#!/usr/bin/env nix-shell
#! nix-shell -i bash
#! nix-shell -p bash nixos-install-tools

set -euo pipefail

# Parse arguments
function help {
    echo "Usage: $0 -e"
    echo
    echo "Options:"
    echo "  -h: Display this help message."
    echo "  -e: Erase the disk. This can be used in case the wanted partition scheme doesn't match."
}

disko_mode=mount
while getopts "e" OPTION
do
    case "$OPTION" in
        h)
            help
            exit 0
            ;;
        e)
            disko_mode=disko
            ;;
        ?)
            help
            exit 2
            ;;
    esac
done
shift "$(($OPTIND -1))"

if [ "$#" -gt 0 ]
then
    help
    exit 2
fi

set -x

# Add channels to root user, as nixos-install uses those.
# Not great, but fixable with flakes I guess
sudo ./add_channels.sh

# Format or mount disk
sudo nix --extra-experimental-features nix-command --extra-experimental-features flakes run github:nix-community/disko -- --mode $disko_mode ./pindakaas_disko.nix

# Generate hardware-config.nix
sudo nixos-generate-config --no-filesystems --root /mnt
# --no-filesystems because they are imported via disko

# Plug system configuration into this git repo
sudo mkdir -p /mnt/etc/nixos
echo "{ ... }: { imports = [ ./hardware-configuration.nix /home/geoffrey/.config/dotfiles/pindakaas.nix ]; }" | sudo tee /mnt/etc/nixos/configuration.nix > /dev/null
# Everything there should be covered by (and conflicts with) the repo anyways.

# Install NixOS! Or create a new generation.
sudo nixos-install

# Install dotfiles. Actually not needed by nixos-install since it doesn't rewrite global paths to /mnt.
# Without it no nixos-rebuild from the system itself once installed though.
# Should probably be replaced with something like git-sync
# sudo mkdir -p /mnt/home/geoffrey/.config/
# sudo cp -a ../dotfiles /mnt/home/geoffrey/.config/
# sudo chown geoffrey:geoffrey /mnt/home/geoffrey -R

# Signal we're done!
# Although it might ask for passwords beforehand, so not sure it's really useful
echo