from django.core.management.base import BaseCommand, CommandError

from datetime import date
from django.utils import dateparse
from logbook.models import LogBookPlan, LogBookDay
from plan.models import INPUT_DATA_DIR
from plan.models import LaunchDate

from monthplan.models import Head, Observation, Seance, Correction, Scan, Survey, FlightPlan

from astropy.io import fits

from django.utils import timezone


from astropy.io import fits
import pandas as pd
from pandas import ExcelWriter
from pandas import ExcelFile
#import xlrd
from astropy.table import Table

import math

import astropy.units as u
from astropy.time.formats import erfa
from astropy.time import Time, TimeDelta, TimezoneInfo, TimeFromEpoch
from datetime import datetime

MJDREF = 51543.875
TZ_UTC = TimezoneInfo(utc_offset=0*u.hour)
TZ_MSK = TimezoneInfo(utc_offset=3*u.hour)

# 2019-08-01T02:28:00+03:00
TIMESTR_FORMAT = '%Y-%m-%dT%H:%M:%S+03:00'

def str2date(timestr, tzone):
    time_raw   = datetime.strptime(timestr, TIMESTR_FORMAT)
    time_zoned = time_raw.replace(tzinfo=tzone)
    return time_zoned


def date2mission(dtime):
    mjdref = Time(MJDREF, format='mjd')
    dtime  = Time(dtime , format='datetime')
    return (dtime - mjdref).sec


def mission2date(timesec, tzone):
    mjdref = Time(MJDREF, format='mjd')
    delta = TimeDelta(timesec, format='sec')
    dtime = mjdref + delta + 3*u.hour
    return dtime.to_datetime()

def print_obsplan_dt_sec(dtstr):
    dt = str2date(dtstr, tzone=TZ_MSK)
    ts = date2mission(dt)
    print(dt, '-->', ts)

def print_pz_dt_sec(dtstr):
    dt = str2date(dtstr, tzone=TZ_UTC)
    ts = date2mission(dt)
    print(dt, '-->', ts)

def load_data(file):
    print('Load data (dummy)')
    fitsfile=INPUT_DATA_DIR+'/'+file
    table = Table.read(fitsfile)
    df = table.to_pandas()
    print("Column headings:")
    print(df.columns.str.encode('utf-8'))
    hdul = fits.open(fitsfile)
    hdul.info()
    for i in df.index:
        dtstr=df['START'][i].decode().strip()
        dt = str2date(dtstr, tzone=TZ_MSK)
        start_ts = date2mission(dt)

        dtstr=df['STOP'][i].decode().strip()
        dt = str2date(dtstr, tzone=TZ_MSK)
        stop_ts = date2mission(dt)
        #print(dt, '-->', ts)
        
        obs=FlightPlan()
        obs.start=df['START'][i].decode().strip()
        obs.stop=df['STOP'][i].decode().strip()
        obs.experiment=df['EXPERIMENT'][i].decode().strip()
        obs.ra=df['RA'][i]
        obs.dec=df['DEC'][i]
        obs.q1=df['Q1'][i]
        obs.q2=df['Q2'][i]
        obs.q3=df['Q3'][i]
        obs.q4=df['Q4'][i]
        obs.start_npol = df['START_NPOL'][i].decode().strip()
        obs.stop_npol  = df['STOP_NPOL'][i].decode().strip()
        obs.load_stamp = df['LOAD_STAMP'][i].decode().strip()
        obs.mjd_start  = df['MJD_START'][i]
        obs.mjd_stop   = df['MJD_STOP'][i]
        obs.obt_start  = start_ts # df['OBT_START'][i]
        obs.obt_stop   = stop_ts # df['OBT_STOP'][i]
        obs.save()
        print(df['EXPERIMENT'][i])
    pass

def validate_flightplan():
    list = FlightPlan.objects.all()
    for pz in list:
        if (pz.experiment == '00000000000' and pz.valid == True):
            pz.valid = False
            pz.save()
            continue
        first = FlightPlan.objects.filter(experiment__exact=pz.experiment).order_by("-load_stamp")[0]
        first.valid = True
        first.save()
    pass

class Command(BaseCommand):
    help = 'Initiates data base'

#    def add_arguments(self, parser):
#        parser.add_argument('poll_id', nargs='+', type=int)

    def handle(self, *args, **options):
        pz = FlightPlan.objects.all()
        pz.delete()
        load_data('pz.fits')
        validate_flightplan()