#    Society Self-Service
#    Copyright © 2018-2019  Yingtong Li (RunasSudo)
#
#    This program is free software: you can redistribute it and/or modify
#    it under the terms of the GNU Affero General Public License as published by
#    the Free Software Foundation, either version 3 of the License, or
#    (at your option) any later version.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU Affero General Public License for more details.
#
#    You should have received a copy of the GNU Affero General Public License
#    along with this program.  If not, see <https://www.gnu.org/licenses/>.

from googleapiclient.discovery import build

from django.conf import settings
from django.utils import timezone

from . import models

import datetime

def get_calendar_events(calbegin, calend):
	service = build('calendar', 'v3', developerKey=settings.GOOGLE_API_KEY)
	events = service.events().list(
		calendarId=settings.GOOGLE_CALENDAR_ID,
		orderBy='startTime',
		singleEvents=True,
		timeMin=datetime.datetime.combine(calbegin, datetime.time(tzinfo=timezone.get_current_timezone())).isoformat(),
		timeMax=datetime.datetime.combine(calend, datetime.time(tzinfo=timezone.get_current_timezone())).isoformat()
	).execute()
	for event in events['items']:
		yield {
			'date': datetime.datetime.strptime(event['start']['date'], '%Y-%m-%d') if 'date' in event['start'] else datetime.datetime.strptime(event['start']['dateTime'][:-3] + event['start']['dateTime'][-2:], '%Y-%m-%dT%H:%M:%S%z'),
			'title': event['summary'],
			'link': event['htmlLink']
		}

def bulletin_dates(dt):
	calbegin = dt.date() + datetime.timedelta(days=1) # Start tomorrow for calendar
	calend = calbegin + datetime.timedelta(days=14)
	
	bulbegin = dt.date()
	bulend = bulbegin + datetime.timedelta(days=7)
	
	return calbegin, calend, bulbegin, bulend

def bulletin_args(member, groups, events, bulbegin, bulend):
	groups_data = []
	for group in groups:
		items = []
		for item in group.bulletinitem_set.filter(date__gte=bulbegin).filter(date__lt=bulend).all():
			# Check also_limit
			if member is None or len(item.also_limit) == 0 or any(any(g.id == x for g in groups) for x in item.also_limit):
				items.append(item)
		
		if len(items) > 0:
			groups_data.append({
				'group': group,
				'name': group.name,
				'bulletin_items': items
			})
	
	more = []
	all_groups = models.Group.objects.all()
	for group in all_groups:
		if group in groups:
			continue
		if not group.subscribable:
			continue
		
		for item in group.bulletinitem_set.filter(date__gte=bulbegin).filter(date__lt=bulend).all():
			# Check also_limit
			# Allow matching across all groups, but only subscribable ones
			if member is None or len(item.also_limit) == 0 or any(any(g.id == x and g.subscribable for g in all_groups) for x in item.also_limit):
				more.append(item)
		
		if len(more) >= 3:
			break
	
	return {
		'member': member,
		'events': events,
		'groups': groups_data,
		'more': more,
		'bulbegin': bulbegin,
		'bulend': bulend
	}