++){
+    var enemy = enemies[i];
+    if (isCollidingBlocks(enemy,enemy.direction)){
+      changeDirection(enemy);
+
+    } else {
+      move(enemy, modifier);
+    }
+  }
+}
+
+var changeDirection = function(enemy){
+    var tol =  p(-5,0);
+    var randomDirection = randomBetween(0, 3);
+    switch(randomDirection){
+      case 0: if (!isCollidingBlocks(enemy, LEFT, tol))  enemy.direction = LEFT;break;
+      case 1: if (!isCollidingBlocks(enemy, RIGHT, tol))  enemy.direction = RIGHT;break;
+      case 2: if (!isCollidingBlocks(enemy, UP, tol))  enemy.direction = UP;break;
+      default: if (!isCollidingBlocks(enemy, DOWN, tol))  enemy.direction = DOWN;break;
+    }
+}