soundcard-autoconfigure

#!/bin/bash
# /usr/libexec/autoconfigure-soundcard
# This script automatically configures the default soundcard based on the detected devices.
# It runs after ovos-i2csound and when a USB soundcard is connected or removed.

# Main Logic
# 1. If an /etc/OpenVoiceOS/i2c_platform exists, check the detected platform.
# 2. If a soundcard matching the platform is detected, set it as the ALSA default card.
# 3. If no matching soundcard is detected:
#    - Check for USB soundcards and set the first one detected as the ALSA default card.
#    - If no USB soundcard is found, fallback to onboard BCM soundcard.
# 4. If no soundcard is detected, log an error message.

# Constants
OVOS_USER="$(getent passwd 1000 | cut -d: -f1)"  # Get the username of the first non-system user

# Function to detect the active sound server (PipeWire, PulseAudio, or ALSA)
# Returns the sound server type as a string
detect_sound_server() {
    # Check if PipeWire is installed
    if command -v pipewire > /dev/null; then
        echo "pipewire"
    # Check if PulseAudio is installed
    elif command -v pulseaudio > /dev/null; then
        echo "pulse"
    # Check if ALSA is available
    elif command -v aplay > /dev/null && command -v amixer > /dev/null; then
        echo "alsa"
    else
        echo "No sound server detected"
        exit 1
    fi
}

# Detect the sound server
SOUND_SERVER=$(detect_sound_server)

# Card names for different soundcards
MK1_CARD_NAME="snd_rpi_proto"  # Mark 1 soundcard
HDMI_CARD_NAME="vc4-hdmi"       # HDMI soundcard
HEADPHONES_CARD_NAME="bcm2835"  # Onboard soundcard, not available on RPi 5
GOOGLE_VOICEKIT_V1="snd_rpi_googlevoicehat"  # User manually configures this soundcard
RESPEAKER_2MIC="wm8960-soundcard"  # Respeaker 2mic card

# Environment variables for PipeWire (or PulseAudio)
export PULSE_RUNTIME_PATH="/run/user/1000/pulse/"
export XDG_RUNTIME_DIR="/run/user/1000/"

# Enable strict error handling
set -euo pipefail

# Function to handle errors
# Logs an error message and exits the script
# Arguments:
#   $1: Line number where the error occurred
#   $2: Error code
error_handler() {
    local line_no=$1
    local error_code=$2
    log_message "Error (code: ${error_code}) occurred on line ${line_no}"
    exit ${error_code}
}

# Trap errors and call the error handler
trap 'error_handler ${LINENO} $?' ERR

# Function to log messages to both console and a log file
# Arguments:
#   $1: Message to log
log_message() {
    echo "$1"
    echo "$(date) - $1" >> /tmp/autosoundcard.log
}

# Function to check if the script is running as root
# Returns true if running as root, false otherwise
is_root() {
    [ "$(id -u)" -eq 0 ]
}

# ALSA configuration function
# Configures ALSA to use the specified card number as the default
# Arguments:
#   $1: Card number
alsa_configure() {
    local card_number=$1
    log_message "Configuring ALSA at '/home/$OVOS_USER/.asoundrc' with card $card_number"
    echo -e "pcm.!default {\n  type hw\n  card $card_number\n}\nctl.!default {\n  type hw\n  card $card_number\n}" > "/home/$OVOS_USER/.asoundrc"
}

# PipeWire configuration function
# Configures PipeWire to use the specified card as the default sink
# Arguments:
#   $1: Card number
pw_configure() {
    local card_number=$1
    log_message "Configuring ALSA for PipeWire at '/home/$OVOS_USER/.asoundrc'"
    echo -e "pcm.!default $SOUND_SERVER\nctl.!default $SOUND_SERVER" > "/home/$OVOS_USER/.asoundrc"
    log_message "Match card $card_number to audio sink"
    local sink=$(pw_card2sink "$card_number")
    log_message "Setting default sink: $sink"
    wpctl set-default $sink
}

# PulseAudio configuration function
# Configures PulseAudio to use the specified card as the default sink
# Arguments:
#   $1: Card number
pulse_configure() {
    local card_number=$1
    log_message "Configuring ALSA for Pulseaudio at '/home/$OVOS_USER/.asoundrc'"
    echo -e "pcm.!default $SOUND_SERVER\nctl.!default $SOUND_SERVER" > "/home/$OVOS_USER/.asoundrc"

    local sink_name
    sink_name=$(pulse_card2sink "$card_number")
    # If sink name is found, set it as the default using pactl
    if [ "$sink_name" != "Card index not found" ]; then
        log_message "Setting default sink to: $sink_name"
        # Use pactl to set the default sink for PulseAudio
        if is_root; then
            runuser -u "$OVOS_USER" -- pactl set-default-sink "$sink_name"
        else
            pactl set-default-sink "$sink_name"
        fi
        log_message "Default sink set to: $sink_name"
    else
        log_message "Failed to map card number to output sink. Unable to set default sink."
    fi
}

pw_card2sink() {
    local CARD_IDX=$1

    if [ "$SOUND_SERVER" == "alsa" ]; then
        echo "alsa does not support individual sinks"
        exit 1
    elif [ "$SOUND_SERVER" == "pulseaudio" ]; then
        echo "pulseaudio support not implemented"
        exit 1
    elif [ "$SOUND_SERVER" == "pipewire" ]; then
       # Extract sink IDs
        SINK_IDS=$(wpctl status | awk -v card_idx="$CARD_IDX" '
            /├─ Sinks:/ {capture = 1; next}
            /^ ├─|^ └─|^$/ {capture = 0}
            capture {
                if ($2 == "*") {
                    gsub(/\.$/, "", $3)
                    print $3
                }
                if ($2 ~ /^[0-9]+\.$/) {
                    gsub(/\.$/, "", $2)
                    print $2
                }
            }
        ')

        # Loop through each sink ID and inspect it
        for SINK in $SINK_IDS; do
            CIDX=$(wpctl inspect $SINK | grep -i "api.alsa.pcm.card" | awk -F'"' '{print $2}')
            if [ "$CIDX" == "$CARD_IDX" ]; then
              echo "$SINK"
            fi
        done
    else
        echo "Unsupported sound server: $SOUND_SERVER"
        exit 1
    fi
}

# Function to get the sink name associated with a given card index
# Args:
#   $1: The card index to search for
# Returns:
#   The sink name associated with the card index or an error message if not found
pulse_card2sink() {
    local card_index="$1"
    if is_root; then
        runuser -u "$OVOS_USER" -- pactl list sinks | awk -v card_index="$card_index" '
          BEGIN {found = 0}
          /Name: / { name = $2 }
          /api.alsa.card/ {
              gsub(/"/, "", $3)
              if ($3 == card_index) {
                  print name
                  found = 1
              }
          }
          END { if (found == 0) { print "Card index not found" } }'
    else
        pactl list sinks | awk -v card_index="$card_index" '
          BEGIN {found = 0}
          /Name: / { name = $2 }
          /api.alsa.card/ {
              gsub(/"/, "", $3)
              if ($3 == card_index) {
                  print name
                  found = 1
              }
          }
          END { if (found == 0) { print "Card index not found" } }'
    fi
}

# Function to set up a sound card based on its detected type
# Arguments:
#   $1: Card index
setup_card() {
    local card_index="$1"
    case "$SOUND_SERVER" in
      *pipewire*) pw_configure $card_index ;;
      *pulse*) pulse_configure $card_index ;;
      *) alsa_configure $card_index ;;
    esac
}

# Wait for ovos-i2csound to complete setup
sleep 1

# Read i2c platform configuration from file
if [ -f /etc/OpenVoiceOS/i2c_platform ]; then
    i2c_platform=$(cat /etc/OpenVoiceOS/i2c_platform)
else
    log_message "/etc/OpenVoiceOS/i2c_platform not found."
    i2c_platform=""
fi

log_message "$(aplay -l)"  # Log detected soundcards

# Function to set up Respeaker 2mic soundcard
setup_wm8960_soundcard() {
    log_message "Respeaker-2mic (wm8960) detected by ovos-i2csound."
    if aplay -l | grep "$RESPEAKER_2MIC"; then
        local CARD_NUMBER=$(aplay -l | grep "$RESPEAKER_2MIC" | awk '{print $2}' | cut -d':' -f1)
        log_message "Detected CARD_NUMBER for Respeaker-2mic soundcard: $CARD_NUMBER"
        setup_card "$CARD_NUMBER"
    else
        log_message "Error: ovos-i2csound detected Respeaker-2mic but 'aplay -l' could not detect '$RESPEAKER_2MIC'"
        exit 1
    fi
}

# Function to set up Mark 1 soundcard
setup_mark1_soundcard() {
    log_message "Mark 1 soundcard detected by ovos-i2csound."
    if aplay -l | grep "$MK1_CARD_NAME"; then
        local CARD_NUMBER=$(aplay -l | grep "$MK1_CARD_NAME" | awk '{print $2}' | cut -d':' -f1)
        log_message "Detected CARD_NUMBER for Mark 1 soundcard: $CARD_NUMBER"
        setup_card "$CARD_NUMBER"
    else
        log_message "Error: ovos-i2csound detected Mark 1 but 'aplay -l' could not detect '$MK1_CARD_NAME'"
        exit 1
    fi
}

# Function to set up GoogleVoiceKit soundcard
setup_googlevoicekitv1_soundcard() {
    # NOTE: special case, not detected by ovos-i2csound (yet)
    #  just a placeholder, ovos-i2csound will need to grep boot/config.txt to check if overlay is enabled
    log_message "GoogleVoiceKit soundcard configured by user"
    if aplay -l | grep "$GOOGLE_VOICEKIT_V1"; then
        local CARD_NUMBER=$(aplay -l | grep "$GOOGLE_VOICEKIT_V1" | awk '{print $2}' | cut -d':' -f1)
        log_message "Detected CARD_NUMBER for GoogleVoiceKit soundcard: $CARD_NUMBER"
        setup_card "$CARD_NUMBER"
    else
        log_message "Error: user configured GoogleVoiceKit but 'aplay -l' could not detect '$GOOGLE_VOICEKIT_V1'"
        exit 1
    fi
}

# Function to set up fallback soundcard
setup_fallback_soundcard() {
    local USB_CARD=""
    # Check for USB soundcard
    if aplay -l | grep "card" | grep -i "usb"; then
        local USB_CARDS=$(aplay -l | grep "card" | grep -i "usb" | awk '{print $2}' | cut -d':' -f1)
        # If multiple USB soundcards are detected, log a warning and pick the last one
        if [ -n "$USB_CARDS" ]; then
            local CARD_COUNT=$(echo "$USB_CARDS" | wc -l)
            if [ "$CARD_COUNT" -gt 1 ]; then
                log_message "Warning: Multiple USB soundcards detected. Using the last detected card."
            fi
            # Select the last USB soundcard detected
            USB_CARD=$(echo "$USB_CARDS" | tail -n 1)
        fi
    fi

    if [ -n "$USB_CARD" ]; then
        # Set ALSA defaults for the detected USB soundcard
        log_message "USB soundcard detected."
        setup_card "$USB_CARD"
    else
        # Check for any other non-BCM soundcard (prioritize user-installed cards over onboard ones)
        local OTHER_CARD=$(aplay -l | grep "card"  | grep -v -i "$HEADPHONES_CARD_NAME" | grep -v -i "$HDMI_CARD_NAME" | awk '{print $2}' | cut -d':' -f1 | head -n 1)
        if [ -n "$OTHER_CARD" ]; then
            # Set ALSA defaults for the user-installed soundcard
            log_message "User-installed soundcard detected."
            setup_card "$OTHER_CARD"
        else
            # Default to onboard BCM soundcard if no other card is found
            local BCM_CARD=$(aplay -l | grep "card" | grep -i "$HEADPHONES_CARD_NAME" | awk '{print $2}' | cut -d':' -f1 | head -n 1)
            if [ -n "$BCM_CARD" ]; then
                # Set ALSA defaults for the onboard BCM soundcard
                log_message "Onboard BCM soundcard detected."
                setup_card "$BCM_CARD"
            else
                # Fall back to HDMI soundcard if no onboard card is found
                local HDMI_CARD=$(aplay -l | grep "card" | grep -i "$HDMI_CARD_NAME" | awk '{print $2}' | cut -d':' -f1 | head -n 1)
                if [ -n "$HDMI_CARD" ]; then
                    # Set ALSA defaults for the HDMI soundcard
                    log_message "HDMI soundcard detected."
                    setup_card "$HDMI_CARD"
                else
                    # No suitable soundcard detected, log an error
                    log_message "Error: No suitable soundcard detected."
                fi
            fi
        fi
    fi
}

# Autoconfigure default soundcard
# TODO - possible values not handled (some might be mic input only)
#   "SJ201V6" "SJ201V10" "AIYVOICEBONNET", "ADAFRUIT", "RESPEAKER6", "RESPEAKER4"
case "$i2c_platform" in
    *WM8960*)
        # inform user about possible MK1 arduino boot failure
        # we have no way to know, it will just report as WM8960
        log_message "WARNING [Mark1 only]: If this is a Mark 1 device, Arduino may not have booted properly. Power cycle your device until the eyes spin."
        setup_wm8960_soundcard
        ;;
    *MARK1*)
        setup_mark1_soundcard
        ;;
    *)
        setup_fallback_soundcard
        ;;
esac