#-*- coding: utf-8 -*-

import logging
from sqlite3 import IntegrityError
from typing import List, Literal

from apprise import Apprise

from backend.custom_exceptions import (NotificationServiceNotFound,
                                       ReminderNotFound)
from backend.db import get_db

filter_function = lambda query, p: (
	query in p["title"].lower()
	or query in p["text"].lower()
)

class StaticReminder:
	"""Represents a static reminder
	"""
	def __init__(self, user_id: int, reminder_id: int) -> None:
		self.id = reminder_id
		
		# Check if reminder exists
		if not get_db().execute(
			"SELECT 1 FROM static_reminders WHERE id = ? AND user_id = ? LIMIT 1;",
			(self.id, user_id)
		).fetchone():
			raise ReminderNotFound
		
	def get(self) -> dict:
		"""Get info about the static reminder

		Returns:
			dict: The info about the reminder
		"""
		reminder = get_db(dict).execute("""
			SELECT
				id,
				title, text,
				color
			FROM static_reminders
			WHERE id = ?
			LIMIT 1;
			""",
			(self.id,)
		).fetchone()
		reminder = dict(reminder)
		
		reminder['notification_services'] = list(map(lambda r: r[0], get_db().execute("""
			SELECT notification_service_id
			FROM reminder_services
			WHERE static_reminder_id = ?;
		""", (self.id,))))

		return reminder
	
	def update(
		self,
		title: str = None,
		notification_services: List[int] = None,
		text: str = None,
		color: str = None
	) -> dict:
		"""Edit the static reminder

		Args:
			title (str, optional): The new title of the entry. Defaults to None.
			notification_services (List[int], optional): The new id's of the notification services to use to send the reminder. Defaults to None.
			text (str, optional): The new body of the reminder. Defaults to None.
			color (str, optional): The new hex code of the color of the reminder, which is shown in the web-ui. Defaults to None.

		Raises:
			NotificationServiceNotFound: One of the notification services was not found

		Returns:
			dict: The new static reminder info
		"""
		logging.info(
			f'Updating static reminder {self.id}: '
			+ f'{title=}, {notification_services=}, {text=}, {color=}'
		)

		# Get current data and update it with new values
		data = self.get()
		new_values = {
			'title': title,
			'text': text,
			'color': color
		}
		for k, v in new_values.items():
			if k == 'color' or v is not None:
				data[k] = v
				
		# Update database
		cursor = get_db()
		cursor.execute("""
			UPDATE static_reminders
			SET
				title = ?, text = ?,
				color = ?
			WHERE id = ?;
			""",
			(data['title'], data['text'],
			data['color'],
			self.id)
		)
		
		if notification_services:
			cursor.connection.isolation_level = None
			cursor.execute("BEGIN TRANSACTION;")
			cursor.execute("DELETE FROM reminder_services WHERE static_reminder_id = ?", (self.id,))
			try:
				cursor.executemany(
					"INSERT INTO reminder_services(static_reminder_id, notification_service_id) VALUES (?,?)",
					((self.id, s) for s in notification_services)
				)
				cursor.execute("COMMIT;")
			except IntegrityError:
				raise NotificationServiceNotFound
			cursor.connection.isolation_level = ""

		return self.get()

	def delete(self) -> None:
		"""Delete the static reminder
		"""
		logging.info(f'Deleting static reminder {self.id}')
		get_db().execute("DELETE FROM static_reminders WHERE id = ?", (self.id,))
		return

class StaticReminders:
	"""Represents the static reminder library of the user account
	"""
	sort_functions = {
		'title': (lambda r: (r['title'], r['text'], r['color']), False),
		'title_reversed': (lambda r: (r['title'], r['text'], r['color']), True),
		'date_added': (lambda r: r['id'], False),
		'date_added_reversed': (lambda r: r['id'], True)
	}

	def __init__(self, user_id: int) -> None:
		self.user_id = user_id
		
	def fetchall(self, sort_by: Literal["title", "title_reversed", "date_added", "date_added_reversed"] = "title") -> List[dict]:
		"""Get all static reminders

		Args:
			sort_by (Literal["title", "title_reversed", "date_added", "date_added_reversed"], optional): How to sort the result. Defaults to "title".

		Returns:
			List[dict]: The id, title, text and color of each static reminder
		"""
		sort_function = self.sort_functions.get(
			sort_by,
			self.sort_functions['title']
		)

		reminders: list = list(map(
			dict,
			get_db(dict).execute("""
				SELECT
					id,
					title, text,
					color
				FROM static_reminders
				WHERE user_id = ?
				ORDER BY title, id;
				""",
				(self.user_id,)
			)
		))
		
		# Sort result
		reminders.sort(key=sort_function[0], reverse=sort_function[1])

		return reminders

	def search(self, query: str, sort_by: Literal["title", "title_reversed", "date_added", "date_added_reversed"] = "title") -> List[dict]:
		"""Search for static reminders

		Args:
			query (str): The term to search for
			sort_by (Literal["title", "title_reversed", "date_added", "date_added_reversed"], optional): How to sort the result. Defaults to "title".

		Returns:
			List[dict]: All static reminders that match. Similar output to self.fetchall
		"""		
		query = query.lower()
		reminders = list(filter(
			lambda p: filter_function(query, p),
			self.fetchall(sort_by)
		))
		return reminders

	def fetchone(self, id: int) -> StaticReminder:
		"""Get one static reminder

		Args:
			id (int): The id of the static reminder to fetch

		Returns:
			StaticReminder: A StaticReminder instance
		"""
		return StaticReminder(self.user_id, id)
	
	def add(
		self,
		title: str,
		notification_services: List[int],
		text: str = '',
		color: str = None
	) -> StaticReminder:
		"""Add a static reminder

		Args:
			title (str): The title of the entry
			notification_services (List[int]): The id's of the notification services to use to send the reminder.
			text (str, optional): The body of the reminder. Defaults to ''.
			color (str, optional): The hex code of the color of the reminder, which is shown in the web-ui. Defaults to None.

		Raises:
			NotificationServiceNotFound: One of the notification services was not found

		Returns:
			StaticReminder: A StaticReminder instance representing the newly created static reminder
		"""
		logging.info(
			f'Adding static reminder with {title=}, {notification_services=}, {text=}, {color=}'
		)

		cursor = get_db()
		id = cursor.execute("""
			INSERT INTO static_reminders(user_id, title, text, color)
			VALUES (?,?,?,?);
			""",
			(self.user_id, title, text, color)
		).lastrowid
		
		try:
			cursor.executemany(
				"INSERT INTO reminder_services(static_reminder_id, notification_service_id) VALUES (?, ?);",
				((id, service) for service in notification_services)
			)
		except IntegrityError:
			raise NotificationServiceNotFound
		
		return self.fetchone(id)

	def trigger_reminder(self, id: int) -> None:
		"""Trigger a static reminder to send it's reminder

		Args:
			id (int): The id of the static reminder to trigger

		Raises:
			ReminderNotFound: The static reminder with the given id was not found
		"""
		logging.info(f'Triggering static reminder {self.id}')
		cursor = get_db(dict)
		reminder = cursor.execute("""
			SELECT title, text
			FROM static_reminders
			WHERE
				id = ?
				AND user_id = ?
			LIMIT 1;
		""", (id, self.user_id)).fetchone()
		if not reminder:
			raise ReminderNotFound
		reminder = dict(reminder)

		a = Apprise()
		cursor.execute("""
			SELECT url
			FROM reminder_services rs
			INNER JOIN notification_services ns
			ON rs.notification_service_id = ns.id
			WHERE rs.static_reminder_id = ?;
		""", (id,))
		for url in cursor:
			a.add(url['url'])
		a.notify(title=reminder['title'], body=reminder['text'])
		return