"""SQLModel mirror of the ``landlord_main_heating_system_overrides`` Drizzle table.

The schema source of truth lives in the ``assessment-model`` TS repo
(`src/app/db/schema/landlord_overrides.ts`). The migrations are owned there;
this row class only mirrors the columns so the Python lambda can read/write.
See ADR-0003. Shape mirrors ``LandlordWallTypeOverrideRow`` -- the only
differences are the table name, the ``main_heating_system`` pgEnum on ``value``,
and the unique-constraint name.
"""

from datetime import datetime, timezone
from typing import ClassVar
from uuid import UUID, uuid4

from sqlalchemy import BigInteger, Column, UniqueConstraint
from sqlalchemy import Enum as SAEnum
from sqlmodel import Field, SQLModel

from domain.epc.property_overrides.main_heating_system_type import MainHeatingSystemType
from infrastructure.postgres.landlord_override_enums import override_source_sa_enum


class LandlordMainHeatingSystemOverrideRow(SQLModel, table=True):
    __tablename__: ClassVar[str] = "landlord_main_heating_system_overrides"  # pyright: ignore[reportIncompatibleVariableOverride]
    __table_args__: ClassVar[tuple[UniqueConstraint, ...]] = (  # pyright: ignore[reportIncompatibleVariableOverride]
        # Shortened (drop the redundant ``_overrides``) to stay within
        # PostgreSQL's 63-char identifier limit; mirrors the Drizzle name.
        UniqueConstraint(
            "portfolio_id",
            "description",
            name="landlord_main_heating_system_portfolio_description_unique",
        ),
    )

    id: UUID = Field(default_factory=uuid4, primary_key=True)

    # bigint to match the Drizzle ``portfolio_id`` FK; SQLModel's default int
    # mapping is 32-bit Integer and would overflow once portfolio IDs exceed
    # 2^31. The FK to ``portfolio.id`` is enforced by the Drizzle migration,
    # not declared here -- the ``portfolio`` table is not modelled in Python.
    portfolio_id: int = Field(
        sa_column=Column(BigInteger, nullable=False, index=True),
    )

    description: str = Field(nullable=False)

    value: MainHeatingSystemType = Field(
        sa_column=Column(
            SAEnum(
                MainHeatingSystemType,
                name="main_heating_system",
                values_callable=lambda cls: [m.value for m in cls],  # pyright: ignore[reportUnknownLambdaType, reportUnknownMemberType, reportUnknownVariableType]
            ),
            nullable=False,
        ),
    )

    # Shared SAEnum -- see ``landlord_override_enums`` for why this single
    # instance is reused by every ``landlord_*_overrides`` row class.
    source: str = Field(
        sa_column=Column(override_source_sa_enum, nullable=False),
    )

    created_at: datetime = Field(
        default_factory=lambda: datetime.now(timezone.utc),
        nullable=False,
    )
    updated_at: datetime = Field(
        default_factory=lambda: datetime.now(timezone.utc),
        nullable=False,
    )