from django.core.management.base import BaseCommand, CommandError
from monthplan.models import SurveyHealpixPlate, SurveyHealpixSubPlate, NSIDE_PLATES, NSIDE_SUBPLATES, ORDER

from os import listdir
from astropy_healpix import HEALPix
from astropy import units as u
from astropy.coordinates import SkyCoord, RangeError
from astropy.coordinates import ICRS, Galactic, FK5
from astropy.coordinates import Angle


def init_healpix_sub_plates(nside_plates, nside_subplates, order):
    hp_plates = HEALPix(nside=nside_plates, order=order, frame=FK5())
    hp_subplates = HEALPix(nside=nside_subplates, order=order, frame=FK5())

    print("Make Healpix Plates",hp_plates.npix,hp_plates.pixel_area.value,hp_plates.pixel_resolution.value)
    print("Make Healpix SubPlates",hp_subplates.npix,hp_subplates.pixel_area.value,hp_subplates.pixel_resolution.value)
    try:
        print('Delete existing Healpix Plates')
        subplates = SurveyHealpixSubPlate.objects.all()
        subplates.delete()
    except:
        print('Abort')
        exit()    

    for heal in range(hp_subplates.npix):
        sc = hp_subplates.healpix_to_skycoord(heal)
        crd = SkyCoord(float(sc.ra.degree), float(sc.dec.degree), frame="fk5", unit="deg")
        heal = hp_plates.skycoord_to_healpix(crd)
        try:
            plate = SurveyHealpixPlate.objects.get(healpix=heal)
        except:
            print('Error: SurveyHealpixPlate not found, run ./manage.py init_survey_healpix_plates first')
            return
        subplate = SurveyHealpixSubPlate(healpix=heal, ra=float(sc.ra.degree), dec=float(sc.dec.degree), plate=plate)
        subplate.save()
    pass

class Command(BaseCommand):

    def handle(self, *args, **options):
        init_healpix_sub_plates(NSIDE_PLATES, NSIDE_SUBPLATES, ORDER)