#!/usr/bin/env bash
# Run att_wm inside a nested river, as a window in your existing session.
#
# Nothing is installed and no system rebuild is needed — river's wayland
# backend opens a normal window, and att_wm manages what is inside it.
#
#   ./run-nested.sh              # just att_wm
#   ./run-nested.sh --bar        # also start the bundled quickshell bar
#   ./run-nested.sh --term       # also open a terminal to look at
#
# Anything else you pass is run inside the session, e.g.
#   ./run-nested.sh --bar --term
set -euo pipefail

cd "$(dirname "$0")"

if [[ -z ${WAYLAND_DISPLAY:-} ]]; then
	echo "error: no WAYLAND_DISPLAY — this needs an existing Wayland session." >&2
	echo "       On a TTY, use the headless backend instead:" >&2
	echo "         WLR_BACKENDS=headless WLR_HEADLESS_OUTPUTS=1 ./run-nested.sh" >&2
	exit 1
fi

want_bar=0
want_term=0
for arg in "$@"; do
	case $arg in
	--bar) want_bar=1 ;;
	--term) want_term=1 ;;
	*)
		echo "unknown option: $arg" >&2
		exit 1
		;;
	esac
done

bin=zig-out/bin
if [[ ! -x ${bin}/att_wm ]]; then
	echo "==> building"
	./dev.sh bash -c 'zig build'
fi
bin=$(realpath "${bin}")

init=$(mktemp)
trap 'rm -f "${init}"' EXIT
{
	echo '#!/bin/sh'
	# river exports the nested display to its children; surface it so you can
	# point att_wmctl at this instance from another terminal.
	echo 'echo "" >&2'
	echo 'echo "  nested session is on WAYLAND_DISPLAY=$WAYLAND_DISPLAY" >&2'
	echo 'echo "  drive it with:  WAYLAND_DISPLAY=$WAYLAND_DISPLAY '"${bin}"'/att_wmctl state" >&2'
	echo 'echo "" >&2'
	[[ ${want_bar} -eq 1 ]] && echo "quickshell -p $(realpath quickshell) &"
	[[ ${want_term} -eq 1 ]] && echo 'foot &'
	echo "exec ${bin}/att_wm"
} >"${init}"
chmod +x "${init}"

echo "==> starting nested river (close the window to exit)"
exec env WLR_BACKENDS=wayland river -no-xwayland -c "${init}"