from __future__ import annotations

import enum
from datetime import datetime
from typing import ClassVar, Optional

from sqlalchemy import Column, TIMESTAMP
from sqlalchemy import Enum as SAEnum
from sqlmodel import Field, SQLModel


class MeasureType(enum.Enum):
    air_source_heat_pump = "air_source_heat_pump"
    boiler_upgrade = "boiler_upgrade"
    high_heat_retention_storage_heaters = "high_heat_retention_storage_heaters"
    secondary_heating = "secondary_heating"

    roomstat_programmer_trvs = "roomstat_programmer_trvs"
    time_temperature_zone_control = "time_temperature_zone_control"
    cylinder_thermostat = "cylinder_thermostat"

    cavity_wall_insulation = "cavity_wall_insulation"
    extension_cavity_wall_insulation = "extension_cavity_wall_insulation"
    external_wall_insulation = "external_wall_insulation"
    internal_wall_insulation = "internal_wall_insulation"
    loft_insulation = "loft_insulation"
    flat_roof_insulation = "flat_roof_insulation"
    room_roof_insulation = "room_roof_insulation"
    solid_floor_insulation = "solid_floor_insulation"
    suspended_floor_insulation = "suspended_floor_insulation"

    double_glazing = "double_glazing"
    secondary_glazing = "secondary_glazing"
    draught_proofing = "draught_proofing"

    mechanical_ventilation = "mechanical_ventilation"
    low_energy_lighting = "low_energy_lighting"
    solar_pv = "solar_pv"
    hot_water_tank_insulation = "hot_water_tank_insulation"
    sealing_open_fireplace = "sealing_open_fireplace"


class InstalledMeasureModel(SQLModel, table=True):
    """The single SQLModel definition of the live ``installed_measure`` table
    (ADR-0017 amendment). ``measure_type`` is the ``MeasureType`` Postgres enum;
    the remaining NOT-NULLs are relaxed to nullable (mirror convention — the
    live constraints are owned by the Drizzle schema)."""

    __tablename__: ClassVar[str] = "installed_measure"  # pyright: ignore[reportIncompatibleVariableOverride]

    id: Optional[int] = Field(default=None, primary_key=True)
    uprn: Optional[int] = Field(default=None, index=True)
    measure_type: MeasureType = Field(
        sa_column=Column(
            SAEnum(
                MeasureType,
                name="measure_type",
                values_callable=lambda cls: [m.value for m in cls],  # pyright: ignore[reportUnknownLambdaType, reportUnknownMemberType, reportUnknownVariableType]
                create_type=False,
            ),
            nullable=False,
        )
    )
    installed_at: Optional[datetime] = Field(
        default=None, sa_column=Column(TIMESTAMP, nullable=True)
    )
    sap_points: Optional[float] = Field(default=None)
    carbon_savings: Optional[float] = Field(default=None)
    kwh_savings: Optional[float] = Field(default=None)
    bill_savings: Optional[float] = Field(default=None)
    heat_demand_savings: Optional[float] = Field(default=None)
    source: Optional[str] = Field(default=None)
    is_active: bool = True