#!/bin/bash
set -euo pipefail

show_help() {
    echo "Usage: $0 <output_name> <duration_seconds>"
    echo
    echo "Records audio from the default microphone, applies:"
    echo "  - high-pass filter (remove low-frequency rumble)"
    echo "  - mono conversion"
    echo "  - peak normalization"
    echo "  - trims first 50ms (remove mic crack)"
    echo "  - loudness normalization (LUFS)"
    echo "Outputs WAV to <output_name>.wav and plays it back."
}

stop_recording() {
    echo
    echo "Stopping recording..."
    # 2. Process the recorded audio with sox
    sox "$tmp0" "$tmp1" highpass 120 remix 1,2 gain -n

    # 2. Remove mic crack (first 50ms)
    ffmpeg -hide_banner -loglevel error -i "$tmp1" -ss 0.05 -c copy "$tmp2"

    # 3. Loudness normalize (LUFS) and back to 44100 Hz
    ffmpeg -hide_banner -loglevel error -i "$tmp2" \
    -af "loudnorm=I=-18:TP=-1.5:LRA=7, aresample=44100, pan=mono|c0=0.5*c0+0.5*c1" \
    "${name}.wav"

    # Cleanup temporary files
    rm -f "$tmp0" "$tmp1" "$tmp2"

    # 4. Playback
    echo "Done. Playing back..."
    aplay "${name}.wav"

    echo "Recording saved as ${name}.wav"
}
trap stop_recording SIGINT

if [[ $# -eq 0 || "$1" == "--help" || "$1" == "-h" ]]; then
    show_help
    exit 0
fi

if [[ $# -lt 2 ]]; then
    echo "Error: Missing arguments."
    show_help
    exit 1
fi

name="$1"
duration="$2"

# Temporary files
tmp0="${name}_raw.wav"
tmp1="${name}_ra1w.wav"
tmp2="${name}_trim.wav"

echo "Recording $duration seconds into $name.wav..."

# 1. Record → high-pass → mono → peak normalize
arecord --duration="$duration" --format=cd "$tmp0"

# Remove trap
trap - SIGINT

stop_recording