#!/usr/bin/env python3


import time

from diaspy.models import Notification


"""This module abstracts notifications.
"""


class Notifications():
	"""This class represents notifications of a user.
	"""
	def __init__(self, connection):
		self._connection = connection
		self._data = {}
		self._notifications = self.get()
		self.page = 1

	def __len__(self):
		return len(self._notifications)

	def __iter__(self):
		return iter(self._notifications)

	def __getitem__(self, n):
		return self._notifications[n]

	def _finalise(self, notifications):
		self._data['unread_count'] = notifications['unread_count']
		self._data['unread_count_by_type'] = notifications['unread_count_by_type']
		return [Notification(self._connection, n) for n in notifications.get('notification_list', [])]

	def last(self):
		"""Returns list of most recent notifications.
		"""
		params = {'per_page': 5, '_': int(round(time.time(), 3)*1000)}
		headers = {'x-csrf-token': repr(self._connection)}

		request = self._connection.get('notifications.json', headers=headers, params=params)

		if request.status_code != 200:
			raise Exception('status code: {0}: cannot retrieve notifications'.format(request.status_code))
		return self._finalise(request.json())

	def _expand(self, new_notifications):
		ids = [notification.id for notification in self._notifications]
		notifications = self._notifications
		data = self._data
		for n in new_notifications:
			if n.id not in ids:
				if n.unread:
					data['unread_count'] +=1
					data['unread_count_by_type'][n.type] +=1
				notifications.append(n)
				ids.append(n.id)
		self._notifications = notifications
		self._data = data

	def _update(self, new_notifications):
		ids = [notification.id for notification in self._notifications]
		notifications = self._notifications
		data = self._data

		update = False
		if new_notifications[len(new_notifications)-1].id not in ids:
			update = True

		for i in range(len(new_notifications)):
			if new_notifications[-i].id not in ids:
				if new_notifications[-i].unread:
					data['unread_count'] +=1
					data['unread_count_by_type'][new_notifications[-i].type] +=1
				notifications = [new_notifications[-i]] + notifications
				ids.append(new_notifications[-i].id)
		self._notifications = notifications
		self._data = data
		if update: self.update() # if there is a gap

	def update(self, per_page=5, page=1):
		result = self.get(per_page=per_page, page=page)
		if result: self._update( result )

	def more(self, per_page=5, page=0):
		if not page: page = self.page + 1
		self.page = page
		result = self.get(per_page=per_page, page=page)
		if result:
			self._expand( result )

	def get(self, per_page=5, page=1):
		"""Returns list of notifications.
		"""
		params = {'per_page': per_page, 'page': page}
		headers = {'x-csrf-token': repr(self._connection)}

		request = self._connection.get('notifications.json', headers=headers, params=params)

		if request.status_code != 200:
			raise Exception('status code: {0}: cannot retreive notifications'.format(request.status_code))
		return self._finalise(request.json())