#!/bin/sh

# Build installers 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 'makeself' >'/dev/null'
then makeself='makeself'
elif type 'makeself.sh' >'/dev/null'
then makeself='makeself.sh'
else
	echo >&2 'This script requires makeself: https://makeself.io'
	exit 1
fi

rel_name='ejabberd'
rel_vsn=$(git describe | sed -e 's/-g.*//' -e 's/-/./' | tr -d '[:space:]')
code_path="/opt/$rel_name-$rel_vsn"
data_path="/opt/$rel_name"
conf_path="$data_path/conf"
pem_file="$conf_path/server.pem"
url='https://docs.ejabberd.im/admin/upgrade/#specific-version-upgrade-notes'
tmp_dir=$(mktemp -d "/tmp/.$rel_name.XXXXXX")

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

create_setup_script()
{
	local dir="$1"
	local tarball="$2"

	cat >"$dir/setup" <<-EOF
	#!/bin/sh

	set -e
	set -u

	export PATH='/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin'

	user_agrees()
	{
		local question="\$*"

		if [ -t 0 ]
		then
			read -p "\$question (y/n) [n] " response
			response="\$(printf '%s' "\$response" |
			             tr '[:upper:]' '[:lower:]')"
			if [ "\$response" = 'y' ] || [ "\$response" = 'yes' ]
			then return 0
			else return 1
			fi
		else # Assume 'yes' if not running interactively.
			return 0
		fi
	}

	if [ \$(id -u) != 0 ]
	then
		echo >&2 'The installer must be run with superuser privileges.'
		exit 1
	fi

	if [ -e '/run/systemd/system' ]
	then is_systemd=true
	else is_systemd=false
	fi
	if [ -e '$data_path' ]
	then is_upgrade=true
	else is_upgrade=false
	fi
	if id -u '$rel_name' >'/dev/null' 2>&1
	then user_exists=true
	else user_exists=false
	fi

	echo 'The following installation paths will be used:'
	echo '- $code_path'
	if [ \$is_upgrade = true ]
	then echo "- $data_path (existing files won't be modified)"
	else echo '- $data_path'
	fi
	if [ \$is_systemd = true ]
	then echo '- /etc/systemd/system/$rel_name.service'
	fi
	if [ \$user_exists = false ]
	then echo 'The $rel_name user is going to be created.'
	fi
	if [ \$is_systemd = true ] && [ \$is_upgrade = false ]
	then echo 'The $rel_name service is going to be enabled and started.'
	fi
	if ! user_agrees 'Install $rel_name $rel_vsn now?'
	then
		echo 'Aborting installation.'
		exit 1
	fi

	if [ \$user_exists = false ]
	then useradd -r -d '$data_path' '$rel_name'
	fi

	host=\$(hostname --fqdn 2>'/dev/null' || :)
	if [ -z "\$host" ]
	then host='localhost'
	fi

	tar --skip-old-files -C "\$(dirname '$code_path')" -xf '$tarball'
	chown -R -h 'root:root' '$code_path'
	chown 'root:$rel_name' '$code_path/lib/epam-'*'/priv/bin/epam'
	chmod '4750' '$code_path/lib/epam-'*'/priv/bin/epam'
	if [ \$is_upgrade = false ]
	then
		sed -i "s/ - localhost$/ - \$host/" '$conf_path/$rel_name.yml'
		openssl req -x509 \
		            -batch \
		            -nodes \
		            -newkey rsa:4096 \
		            -keyout '$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 [ \$is_systemd = true ]
	then
		cp '$code_path/bin/$rel_name.service' '/etc/systemd/system/'
		systemctl -q daemon-reload
		if [ \$is_upgrade = false ]
		then systemctl -q --now enable '$rel_name'
		fi
	elif [ \$is_upgrade = false ]
	then
		echo 'You might want to install an init script (see the'
		echo '$code_path/bin directory for an example).'
	fi
	echo '$rel_name $rel_vsn has been installed successfully.'

	if [ \$is_upgrade = true ]
	then
		echo 'Please check the following web site for upgrade notes:'
		echo
		echo '$url'
		echo
		echo 'If everything looks fine, restart the $rel_name service.'
	fi
	EOF
	chmod +x "$dir/setup"
}

for arch in $architectures
do
	tar_name="$rel_name-$rel_vsn-linux-$arch.tar"
	tgz_name="$tar_name.gz"
	installer_name="$rel_name-$rel_vsn-$iteration-linux-$arch.run"

	test -e "$tgz_name" || tools/make-binaries
	echo "$myself: Putting together installer for $arch ..."
	gzip -c -d <"$tgz_name" >"$tmp_dir/$tar_name"
	create_setup_script "$tmp_dir" "$tar_name"
	"$makeself" "$tmp_dir" "$installer_name" "$rel_name $rel_vsn" './setup'
	find "$tmp_dir" -mindepth 1 -delete
done
echo "$myself: Created installers successfully."