import datetime
import html
import json
from typing import Any

from .user import User


class Analytics:
    def __init__(self):
        self.issued_at = datetime.datetime.now()
        self.users = 0
        self.groups: dict[str, int] = {}

    def add(self, user: User) -> None:
        self.users += 1
        if not user.active_target or user.active_target["kind"] != "group":
            return
        group = user.active_target["name"]
        self.groups[group] = self.groups.get(group, 0) + 1

    def toDict(self) -> dict[str, Any]:
        return {
            "version": 3,
            "issued_at": self.issued_at.isoformat(),
            "users": self.users,
            "groups": dict(sorted(self.groups.items())),
        }

    def append(self) -> None:
        try:
            with open("./web/analytics/data-v2.json", "r", encoding="utf-8") as file:
                history: list[dict[str, Any]] = json.load(file)
        except (FileNotFoundError, json.JSONDecodeError, OSError):
            history = []

        history.append(self.toDict())
        with open("./web/analytics/data-v2.json", "w", encoding="utf-8") as file:
            json.dump(history[-30:], file, ensure_ascii=False)

    def text(self) -> str:
        group_lines = [
            f"{html.escape(group)}: <code>{count}</code>"
            for group, count in sorted(self.groups.items())
        ]
        groups = "\n".join(group_lines) if group_lines else "Нет зарегистрированных групп"
        return (
            f'<b>Аналитика за {self.issued_at.strftime("%d.%m")} 📊</b>\n'
            f"Пользователи: <code>{self.users}</code>\n\n"
            f"<b>Группы</b>\n{groups}"
        )