#!/usr/bin/env bash
# detect-viewer-backends.sh — Detect which VM viewer backends are available.
#
# Outputs a line for each detected backend: "vnc" or "spice"
# Used by DisplayAdapter.detect() to choose the right viewer at runtime.
#
# Exit code 0 always (even if nothing is found — caller handles empty output).

set -euo pipefail

# VNC viewers
if command -v virt-viewer &>/dev/null; then
    echo "spice"
    echo "vnc"
elif command -v remote-viewer &>/dev/null; then
    echo "spice"
    echo "vnc"
elif command -v xvncviewer &>/dev/null || command -v xtightvncviewer &>/dev/null || \
     command -v vinagre &>/dev/null || command -v vncviewer &>/dev/null; then
    echo "vnc"
fi

# SPICE standalone
if command -v spicy &>/dev/null; then
    echo "spice"
fi

exit 0