#!/usr/bin/env bash

set -eo pipefail
cd "$(dirname "$0")"

if ! command -v nix-build &> /dev/null
then
	echo "Nix installation could not be found. Please follow the instructions linked below."
	echo "https://nixos.org/manual/nix/unstable/installation/installing-binary.html#multi-user-installation"
	exit
fi

mode="${1:-switch}"
host="${2:-nuc}"
target="${3:-c3h@$host.c3h}"

if ! [ -d "hosts/$host" ]
then
	echo "Host $host does not exist. Choose from:"
	ls hosts
	exit
fi

echo "deploying $host to $target"
sleep 1

tmp=$(mktemp -d)
trap 'rm -rf "$tmp"' EXIT
sources="$tmp/sources"
cp -r $(nix-build nix/sources-dir.nix --no-out-link) $tmp/sources

set -x
system_drv=$(nix-instantiate "<nixpkgs/nixos>" -A config.system.build.toplevel -I $sources -I "nixos-config=$PWD/hosts/$host/configuration.nix")
nix-copy-closure --to $target $system_drv
system=$(ssh $target "nix-store --realise $system_drv")
ssh $target "sudo nix-env -p /nix/var/nix/profiles/system -i $system && sudo /nix/var/nix/profiles/system/bin/switch-to-configuration $mode"