FunguyBot/plugins/welcome.py

"""
Plugin for welcoming new users to the room.

Features:
  * Automatically greets users when they first join the target room.
  * !welcome command – manually trigger the welcome message for yourself.
  * Per-user cooldown to prevent welcome spam on repeated part/join cycles.

Restricted to room: !NXdVjDXPxXowPkrJJY:matrix.org
"""

import logging
import time
import simplematrixbotlib as botlib
import nio

# ---------------------------------------------------------------------------
# Configuration
# ---------------------------------------------------------------------------

ALLOWED_ROOM_ID = "!NXdVjDXPxXowPkrJJY:matrix.org"

# How many seconds must pass before a user can receive another auto-welcome.
# Default: 10 minutes. Raise this if you still see abuse.
WELCOME_COOLDOWN_SECONDS = 600

# ---------------------------------------------------------------------------
# Cooldown state
# Maps Matrix user ID → monotonic timestamp of last auto-welcome sent.
# Resets on bot restart, which is fine — a fresh start is a clean slate.
# ---------------------------------------------------------------------------

_last_welcomed: dict[str, float] = {}


def _is_on_cooldown(user_id: str) -> bool:
    """Return True if the user was welcomed recently and should be skipped."""
    last = _last_welcomed.get(user_id)
    if last is None:
        return False
    return (time.monotonic() - last) < WELCOME_COOLDOWN_SECONDS


def _record_welcome(user_id: str) -> None:
    """Mark that this user was just welcomed."""
    _last_welcomed[user_id] = time.monotonic()


# ---------------------------------------------------------------------------
# Internal helpers
# ---------------------------------------------------------------------------

def _build_welcome_message(display_name: str) -> str:
    """Return the Markdown welcome message for a given display name."""
    return f"Hey **{display_name}**, welcome in — so glad to have you here! 🎉 Feel free to tell us a bit about what you're into (self‑hosting, security, homelabs, programming… or just lurk and say hi whenever 🍄)"


# ---------------------------------------------------------------------------
# Plugin setup - called by funguy.py's run() after the bot object is created
# ---------------------------------------------------------------------------

def setup(bot):
    """
    Register the member-join listener.

    funguy.py must call plugin_module.setup(self.bot) for each loaded plugin
    (after self.bot is created) for this listener to fire.
    """

    @bot.listener.on_custom_event(nio.RoomMemberEvent)
    async def _on_member_event(room, event):
        logging.debug(
            "RoomMemberEvent received: room=%s, sender=%s, membership=%s",
            room.room_id, event.sender, event.membership,
        )

        # Only the configured room
        if room.room_id != ALLOWED_ROOM_ID:
            return

        # Only on actual join (not invite / leave / ban)
        if event.membership != "join":
            return

        # Ignore the bot itself
        if event.sender == bot.async_client.user_id:
            logging.debug("Ignoring bot's own join event")
            return

        # Check if this is a genuine first join by looking for previous membership
        is_first_join = True

        # Check prev_content directly on the event
        if hasattr(event, 'prev_content') and event.prev_content:
            prev_membership = event.prev_content.get('membership')
            if prev_membership is not None:
                is_first_join = False
                logging.debug(f"User {event.sender} had previous membership '{prev_membership}' in prev_content")

        # Check unsigned field (some events store prev_content there)
        if is_first_join and hasattr(event, 'unsigned') and event.unsigned:
            prev_content = event.unsigned.get('prev_content', {})
            prev_membership = prev_content.get('membership')
            if prev_membership is not None:
                is_first_join = False
                logging.debug(f"User {event.sender} had previous membership '{prev_membership}' in unsigned")

        if not is_first_join:
            logging.info(f"Skipping welcome for {event.sender} - not a first join (name change or rejoin)")
            return

        # --- Cooldown check ---
        if _is_on_cooldown(event.sender):
            remaining = WELCOME_COOLDOWN_SECONDS - (
                time.monotonic() - _last_welcomed[event.sender]
            )
            logging.info(
                "Skipping welcome for %s – cooldown active (%.0fs remaining)",
                event.sender, remaining,
            )
            return

        # Derive a friendly display name from the Matrix ID (@name:server → name)
        display_name = event.sender.split(":")[0].lstrip("@")

        logging.info(
            "User %s joined room %s – sending welcome", event.sender, room.room_id
        )
        try:
            await bot.api.send_markdown_message(
                room.room_id, _build_welcome_message(display_name)
            )
            _record_welcome(event.sender)  # Only recorded after a successful send
            logging.info("Welcome message sent successfully to %s", display_name)
        except Exception as exc:
            logging.error("Failed to send welcome message: %s", exc)

    logging.info("Join listener registered for room %s", ALLOWED_ROOM_ID)


# ---------------------------------------------------------------------------
# Plugin entry point - called by FunguyBot for every message event
# ---------------------------------------------------------------------------

async def handle_command(room, message, bot, prefix, config):
    """Handle the !welcome command (not subject to the auto-welcome cooldown)."""

    match = botlib.MessageMatch(room, message, bot, prefix)

    if not (
        match.is_not_from_this_bot()
        and match.prefix()
        and match.command("welcome")
    ):
        return

    if room.room_id != ALLOWED_ROOM_ID:
        await bot.api.send_text_message(
            room.room_id,
            "The !welcome command only works in the designated room.",
        )
        return

    sender = str(message.sender)
    display_name = sender.split(":")[0].lstrip("@")

    await bot.api.send_markdown_message(
        room.room_id, _build_welcome_message(display_name)
    )
    logging.info("Sent manual !welcome to %s", sender)