1 files changed, 47 insertions, 19 deletions
diff --git a/src/macroknight/systems.hy b/src/macroknight/systems.hy
index fccccd0..8c1bb9c 100644
--- a/src/macroknight/systems.hy
+++ b/src/macroknight/systems.hy
@@ -1,25 +1,53 @@
+(import utils [sub-points Direction])
+
 ;; Define systems here
 (setv GRAVITY 5)
 
 (defclass GoalHit [Exception])
 
-(defn apply-gravity [entity entities]
-  (when (not entity.fixed)
-    (.move entity #(0 GRAVITY))))
+(defn entities-by-type [entities types]
+  (gfor ent entities
+        :if (in ent.type types)
+        ent))
+
+(defmacro defsystem [name pred #* body]
+  `(defn ~name [entity entities]
+     (when ~pred
+       ~@body)))
+
+(defsystem apply-gravity
+  (not entity.fixed)
+  (.move entity #(0 GRAVITY)))
+
+(defsystem apply-collisions
+  (not entity.fixed)
+  (for [ent (gfor enti entities
+                  :if (!= enti.id entity.id)
+                  enti)]
+    (when (.colliderect entity.rect ent.rect)
+      (if (= ent.type "goal")
+          (raise (GoalHit))
+          (let [collision-rect (.clip entity.rect ent.rect)
+                move-x (get entity.total-move 0)
+                move-y (get entity.total-move 1)]
+            (when (!= move-x 0)
+              (.move entity #((* (if (> move-x 0) -1 1) collision-rect.width) 0)))
+            (when (!= move-y 0)
+              (.move entity #(0 (* (if (> move-y 0) -1 1) collision-rect.height))))))
+      (.ground entity))))
 
-(defn apply-collisions [entity entities]
-  (when (not entity.fixed)
-    (for [ent (gfor enti entities
-                    :if (!= enti.id entity.id)
-                    enti)]
-      (when (.colliderect entity.rect ent.rect)
-        (if (= ent.type "goal")
-            (raise (GoalHit))
-            (let [collision-rect (.clip entity.rect ent.rect)
-                  move-x (get entity.total-move 0)
-                  move-y (get entity.total-move 1)]
-              (when (!= move-x 0)
-                (.move entity #((* (if (> move-x 0) -1 1) collision-rect.width) 0)))
-              (when (!= move-y 0)
-                (.move entity #(0 (* (if (> move-y 0) -1 1) collision-rect.height))))))
-        (.ground entity)))))
+(defsystem run-enemies
+  (= entity.type "enemy")
+  ;; If the player is on the tile next to the enemy, attack.
+  (let [player (next (entities-by-type entities ["player"]))
+        dist (sub-points entity.pos player.pos)
+        direction (.x-from-move Direction dist)]
+    ;; If facing the player and within reach, attack)
+    (when (and (= direction entity.facing)
+               (< (get dist 1) 1) ;; Same level
+               (< (abs (get dist 0)) 2)
+               (not entity.attacking))
+      (setv entity.attacking True)
+      (print "attack")
+      )
+    ))