Don't allow automatic room creation

app.py

@@ -206,20 +206,47 @@ async def favicon_update_s(request):
     return HTTPResponse(request, favicon_update, content_type="image/x-icon")
 
 
+letters = string.ascii_lowercase + string.digits
+
+
+def room_key():
+    key: str = "".join(random.choices(letters, k=4))
+    while key in rooms.keys():
+        key: str = "".join(random.choices(letters, k=4))
+    return key
+
+
+@app.POST("/create_room")
+async def new_room(request):
+    if len(rooms) == len(letters) ** 4:
+        return HTTPResponse(request, "Out of service", status=501)
+    key = room_key()
+    rooms[key] = Room()
+    return JSONResponse(
+        request,
+        {
+            "id": key,
+        },
+    )
+
 @app.GET("/")
 async def home(request):
-    return render(request, "index.html")
+    return render(request, "home.html")
 
 
 @app.GET("/<id>")
-async def home_with_id(request, id):
+async def game(request, id):
-    return render(request, "index.html")
+    if not re.match(r"[a-z0-9]{4}", id):
+        return redirect("/")
+    if id not in rooms:
+        return redirect("/")
+    return render(request, "game.html")
 
 
 @app.POST("/join/<room_id>")
 async def join(request, room_id):
     if room_id not in rooms:
-        rooms[room_id] = Room()
+        return JSONResponse(request, {"code": "NOGO", "error": "Room not found."}, 404)
     room: Room = rooms[room_id]
     player = room.add_player()
     if player: