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

from datetime import date
from heasarc.models import INPUT_DATA_DIR
import datetime
from django.utils import timezone
import astropy
from astropy.io import ascii
import pandas as pd
import pymysql
from sqlalchemy import create_engine

from heasarc.tdat import tDat
from heasarc.models import HeasarcTable, TableColumn, HeasarcObjectClass

def load_heasarc_table(filename, engine):
    tdatfile=INPUT_DATA_DIR+'/dump/'+filename
    data = astropy.table.Table.read(tdatfile, format='ascii.tdat')

    keywords = data.meta['keywords']
    for key, value in keywords.items():
            print(key, '->', value)

            try:
                table=HeasarcTable.objects.get(name__exact=keywords['table_name'])
                table.delete()
            except:
                pass

            table_name=keywords['table_name']
            table = HeasarcTable(name=keywords['table_name'])
            table.description=keywords['table_description'].replace('\"', '')
            table.document_url=keywords['table_document_url']
            if 'default_search_radius' in keywords:
                table.search_radius=int(keywords['default_search_radius'])
            if 'frequency_regime' in keywords:
                table.frequency_regime=keywords['frequency_regime']
            table.observatory_name=keywords['observatory_name']
            table.security=keywords['table_security']
            if 'table_author' in keywords:
                table.author=keywords['table_author']
            if 'catalog_bibcode' in keywords:
                table.bibcode=keywords['catalog_bibcode']
            if 'declination' in keywords:
                table.declination=keywords['declination'].replace('@', '')
            if 'right_ascension' in keywords:
                table.right_ascension=keywords['right_ascension'].replace('@', '')
            table.observatory_name = keywords['observatory_name']
            if 'parameter_defaults' in keywords:
                table.parameter_defaults = keywords['parameter_defaults']
            table.save()

    cols = data.meta['cols']
    for key, value in cols.items():
        column = TableColumn(table=table)
        column.name=key
        column.tdat_type=value['type']
        column.description=value['description']
        column.save()
        print(key, '->', value)

        # convert data frame to pandas                                                                                                           
    df = data.to_pandas()
    sql = 'DROP TABLE IF EXISTS '+table_name+';'
    result = engine.execute(sql)

    # Insert whole DataFrame into MySQL                                                                            
    df.to_sql(table_name, con = engine, if_exists = 'append', chunksize = 200000)
    
    for item in data:
        obj = HeasarcObjectClass(table=table, 
                                 class_id=int(item['class_id']), 
                                 class_name=item['class_name'])
        obj.save()

    print('--> Successfully loaded "%s"' % table_name)
    pass

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

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

    def handle(self, *args, **options):
        
        load_heasarc_table('heasarc_class.tdat.gz', engine)
        self.stdout.write(self.style.SUCCESS('Done'))