a little refactoring

fcore/game-update.sml

@@ -1,10 +1,66 @@
 structure GameUpdate =
 struct
+  open GameType
+
+  fun getEnemyRecoilPatches (player, playerOnRight, acc) =
+    if playerOnRight then
+      let
+        val newRecoil = RECOIL_RIGHT 0
+        val newAttacked = ATTACKED 0
+      in
+        W_RECOIL newRecoil :: W_ATTACKED newAttacked :: W_FACING FACING_LEFT
+        :: W_Y_AXIS FALLING :: W_X_AXIS STAY_STILL :: acc
+      end
+    else
+      let
+        val newRecoil = RECOIL_LEFT 0
+        val newAttacked = ATTACKED 0
+      in
+        W_RECOIL newRecoil :: W_ATTACKED newAttacked :: W_FACING FACING_RIGHT
+        :: W_Y_AXIS FALLING :: W_X_AXIS STAY_STILL :: acc
+      end
+
+  fun checkEnemies (player: player, enemies: enemy vector, lst, acc) =
+    case lst of
+      id :: tl =>
+        let
+          val playerOnRight =
+            (* check if collision is closer to left side of enemy or right
+             * and then chose appropriate direction to recoil in *)
+            let
+              val {x, ...} = player
+              val pFinishX = x + Player.size
+              val pHalfW = Player.size div 2
+              val pCentreX = x + pHalfW
+
+              val {x = ex, y = ey, ...} = Vector.sub (enemies, id - 1)
+              val eFinishX = ex + Enemy.size
+              val eHalfW = Enemy.size div 2
+              val eCentreX = ex + eHalfW
+            in
+              eCentreX < pCentreX
+            end
+
+          val acc = getEnemyRecoilPatches (player, playerOnRight, acc)
+        in
+          checkEnemies (player, enemies, tl, acc)
+        end
+    | [] => acc
+
+  fun checkEnemiesWhileAttacking (player, enemies, lst, acc) =
+    let
+      open QuadTree
+    in
+      case lst of
+        enemyID :: tl => (* placeholder *) acc
+      | [] => acc
+    end
+
   fun update (game, input) =
     let
       val {player, walls, wallTree, platforms, platformTree, enemies, enemyTree} =
         game
-      val player = Player.move (game, input)
+      val player = Player.runPhysicsAndInput (game, input)
     in
       { player = player
       , walls = walls