#!/bin/sh

# Some Global Variables

ssh_authorized_keys_path='/root/.ssh/authorized_keys'
ssh_config_path='/etc/ssh/ssh_config'
sshd_config_path='/etc/ssh/sshd_config'
etc_resolv_path='/etc/resolv.conf'


# Functions

get_distro() {
	OS=$(cat /etc/*release | grep ID | head -1 | cut -c 4-)
	echo $OS
}

setup_ssh() {
	tput setaf 2; tput bold; echo "Setting up SSH"; tput sgr0;

	mkdir -p $(dirname $ssh_authorized_keys_path)
	touch $ssh_authorized_keys_path

	if ! grep -q "PasswordAuthentication no" $sshd_config_path; then
		echo "PasswordAuthentication no" >> $sshd_config_path
	fi

	if ! grep -q "PermitRootLogin yes" $sshd_config_path; then
		echo "PermitRootLogin yes" >> $sshd_config_path
	fi

	# TODO: Make sure to replace the following address with http://metadata
	# whenever we got http://metadata resolving to url work successfully.

	metadata=$(curl -s http://metadata)

	echo "$metadata" | jq -r '.["ssh-keys"] | .[]' > ssh-key-list.txt
	while read ssh_key; do
		if ! grep -q "$ssh_key" $ssh_authorized_keys_path; then
			echo $ssh_key >> $ssh_authorized_keys_path
		fi

	done  < ssh-key-list.txt
	rm -f ssh-key-list.txt

	service -q sshd restart
}

grow_partition() {
	tput setaf 2; tput bold; echo "Growing Partition"; tput sgr0;

	# TODO: Try to replace the growpart to parted
	sh growpart -q /dev/vda 3 > /dev/null;
}

make_script_verbose() {
	# Show output of this script
	if [[ ! -e /etc/conf.d/local ]] && ! grep -q "rc_verbose=yes" /etc/conf.d/local; then
		echo "rc_verbose=yes" >> /etc/conf.d/local
	fi
}

setup_dns() {
	tput setaf 2; tput bold; echo "Setting up DNS"; tput sgr0;

	# Check if rdnssd is installed, if not put Google's DNS
	# into /etc/resolv.conf and install rdnssd for the next time
	if ! apk list | grep -q ndisc6; then
		echo "nameserver 2001:4860:4860::8888" >> $etc_resolv_path
		echo "nameserver 2001:4860:4860::8844" >> $etc_resolv_path
		echo "nameserver 8.8.8.8" >> $etc_resolv_path
		echo "nameserver 8.8.4.4" >> $etc_resolv_path	
	fi	
}

# Main Code Starts here

# Change dir to current dir
cd "$(dirname "$0")"

make_script_verbose

setup_dns

# Initial Package Installation
if [[ $(get_distro) = "alpine" ]]; then
	tput setaf 2; tput bold; echo "Installing/Updating/Upgrading Packages"; tput sgr0;

	edge_package_flags='--update-cache --repository http://dl-3.alpinelinux.org/alpine/edge/testing/ --allow-untrusted'
	
	apk update -q
	apk upgrade
	apk add -q ndisc6 $edge_package_flags
	apk add -q openssh-server sfdisk util-linux jq curl ncurses
else
	echo "Unsupported OS"
	exit 1
fi

rc-update -q add rdnssd
service -q rdnssd start

setup_ssh

grow_partition