vcable.sh

#!/usr/bin/env bash
# =========================================================================
# vcable: Transparent Virtual Audio Cable Installer
# Architecture: Minimalist + Systemd Persistence + Auto Dependency
# Features: Daemon-Crash Resilient (Auto-restarts on PipeWire restart)
# =========================================================================
set -e

GREEN='\033[0;32m'
BLUE='\033[0;34m'
YELLOW='\033[1;33m'
RED='\033[0;31m'
NC='\033[0m'

echo -e "${BLUE}[*] Starting vcable Installation...${NC}\n"

# Safety Warning
echo -e "${RED}======================================================================${NC}"
echo -e "${YELLOW}IMPORTANT PRE-INSTALLATION STEP:${NC}"
echo -e "Please close all applications currently using your microphone or"
echo -e "speakers (e.g., OBS Studio, Discord, Zoom, Spotify, Web Browsers)."
echo -e "The installation will restart your audio engine, which may cause"
echo -e "active audio applications to crash or lose sound if left open."
echo -e "${RED}======================================================================${NC}\n"

read -p "Press [ENTER] when all audio apps are closed, or [Ctrl+C] to abort..."

# Dependency Check & Auto-Install
echo -e "${YELLOW}>> Executing: command -v pactl${NC}"
if ! command -v pactl &> /dev/null; then
    echo -e "${YELLOW}[!] 'pactl' is missing. The 'pulseaudio-utils' package is required.${NC}"
    read -p "   Do you want to install it now? (Requires sudo password) [Y/n]: " choice
    case "$choice" in 
      y|Y|yes|Yes|"")
        echo -e "${BLUE}[*] Detecting package manager...${NC}"
        if command -v apt &> /dev/null; then
            sudo apt update && sudo apt install -y pulseaudio-utils
        elif command -v dnf &> /dev/null; then
            sudo dnf install -y pulseaudio-utils
        elif command -v pacman &> /dev/null; then
            sudo pacman -S --noconfirm libpulse
        else
            echo -e "${RED}[!] Unsupported OS. Please install 'pulseaudio-utils' manually.${NC}"
            exit 1
        fi
        echo -e "${GREEN}[✓] Dependency installed successfully!${NC}\n"
        ;;
      *)
        echo -e "${RED}[!] Installation aborted. Cannot proceed without dependencies.${NC}"
        exit 1
        ;;
    esac
else
    echo -e "${GREEN}[✓] 'pactl' is already installed.${NC}\n"
fi

# Server Detection
echo -e "${YELLOW}>> Executing: pactl info | grep 'Server Name'${NC}"
SERVER=$(pactl info | grep "Server Name")
if [[ "$SERVER" == *"PipeWire"* ]]; then 
    SYS="pipewire"
    echo -e "${GREEN}[✓] Detected: PipeWire${NC}\n"
elif [[ "$SERVER" == *"PulseAudio"* ]]; then 
    SYS="pulseaudio"
    echo -e "${GREEN}[✓] Detected: PulseAudio${NC}\n"
else 
    echo -e "${RED}[!] Error: Unknown audio server.${NC}"; exit 1
fi

# Directory Setup
SCRIPT_DIR="$HOME/.local/bin"
SYSTEMD_DIR="$HOME/.config/systemd/user"
ROUTING_SCRIPT="$SCRIPT_DIR/vcable-bridge.sh"
SERVICE_FILE="$SYSTEMD_DIR/vcable.service"

echo -e "${YELLOW}>> Executing: mkdir -p $SCRIPT_DIR $SYSTEMD_DIR${NC}"
mkdir -p "$SCRIPT_DIR" "$SYSTEMD_DIR"
echo ""

# Generate Core Script
echo -e "${YELLOW}>> Generating $ROUTING_SCRIPT...${NC}"
if [ "$SYS" == "pipewire" ]; then
cat << 'EOF' > "$ROUTING_SCRIPT"
#!/usr/bin/env bash
pactl load-module module-null-sink media.class=Audio/Sink sink_name="VirtualSpeaker" sink_properties="device.description='Virtual-Speaker'"
pactl load-module module-null-sink media.class=Audio/Source/Virtual sink_name="VirtualMic" sink_properties="device.description='Virtual-Mic'" channel_map=front-left,front-right
sleep 2
pw-link VirtualSpeaker:monitor_FL VirtualMic:input_FL
pw-link VirtualSpeaker:monitor_FR VirtualMic:input_FR
EOF
elif [ "$SYS" == "pulseaudio" ]; then
cat << 'EOF' > "$ROUTING_SCRIPT"
#!/usr/bin/env bash
pactl load-module module-null-sink sink_name="VirtualSpeaker" sink_properties="device.description='Virtual-Speaker'"
pactl load-module module-remap-source source_name="VirtualMic" master="VirtualSpeaker.monitor" source_properties="device.description='Virtual-Mic'"
EOF
fi

echo -e "${YELLOW}>> Executing: chmod +x $ROUTING_SCRIPT${NC}"
chmod +x "$ROUTING_SCRIPT"
echo ""

# Generate Systemd Service (WITH SYMBIOTIC BINDING)
echo -e "${YELLOW}>> Generating $SERVICE_FILE...${NC}"

if [ "$SYS" == "pipewire" ]; then
    BIND_TARGET="pipewire.service wireplumber.service"
else
    BIND_TARGET="pulseaudio.service"
fi

cat << EOF > "$SERVICE_FILE"
[Unit]
Description=Virtual Audio Bridge ($SYS)
Requires=$BIND_TARGET
After=$BIND_TARGET
PartOf=$BIND_TARGET

[Service]
Type=oneshot
ExecStart=$ROUTING_SCRIPT
RemainAfterExit=yes

[Install]
WantedBy=default.target
EOF
echo ""

# Apply & Restart Services
echo -e "${YELLOW}>> Executing: systemctl --user daemon-reload${NC}"
systemctl --user daemon-reload

echo -e "${YELLOW}>> Executing: systemctl --user restart pipewire pipewire-pulse wireplumber${NC}"
systemctl --user restart pipewire pipewire-pulse wireplumber || true
sleep 1

echo -e "${YELLOW}>> Executing: systemctl --user enable --now vcable.service${NC}"
systemctl --user enable --now vcable.service &> /dev/null

echo -e "\n${GREEN}[✓] Installation Complete!${NC}"
echo -e "Virtual cables are now fully resilient. If the audio daemon crashes or restarts, the cables will auto-rebuild."