"""Orchestrator: wires the perception loop and the conversation loop together."""

from __future__ import annotations

import asyncio
import logging

from .interfaces import (
    Brain,
    FrameSource,
    Reply,
    SpeechToText,
    TextChannel,
    TextToSpeech,
    Utterance,
    VisionBackend,
)
from .state import SharedScreenContext

log = logging.getLogger("wsai.pipeline")


class Pipeline:
    """Runs two concurrent loops:

    * perception: FrameSource -> VisionBackend -> SharedScreenContext
    * conversation: (SpeechToText | TextChannel) -> Brain -> (TextToSpeech | TextChannel)

    Any half can be omitted. With no source/vision it runs eyes-free as a pure
    voice loop (STT -> Brain -> TTS); with no stt/tts it runs text-only; with no
    conversation it is a headless "just watch" configuration.
    """

    def __init__(
        self,
        *,
        source: FrameSource | None = None,
        vision: VisionBackend | None = None,
        brain: Brain,
        stt: SpeechToText | None = None,
        tts: TextToSpeech | None = None,
        text_channel: TextChannel | None = None,
        history_turns: int = 12,
    ) -> None:
        self.source = source
        self.vision = vision
        self.brain = brain
        self.stt = stt
        self.tts = tts
        self.text_channel = text_channel
        self.context = SharedScreenContext()
        self._history: list[tuple[str, str]] = []
        self._history_turns = history_turns

    # -- perception -------------------------------------------------------- #
    async def _perceive(self) -> None:
        if self.source is None or self.vision is None:
            return  # eyes-free (voice-only) configuration
        async for frame in self.source.frames():
            try:
                obs = await self.vision.describe(frame)
            except Exception:  # a single bad frame must not kill the loop
                log.exception("vision.describe failed")
                continue
            await self.context.update(obs)
            log.debug("screen: %s", obs.text[:120])

    # -- conversation ------------------------------------------------------ #
    async def _handle(self, utt: Utterance) -> None:
        screen = await self.context.latest()
        reply = await self.brain.respond(utt.text, screen, self._history)
        self._remember(utt.text, reply.text)
        await self._emit(reply)

    def _remember(self, user: str, ai: str) -> None:
        self._history.append((user, ai))
        if len(self._history) > self._history_turns:
            self._history = self._history[-self._history_turns :]

    async def _emit(self, reply: Reply) -> None:
        tasks = []
        if self.tts is not None:
            tasks.append(self.tts.speak(reply))
        if self.text_channel is not None:
            tasks.append(self.text_channel.send(reply))
        if not tasks:
            log.info("AI: %s", reply.text)
        else:
            await asyncio.gather(*tasks)

    async def _listen_voice(self) -> None:
        if self.stt is None:
            return
        async for utt in self.stt.utterances():
            await self._handle(utt)

    async def _listen_text(self) -> None:
        if self.text_channel is None:
            return
        async for utt in self.text_channel.messages():
            await self._handle(utt)

    # -- lifecycle --------------------------------------------------------- #
    async def run(self) -> None:
        # A TaskGroup (not bare gather) so that if ONE loop raises, the others
        # are cancelled and awaited before teardown. With plain gather the
        # failing loop propagated while the siblings kept running detached, and
        # aclose() in the finally then closed a source/stt out from under a
        # still-live loop (close-during-use).
        try:
            async with asyncio.TaskGroup() as tg:
                tg.create_task(self._perceive())
                tg.create_task(self._listen_voice())
                tg.create_task(self._listen_text())
        finally:
            await self.aclose()

    async def aclose(self) -> None:
        for closer in (self.source, self.stt, self.text_channel):
            if closer is not None:
                try:
                    await closer.aclose()
                except Exception:
                    log.exception("error closing %s", closer)