pkgs/nixfiles: expose nixfiles-generate-config as pkg

pkgs/nixfiles/nixfiles-generate-config.nix

@@ -0,0 +1,10 @@
+{ pkgs, ... }:
+
+pkgs.writeShellApplication {
+  name = "nixfiles-generate-config";
+  text = builtins.readFile ./nixfiles-generate-config.sh;
+  runtimeInputs = with pkgs; [
+    git
+  ];
+  checkPhase = "";
+}

pkgs/nixfiles/nixfiles-generate-config.sh

@@ -0,0 +1,46 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+hostname=$(hostname --short)
+root=""
+ngcroot=""
+
+while [[ $# -gt 0 ]]; do
+case $1 in
+--root)
+  root=$2
+  ngcroot="--root ${root}"
+  shift
+  shift
+  ;;
+--hostname)
+  hostname=$2
+  shift
+  shift
+  ;;
+*)
+  echo "unknown option: $1"
+  exit 1
+  ;;
+esac
+done
+
+mkdir -p "${root}/etc/nixos"
+
+if [[ ! -d "${root}/etc/nixos/.git" ]]; then
+git clone https://git.clerie.de/clerie/nixfiles.git "${root}/etc/nixos"
+git -C "${root}/etc/nixos" remote set-url origin gitea@git.clerie.de:clerie/nixfiles.git
+fi
+
+mkdir -p "${root}/etc/nixos/hosts/${hostname}"
+
+nixos-generate-config ${ngcroot} --dir "${root}/etc/nixos/hosts/${hostname}"
+
+# make sure host is added to flake.nix
+if ! grep -q "${hostname} = generateNixosSystem \"${hostname}\";" "${root}/etc/nixos/flake.nix"; then
+sed -i "s/\(\s*\)_iso = generateNixosSystem \"_iso\";/\1${hostname} = generateNixosSystem \"${hostname}\";\n&/g" "${root}/etc/nixos/flake.nix"
+fi
+
+sed -i "s/\%HOSTNAME\%/${hostname}/g" "${root}/etc/nixos/hosts/${hostname}/configuration.nix"
+
+git -C "${root}/etc/nixos" add "${root}/etc/nixos/hosts/${hostname}"