[Unit]
Description=Headless Wayland compositor for Sunshine
Documentation=https://docs.lizardbyte.dev/projects/sunshine/
ConditionHost=mainframe

[Service]
Type=simple
# headless for the virtual output, libinput so there is an input backend at
# all. With WLR_BACKENDS=headless alone wlroots creates no libinput backend,
# so the compositor has zero input devices and Sunshine's uinput keyboard and
# mouse are never picked up — the stream shows the desktop and ignores you.
#
# libinput needs a seat, and a systemd --user service sits in no logind
# session, so libseat falls back to seatd. That is why seatd.service is enabled
# on this host and connor is in the seat group.
Environment=WLR_BACKENDS=headless,libinput
Environment=LIBSEAT_BACKEND=seatd
# Do not fail to start when no input device is present yet; Sunshine creates
# its virtual ones only once a client connects.
Environment=WLR_LIBINPUT_NO_DEVICES=1
# Pin the compositor to the NVIDIA card (card0 = 01:00.0, renderD129), which is
# also what sunshine.conf names as its encoder. Without this wlroots picks the
# Intel iGPU and every captured frame crosses GPUs.
Environment=WLR_DRM_DEVICES=/dev/dri/card0
Environment=XDG_CURRENT_DESKTOP=sway
ExecStart=/usr/bin/sway -c %h/.config/sway/headless.conf
ExecStopPost=/usr/bin/systemctl --user stop sunshine.service
Restart=on-failure
RestartSec=5s

# Deliberately NOT WantedBy=default.target. The 3060 also holds the local LLM,
# and this stack costs ~220 MiB of VRAM. Start it with `stream on`; the
# idle-stop timer puts it away again.