#!/bin/bash
# configure-usb-host.sh — Wait for USB audio interface in host mode.
# Finds the first USB audio capture/playback device and writes device
# info to /run/usb-audio-dev for Pd to use.
#
# When the Uno Q acts as USB host (MIDI controller + USB audio interface
# connected via hub), the USB audio interface appears as a ALSA card
# driven by snd-usb-audio.

set -euo pipefail

DEV_FILE="/run/usb-audio-dev"
POLL_SECONDS=10

die() { echo "[USB-HOST] $*" >&2; exit 1; }
info() { echo "[USB-HOST] $*"; }

info "Waiting for USB audio interface..."

for ((i = 0; i < POLL_SECONDS; i++)); do
    # Look for USB audio cards (not UAC1Gadget, not internal)
    cards=$(aplay -l 2>/dev/null | grep -i "usb" | grep -vi "gadget" || true)
    if [ -n "$cards" ]; then
        # Pick the first USB audio card
        card=$(echo "$cards" | head -1 | awk '{print $2}' | tr -d ':')
        info "Found USB audio card: $card"
        echo "hw:$card,0" > "$DEV_FILE"
        cat "$DEV_FILE"
        exit 0
    fi
    # Also check if any MIDI devices appeared
    if command -v aseqdump &>/dev/null; then
        midi_ports=$(aconnect -i -o -l 2>/dev/null | grep -i "usb" | head -1 || true)
        if [ -n "$midi_ports" ]; then
            info "Found USB MIDI device: $midi_ports"
        fi
    fi
    sleep 1
done

die "No USB audio interface found after ${POLL_SECONDS}s (connect one and restart)"