import numpy as np


def truncate_audio_to_last_n_seconds(audio_array, n_seconds=8, sample_rate=16000):
    """Truncate audio to last n seconds or pad with zeros to meet n seconds."""
    max_samples = n_seconds * sample_rate
    if len(audio_array) > max_samples:
        return audio_array[-max_samples:]
    elif len(audio_array) < max_samples:
        # Pad with zeros at the beginning
        padding = max_samples - len(audio_array)
        return np.pad(audio_array, (padding, 0), mode='constant', constant_values=0)
    return audio_array