#!/usr/bin/env bash

set -euo pipefail

hostname=""
device=""
no_confirm=""

while [[ $# -gt 0 ]]; do
  case $1 in
  --hostname)
    hostname=$2
    shift
    shift
    ;;
  --device)
    device=$2
    shift
    shift
    ;;
  --no-confirm)
    no_confirm=1
    shift
    ;;
  *)
    echo "unknown option: $1"
    exit 1
    ;;
  esac
done

echo ""
echo "  This is clerie's nixfiles auto install for new hosts"
echo "  It will do dangerous things like format your disk"
echo "  So be careful when using it"
echo ""

if [[ -z $no_confirm ]]; then
  read -e -r -p "Continue?" confirm
  echo "$confirm" > /dev/null
fi

if [[ -z $hostname ]]; then
  fallback_hostname="host${RANDOM}"
  read -e -r -p "Hostname [$fallback_hostname]: " hostname
  if [[ -z $hostname ]]; then
    hostname=$fallback_hostname
  fi
fi

echo "[I] Deploying with hostname ${hostname}"

if [[ -z $device ]]; then
  device="/dev/sda"
  while true; do
    read -e -r -p "Disk [$device]: " dev
    if [[ -z $dev ]]; then
      dev=$device
    fi

    if [[ -b $dev ]]; then
      device=$dev
      break
    else
      echo "[E] Disk $dev does not exist"
    fi
  done
fi

echo "[I] Deploying on disk ${device}"

if [[ -z $no_confirm ]]; then
  read -e -r -p "Deploy host?" deploy
  echo "$deploy" > /dev/null
fi

echo "[I] Formatting disk"

if [[ ! -b $device ]]; then
  echo "Disk $device does not exist"
  exit 1
fi

echo "[I] Using ${device}"

parted --script "$device" mklabel gpt
parted --script "$device" disk_set pmbr_boot on

parted --script "$device" mkpart boot 0% 512M
parted --script "$device" set 1 bios_grub on

parted --script "$device" mkpart root 512M 100%

echo "[I] Creating file system"

mkfs.ext4 -F "${device}2"

echo "[I] Mount file system"

mount "${device}2" /mnt

echo "[I] Generate NixOS configuration"

nixfiles-generate-config --root /mnt --hostname "${hostname}"

sed -i "s~# boot\.loader\.grub\.device = \"/dev/sda\";~boot\.loader\.grub\.device = \"${device}\";~g" "/mnt/etc/nixos/hosts/${hostname}/configuration.nix"

echo "[I] Install NixOS"

nixos-install --flake "/mnt/etc/nixos#${hostname}" --root /mnt --no-root-password