import atexit
import json
from datetime import datetime
from slugify import slugify

from .config import Config
config = Config()
SPACES = int(config['json_indent']) if config['json_indent'] else None


from tinydb import TinyDB, Query, operations
dbfile = config['db_file'] or '/tmp/ftracker-db.json'
db = TinyDB(dbfile, indent=SPACES)


from flask import Flask, request, redirect
app = Flask(__name__, static_folder='../web')


def shutdown():
	print('\rReceived stop signal, stopping threads...')
	db.close()

atexit.register(shutdown)


@app.route('/guidelines')
def get_guidelines():
	dest = config['guideline_url'] or None
	if dest:
		return redirect(dest)
	return "No guideline document was configured.", 404


@app.route('/checkin', methods=['POST'])
def post_arrival():

	try:
		payload = request.data.decode('UTF-8')
		data = json.loads(payload)
	except ValueError as e:
		return 'Error: JSON decode error:\n' + str(e), 400

	if not ('checkpoint' in data and 'name' in data):
		return "Error: Key missing. See docs/API.md for reference.", 400

	name = slugify(data['name'])
	checkpoint = slugify(data['checkpoint'])

	now = datetime.utcnow().isoformat() + 'Z'
	db.insert({
		'name': name,
		'checkpoint': checkpoint,
		'arrival': now,
	})

	return 'OK', 200


@app.route('/data')
def get_data():

	if not 'Authorization' in request.headers:
		return 'Error: No Authorization', 401, {'WWW-Authenticate': 'Basic'}

	if request.authorization.username != config['admin_user']:
		return "Wrong username", 403

	if request.authorization.password != config['admin_pass']:
		return "Wrong password", 403

	start = request.args.get('start', default = None, type = str)
	end   = request.args.get('end'  , default = None, type = str)
	room  = request.args.get('room' , default = None, type = str)

	# Skip DB query if no parameters given
	# (Which is currently every request)
	if not (start or end or room):
		return json.dumps(db.all(), indent=SPACES), 200

	def is_after(val, iso):
		return (val >= iso if val else True ) if iso else True

	def is_before(val, iso):
		return (val <= iso if val else False) if iso else True

	Entry = Query()
	r = db.search(
		(Entry.departure.test(is_after, start)) &
		(Entry.arrival.test(is_before, end)) &
		(Entry.room.search(room or ".*"))
	)

	return json.dumps(r, indent=SPACES), 200