#!/bin/bash

#########################
#### USER EDITABLE ######
#########################

# You should hardcode the base URL for your raw repository files. Set the value
# of REPO_RAW_URL to your fork, replacing the `authorized_keys` file with your own.
# i.e., "https://raw.githubusercontent.com/<GH_USER>/<GH_REPO>/<GH_BRANCH>"
REPO_RAW_URL="https://git.krislamo.org/kris/bootstrap/raw/branch/main"
AUTH_KEY_FILE="/authorized_keys"

# Optional debianzfs install script, accessed with -z
DEBIANZFS="https://git.krislamo.org/kris/debianzfs/raw/branch/main/debianzfs.sh"
DEBIANZFS_BIN="/usr/local/bin/debianzfs"

##############################
######## STOP EDITING ########
##############################

# Root required
if [ $EUID -ne 0 ]; then
	echo "You must run this script as root"
	exit 1
fi

# Clean environment
unset BOOT_CYCLE
unset CDROM_REMOVE
unset ENABLE_SSH
unset GATEWAY_IP
unset NEW_HOSTNAME
unset IP
unset REPO
unset SSH_INSTALL
unset UPDATE_SYSTEM
unset ZFSINSTALL
unset DATE
unset CUR_HOSTNAME

# Options
while getopts ':bceg:h:i:r:suz' OPTION; do
	case "$OPTION" in
		b) BOOT_CYCLE=1;;
		c) CDROM_REMOVE=1;;
		e) ENABLE_SSH=1;;
		g) GATEWAY_IP="$OPTARG";;
		h) NEW_HOSTNAME="$OPTARG";;
		i) IP="$OPTARG";;
		r) REPO="$OPTARG";;
		s) SSH_INSTALL=1;;
		u) UPDATE_SYSTEM=1;;
		z) ZFSINSTALL=1;;
		?)
			echo "ERROR: Option not recognized"
			exit 1;;
	esac
done

# Allow override but use default repo if not set
[ -z "$REPO" ] && REPO="$REPO_RAW_URL"

# Get current date and hostname
DATE=$(date '+%Y%m%d')
CUR_HOSTNAME=$(hostname)

# Remove CD sources from sources list
if [ "$CDROM_REMOVE" -eq 1 ]; then
	echo "NOTICE: Backing up /etc/apt/sources.list => /etc/apt/sources.list.$DATE"
	sed -i."$DATE" '/deb cdrom/d' /etc/apt/sources.list
fi

# Upgrade system software
if [ "$UPDATE_SYSTEM" -eq 1 ]; then
	echo "NOTICE: Upgrading system"
	apt-get update
	apt-get upgrade -y
fi

# Install personal SSH keys under root and install the OpenSSH server
if [ "$SSH_INSTALL" -eq 1 ]; then
	# Does authorized_keys file already exist?
	if [ -f /root/.ssh/authorized_keys ]; then
		echo "ERROR: /root/.ssh/authorized_keys file already exists"
		exit 1
	fi

	echo "NOTICE: Installing root's authorized_keys and the OpenSSH server"
	mkdir -p /root/.ssh/
	chmod 700 /root/.ssh/
	wget "${REPO}${AUTH_KEY_FILE}" -O /root/.ssh/authorized_keys
	chmod 644 /root/.ssh/authorized_keys
	apt-get install openssh-server -y

	if [ "$ENABLE_SSH" -eq 1 ]; then
		echo "NOTICE: Enabling the OpenSSH server"
		systemctl start ssh
	fi
fi

# If IP is set, backup interfaces and configure static IP
if [ -n "$IP" ]; then
	if [ -z "$GATEWAY_IP" ]; then
		echo "ERROR: IP set without a GATEWAY address. See option -g"
		exit 1
	fi

	echo "NOTICE: Backing up network interfaces file and installing a new static one"
	sed -i."$DATE" "s/dhcp/static/g" /etc/network/interfaces
	if ! grep -q "address" /etc/network/interfaces; then
		echo "  address $IP" >> /etc/network/interfaces
		echo "  gateway $GATEWAY_IP" >> /etc/network/interfaces
	else
		echo "ERROR: Address already set"
		exit 1
	fi
fi

# Download DebianZFS script
if [ "$ZFSINSTALL" -eq 1 ]; then
	echo "NOTICE: Installing DebianZFS installation script"
	wget "$DEBIANZFS" -O "$DEBIANZFS_BIN"
	chmod u+x "$DEBIANZFS_BIN"
fi

# If NEW_HOSTNAME is set, configure new hostname and backup /etc/hosts
if [ -n "$NEW_HOSTNAME" ]; then
	hostnamectl set-hostname "$NEW_HOSTNAME"
	echo "NOTICE: Backing up /etc/hosts and setting new hostname to '$NEW_HOSTNAME'"
	sed -i."$DATE" "s/$CUR_HOSTNAME/$NEW_HOSTNAME/g" /etc/hosts
fi

# Restart
if [ "$BOOT_CYCLE" -eq 1 ]; then
	echo "NOTICE: Restarting the machine in 10 seconds..."
	sleep 9
	echo "NOTICE: Restarting!"
	sleep 1
	systemctl reboot
fi