#!/usr/bin/env bash
set -e

usage="Usage: $(basename $0) [OPTIONS]

Options:
  -f, --fresh              Remove old content in the nixstore (good for debugging)
  -b, --bootloader         Reinstall the bootloader
  -h, --help               Show this message (^_^)"

# delete all cached entries
# to make the system from scratch
collect_garbage () {
	sudo nix-collect-garbage --delete-old
}

rebuild_flake () {
	# make sure all changes are visible to nixos
	git add . --verbose
	if [ "$1" = "reinstall-bootloader" ]; then
		sudo nixos-rebuild switch --flake . --install-bootloader
	else	
		sudo nixos-rebuild switch --flake .
		#nixos-rebuild build --flake .# --cores 8 -j 1
	fi
}

# check which flags were given
flag_fresh=false
flag_bootloader=false
for flag in "$@"; do
	case "$flag" in
		-f|--fresh) 
			flag_fresh=true ;;
		-b|--bootloader) 
			flag_bootloader=true ;;
		-h|--help)
			echo "$usage"
			exit 0 ;;
		*)
			echo "[!] Unknown flag \"$flag\""
			exit 1 ;;
	esac
done

# delete cached items in nixstore
if [ "$flag_fresh" = true ]; then
	collect_garbage
	exit 0
fi

# nixos-rebuild switch ...
if [ "$flag_bootloader" = true ]; then
	collect_garbage
	rebuild_flake "reinstall-bootloader"
else
	rebuild_flake
fi