1 files changed, 62 insertions, 0 deletions
diff --git a/src/gamedata.rs b/src/gamedata.rs
index f880ba6..9f0f9d4 100644
--- a/src/gamedata.rs
+++ b/src/gamedata.rs
@@ -345,6 +345,53 @@ impl Display for Encounter {
     }
 }
 
+macro_rules! ordering_group {
+    ($self:expr, $other:expr ; $($group:expr;)*) => {
+        $(
+            let group = &$group;
+            if let Some(pos_a) = group.iter().position(|x| *x == $self) {
+                if let Some(pos_b) = group.iter().position(|x| *x == $other) {
+                    return Some(pos_a.cmp(&pos_b));
+                }
+            }
+        )*
+    }
+}
+
+// We could implement (or even derive) PartialOrd for all bosses, but there is no "canonical" order
+// (do fractal bosses come before raid bosses or after?). This implements a conservative order,
+// such that at least the bosses that appear in a single raid wing/fractal are ordered relative to
+// each other, but there is no order between different wings. This still allows some useful cases
+// (like sorting bosses within a wing).
+//
+// There are some edge cases, like the Wing 5 events (Eater/Eyes/Broken King) and Adina/Sabir,
+// which technically happen at the same time, but we're just defining a fixed order for those here.
+//
+// In the future, this implementation might be expanded to a total order, but by keeping it a
+// partial order for now we can implement the cases that are clear (bosses within a wing) while
+// allowing future extensions in a backwards-compatible way (once we figured out how we want to
+// order the different wings/strikes/fractals).
+impl PartialOrd for Encounter {
+    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
+        use Encounter::*;
+        ordering_group!(*self, *other;
+            // Raids
+            [ValeGuardian, Gorseval, Sabetha];
+            [Slothasor, BanditTrio, Matthias];
+            [KeepConstruct, TwistedCastle, Xera];
+            [Cairn, MursaatOverseer, Samarog, Deimos];
+            [SoullessHorror, RiverOfSouls, BrokenKing, EaterOfSouls, StatueOfDarkness, VoiceInTheVoid];
+            [ConjuredAmalgamate, TwinLargos, Qadim];
+            [CardinalAdina, CardinalSabir, QadimThePeerless];
+            // Shattered Observatory CM
+            [Skorvald, Artsariiv, Arkk];
+            // Nightmare CM
+            [MAMA, Siax, Ensolyss];
+        );
+        None
+    }
+}
+
 /// Enum containing all boss IDs.
 ///
 /// For a high-level event categorization, take a look at the [`Encounter`] enum. The IDs listed
@@ -1142,6 +1189,21 @@ mod tests {
     }
 
     #[test]
+    fn test_encounter_partial_cmp() {
+        // Just a few example cases
+        use Encounter::*;
+        assert!(ValeGuardian < Gorseval);
+        assert!(ValeGuardian < Sabetha);
+        assert!(Gorseval < Sabetha);
+        assert!(ValeGuardian.partial_cmp(&Slothasor).is_none());
+
+        assert!(VoiceInTheVoid > SoullessHorror);
+        assert!(Qadim > TwinLargos);
+
+        assert!(Ankka.partial_cmp(&Dragonvoid).is_none());
+    }
+
+    #[test]
     fn test_boss_parsing_ok() {
         use Boss::*;
         let tests: &[(&'static str, Boss)] = &[