views.py

import os

from django.http import HttpResponse, JsonResponse, Http404
from django.shortcuts import get_object_or_404, render
from lofar.sas.tmss.tmss.tmssapp import models
from lofar.common.json_utils import get_default_json_object_for_schema
from lofar.common.datetimeutils import formatDatetime
from lofar.sas.tmss.tmss.tmssapp.adapters.parset import convert_to_parset
from drf_yasg.utils import swagger_auto_schema
from drf_yasg.openapi import Parameter
from rest_framework.permissions import AllowAny
from rest_framework.decorators import authentication_classes, permission_classes
from django.apps import apps

from rest_framework.decorators import api_view
from datetime import datetime
import dateutil.parser
from lofar.sas.tmss.tmss.tmssapp.conversions import local_sidereal_time_for_utc_and_station, local_sidereal_time_for_utc_and_longitude, timestamps_and_stations_to_sun_rise_and_set

# Note: Decorate with @api_view to get this picked up by Swagger

def subtask_template_default_specification(request, subtask_template_pk:int):
    subtask_template = get_object_or_404(models.SubtaskTemplate, pk=subtask_template_pk)
    spec = get_default_json_object_for_schema(subtask_template.schema)
    return JsonResponse(spec)


def task_template_default_specification(request, task_template_pk:int):
    task_template = get_object_or_404(models.TaskTemplate, pk=task_template_pk)
    spec = get_default_json_object_for_schema(task_template.schema)
    return JsonResponse(spec)


def subtask_parset(request, subtask_pk:int):
    subtask = get_object_or_404(models.Subtask, pk=subtask_pk)
    parset = convert_to_parset(subtask)
    return HttpResponse(str(parset), content_type='text/plain')


def index(request):
    return render(request, os.path.join(os.environ.get('LOFARROOT'), 'SAS/TMSS/frontend','tmss_webapp/build/index.html'))
    #return render(request, "../../../frontend/frontend_poc/build/index.html")


def task_specify_observation(request, pk=None):
    task = get_object_or_404(models.TaskDraft, pk=pk)
    return HttpResponse("response", content_type='text/plain')

# Allow everybody to GET our publicly available template-json-schema's
@permission_classes([AllowAny])
@authentication_classes([AllowAny])
@swagger_auto_schema(method='GET',
                     responses={200: 'Get the JSON schema from the template with the requested <template>, <name> and <version>',
                                404: 'the schema with requested <template>, <name> and <version> is not available'},
                     operation_description="Get the JSON schema for the given <template> with the given <name> and <version> as application/json content response.")
@api_view(['GET'])
def get_template_json_schema(request, template:str, name:str, version:str):
    template_model = apps.get_model("tmssapp", template)
    template_instance = get_object_or_404(template_model, name=name, version=version)
    schema = template_instance.schema
    response = JsonResponse(schema, json_dumps_params={"indent":2})

    # config Access-Control. Our schemas use $ref url's to other schemas, mainly pointing to our own common schemas with base definitions.
    # We instruct the client to allow fetching those.
    response["Access-Control-Allow-Origin"] = "*"
    response["Access-Control-Allow-Methods"] = "GET, OPTIONS"
    return response


# Allow everybody to GET our publicly available station group lookups
@permission_classes([AllowAny])
@authentication_classes([AllowAny])
@swagger_auto_schema(method='GET',
                     responses={200: 'A JSON object with two properties: group:<the_group_name>, stations:<the_list_of_stations>',
                                404: 'No such group or template available'},
                     operation_description="Get a JSON list of stations for the given <station_group> name the the group definitions in the common_schema_template given by <template_name> and <template_version>")
@api_view(['GET'])
def get_stations_in_group(request, template_name:str, template_version:str, station_group:str):
    station_schema_template = get_object_or_404(models.CommonSchemaTemplate, name=template_name, version=template_version)
    station_schema = station_schema_template.schema

    if 'station_group' not in station_schema.get('definitions', {}):
        raise Http404('The JSON schema in template %s version %s has no station_group definitions' % (template_name, template_version))

    groups = station_schema['definitions']['station_group']['anyOf']
    try:
        selected_group = next(g for g in groups if g['title'].lower() == station_group.lower())
    except StopIteration:
        raise Http404('No station_group with name "%s" found in the JSON schema. template=%s version=%s' % (station_group, template_name, template_version))

    stations = selected_group['properties']['stations']['enum'][0]
    return JsonResponse({'group': station_group,
                         'stations': stations})


@permission_classes([AllowAny])
@authentication_classes([AllowAny])
@swagger_auto_schema(method='GET',
                     responses={200: 'An isoformat timestamp of the current UTC clock of the system'},
                     operation_description="Get the current system time in UTC")
@api_view(['GET'])
def utc(request):
    return HttpResponse(datetime.utcnow().isoformat(), content_type='text/plain')

@permission_classes([AllowAny])
@authentication_classes([AllowAny])
@swagger_auto_schema(method='GET',
                     responses={200: 'The LST time in hms format at the given UTC time and station or longitude'},
                     operation_description="Get LST time for UTC time and station or longitude",
                     manual_parameters=[Parameter(name='station', required=False, type='string', in_='query',
                                                  description="A station names (defaults to CS002)"),
                                        Parameter(name='timestamp', required=False, type='string', in_='query',
                                                  description="A timestamp in isoformat (defaults to utcnow)"),
                                        Parameter(name='longitude', required=False, type='string', in_='query',
                                                  description="A longitude as float")
                                        ])
@api_view(['GET'])
def lst(request):
    # Handling optional parameters via django paths in urls.py is a pain, we access them on the request directly instead.
    timestamp = request.GET.get('timestamp', None)
    station = request.GET.get('station', None)
    longitude = request.GET.get('longitude', None)

    # conversions
    if timestamp:
        timestamp = dateutil.parser.parse(timestamp)  #  isot to datetime
    if longitude:
        longitude = float(longitude)

    if station:
        lst_lon = local_sidereal_time_for_utc_and_station(timestamp, station)
    elif longitude:
        lst_lon = local_sidereal_time_for_utc_and_longitude(timestamp, longitude)
    else:
        # fall back to defaults
        lst_lon = local_sidereal_time_for_utc_and_station(timestamp)

    # todo: do we want to return a dict, so users can make sure their parameters were parsed correctly instead?
    return HttpResponse(str(lst_lon), content_type='text/plain')


@permission_classes([AllowAny])
@authentication_classes([AllowAny])
@swagger_auto_schema(method='GET',
                     responses={200: 'A JSON object with sunrise, sunset, day and night of the given stations at the given timestamps'},
                     operation_description="Get sunrise, sunset, day and night for stations and timestamps.\n\n"
                                           "Example request: /api/util/sun_rise_and_set?stations=CS002,CS005&timestamps=2020-05-01,2020-09-09T11-11-00",
                     manual_parameters=[Parameter(name='stations', required=False, type='string', in_='query',
                                                  description="comma-separated list of station names"),
                                        Parameter(name='timestamps', required=False, type='string', in_='query',
                                                  description="comma-separated list of isoformat timestamps")])
@api_view(['GET'])
def get_sun_rise_and_set(request):
    """
    returns sunrise and sunset at the given stations and timestamps, or today at LOFAR core if none specified.
    example request: /api/util/sun_rise_and_set?stations=CS002,CS005&timestamps=2020-05-01,2020-09-09T11-11-00
    """
    timestamps = request.GET.get('timestamps', None)
    stations = request.GET.get('stations', None)
    if timestamps is None:
        timestamps = [datetime.utcnow()]
    else:
        timestamps = timestamps.split(',')
        timestamps = [dateutil.parser.parse(timestamp) for timestamp in timestamps]  #  isot to datetime
    if stations is None:
        stations = ["CS002"]
    else:
        stations = stations.split(',')

    return JsonResponse(timestamps_and_stations_to_sun_rise_and_set(timestamps, stations))