export _nix_system_config="git+https://git.voronind.com/voronind/nixos.git"

# Rebuild system.
# Optionally force the hostname.
# Usage: nixos_rebuild [HOSTNAME]
function nixos_rebuild() {
	local target="${1}"
	[[ "${target}" = "" ]] && target="${HOSTNAME}"

	nixos-rebuild boot --flake "${_nix_system_config}#${target}" --refresh ${@}
}

# Rebuild and switch system.
# Optionally force the hostname.
# Usage: nixos_switch [HOSTNAME]
function nixos_switch() {
	local target="${1}"
	[[ "${target}" = "" ]] && target="${HOSTNAME}"

	nixos-rebuild switch --flake "${_nix_system_config}#${target}" --refresh ${@}
}

# Spawn shell with specified nix environment.
# Uses flake.nix in current dir by default.
# Usage: nix_shell [NAME]
function nix_shell() {
	local target="${1}"
	[[ "${target}" = "" ]] && target="default"

	# Create Nix GC root in .NixRoot{NAME}.
	nix build ".#devShells.${NIX_CURRENT_SYSTEM}.${target}" -o ".NixRoot${target^}"

	NIX_SHELL="${target}" nix develop ".#devShells.${NIX_CURRENT_SYSTEM}.${target}"
}
alias shell="nix_shell"

# Spawn temporary nix-shell with specified packages.
# Usage: nix_tmpshell <PACKAGES>
function nix_tmpshell() {
	local IFS=$'\n'
	local input=("${@}")
	local pkgs=()
	local tag="${NIX_SHELL}"

	if [[ "${input}" = "" ]]; then
		help nix_tmpshell
		return 2
	fi

	[[ "${tag}" = "" ]] && tag="${1}"

	for pkg in ${input[@]}; do
		pkgs+=("nixpkgs#${pkg}")
	done

	NIX_SHELL="${tag}" NIXPKGS_ALLOW_UNFREE=1 nix shell --impure ${pkgs[@]}
}
alias tmpshell="nix_tmpshell"

# Build live image.
function nixos_live() {
	nix build "${_nix_system_config}#nixosConfigurations.live.config.system.build.isoImage" --refresh ${@}
}

# List nixos generations.
function nixos_generations() {
	nix-env -p /nix/var/nix/profiles/system --list-generations
}

# Switch nix-on-droid.
function nixdroid_switch() {
	nix-on-droid switch --flake "${_nix_system_config}" ${@}
}

# Autocomplete with available hosts.
function _comp_hosts() {
	local IFS=$'\n'
	local targets=($(ls ~/.config/linux/system/host/))

	_autocomplete_first ${targets[@]}
}

complete -F _comp_hosts nix_switch nix_rebuild