Common enemy rework

backend/app/services/events.py

@@ -4,7 +4,7 @@ from sqlalchemy.orm import selectinload
 from sqlalchemy.orm.attributes import flag_modified
 from sqlalchemy.ext.asyncio import AsyncSession
 
-from app.models import Event, EventType, Marathon, Challenge, Difficulty
+from app.models import Event, EventType, Marathon, Challenge, Difficulty, Participant, Assignment, AssignmentStatus
 from app.schemas.event import EventEffects, EVENT_INFO, COMMON_ENEMY_BONUSES
 
 
@@ -76,6 +76,12 @@ class EventService:
             data=data if data else None,
         )
         db.add(event)
+        await db.flush()  # Get event.id before committing
+
+        # Auto-assign challenge to all participants for Common Enemy
+        if event_type == EventType.COMMON_ENEMY.value and challenge_id:
+            await self._assign_common_enemy_to_all(db, marathon_id, event.id, challenge_id)
+
         await db.commit()
         await db.refresh(event)
 
@@ -85,14 +91,58 @@ class EventService:
 
         return event
 
+    async def _assign_common_enemy_to_all(
+        self,
+        db: AsyncSession,
+        marathon_id: int,
+        event_id: int,
+        challenge_id: int,
+    ) -> None:
+        """Create event assignments for all participants in the marathon"""
+        # Get all participants
+        result = await db.execute(
+            select(Participant).where(Participant.marathon_id == marathon_id)
+        )
+        participants = result.scalars().all()
+
+        # Create event assignment for each participant
+        for participant in participants:
+            assignment = Assignment(
+                participant_id=participant.id,
+                challenge_id=challenge_id,
+                status=AssignmentStatus.ACTIVE.value,
+                event_type=EventType.COMMON_ENEMY.value,
+                is_event_assignment=True,
+                event_id=event_id,
+            )
+            db.add(assignment)
+
     async def end_event(self, db: AsyncSession, event_id: int) -> None:
-        """End an event"""
+        """End an event and mark incomplete event assignments as expired"""
+        from sqlalchemy import update
+
         result = await db.execute(select(Event).where(Event.id == event_id))
         event = result.scalar_one_or_none()
         if event:
             event.is_active = False
             if not event.end_time:
                 event.end_time = datetime.utcnow()
+
+            # Mark all incomplete event assignments for this event as dropped
+            if event.type == EventType.COMMON_ENEMY.value:
+                await db.execute(
+                    update(Assignment)
+                    .where(
+                        Assignment.event_id == event_id,
+                        Assignment.is_event_assignment == True,
+                        Assignment.status == AssignmentStatus.ACTIVE.value,
+                    )
+                    .values(
+                        status=AssignmentStatus.DROPPED.value,
+                        completed_at=datetime.utcnow(),
+                    )
+                )
+
             await db.commit()
 
     async def consume_jackpot(self, db: AsyncSession, event_id: int) -> None: