fix(market): per-event bet loss+win

polylan_submitter/market/api.py

@@ -6,12 +6,19 @@ from django.db.models import Sum, Prefetch
 from django.db.models.functions import Coalesce
 from django.db import transaction
 
-from market.models import Market, MarketOption, UserBet, UserPointChange
+from market.models import (
+    Market,
+    MarketOption,
+    UserBet,
+    UserPointChange,
+    get_event_points,
+)
 from market.schemas import (
     MarketListSchema,
     ResolveMarketSchema,
     UserBetCreateSchema,
     UserBetSchema,
+    UserPointsSchema,
 )
 
 
@@ -45,6 +52,15 @@ def list_user_bets(request, event_path: str):
     )
 
 
+@router.get(f"{PREFIX}/user/points", response=UserPointsSchema)
+def get_user_points(request, event_path: str):
+    """Get the current user's points balance for this event."""
+    if not request.user.is_authenticated:
+        raise HttpError(401, "Authentication required")
+
+    return {"points": get_event_points(request.user, request.event)}
+
+
 @router.post(f"{PREFIX}/{{market_uuid}}/actions/close")
 def close_market(request, event_path: str, market_uuid: str):
     """Close a market. Admin only."""
@@ -76,9 +92,7 @@ def resolve_market(
     market.save(update_fields=["winning_option", "status", "updated_at"])
 
     # Calculate and distribute winnings
-    all_bets = list(
-        UserBet.objects.filter(option__market=market).select_related("user")
-    )
+    all_bets = list(UserBet.objects.filter(option__market=market))
 
     # Calculate total pot
     total_pot = sum(bet.amount for bet in all_bets)
@@ -92,7 +106,6 @@ def resolve_market(
     total_winning = sum(bet.amount for bet in winning_bets)
 
     point_changes = []
-    users_to_update = []
 
     with transaction.atomic():
         # Award payouts to winners with multiplier
@@ -101,11 +114,9 @@ def resolve_market(
                 payout = round(
                     bet.amount / total_winning * total_pot * market.multiplier
                 )
-                bet.user.points += payout
-                users_to_update.append(bet.user)
                 point_changes.append(
                     UserPointChange(
-                        user=bet.user,
+                        user_id=bet.user_id,
                         market=market,
                         amount=payout,
                         reason=UserPointChange.Reason.BET_WON,
@@ -116,17 +127,13 @@ def resolve_market(
         for bet in losing_bets:
             point_changes.append(
                 UserPointChange(
-                    user=bet.user,
+                    user_id=bet.user_id,
                     market=market,
                     amount=-bet.amount,
                     reason=UserPointChange.Reason.BET_LOST,
                 )
             )
 
-        # Bulk update users
-        for user in users_to_update:
-            user.save(update_fields=["points"])
-
         # Bulk create point changes
         UserPointChange.objects.bulk_create(point_changes)
 
@@ -167,8 +174,8 @@ def create_bet(
     # Calculate delta (amount to deduct from user's points)
     delta = payload.amount - (existing_bet.amount if existing_bet else 0)
 
-    # Check if user has enough points
-    if request.user.points < delta:
+    # Check if user has enough points for this event
+    if get_event_points(request.user, request.event) < delta:
         raise HttpError(400, "Insufficient points for this bet")
 
     user_bet, created = UserBet.objects.update_or_create(
@@ -177,9 +184,7 @@ def create_bet(
         defaults={"amount": payload.amount},
     )
 
-    # Deduct points and record the change
-    request.user.points -= delta
-    request.user.save(update_fields=["points"])
+    # Record the change (the event balance is derived from these)
     UserPointChange.objects.create(
         user=request.user,
         market=market,

polylan_submitter/market/models.py

@@ -1,10 +1,28 @@
 import uuid
 from django.db import models
+from django.db.models import Sum
 
 from events.models import Event
 from events.scoping import EventScopedManager
 
 
+# Each event's market starts every user with this balance
+STARTING_POINTS = 1000
+
+
+def get_event_points(user, event) -> int:
+    """User's market balance for an event: starting points + the event's point changes.
+
+    BET_LOST rows are informational (the stake was already deducted by BET_PLACED).
+    """
+    total = (
+        UserPointChange.objects.filter(user=user, market__event=event)
+        .exclude(reason=UserPointChange.Reason.BET_LOST)
+        .aggregate(total=Sum("amount"))["total"]
+    )
+    return STARTING_POINTS + (total or 0)
+
+
 class BaseModel(models.Model):
     uuid = models.UUIDField(default=uuid.uuid4, unique=True, editable=False)
     created_at = models.DateTimeField(auto_now_add=True)

polylan_submitter/market/schemas.py

@@ -35,6 +35,10 @@ class ResolveMarketSchema(Schema):
     winning_option_uuid: str
 
 
+class UserPointsSchema(Schema):
+    points: int
+
+
 class UserBetCreateSchema(Schema):
     option_uuid: str
     amount: int