from __future__ import annotations

from collections.abc import Callable, Iterable, Sequence
from typing import Protocol

from .models import (
    AudioFrame,
    AudioSegment,
    Message,
    PlaybackResult,
    ReplyDelta,
    Transcript,
    TransportHealth,
    VadResult,
    WakeEvent,
)


class AudioTransport(Protocol):
    def start_input(
        self, device_id: str | None = None, sample_rate: int = 16000, channels: int = 1
    ) -> None:
        ...

    def read_frames(self, timeout_ms: int) -> list[AudioFrame]:
        ...

    def play_pcm(self, segment: AudioSegment, interrupt: bool = False) -> PlaybackResult:
        ...

    def play_pcm_chunks(
        self,
        segment: AudioSegment,
        *,
        chunk_ms: int,
        after_chunk: Callable[[AudioSegment, int], bool] | None = None,
        should_stop: Callable[[], bool] | None = None,
    ) -> PlaybackResult:
        ...

    def flush_input(self) -> int:
        ...

    def stop(self) -> None:
        ...

    def health(self) -> TransportHealth:
        ...


class WakeWordProvider(Protocol):
    def load(self) -> None:
        ...

    def detect(self, frame: AudioFrame) -> WakeEvent | None:
        ...

    def reset(self) -> None:
        ...


class AudioPreprocessor(Protocol):
    def load(self) -> None:
        ...

    def reset(self) -> None:
        ...

    def process_frame(self, frame: AudioFrame) -> AudioFrame:
        ...

    def flush(self) -> list[AudioFrame]:
        ...


class VadProvider(Protocol):
    def load(self) -> None:
        ...

    def analyze(self, frame: AudioFrame) -> VadResult:
        ...

    def reset(self) -> None:
        ...


class SttProvider(Protocol):
    def load(self) -> None:
        ...

    def transcribe(self, segment: AudioSegment) -> Transcript:
        ...


class RealtimeTranscriptSession(Protocol):
    def accept_frame(self, frame: AudioFrame) -> Transcript | None:
        ...

    def finish(self) -> Transcript | None:
        ...


class RealtimeSttProvider(SttProvider, Protocol):
    def start_stream(self) -> RealtimeTranscriptSession:
        ...


class LlmProvider(Protocol):
    def stream_reply(self, messages: Sequence[Message]) -> Iterable[ReplyDelta]:
        ...


class TtsProvider(Protocol):
    def load(self) -> None:
        ...

    def synthesize(self, text: str) -> AudioSegment:
        ...