#!/usr/bin/env bash
# reference WAV를 mono 24kHz로 정규화
set -euo pipefail

if [[ $# -lt 1 ]]; then
  echo "Usage: $0 input.wav [output.wav]"
  exit 1
fi

IN="$1"
OUT="${2:-${IN%.wav}_24k_mono.wav}"

ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
PY="${ROOT}/.venvs/api/bin/python"
if [[ ! -x "$PY" ]]; then
  PY=python3
fi

"$PY" - <<PY
import sys
try:
    import soundfile as sf
    import numpy as np
except ImportError:
    print("soundfile 필요: pip install soundfile")
    sys.exit(1)

data, sr = sf.read("$IN", always_2d=False)
if data.ndim > 1:
    data = data.mean(axis=1)
target_sr = 24000
if sr != target_sr:
    import librosa
    data = librosa.resample(data.astype(float), orig_sr=sr, target_sr=target_sr)
    sr = target_sr
sf.write("$OUT", data, sr, subtype="PCM_16")
print(f"Saved: $OUT ({sr} Hz mono)")
PY