#!/bin/sh -e
#
# 2014-2017 Steven Armstrong (steven-cdist at armstrong.cc)
# 2014 Nico Schottelius (nico-cdist at schottelius.org)
# 2019 Dennis Camera (dennis.camera at ssrq-sds-fds.ch)
#
# This file is part of cdist.
#
# cdist is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# cdist is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with cdist. If not, see <http://www.gnu.org/licenses/>.
#

os=$(cat "$__global/explorer/os")
name_running=$(cat "$__global/explorer/hostname")
name_config=$(cat "$__object/explorer/persistent_hostname")
has_hostnamectl=$(cat "$__object/explorer/has_hostnamectl")


if [ -f "$__object/parameter/name" ]; then
    name_should="$(cat "$__object/parameter/name")"
else
    case $os
    in
        # RedHat-derivatives and BSDs
        centos|fedora|redhat|scientific|freebsd|netbsd|openbsd)
            # Hostname is FQDN
            name_should="${__target_host}"
        ;;
        *)
            # Hostname is only first component of FQDN
            name_should="${__target_host%%.*}"
        ;;
    esac
fi

################################################################################
# Check if the hostname is already correct
#
if [ "$name_running" = "$name_should" ] \
  && [ -z "$name_config" -o "$name_config" = "$name_should" ]
then
    exit 0
fi

################################################################################
# Setup hostname
#
echo 'changed' >>"$__messages_out"


# First try to set the hostname using hostnamectl, if available.
if [ -n "$has_hostnamectl" ]; then
    # Allow hostnamectl to fail silently.
    # Who the fuck invented a tool that needs dbus to set the hostname anyway…

    # NOTE: We write the static hostname to /etc/hostname first in case
    #       hostnamectl fails. Fallback-code below will then adjust the running
    #       hostname below.
    echo "echo '$name_should' >/etc/hostname"

    echo "hostnamectl set-hostname '$name_should' && exit 0"
fi

# Use the good old way to set the hostname. Also if hostnamectl fails.
case $os
in
    alpine|archlinux|debian|devuan|ubuntu)
        echo "echo '$name_should' >/etc/hostname"
        echo "hostname -F /etc/hostname"
    ;;
    coreos|openbmc-phosphor)
        # NOTE: systemd-only distros have the hostname already written above.
        #       But since hostamectl failed, we update the running hostname
        #       manually.
        echo "hostname -F /etc/hostname"
        ;;
    gentoo)
        # NOTE: Writing the hostname to file is done in the manifest for OpenRC.
        #       For systemd hostnamectl should take care of that.
        echo "hostname '$name_should'"
    ;;
    macosx)
        echo "scutil --set HostName '$name_should'"
    ;;
    suse)
        # We write into /etc/HOSTNAME for backwards-compatibility.  Modern SuSE
        # has hostnamectl anyway and symlinks /etc/HOSTNAME to /etc/hostname.
        echo "echo '$name_should' >/etc/HOSTNAME"
        echo 'hostname -F /etc/HOSTNAME'
    ;;
    centos|fedora|freebsd|netbsd|openbsd|redhat|scientific)
        # NOTE: Writing the hostname to file is done in the manifest.
        echo "hostname '$name_should'"
    ;;
    *)
        echo "echo 'Unsupported OS: $os' >&2; exit 1"
    ;;
esac