#!/bin/bash
# Start the WebXR Chromium build. frame/install.sh copies this to
# ~/.local/bin/chromium-xr; the Steam library shortcut and the desktop entry
# both run it. Arguments go to Chromium, so `chromium-xr URL` opens a page.
set -euo pipefail

CHROME="${CHROMIUM_XR_HOME:-$HOME/chromium-xr}/chrome"
[[ -x "$CHROME" ]] || { echo "chromium-xr: no build at $CHROME (run frame/install.sh)" >&2; exit 1; }

# Steam preloads its in-game overlay (gameoverlayrenderer.so) into anything it
# launches. It segfaults in Chromium's zygote, the GPU process then can't
# start, and Chromium quits with "GPU process isn't usable". Drop it and keep
# anything else that was preloaded.
if [[ -n "${LD_PRELOAD:-}" ]]; then
  keep=()
  # Split on spaces and colons only, like ld.so, with no glob expansion.
  # read -d '' takes the whole value, newlines included (it returns 1 at EOF).
  IFS=' :' read -r -d '' -a libs < <(printf '%s' "$LD_PRELOAD") || true
  for lib in ${libs[@]+"${libs[@]}"}; do
    [[ -z "$lib" || "$lib" == *gameoverlayrenderer.so ]] || keep+=("$lib")
  done
  if (( ${#keep[@]} )); then
    LD_PRELOAD=${keep[0]}
    for lib in "${keep[@]:1}"; do LD_PRELOAD+=":$lib"; done
    export LD_PRELOAD
  else
    unset LD_PRELOAD
  fi
fi

# --enable-features=OpenXR: the Linux OpenXR device is off by default.
# --ozone-platform=x11: gamescope's X display, where each app is a panel.
# --no-first-run and --password-store=basic: otherwise startup can stop at a
#   first-run or keyring prompt you can't see.
# --disable-seccomp-filter-sandbox: with the XR process's seccomp policy on,
#   SteamVR sees the wrong process ID and refuses the session (see
#   docs/technical-notes.md). The namespace sandbox stays on.
exec "$CHROME" \
  --user-data-dir="$HOME/.config/chromium-xr" \
  --enable-features=OpenXR \
  --ozone-platform=x11 \
  --no-first-run --no-default-browser-check --password-store=basic \
  --disable-seccomp-filter-sandbox \
  "$@"
