#!/usr/bin/env python3
"""
Session interface middlewares to integrate the aiohttp app with Buckler.
"""
import json
from datetime import datetime

import aiohttp
from aiohttp import web

import config

@web.middleware
async def buckler_session(request, handler):
	"""
	Verifies the user with the configured Buckler app and retrieves any
	session data they may have. Redirects them to the login page otherwise.
	"""
	user_id = request.cookies.get('userid')
	user_sid = request.cookies.get('session')

	url = config.buckler['url'] + '/get_session'
	params = {
		'app_id': config.buckler['app_id'],
		'app_key': config.buckler['app_key'],
		'userid': user_id,
		'session': user_sid
	}
	async with aiohttp.ClientSession() as session:
		async with session.get(url, params=params) as resp:
			data = await resp.json()
			if data.get('error'):
				raise web.HTTPFound(location=config.buckler['login_url'])
			request['session'] = data['session_data']
			request['meta'] = data['meta']

		resp = await handler(request)

		if request['session'] != data['session_data']: # session data modified
			url = config.buckler['url'] + '/set_session'
			data = json.dumps(request['session'])
			session.post(url, params=params, data=data) # TODO: error handle?

		last_used = datetime.fromisoformat(request['meta']['last_used'])
		now = datetime.now(last_used.tzinfo)
		delta = now - last_used
		if delta.seconds > 600:
			resp.set_cookie(
				'userid',
				user_id,
				max_age=30*24*60*60,
				secure=True,
				httponly=True)
			resp.set_cookie(
				'session',
				user_sid,
				max_age=30*24*60*60,
				secure=True,
				httponly=True)

	return resp