Distinguish round-closing sub-phases and anchor cooldown to payout confirmation

Flip status to "closing" the instant the round timer expires, rather than
leaving it "open" (invisible) while in-flight bets confirm — /rounds/current
now surfaces this wait as its own phase instead of collapsing it into
"drawing". _tick() is updated to keep re-checking pending bets while status
is "closing" instead of short-circuiting on the old "status != open" guard.

Also re-stamp closed_at at actual payout confirmation time (not at the
earlier "closing" transition), since round_cooldown_seconds counts from
closed_at — with a short cooldown (e.g. 20s) and ~2 block-time draw+payout
wait, the old anchor meant the cooldown had already elapsed by the time the
round actually closed, making it a no-op.

Expose draw_block_height/draw_block_hash on GET /rounds/current so clients
can show which block the winner was drawn from.

app/api/routes/rounds.py

@@ -25,6 +25,8 @@ class CurrentRoundResponse(BaseModel):
     draw_animation_seconds: int
     winner_user_id: int | None = None
     winner_amount_sats: int | None = None
+    draw_block_height: int | None = None
+    draw_block_hash: str | None = None
     chain_tip_height: int | None = None
     lottery_paused: bool = False
 
@@ -70,6 +72,8 @@ async def current_round(request: Request, session: AsyncSession = Depends(get_se
         draw_animation_seconds=config.draw_animation_seconds,
         winner_user_id=round_.winner_user_id,
         winner_amount_sats=round_.winner_amount_sats,
+        draw_block_height=round_.draw_block_height,
+        draw_block_hash=round_.draw_block_hash,
         chain_tip_height=chain_tip_height,
         lottery_paused=config.paused,
     )

app/rounds/confirmation.py

@@ -1,3 +1,5 @@
+from datetime import datetime, timezone
+
 from sqlalchemy import select
 from sqlalchemy.ext.asyncio import AsyncSession
 
@@ -9,6 +11,12 @@ async def _on_payout_confirmed(session: AsyncSession, pending: PendingTransactio
     round_ = await session.scalar(select(Round).where(Round.payout_txid == pending.current_txid))
     if round_ is not None and round_.status == "paying_out":
         round_.status = "closed"
+        # closed_at is what round_cooldown_seconds counts from (service.py's
+        # open_new_round_if_needed) — re-stamp it here at actual payout
+        # confirmation time rather than leaving it at the earlier "closing"
+        # timestamp, so a short cooldown (e.g. 20s) is a real pause after the
+        # winner's tx confirms, not swallowed by the ~2 block-time draw+payout wait.
+        round_.closed_at = datetime.now(timezone.utc)
         # The winner's own address is already watched by the Electrum listener, so
         # their balance is credited by the normal deposit path once this confirms.
 

app/rounds/scheduler.py

@@ -54,12 +54,23 @@ class RoundScheduler:
             round_id, status, opened_at = round_.id, round_.status, round_.opened_at
             round_duration_seconds = (await get_round_config(session)).round_duration_seconds
 
-        if status != "open":
-            return  # already closing/drawing/paying_out; progress happens elsewhere
+        if status not in ("open", "closing"):
+            return  # already drawing/paying_out; progress happens elsewhere
 
-        opened_at = opened_at.replace(tzinfo=timezone.utc)
-        if datetime.now(timezone.utc) < opened_at + timedelta(seconds=round_duration_seconds):
-            return
+        if status == "open":
+            opened_at = opened_at.replace(tzinfo=timezone.utc)
+            if datetime.now(timezone.utc) < opened_at + timedelta(seconds=round_duration_seconds):
+                return
+
+            async with self._session_factory() as session:
+                round_ = await session.get(Round, round_id)
+                # No new bets from here on, regardless of how long the pending-bet
+                # wait below takes — flip to "closing" immediately so it's observable
+                # via /rounds/current (e.g. "round closed, waiting for jackpot
+                # confirmation") instead of silently staying "open" past the deadline.
+                round_.status = "closing"
+                round_.closed_at = datetime.now(timezone.utc)
+                await session.commit()
 
         async with self._session_factory() as session:
             pending_count = await session.scalar(
@@ -68,19 +79,13 @@ class RoundScheduler:
                 .where(RoundParticipant.round_id == round_id, RoundParticipant.status == "broadcast")
             )
         if pending_count:
-            return  # wait for in-flight bets to confirm before closing
+            return  # wait for in-flight bets to confirm before closing; stays "closing"
 
         await self._close_and_draw(round_id)
 
     async def _close_and_draw(self, round_id: int) -> None:
         async with self._session_factory() as session:
             round_ = await session.get(Round, round_id)
-            round_.status = "closing"
-            round_.closed_at = datetime.now(timezone.utc)
-            # Committed on its own so "closing" is actually observable (e.g. by
-            # /rounds/current) instead of being overwritten in memory by "closed"
-            # or "drawing" below before ever reaching the database.
-            await session.commit()
 
             participants = (
                 await session.scalars(