add level difficulty enums for later

src/helpers/difficulty.rs

@@ -0,0 +1,23 @@
+pub enum LevelDifficulty {
+    Auto,
+    Easy,
+    Normal,
+    Hard,
+    Harder,
+    Insane,
+    Demon
+}
+
+impl LevelDifficulty {
+    pub fn to_star_difficulty(&self) -> i32 {
+        match self {
+            LevelDifficulty::Auto => 5,
+            LevelDifficulty::Easy => 1,
+            LevelDifficulty::Normal => 2,
+            LevelDifficulty::Hard => 3,
+            LevelDifficulty::Harder => 4,
+            LevelDifficulty::Insane => 5,
+            LevelDifficulty::Demon => 5,
+        }
+    }
+}