#!/sbin/openrc-run
# Copyright 1999-2026 Gentoo Authors
# Distributed under the terms of the GNU General Public License v2

description="Lemonade local AI server (lemond) — OpenAI-compatible LLM inference."

# Design note: the systemd unit runs lemond as the dedicated acct-user
# 'lemonade'. OpenRC intentionally does NOT assume that account -- it runs
# as an admin-chosen LEMONADE_USER that already owns ~/.cache/lemonade.
# This asymmetry is deliberate; don't "unify" the two onto the lemonade
# system user without rechecking cache ownership.

# Set LEMONADE_USER in /etc/conf.d/lemonade. No default — the service
# refuses to start until it's configured.
: ${LEMONADE_USER:=}
: ${LEMONADE_HOST:=127.0.0.1}
: ${LEMONADE_PORT:=}
: ${LEMONADE_CACHE:=}
: ${LEMONADE_LOG:=/var/log/lemonade.log}
: ${LEMONADE_EXTRA_OPTS:=}
# Writable runtime dir exported as XDG_RUNTIME_DIR; lemond refuses to start
# without one. Mirrors the upstream systemd unit's RuntimeDirectory=lemonade.
# See conf.d for the full rationale. Empty disables the creation/export.
: ${LEMONADE_RUNTIME_DIR:=/run/lemonade}
# Reuse the system ROCm runtime for lemond's bundled ROCm backends instead of
# fetching AMD's multi-GB TheRock runtime; /usr is Gentoo's ROCm prefix. See
# conf.d for the full rationale. Empty disables the export.
: ${LEMONADE_ROCM_PATH:=/usr}

supervisor="supervise-daemon"
command="/usr/bin/lemond"
output_log="${LEMONADE_LOG}"
error_log="${LEMONADE_LOG}"
respawn_delay=5
# never give up restarting; the inference daemon is long-lived
respawn_max=0

# Mirror the upstream systemd unit's CAP_SYS_RESOURCE grant: give the
# dropped user rlimit headroom for mmap/mlock of large model weights.
rc_ulimit="-l unlimited"

depend() {
	need net
	after net
}

start_pre() {
	if [ -z "${LEMONADE_USER}" ]; then
		eerror "LEMONADE_USER is not set in /etc/conf.d/lemonade."
		eerror "Set it to the local user that owns the lemonade cache."
		return 1
	fi
	if ! getent passwd "${LEMONADE_USER}" > /dev/null; then
		eerror "User '${LEMONADE_USER}' not found on this system."
		return 1
	fi
	if [ -z "${LEMONADE_CACHE}" ]; then
		local home
		home="$(getent passwd "${LEMONADE_USER}" | cut -d: -f6)"
		LEMONADE_CACHE="${home}/.cache/lemonade"
	fi
	# supervise-daemon opens the stdout/stderr redirect (LEMONADE_LOG) itself,
	# as the dropped user (not as root), and dup2s it onto the child's fds.
	# /var/log is root-owned, so that open fails and lemond never gets a valid
	# stdout -- it dies before writing a line. Pre-create the log user-owned so
	# the redirect opens; 0640 keeps it off other local users.
	if [ -n "${LEMONADE_LOG}" ]; then
		checkpath -f -m 0640 -o "${LEMONADE_USER}:${LEMONADE_USER}" \
			"${LEMONADE_LOG}" || return 1
	fi
	# lemond needs a writable XDG_RUNTIME_DIR for its control socket and
	# runtime state, and refuses to start without one. supervise-daemon's
	# clean environment has none -- elogind's /run/user/<uid> only exists
	# after an interactive login, which a boot-time service can't rely on.
	# Create a dedicated dir owned by the dropped user (mirroring the upstream
	# systemd unit's RuntimeDirectory=lemonade) and export it.
	if [ -n "${LEMONADE_RUNTIME_DIR}" ]; then
		checkpath -d -m 0700 -o "${LEMONADE_USER}:${LEMONADE_USER}" \
			"${LEMONADE_RUNTIME_DIR}" || return 1
		export XDG_RUNTIME_DIR="${LEMONADE_RUNTIME_DIR}"
	fi
	# Reuse the system ROCm runtime (skips the multi-GB TheRock download) for
	# lemond's bundled ROCm backends. No-op unless a ROCm backend is selected
	# and a ROCm runtime is actually present at this path.
	[ -n "${LEMONADE_ROCM_PATH}" ] && export ROCM_PATH="${LEMONADE_ROCM_PATH}"
	# --host overrides config.json, so 127.0.0.1 here forces a loopback
	# bind regardless of what config.json carries. Set LEMONADE_HOST to
	# 0.0.0.0 in /etc/conf.d/lemonade ONLY behind API-key auth
	# (LEMONADE_API_KEY) or a trusted transport (SSH tunnel / WireGuard);
	# lemond has no built-in TLS.
	local args="--host ${LEMONADE_HOST}"
	[ -n "${LEMONADE_PORT}" ] && args="${args} --port ${LEMONADE_PORT}"
	[ -n "${LEMONADE_EXTRA_OPTS}" ] && args="${args} ${LEMONADE_EXTRA_OPTS}"
	args="${args} ${LEMONADE_CACHE}"
	command_args="${args}"
	command_user="${LEMONADE_USER}:${LEMONADE_USER}"
}