Files
plm-lottery/app/bets/service.py
T
davideandClaude Sonnet 5 f21ecbd4ee Add a cooldown between rounds (ROUND_COOLDOWN_SECONDS)
open_new_round_if_needed now withholds opening the next round until
ROUND_COOLDOWN_SECONDS (default 30) have passed since the previous
round's closed_at, returning None in that window instead of a Round.
Without this, the next round opened within one scheduler tick (~5s) of
the previous payout confirming — not enough time for a player to
notice the round they were in actually resolved.

Callers updated: the scheduler treats None as "nothing to do this
tick", and place_bet raises a "try again shortly" BetError instead of
crashing on a None round.

Not in the original flowchart — a deliberate UX addition on top of it,
documented as such in CLAUDE.md.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
2026-07-21 11:29:59 +02:00

107 lines
3.5 KiB
Python

from datetime import datetime, timezone
from embit import script
from sqlalchemy import select
from sqlalchemy.ext.asyncio import AsyncSession
from app.audit.log import write_audit_log
from app.config import settings
from app.db.models import PendingTransaction, RoundParticipant, User, UtxoEvent
from app.electrum.client import ElectrumClient
from app.rounds.config import get_round_config
from app.rounds.service import open_new_round_if_needed
from app.wallet.balance import recompute_balance
from app.wallet.hd import derive_pool_address, derive_user_key
from app.wallet.psbt_builder import BuiltTransaction, InsufficientFundsError, Utxo, build_signed_transaction
class BetError(Exception):
pass
async def place_bet(session: AsyncSession, client: ElectrumClient, user: User) -> RoundParticipant:
round_ = await open_new_round_if_needed(session)
if round_ is None:
raise BetError("no round open right now, please try again shortly")
if round_.status != "open":
raise BetError("the current round is closing, please try again shortly")
already_playing = await session.scalar(
select(RoundParticipant).where(
RoundParticipant.round_id == round_.id, RoundParticipant.user_id == user.id
)
)
if already_playing is not None:
raise BetError("you already have an active bet in the current round")
config = await get_round_config(session)
bet_amount = config.bet_amount_sats
unspent = (
await session.scalars(
select(UtxoEvent).where(UtxoEvent.user_id == user.id, UtxoEvent.spent_txid.is_(None))
)
).all()
if sum(u.amount_sats for u in unspent) < bet_amount:
raise BetError("insufficient balance")
user_key = derive_user_key(user.derivation_index)
from_script = script.p2wpkh(user_key.to_public())
utxos = [Utxo(u.txid, u.vout, u.amount_sats) for u in unspent]
try:
built = build_signed_transaction(
signing_key=user_key,
from_script=from_script,
utxos=utxos,
to_address=derive_pool_address(),
amount_sats=bet_amount,
change_address=user.address,
fee_rate_sat_vb=settings.fee_rate_sat_vb,
)
except InsufficientFundsError as exc:
raise BetError(str(exc)) from exc
await client.broadcast(built.raw_hex)
spent_by_key = {(u.txid, u.vout): u for u in unspent}
for spent in built.spent_utxos:
row = spent_by_key[(spent.txid, spent.vout)]
row.spent_txid = built.txid
await recompute_balance(session, user.id)
broadcast_at = datetime.now(timezone.utc)
participant = RoundParticipant(
round_id=round_.id,
user_id=user.id,
bet_amount_sats=built.recipient_sats,
bet_txid=built.txid,
broadcast_at=broadcast_at,
status="broadcast",
)
session.add(participant)
session.add(_pending_transaction(round_.id, user.id, built))
await write_audit_log(
session,
"bet_placed",
{"txid": built.txid, "amount_sats": built.recipient_sats},
user_id=user.id,
round_id=round_.id,
)
await session.commit()
await session.refresh(participant)
return participant
def _pending_transaction(round_id: int, user_id: int, built: BuiltTransaction) -> PendingTransaction:
return PendingTransaction(
kind="bet",
round_id=round_id,
user_id=user_id,
current_txid=built.txid,
fee_rate_sat_vb=settings.fee_rate_sat_vb,
raw_tx_hex=built.raw_hex,
status="pending",
)