#!/bin/bash
# Capture a short stereo sample from the barepi mic path and print per-channel stats.
# Usage:
#   ./test-mics.sh [seconds] [out.wav]
#   ./test-mics.sh --thsel-high [seconds] [out.wav]
#   ./test-mics.sh --thsel-low  [seconds] [out.wav]

set -euo pipefail

RATE=48000
FORMAT=S32_LE
CHANNELS=2
DURATION=3
OUT=""
THSEL=""
CAPTURE_PCM="${CAPTURE_PCM:-barepi_capture}"

usage() {
  cat <<'EOF'
Usage:
  ./test-mics.sh [seconds] [out.wav]
  ./test-mics.sh --thsel-high [seconds] [out.wav]
  ./test-mics.sh --thsel-low  [seconds] [out.wav]
EOF
}

set_thsel() {
  local level="$1"
  command -v pinctrl >/dev/null 2>&1 || return 0
  if [ "$level" = "high" ]; then
    sudo pinctrl set 8 op pn dh >/dev/null
  else
    sudo pinctrl set 8 op pn dl >/dev/null
  fi
}

prepare_wake_pin() {
  command -v pinctrl >/dev/null 2>&1 || return 0
  sudo pinctrl set 13 ip pn >/dev/null 2>&1 || true
}

show_pins() {
  command -v pinctrl >/dev/null 2>&1 || return 0
  sudo pinctrl get 8,13 || true
}

positional=()
while [ $# -gt 0 ]; do
  case "$1" in
    --thsel-high)
      THSEL="high"
      shift
      ;;
    --thsel-low)
      THSEL="low"
      shift
      ;;
    -h|--help)
      usage
      exit 0
      ;;
    *)
      positional+=("$1")
      shift
      ;;
  esac
done

if [ ${#positional[@]} -ge 1 ]; then
  DURATION="${positional[0]}"
fi
if [ ${#positional[@]} -ge 2 ]; then
  OUT="${positional[1]}"
fi
if [ -z "$OUT" ]; then
  OUT="/tmp/barepi-mics-$(date +%Y%m%d-%H%M%S).wav"
fi

if ! arecord -L 2>/dev/null | grep -qx 'barepi_capture'; then
  CAPTURE_PCM="plughw:CARD=barepiaudio,DEV=0"
fi

if [ -n "$THSEL" ]; then
  set_thsel "$THSEL"
fi
prepare_wake_pin
show_pins

echo "Recording ${DURATION}s from ${CAPTURE_PCM} -> ${OUT}"
arecord -q -D "$CAPTURE_PCM" -f "$FORMAT" -c "$CHANNELS" -r "$RATE" -d "$DURATION" "$OUT"

python3 - <<'PY' "$OUT"
import math
import struct
import sys
import wave

path = sys.argv[1]
with wave.open(path, 'rb') as w:
    channels = w.getnchannels()
    width = w.getsampwidth()
    rate = w.getframerate()
    frames = w.getnframes()
    data = w.readframes(frames)

if channels != 2 or width != 4:
    print(f"Recorded {channels}ch / {width * 8}bit at {rate} Hz")
    sys.exit(0)

samples = list(struct.iter_unpack('<ii', data))
left = [l for l, _ in samples]
right = [r for _, r in samples]

def rms(xs):
    return math.sqrt(sum(x * x for x in xs) / len(xs)) if xs else 0.0

def peak(xs):
    return max((abs(x) for x in xs), default=0)

l_rms = rms(left)
r_rms = rms(right)
l_peak = peak(left)
r_peak = peak(right)
full_scale = float(2**31 - 1)

print(f"Saved: {path}")
print(f"Rate: {rate} Hz  Frames: {frames}")
print(f"Left : rms={int(l_rms):>10} peak={l_peak:>10} peak_dBFS={20*math.log10(max(l_peak,1)/full_scale):6.1f}")
print(f"Right: rms={int(r_rms):>10} peak={r_peak:>10} peak_dBFS={20*math.log10(max(r_peak,1)/full_scale):6.1f}")
PY