Source code for ctao_datamodel.models.common

"""Implementations of the CTAO Common Data Model Specification."""

from enum import StrEnum, nonmember
from typing import ClassVar

import astropy.units as u
from astropydantic import AstroPydanticUnit

from .._core import AstroField, ModelBase, Quantity, enum_doc

__all__ = ["SiteID", "TimeRefPos", "TimeSystem", "TimeReference"]

_NAMESPACE = "CTAO.Common"




class SiteID(StrEnum):
    """CTAO sites."""

    _namespace = nonmember(_NAMESPACE)

    SDMC_SUSS = "SDMC-SUSS"  #: Data created by SUSS at the SDMC
    CTAO_NORTH = "CTAO-North"  #: Data created at CTAO North
    CTAO_SOUTH = "CTAO-South"  #: Data created at CTAO South
    SDMC_DPPS = "SDMC-DPPS"  #: Data created by DPPS at the SDMC
    HQ = "HQ"  #: Data created at CTAO Headquarters
    EXTERNAL = "EXTERNAL"  #: Data external to CTAO





class TimeRefPos(StrEnum):
    """
    Spatial location at which the observation time is valid.

    From FITS standard v4
    """

    _namespace = nonmember(_NAMESPACE)
    TOPOCENTER = "TOPOCENTER"
    RELOCATABLE = "RELOCATABLE"





class TimeSystem(StrEnum):
    """The time scale of the time-related keywords.

    For simulated data, use LOCAL.
    """

    _namespace = nonmember(_NAMESPACE)
    TT = "TT"  #: Terrestrial Time
    UTC = "UTC"  #: Coordinated Universal Time
    UT1 = "UT1"  #: Universal Time
    TAI = "TAI"  #: International Atomic Time
    GPS = "GPS"  #: Global Positioning System time
    LOCAL = "LOCAL"  #: Local Time





class TimeReference(ModelBase):
    """
    Reference time for floating point time representations.

    For timestamps represented as ISO time strings, this is not relevant.
    """

    _namespace: ClassVar[str] = _NAMESPACE

    position: TimeRefPos = AstroField(enum_doc(TimeRefPos), fits_keyword="TREFPOS")
    time_mjd: Quantity[u.day] = AstroField(
        "Reference time in MJD", fits_keyword="MJDREF"
    )
    unit: AstroPydanticUnit = AstroField(default="s", fits_keyword="TIMEUNIT")
    system: TimeSystem = AstroField(
        enum_doc(TimeSystem), default=TimeSystem.TAI, fits_keyword="TIMESYS"
    )
    resolution: float | None = AstroField(
        "time resolution in the time unit.",
        default=None,
        fits_keyword="TIMEDELT",
        ivoa_keyword="t_resolution",
    )