signal-bot/signal_bot/bot.py

# Copyright (c) 2026 Krzysztof Rudnicki. MIT licence.
"""The bot object itself: the command wiring and the two loops it owns.

Split out of app.py, which had grown to the 250-line cap with the ASGI
entrypoint, the object graph and the startup sequence all in one file. This
half is "what the bot does"; startup.py is "how it comes up".
"""

from __future__ import annotations

import datetime as dt
import logging
from collections.abc import Callable
from dataclasses import dataclass
from typing import TYPE_CHECKING

from signal_bot.animals import load_aliases, register_animal_commands
from signal_bot.announce import announce_all
from signal_bot.changelog import load as load_changelog
from signal_bot.decorators import cooldown
from signal_bot.dispatcher import Dispatcher
from signal_bot.help_command import register_help_command
from signal_bot.http_client import ImageFetcher
from signal_bot.media_strip import ExiftoolStripper
from signal_bot.pack_add import register_add_command
from signal_bot.pack_command import register_pack_commands
from signal_bot.pack_holder import PackHolder
from signal_bot.pack_load import load as load_pack
from signal_bot.pack_random import register_random_command
from signal_bot.popes_command import register_pope_command
from signal_bot.portraits import PortraitCache
from signal_bot.registry import CommandRegistry
from signal_bot.reporting import compose
from signal_bot.stats import periods
from signal_bot.stats.commands import register_stats_commands
from signal_bot.stats.nightly import days_to_report, mark_reported
from signal_bot.versioning import POPE

if TYPE_CHECKING:
    from pathlib import Path

    import httpx

    from signal_bot.config import Config
    from signal_bot.decorators import Decorator
    from signal_bot.discovery import GroupDirectory
    from signal_bot.liveness import Liveness
    from signal_bot.store import Store
    from signal_bot.transport_base import Transport

logger = logging.getLogger(__name__)

Clock = Callable[[], dt.datetime]

COOLDOWN_MESSAGE = "BEEP BOOP POCZEKAJ {seconds} {unit}."


def now_local() -> dt.datetime:
    """Current Warsaw time -- the group's day, not the host's.

    One definition of "day" for the whole bot. The daily scheduler fires
    against this, ``CommandContext.day`` keys the daily limits off it, and
    every event is filed under it, so a host in another timezone (or a
    container on UTC) cannot make those three disagree.
    """
    return periods.now()


@dataclass
class Bot:
    """The wired-up bot and its two long-running loops."""

    config: Config
    store: Store
    transport: Transport
    directory: GroupDirectory
    dispatcher: Dispatcher
    liveness: Liveness
    # The same cache !papiez draws from, so a release announcement and the
    # command never download the same portrait twice.
    portraits: PortraitCache
    # The same clock the dispatcher files events against. One clock, so
    # "which day is it" cannot differ between writing an event and reporting
    # on it -- which is precisely the drift the old reset-after-post had.
    clock: Clock = now_local

    async def publish_report(self) -> None:
        """Post each group **one** message: today, plus anything still owed.

        Today, because 21:37 is when the group expects to read its own
        numbers; a post at 21:37 about yesterday is a day late to everyone
        looking at it. The count therefore closes at the report time and the
        rest of the evening lands in tomorrow's day -- render_day says so,
        because a total that quietly omits three hours is worse than one that
        admits to it.

        One message, always. A run can have several things to say -- a day
        the bot was down for, the day it is on now, and the week or month
        that ended inside them -- and saying each in its own post turns one
        evening into four notifications. They are blocks in one message
        instead, which is also what makes the send atomic: either the group
        got the lot, or nothing is marked and the next run says it all again.

        Nothing is deleted afterwards. Each group is isolated on purpose: one
        group refusing the report -- the bot removed from it, a transient send
        failure -- must not cost every other group its report.
        """
        latest = periods.today(self.clock())
        for group_id in self.directory.groups:
            await self._report_group(group_id, latest)

    async def _report_group(self, group_id: str, latest: str) -> None:
        """Say everything one group is owed, in one message or not at all."""
        days = days_to_report(self.store, group_id, latest)
        if not days:
            return
        now = self.clock()
        text = compose(
            self.store,
            self.directory,
            group_id,
            days,
            today=periods.today(now),
            # Off the clock rather than off REPORT_HOUR: the scheduled run
            # fires at the configured minute and so says exactly that, while
            # a run started by hand at some other hour tells the truth
            # instead of repeating a time nobody waited for.
            closed_at=now.strftime("%H:%M"),
        )
        if text:
            try:
                await self.transport.send_text(text, group_id)
            except Exception:
                # Nothing is marked, so the next run repeats the whole thing
                # rather than losing the days that were inside this message.
                logger.exception("report failed for group %s", group_id)
                return
        # Marked even when there was nothing to say: a day nobody spoke on is
        # settled, not pending, and leaving it unmarked would make the bot
        # reconsider it every night forever.
        for day in days:
            mark_reported(self.store, group_id, day)

    async def announce_release(self) -> None:
        """Tell every watched group about a version it has not seen yet."""
        await announce_all(
            self.transport,
            self.store,
            list(self.directory.groups),
            load_changelog(),
            POPE,
            self.portraits,
        )

    async def listen(self) -> None:
        """Consume frames forever, handing each to the dispatcher."""
        async for frame in self.transport.receive():
            # Every frame counts, including receipts and typing indicators:
            # the question this answers is "can anything still reach us?",
            # not "did anybody address the bot?".
            self.liveness.note_envelope()
            await self.dispatcher.handle(frame)


def _register_album(registry: CommandRegistry, directory: Path, rate_limit: Decorator) -> None:
    """Wire the album's commands, all of them reading one mutable holder.

    !random takes the same cooldown as every other photo command; !add_photo
    takes no decorator at all, per "NO CAP, NO LIMITS" -- no cooldown, no
    size cap, no daily limit.
    """
    aliases = load_aliases()
    holder = PackHolder(load_pack(directory))
    register_pack_commands(registry, holder, decorate=rate_limit)
    register_random_command(registry, holder, tuple(aliases["random"]), decorate=rate_limit)
    register_add_command(registry, holder, ExiftoolStripper(), tuple(aliases["add_photo"]))


def build_bot(
    config: Config,
    client: httpx.AsyncClient,
    store: Store,
    transport: Transport,
    directory: GroupDirectory,
    liveness: Liveness,
    clock: Clock = now_local,
) -> Bot:
    """Assemble the object graph from its injected dependencies."""
    registry = CommandRegistry()
    fetcher = ImageFetcher(client)
    portraits = PortraitCache(fetcher, config.commons_api_url)
    rate_limit = cooldown(config.cooldown_seconds, COOLDOWN_MESSAGE)
    register_animal_commands(
        registry,
        fetcher,
        decorate=rate_limit,
        endpoints=config.image_api_urls,
    )
    register_pope_command(registry, portraits, decorate=rate_limit)
    register_stats_commands(registry, decorate=rate_limit)
    # Absent unless this installation has an album, and scoped to that
    # album's own groups when it does -- so on every other machine, and in
    # every other group, these commands simply do not exist.
    if config.photo_pack_dir is not None:
        _register_album(registry, config.photo_pack_dir, rate_limit)
    # Last, so !pomoc trails the list it prints; it reads the registry
    # when it runs, so the order is presentation only.
    register_help_command(registry, decorate=rate_limit)
    dispatcher = Dispatcher(
        config=config,
        directory=directory,
        registry=registry,
        store=store,
        transport=transport,
        clock=clock,
    )
    return Bot(
        config=config,
        store=store,
        transport=transport,
        directory=directory,
        dispatcher=dispatcher,
        liveness=liveness,
        portraits=portraits,
        clock=clock,
    )