#!/usr/bin/env -S python3
from __future__ import annotations  # PEP 585 for Python 3.7 and 3.8
import logging
import requests
import time
import typing
import urllib.parse


ATW="https://wiki.archiveteam.org/"
ATAPI = ATW + "api.php"

def get_new(newestRc: typing.Optional[tuple[str, int]]) -> tuple[list[dict], tuple[str, int]]:
	'''
	Fetches edits made after newestRc = (newestTimestamp, newestRcId), which shall both refer to the last change already known/processed.
	newestTimestamp is a timestamp in YYYY-MM-DDTHH:MM:SSZ format; newestRcId is the internal ID of the change.
	The return value are the list of changes after newestRcId in chronological order (as returned by MW), and a new (newestTimestamp, newestRcId) tuple.
	If newestRc is None, this returns an empty list of changes and the timestamp and rev ID of the most recent edit (for initialisation of a feed).
	'''

	logging.info(f'Fetching with newestRc = {newestRc!r}')
	if newestRc is None:
		newestTimestamp, newestRcId = None, None
	else:
		newestTimestamp, newestRcId = newestRc
	rcend = f'&rcend={newestTimestamp}' if newestTimestamp else ''
	r = requests.get(f'{ATAPI}?action=query&list=recentchanges&rcdir=older&format=json&rcprop=user|comment|timestamp|sizes|title|flags|ids|loginfo&continue=&rclimit=500{rcend}',
	                 timeout = 5,
	                )
	r.raise_for_status()
	o = r.json()
	if not o['query']['recentchanges']:
		return [], (newestTimestamp, newestRcId)
	rc = o['query']['recentchanges']
	changes = []
	if newestRcId is not None:
		for c in rc:
			if c['rcid'] <= newestRcId:
				break
			changes.append(c)
	return changes[::-1], (rc[0]['timestamp'], rc[0]['rcid'])


def truncate(s: str, limit: int) -> str:
	'''If s is longer than limit, split on words and return a truncated version no longer than limit.'''
	if len(s) <= limit:
		return s
	words = s.split(' ')
	trunLength = 0
	trun = []
	while words and trunLength + 1 + len(words[0]) < limit - 1:
		word = words.pop(0)
		trunLength += 1 + len(word)
		trun.append(word)
	return f'{" ".join(trun)}…'


def format_change(change: dict) -> typing.Optional[str]:
	'''Formats a change for posting to IRC. Returns None if it's an event that isn't handled and not to be reported to IRC.'''
	title = change['title']
	urlSafeTitle = urllib.parse.quote(change['title'])
	url = None
	if change['type'] == 'new':
		verb = 'created'
		url = f'{ATW}?title={urlSafeTitle}&oldid={change["revid"]}'
	elif change['type'] == 'edit':
		verb = 'edited'
		url = f'{ATW}?title={urlSafeTitle}&diff={change["revid"]}&oldid={change["old_revid"]}'
	elif change['type'] == 'log' and change['logtype'] == 'delete':
		verb = 'deleted'
		url = ''
	elif change['type'] == 'log' and change['logtype'] == 'move':
		verb = 'moved'
		title = f'{change["logparams"]["target_title"]} (from {change["title"]})'
		url = f'{ATW}?title={urllib.parse.quote(change["logparams"]["target_title"])}'
	else:
		return
	comment = change["comment"] if change["comment"] else ''
	url = f'{url}' if url else ''
	return f'AT Wiki | {title} was {verb} by {change["user"]} at {change["timestamp"]} | {comment} | {url}'


def main():
	# Get initial TS/rcid tuple
	_, newestRc = get_new(None)
	time.sleep(60)
	while True:
		try:
			changes, newestRc = get_new(newestRc)
		except Exception as e:
			logging.error('get_new failed', exc_info = e)
			time.sleep(60)
			continue
		for change in changes:
			formatted = format_change(change)
			if formatted:
				print(formatted, flush = True)
			else:
				logging.warning(f'Suppressed change because it was un- or ill-formatted: {change!r}')
		time.sleep(60)


if __name__ == '__main__':
	logging.basicConfig(
		format = '{asctime}.{msecs:03.0f}  {levelname}  {name}  {message}',
		datefmt = '%Y-%m-%d %H:%M:%S',
		style = '{',
		level = logging.INFO,
	)
	main()