#!/usr/bin/env python3

import sys
import re
import json


try:
	USERS = __import__("users").users()
except ImportError:
	USERS = None

NUMBER_EMOJI = {
	"zero": "0",
	"one": "1",
	"two": "2",
	"three": "3",
	"four": "4",
	"five": "5",
	"six": "6",
	"seven": "7",
	"eight": "8",
	"nine": "9",
}

URL_PREFIX = "https://mattermost.zeus.gent/zeus/pl/"

second_last_number = None
second_last_line = {"id": None}
last_number = None
last_line = {"id": None}
messages = []
start_number = None
for line in sys.stdin:
	line = json.loads(line)
	# Ignore non-message posts (e.g. join/leave)
	if line.get("type") is not None:
		continue

	if "user_id" in line and USERS is not None:
		line["username"] = USERS.get(line["user_id"])
	if "username" in line:
		line["mention"] = f" (@{line['username']})"
	else:
		line["mention"] = ""

	if "message" in line and line["message"] != "":
		message = line["message"]
		message = re.sub(r"^[#>]* ?|[*_`]*", "", message)
		for emoji, numb in NUMBER_EMOJI.items():
			message = re.sub(f" *:{emoji}: *", numb, message)
		message = re.sub(" ?:(?:green)?num([0-9]+): ?", lambda m: m.group(1), message)
		message = message.replace("\ufe0f", "").replace("\u20e3", "")
		message = message.strip()
	else:
		try:
			message = line["metadata"]["files"][0]["name"].split(".")[0]
		except (KeyError, IndexError):
			messages.append(
				f"- [Unrecognized post]({URL_PREFIX}{line['id']}){line['mention']}"
			)
			continue

	if line.get("edit_at") is not None:
		messages.append(
			f"- Edited message [{message}]({URL_PREFIX}{line['id']}){line['mention']}"
		)

	m = re.fullmatch(r"-?[1-9][0-9]*|0", message)
	if not m:
		messages.append(
			f"- Non-number message [{message}]({URL_PREFIX}{line['id']}){line['mention']}"
		)
	else:
		number = int(m.group(0))
		if last_number is None:
			start_number = number
			last_number = number - 1
			second_last_number = number - 2

		if number != last_number + 1:
			if number == second_last_number + 2 and last_number != second_last_number + 1:
				messages.pop()
				messages.append(
					f"- [{last_number}]({URL_PREFIX}{last_line['id']}) should have been {number - 1}{last_line['mention']}"
				)
			elif number == last_number:
				messages.append(
					f"- Duplicate [{number}]({URL_PREFIX}{line['id']}){line['mention']}"
				)
			elif number == second_last_number + 1 and last_number != second_last_number + 1:
				messages.pop()
				messages.append(
					f"- Stray [{last_number}]({URL_PREFIX}{last_line['id']}){last_line['mention']}"
				)
			elif number == last_number + 2:
				messages.append(
					f"- Skipped [{last_number + 1}]({URL_PREFIX}{line['id']}){line['mention']}"
				)
			else:
				messages.append(
					f"- Going from [{last_number}]({URL_PREFIX}{last_line['id']}) "
					f"to [{number}]({URL_PREFIX}{line['id']}){line['mention']}"
				)

		second_last_number = last_number
		second_last_line = last_line
		last_number = number
		last_line = line

if start_number is None and messages == []:
	print("No input data")
else:
	if start_number is None:
		print("No valid number messages!")
	else:
		print(f"Checked from {start_number} up to {number}")
	if messages:
		print("🚨 Errors: 🚨")
		print("\n".join(messages))
	else:
		print("No errors! 🎉")