from typing import NamedTuple

import av

from towhee.operator.base import Operator


AudioOutput = NamedTuple(
    "Outputs",
    [("audio_frame", 'ndarray'),
     ('sample_rate', 'int'),
     ('layout', 'str'),
     ("TIMESTAMP", 'int')]
)


class AudioDecoder(Operator):
    """
    """

    def __init__(self) -> None:
        super().__init__()

    def __call__(self, audio_path: str):
        in_container = av.open(audio_path)
        stream = in_container.streams.get(audio=0)[0]
        for frame in in_container.decode(stream):
            timestamp = int(frame.time * 1000)
            sample_rate = frame.sample_rate
            layout = frame.layout.name
            ndarray = frame.to_ndarray()
            yield AudioOutput(ndarray, sample_rate, layout, timestamp)