# SPDX-License-Identifier: GPL-3.0-only
# SPDX-FileCopyrightText: Copyright (C) 2026 Catcrafts®
[Unit]
Description=Userspace IMS/VoLTE daemon (SIP register + calls over the ims PDN)
# needs the ims PDN (multiplexed netdev + global v6) — ims-pdn-up.sh
# creates/connects the bearer through ModemManager and configures the netdev
After=ModemManager.service network.target
Wants=ModemManager.service

[Service]
Type=simple
# bring up the ims PDN first; waits for modem + LTE attach, idempotent.
# worst case ~4 min (modem wait + connect retries), hence TimeoutStartSec
ExecStartPre=/usr/libexec/ims-pdn-up.sh
TimeoutStartSec=600
# /run/imsd.env: written by ims-pdn-up.sh (DEV= the connected ims netdev).
# /etc/imsd.env: admin configuration — PCSCF= is REQUIRED (the carrier's
# P-CSCF address; see the README's Configuration section) and wins over the
# runtime-derived values.
EnvironmentFile=-/run/imsd.env
EnvironmentFile=-/etc/imsd.env
# registration state (imsreg.state) + media stats live here
StateDirectory=imsd
ExecStart=/usr/bin/imsd
# registration: resume an existing SA when possible (avoids fresh-SA
# throttles); a failed bring-up exits nonzero and systemd retries
Restart=on-failure
RestartSec=120
# SIGTERM: engine keeps the SA + registration state for the next resume
KillMode=mixed
TimeoutStopSec=10

[Install]
WantedBy=multi-user.target