import sys
import numpy as np
import sounddevice as sd


def record_until_enter(sample_rate=16000):
    """Record audio until user presses Enter. Returns float32 numpy array."""
    print("\n[READY] Press Enter to START recording...")
    input()
    print("[RECORDING] Press Enter to STOP...")

    recording = []

    def callback(indata, frames, time, status):
        if status:
            print(status, file=sys.stderr)
        recording.append(indata.copy())

    with sd.InputStream(samplerate=sample_rate, channels=1, callback=callback):
        input()

    return np.concatenate(recording, axis=0)


def pcm_bytes_to_float32(pcm_bytes):
    """Convert raw 16-bit PCM bytes to float32 array normalized to [-1, 1]."""
    audio_int16 = np.frombuffer(pcm_bytes, dtype=np.int16)
    return audio_int16.astype(np.float32) / 32768.0