"""
服务层接口定义 - TTS 服务
"""
from __future__ import annotations

from abc import ABC, abstractmethod
from typing import Generator, Optional, Tuple
import numpy as np
from loguru import logger


class TTSServiceInterface(ABC):
    """TTS 服务接口 - 所有 TTS 提供者需实现此接口"""
    
    @abstractmethod
    def synthesize(
        self,
        text: str,
        sample_rate: int = 24000,
    ) -> Generator[np.ndarray, None, None]:
        """
        流式合成语音
        
        Args:
            text: 要合成的文本
            sample_rate: 目标采样率
            
        Yields:
            音频块 (numpy array, int16)
        """
        pass
    
    @abstractmethod
    async def initialize(self) -> bool:
        """
        初始化服务（加载模型等）
        
        Returns:
            是否成功
        """
        pass
    
    @abstractmethod
    async def shutdown(self):
        """关闭服务，释放资源"""
        pass


class TTSAudioChunk:
    """TTS 音频块"""
    def __init__(
        self,
        data: bytes,
        turn_id: str = "",
        codec: str = "pcm_s16le",
        sample_rate: int = 24000,
        seq: int = 0,
        is_final: bool = False,
    ):
        self.data = data
        self.turn_id = turn_id
        self.codec = codec
        self.sample_rate = sample_rate
        self.seq = seq
        self.is_final = is_final

    def to_metadata_dict(self) -> dict:
        """转换为协议元数据字典"""
        return {
            "type": "tts_audio_chunk",
            "proto_version": "1.0",
            "transport_profile": "text_uplink",
            "turn_id": self.turn_id,
            "seq": self.seq,
            "codec": self.codec,
            "sample_rate_hz": self.sample_rate,
            "is_final": self.is_final,
        }