#!/bin/sh

# Build DEB and RPM packages for Linux/x64 and Linux/arm64.
#
# Author: Holger Weiss <holger@zedat.fu-berlin.de>.
#
# Copyright (c) 2022 ProcessOne, SARL.
# All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

set -e
set -u

myself=${0##*/}
architectures='x64 arm64'
iteration=1

usage()
{
	echo >&2 "Usage: $myself [-i <iteration>]"
	exit 2
}

while getopts i: opt
do
	case $opt in
	i)
		iteration="$OPTARG"
		;;
	\?)
		usage
		;;
	esac
done
shift $((OPTIND - 1))

if ! [ -e 'mix.exs' ] || ! [ -e "tools/$myself" ]
then
	echo >&2 "Please call this script from the repository's root directory."
	exit 2
elif [ $# -ne 0 ]
then
	usage
fi
if ! type fpm >'/dev/null'
then
	echo >&2 'This script requires fpm: https://fpm.readthedocs.io'
	exit 1
fi

rel_name='ejabberd'
rel_vsn=$(git describe --tags | sed -e 's/-g.*//' -e 's/-/./' | tr -d '[:space:]')
conf_dir="/opt/$rel_name/conf"
pem_file="$conf_dir/server.pem"
tmp_dir=$(mktemp -d "/tmp/.$myself.XXXXXX")

trap 'rm -rf "$tmp_dir"' INT TERM EXIT
umask 022

create_scripts()
{
	local dir="$1"

	cat >"$dir/before-install" <<-EOF
	if ! getent group '$rel_name' >'/dev/null'
	then groupadd -r '$rel_name'
	fi
	if ! getent passwd '$rel_name' >'/dev/null'
	then useradd -r -m -d '/opt/$rel_name' -g '$rel_name' '$rel_name'
	fi
	if ! [ -e '$pem_file' ]
	then
		if ! [ -e '/opt/$rel_name' ] # Huh?
		then install -o '$rel_name' -g '$rel_name' -m 750 -d '/opt/$rel_name'
		fi
		if ! [ -e '$conf_dir' ]
		then install -o '$rel_name' -g '$rel_name' -m 750 -d '$conf_dir'
		fi
		host=\$(hostname --fqdn 2>'/dev/null' || :)
		if [ -z "\$host" ]
		then host='localhost'
		fi
		openssl req -x509 \
		            -batch \
		            -nodes \
		            -newkey rsa:4096 \
		            -keyout '$pem_file' \
		            -out '$pem_file' \
		            -days 3650 \
		            -subj "/CN=\$host" >'/dev/null' 2>&1 || :
		if [ -e '$pem_file' ]
		then chown '$rel_name:$rel_name' '$pem_file'
		else echo 'Failed to create a TLS certificate for ejabberd.' >&2
		fi
	fi
	if ! [ -e '/opt/$rel_name/database' ]
	then install -o '$rel_name' -g '$rel_name' -m 750 -d '/opt/$rel_name/database'
	fi
	if ! [ -e '/opt/$rel_name/logs' ]
	then install -o '$rel_name' -g '$rel_name' -m 750 -d '/opt/$rel_name/logs'
	fi
	EOF

	cat >"$dir/after-install" <<-EOF
	host=\$(hostname --fqdn 2>'/dev/null' || :)
	if [ -n "\$host" ]
	then sed -i "s/ - localhost$/ - \$host/" '$conf_dir/$rel_name.yml'
	fi
	chown 'root:$rel_name' '/opt/$rel_name-$rel_vsn/lib/epam-'*'/priv/bin/epam'
	chmod '4750' '/opt/$rel_name-$rel_vsn/lib/epam-'*'/priv/bin/epam'
	chown -R -h '$rel_name:$rel_name' '/opt/$rel_name'
	chmod 'o-rwx' '/opt/$rel_name/'*
	EOF

	cat >"$dir/after-upgrade" <<-EOF
	chown 'root:$rel_name' '/opt/$rel_name-$rel_vsn/lib/epam-'*'/priv/bin/epam'
	chmod '4750' '/opt/$rel_name-$rel_vsn/lib/epam-'*'/priv/bin/epam'
	EOF

	cat >"$dir/after-remove" <<-EOF
	rm -f '/opt/$rel_name/.erlang.cookie'
	if getent passwd '$rel_name' >'/dev/null'
	then userdel '$rel_name'
	fi
	if getent group '$rel_name' >'/dev/null'
	then groupdel '$rel_name'
	fi
	EOF
}

package_architecture()
{
	local target="$1"
	local host_target="$(uname -m)-$target"

	case $host_target in
	x86_64-x64)
		printf 'native'
		;;
	x86_64-arm64)
		printf 'arm64'
		;;
	*)
		echo >&2 "Unsupported host/target combination: $host_target"
		exit 1
		;;
	esac
}

make_package()
{
	local output_type="$1"
	local architecture="$(package_architecture "$2")"
	local work_dir="$3"
	local include_dirs="$4"

	cd "$work_dir" # FPM's "--chdir" option doesn't work (as I'd expect).
	fpm --output-type "$output_type" \
	    --input-type 'dir' \
	    --name "$rel_name" \
	    --version "$rel_vsn" \
	    --iteration "$iteration" \
	    --license 'GPL-2+' \
	    --category 'net' \
	    --provides 'stun-server' \
	    --provides 'turn-server' \
	    --provides 'xmpp-server' \
	    --no-depends \
	    --no-auto-depends \
	    --deb-maintainerscripts-force-errorchecks \
	    --deb-systemd-enable \
	    --deb-systemd-auto-start \
	    --deb-systemd "./$rel_name.service" \
	    --deb-init "./$rel_name" \
	    --rpm-init "./$rel_name" \
	    --config-files "$conf_dir" \
	    --directories "/opt/$rel_name" \
	    --directories "/opt/$rel_name-$rel_vsn" \
	    --architecture "$architecture" \
	    --maintainer 'ejabberd Maintainers <ejabberd@process-one.net>' \
	    --vendor 'ProcessOne, SARL' \
	    --description 'Robust and scalable XMPP/MQTT/SIP server.' \
	    --url 'https://ejabberd.im' \
	    --before-install './before-install' \
	    --after-install './after-install' \
	    --before-upgrade './before-install' \
	    --after-upgrade './after-upgrade' \
	    --after-remove './after-remove' \
	    $include_dirs
	cd "$OLDPWD"
}

for arch in $architectures
do
	tar_name="$rel_name-$rel_vsn-linux-gnu-$arch.tar.gz"
	arch_dir="$tmp_dir/$arch"
	opt_dir="$arch_dir/opt"
	etc_dir="$arch_dir/etc"
	bin_dir="$arch_dir/usr/sbin"
	dst_dir="$opt_dir/$rel_name-$rel_vsn"

	test -e "$tar_name" || tools/make-binaries

	echo "$myself: Putting together DEB and RPM packages for $arch ..."

	mkdir -p "$opt_dir" "$bin_dir"
	tar -C "$opt_dir" -xzf "$tar_name"

	cat >"$bin_dir/${rel_name}ctl" <<-EOF
	#!/bin/sh
	exec '/opt/$rel_name-$rel_vsn/bin/${rel_name}ctl' "\$@"
	EOF
	chmod +x "$bin_dir/${rel_name}ctl"

	mkdir -p "$etc_dir/systemd/system"
	mv "$dst_dir/bin/$rel_name.service" "$etc_dir/systemd/system"
	mv "$dst_dir/bin/$rel_name.init" "$arch_dir/$rel_name"
	sed -i \
	    "s|opt/$rel_name-$rel_vsn/bin/${rel_name}ctl|usr/sbin/${rel_name}ctl|g" \
	    "$etc_dir/systemd/system/$rel_name.service" "$arch_dir/$rel_name"

	create_scripts "$arch_dir"
	make_package 'rpm' "$arch" "$arch_dir" './opt ./usr ./etc'
	mv "$etc_dir/systemd/system/$rel_name.service" "$arch_dir"
	rm -r "$etc_dir"
	make_package 'deb' "$arch" "$arch_dir" './opt ./usr'
	mv "$arch_dir/$rel_name"?$rel_vsn*.??? .
done
echo "$myself: Created DEB and RPM packages successfully."