uno-q-audio-synth/scripts/start-synth.sh

#!/bin/bash
set -euo pipefail

PD_DIR="/home/arduino/pd"
PATCH="$PD_DIR/synth.pd"
MODE="usb"
VERBOSE=false

die() { echo "[ERROR] $*" >&2; exit 1; }
info() { echo "[INFO] $*"; }

while [ $# -gt 0 ]; do
    case "$1" in
        -a|--auto)     MODE="auto"; shift ;;
        -i|--i2s)      MODE="i2s"; shift ;;
        -l|--loopback) MODE="loopback"; shift ;;
        -v|--verbose)  VERBOSE=true; shift ;;
        -k|--kill)     pkill -x pd 2>/dev/null && info "Pd stopped" || info "Pd not running"; exit 0 ;;
        *) die "Unknown option: $1" ;;
    esac
done

if ! command -v pd &>/dev/null; then
    die "Pure Data not found. Install: apt install puredata"
fi

if [ ! -f "$PATCH" ]; then
    die "Patch not found: $PATCH"
fi

# --- Auto-detect mode ---
if [ "$MODE" = "auto" ]; then
    if [ -f /run/usb-role ]; then
        ROLE=$(cat /run/usb-role)
    else
        ROLE=$(/usr/local/bin/detect-usb-role.sh 2>/dev/null && cat /run/usb-role || echo "gadget")
    fi

    case "$ROLE" in
        gadget)
            MODE="usb"
            if ! aplay -l 2>/dev/null | grep -q "UAC1Gadget"; then
                info "Configuring USB gadget..."
                /usr/local/bin/configure-usb-audio.sh start 2>/dev/null || true
                sleep 1
            fi
            ;;
        host)
            if [ -f /run/usb-audio-dev ] && [ -s /run/usb-audio-dev ]; then
                ALSA_DEV=$(cat /run/usb-audio-dev)
            else
                info "Detecting USB audio interface..."
                /usr/local/bin/configure-usb-host.sh 2>/dev/null || {
                    die "No USB audio interface found. Plug one in via hub."
                }
                ALSA_DEV=$(cat /run/usb-audio-dev)
            fi
            info "Mode: USB host (MIDI controller + USB audio interface)"
            # MIDI handled by midi-bridge.service → UDP → Pd netreceive
            AUDIO_OPTS=(-audiooutdev 4 -audioindev 4)
            PD_ARGS=(
                -nogui -alsa
                -send "pd dsp 1"
                "${AUDIO_OPTS[@]}"
                -audiobuf 20 -blocksize 64 -r 48000
                -channels 2 -inchannels 0 -outchannels 2
                -path "$PD_DIR" "$PATCH"
            )
            if [ "$VERBOSE" = true ]; then pd "${PD_ARGS[@]}"
            else pd "${PD_ARGS[@]}" > /dev/null 2>&1 &
                 PID=$!; info "Pd started (PID: $PID)"; info "  Stop: kill $PID"
            fi
            exit 0
            ;;
        *)
            info "Auto-detect: unknown role '$ROLE', falling back to gadget"
            MODE="usb"
            ;;
    esac
fi

# --- Configure per-mode options ---
AUDIO_OPTS=()

if [ "$MODE" = "usb" ]; then
    info "Mode: USB gadget (UAC1 audio + gmidi MIDI)"
    AUDIO_OPTS=(-audiooutdev 2 -audioindev 2)
    if aplay -l 2>/dev/null | grep -q "UAC1Gadget"; then
        info "  USB gadget: OK"
        # MIDI handled by midi-bridge.service → UDP → Pd netreceive
    else
        info "  USB gadget: NOT DETECTED (kernel modules needed)"
    fi
fi

if [ "$MODE" = "i2s" ]; then
    if [ -f /run/i2s-audio-dev ] && [ -s /run/i2s-audio-dev ]; then
        ALSA_DEV=$(cat /run/i2s-audio-dev)
    else
        for dev in "hw:I2S,0" "hw:MI2S,0" "hw:0,0"; do
            if aplay -l 2>/dev/null | grep -qi "${dev%,*}"; then
                ALSA_DEV="$dev"
                break
            fi
        done
    fi
    info "Mode: I2S DAC (standalone analog audio)"
    AUDIO_OPTS=(-audioadddev "$ALSA_DEV")
fi

if [ "$MODE" = "loopback" ]; then
    info "Mode: ALSA loopback (testing)"
    AUDIO_OPTS=(-audiodev 2)
fi

PD_ARGS=(
    -nogui -alsa
    -send "pd dsp 1"
    "${AUDIO_OPTS[@]}"
    -audiobuf 20 -blocksize 64 -r 48000
    -channels 1 -inchannels 0 -outchannels 1
    -path "$PD_DIR" "$PATCH"
)

if [ "$VERBOSE" = true ]; then
    pd "${PD_ARGS[@]}" &
else
    pd "${PD_ARGS[@]}" > /dev/null 2>&1 &
fi
PID=$!
info "Pd started (PID: $PID)"
info "  Stop: kill $PID"
wait $PID
info "Pd exited (code: $?)"