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+#+TITLE: Remote Snake API
+
+#+OPTIONS: toc:nil
+#+LATEX_HEADER: \usepackage{fullpage}
+
+* General Description
+  - All transmissions will be based on UDP
+  - All UDP packet will contain plain json data
+* Communications 
+** Initialisation
+   1. Server wait for a client
+   2. Client can send:
+      #+BEGIN_SRC json
+        {
+            "type": "new-game"
+        }
+      #+END_SRC
+   3. Server can reply:
+      #+BEGIN_SRC json
+        {
+            "type": "state",
+            "game-id": 1,
+            "game-over": false,
+            "snake": [(1,2),(1,3)],
+            "food": [(6,7)]
+        }  
+      #+END_SRC
+** Gameplay
+*** Change Direction
+    1. When client is playing a game it can ask to the server to change snake direction:
+       #+BEGIN_SRC json
+         {
+             "type": "update",
+             "direction": "left",
+         }
+       #+END_SRC
+    2. Server can reply
+       #+BEGIN_SRC json
+         {
+             "type": "state",
+             "game-id": 1,
+             "game-over": false,
+             "snake": [(0,2),(1,2)],
+             "food": [(6,7)]
+         }  
+       #+END_SRC
+*** Refresh Screen
+    1. When no key are press (the snake is simply going straigth forward). So, client can send:
+       #+BEGIN_SRC json
+         {
+             "type": "update",
+             "direction": null
+         }
+       #+END_SRC
+    2. Server can reply:
+       #+BEGIN_SRC json
+         {
+             "type": "state",
+             "game-id": 1,
+             "game-over": false,
+             "snake": [(1,2),(0,2)],
+             "food": [(6,7)]
+         }  
+       #+END_SRC
+*** End Game
+    - When game is over server will send the following state message (switch game-over to true):
+       #+BEGIN_SRC json
+         {
+             "type": "state",
+             "game-id": 1,
+             "game-over": true,
+             "snake": [(0,2),(1,2)],
+             "food": [(6,7)]
+         }  
+       #+END_SRC
+    - No reply is expected from the client and server will be in charge to free local memory
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