#!/bin/bash
set -xeuo pipefail

opdir="$1"

common_ssh_cfg_path="$HOME/diyvpn_sshconfig"
diyvpn_cfg="$HOME/.config/diyvpn/servers"

generate() {
		local cfgpath opdir name server_ssh_cfg idle_timeout listen_port
		cfgpath="$1"
		opdir="$2"
		name=$(basename "$cfgpath")
		server_ssh_cfg="$cfgpath"/ssh_config # TODO validate
		source "$cfgpath/config.rc"

		idle_timeout="${IDLE_TIMEOUT:-10min}"
		listen_port="${LISTEN_PORT:?LISTEN_PORT should be set}"

		cat > "$opdir/diyvpnssh-$name.service" <<-EOF
		[Unit]
		Description=ssh to $name
		StopWhenUnneeded=yes

		[Service]
		Type=notify
		NotifyAccess=all

		Restart=no # TODO change to yes
		RuntimeDirectory=diyvpn-$name
		Environment=SSH_CFG_PATH=$server_ssh_cfg
		ExecStart=ssh -F $common_ssh_cfg_path  default
		EOF

		cat > "$opdir/diyvpnact-$name.service" <<-EOF
		[Unit]
		Requires=diyvpnssh-$name.service
		After=diyvpnssh-$name.service
		BindsTo=diyvpnssh-$name.service

		[Service]
		ExecStart=/usr/lib/systemd/systemd-socket-proxyd --exit-idle-time=$idle_timeout %t/diyvpn-$name/sock
		EOF

		cat > "$opdir/diyvpnact-$name.socket" <<-EOF
		[Unit]
		Description=Socket activation for diyvpn

		[Socket]
		ListenStream=$listen_port

		[Install]
		WantedBy=sockets.target
		EOF
}

for server in "$diyvpn_cfg"/*
do
		(generate "$server" "$opdir")
done