"""Domain entity: TipDismissal.

A workspace-scoped record that a specific tip (`Tip.id`, see
`app.services.tips_service`) has been acknowledged/dismissed by the user.
Keyed by (workspace_id, tip_id) — see the UNIQUE constraint on the
`tip_dismissal` table — so re-dismissing the same tip refreshes `data_hash`
and `dismissed_at` instead of creating a duplicate row.

`data_hash` snapshots `app.utils.tip_predicates.hash_tip_data(tip.data)` at
dismiss time. `TipsService` only treats a dismissal as active while the
rule's *current* output hashes to the same value — once the underlying
numbers move (more days now projected to expire at age 4, a different
`fourth_birthday`, ...), the dismissal is stale and the tip resurfaces. See
`TipsService._filter_dismissed` for why: permanently silencing a warning like
`preserve_for_age_4` because its *old* figures were once dismissed would be
dangerous.
"""

from dataclasses import dataclass
from datetime import datetime
from uuid import UUID


@dataclass
class TipDismissal:
    id: UUID
    workspace_id: UUID
    tip_id: str
    data_hash: str
    dismissed_at: datetime | None = None