"""Per-person notification preferences — the employee's control surface over
the outbound notification firehose.

One row per person (PK = person id). Absence of a row means "all defaults"
(every channel on, no quiet hours) so the table is sparse: only people who
have actually tuned something carry a row. ``NotificationPreferenceService``
treats a missing row identically to an all-default row.

Two governed dimensions:
  * ``muted_channels`` — ``{category_key: ["feishu", "email"]}``. Listing a
    channel under a category suppresses that *push* channel for notifications
    in that category. The in-app inbox row is ALWAYS written (muting reduces
    interruptions; it never loses the record). Critical templates
    (``is_critical_template``) ignore this entirely.
  * quiet hours — a daily local-time window (resolved in the recipient's own
    timezone) during which non-critical push is parked and re-delivered when
    the window ends. ``start``/``end`` are ``"HH:MM"`` strings; a window where
    start > end (e.g. 22:00→08:00) crosses midnight.
"""
from __future__ import annotations

import uuid
from datetime import datetime
from typing import Any

from sqlalchemy import JSON, Boolean, DateTime, ForeignKey, String, func
from sqlalchemy.orm import Mapped, mapped_column

from app.core.database import Base
from app.core.sql_types import GUID as Uuid


class NotificationPreference(Base):
    __tablename__ = "notification_preferences"

    # PK == person id (1:1). No surrogate key — the person owns exactly one
    # preference row and we always look it up by person id.
    person_id: Mapped[uuid.UUID] = mapped_column(
        Uuid, ForeignKey("identity_persons.id"), primary_key=True,
    )

    # {category_key: [channel, ...]} — channels muted for that category.
    muted_channels: Mapped[dict[str, Any]] = mapped_column(
        JSON, nullable=False, default=dict,
    )

    quiet_hours_enabled: Mapped[bool] = mapped_column(
        Boolean, nullable=False, server_default="0", default=False,
    )
    # "HH:MM" local-time bounds. NULL when quiet hours disabled.
    quiet_hours_start: Mapped[str | None] = mapped_column(String(5))
    quiet_hours_end: Mapped[str | None] = mapped_column(String(5))

    created_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True), nullable=False, server_default=func.now(),
    )
    updated_at: Mapped[datetime] = mapped_column(
        DateTime(timezone=True), nullable=False,
        server_default=func.now(), onupdate=func.now(),
    )


__all__ = ["NotificationPreference"]