"""This module contains utils methods for extraction audio metadata."""

from constants import errors  # noqa
from constants import transcoding_types  # noqa


def get_lossless_flag(codec, mime_type):
    """Get lossless flag for m4a or flac mime types and codecs.

    Args:
       codec (str): Short codec name.
       mime_type (str): MIME type of input file object.
    Returns:
       bool: True if it's lossless.

    """
    file_is_wav_pcm = ((mime_type in transcoding_types.WAV_MIME_TYPES) and (
        codec == transcoding_types.PCM_CODEC_NAME))
    file_is_flac = mime_type in transcoding_types.FLAC_MIME_TYPES
    file_is_m4a_alac = ((mime_type in transcoding_types.MP4_MIME_TYPES) and (
        codec == transcoding_types.ALAC_CODEC_NAME))
    if any([file_is_flac, file_is_m4a_alac, file_is_wav_pcm]):
        return True
    return False


def get_channel_mode(channels):
    """Get channel mode for count of channels.

    Args:
        channels (int): count of channels.
    Returns:
        str: 'mono', 'stereo' or throw ValueError.
    Raises:
        ValueError: Invalid number of channels.

    """
    if channels not in transcoding_types.AVAILABLE_CHANNELS_MODE:
        error_message = errors.CHANNEL_MODE_ERROR.format(channels=channels)
        raise ValueError(error_message)
    return transcoding_types.AVAILABLE_CHANNELS_MODE[channels]