#!/bin/bash
set -uo pipefail


################################################
# Initialize script environment

# Find the directory this script is stored in. (from: http://stackoverflow.com/questions/59895)
function get_source_dir() {
	local source="${BASH_SOURCE[0]}"
	while [[ -h $source ]]
	do
		local tmp
		tmp="$(cd -P "$(dirname "${source}")" && pwd)"
		source="$(readlink "${source}")"
		[[ $source != /* ]] && source="${tmp}/${source}"
	done

	echo -n "$(realpath "$(dirname "${source}")")"
}

GENTOO_INSTALL_REPO_DIR="$(get_source_dir)"
export GENTOO_INSTALL_REPO_DIR
export GENTOO_INSTALL_REPO_SCRIPT_ACTIVE=true

# shellcheck source=./scripts/utils.sh
source "$GENTOO_INSTALL_REPO_DIR/scripts/utils.sh"

# Remember actual config file path
CONFIG_FILE="$(realpath "${1-"gentoo.conf"}" 2>/dev/null)"
RELA_CONFIG_FILE="$(realpath --relative-to="$(pwd)" "$CONFIG_FILE" 2>/dev/null)"

# Check if help is requested
while [[ $# -gt 0 ]]; do
	case "$1" in
		""|"help"|"--help"|"-help"|"-h")
			echo "Usage: $0 [config]"
			echo "Starts the gentoo configurator. If no file is given, it defaults to 'gentoo.conf'."
			echo "If the file doesn't exist, the configurator loads default values, otherwise, the"
			echo "the configuration is loaded into the configurator."
			exit 0
			;;
	esac
	shift
done

# TODO check install dialog
echo "Please install dialog on your system to use the configurator"

# Wrap dialog in two functions to prevent it from cluttering stderr.
function dialog_wrapper() { dialog_out=$(command dialog --colors "$@" 3>&2 2>&1 1>&3 3>&-); }
function dialog() { dialog_wrapper "$@" 2>&1; }


################################################
# Configuration helper functions

function get_timezone() {
	local file
	if file="$(readlink /etc/localtime)"; then
		# /etc/localtime is a symlink as expected
		local timezone
		timezone=${file#*zoneinfo/}
		if [[ $timezone == "$file" ]]; then
			# not pointing to expected location or not Region/City
			echo "Europe/London"
		else
			echo "$timezone"
		fi
	else
		# compare files by contents
		find /usr/share/zoneinfo -type f -exec cmp -s {} /etc/localtime \; -print \
			| sed -e 's,.*/zoneinfo/,,' \
			| head -1
	fi
}

function get_default_keymap() {
	local keymap
	keymap="$(grep KEYMAP /etc/vconsole.conf 2>/dev/null || echo "KEYMAP=us")"
	keymap="${keymap#KEYMAP=}"

	local map
	for map in "${ALL_KEYMAPS[@]}"; do
		if [[ $map == "$keymap" ]]; then
			echo -n "${keymap}"
			return
		fi
	done

	# Fallback to us
	echo -n "us"
}

function get_all_keymaps() {
	ALL_KEYMAPS=()
	local map
	for map in $(find /usr/share/keymaps/ /usr/share/kbd/keymaps/ -type f -iname '*.map.gz' -printf "%f\n" 2>/dev/null | sort -u); do
		ALL_KEYMAPS+=("${map%%.map.gz}")
	done
}

function get_all_timezones() {
	readarray -t ALL_TIMEZONES < <(find /usr/share/zoneinfo -type f -printf "%P\n" | sort -u)
}

function get_supported_locales() {
	if [[ -e /usr/share/i18n/SUPPORTED ]]; then
		echo /usr/share/i18n/SUPPORTED
	else
		echo "$GENTOO_INSTALL_REPO_DIR/contrib/i18n_supported"
	fi
}

function recalculate_locales() {
	LOCALES=""
	N_LOCALES=0

	local selected_index_list="$SELECTED_LOCALES"
	local next_selected
	next_selected="${selected_index_list%% *}"
	selected_index_list="${selected_index_list#* }"

	local i=0
	for item in "${SUPPORTED_LOCALES[@]}"; do
		if [[ "$i" == "$next_selected" ]]; then
			LOCALES="$LOCALES"$'\n'"$item"
			next_selected="${selected_index_list%% *}"
			selected_index_list="${selected_index_list#* }"
			((++N_LOCALES))
		fi
		((++i))
	done

	LOCALES="${LOCALES:1}"
}

function define_disk_configuration_function() {
	cat << EOF
function disk_configuration() {
	$* ;
}
EOF
}

function define_swap() {
	if [[ $PARTITIONING_USE_SWAP == "true" ]]; then
		echo -n "${PARTITIONING_SWAP@Q}"
	else
		echo -n "false"
	fi
}

function define_disk_layout() {
	case "$PARTITIONING_SCHEME" in
		"classic_single_disk") define_disk_configuration_function "create_classic_single_disk_layout swap=$(define_swap) type=${PARTITIONING_BOOT_TYPE@Q} luks=${PARTITIONING_USE_LUKS@Q} root_fs=${PARTITIONING_ROOT_FS@Q}" "${PARTITIONING_DEVICE@Q}" ;;
		"zfs_centric")         define_disk_configuration_function "create_zfs_centric_layout swap=$(define_swap) type=${PARTITIONING_BOOT_TYPE@Q} encrypt=${PARTITIONING_ZFS_ENCRYPTION@Q} pool_type=${PARTITIONING_ZFS_POOL_TYPE@Q}" "${PARTITIONING_DEVICES[@]@Q}" ;;
		"btrfs_centric")       define_disk_configuration_function "create_btrfs_centric_layout swap=$(define_swap) type=${PARTITIONING_BOOT_TYPE@Q} raid_type=${PARTITIONING_BTRFS_RAID_TYPE@Q} luks=${PARTITIONING_USE_LUKS@Q}" "${PARTITIONING_DEVICES[@]@Q}" ;;
		"raid0_luks")          define_disk_configuration_function "create_raid0_luks_layout swap=$(define_swap) type=${PARTITIONING_BOOT_TYPE@Q} root_fs=${PARTITIONING_ROOT_FS@Q}" "${PARTITIONING_DEVICES[@]@Q}" ;;
		"custom")
			# Show current function declaration, trim trailing whitespace
			declare -f disk_configuration \
				| sed -e 's/\s*$//'
			;;
	esac
}

ALL_PARTITIONING_SCHEMES=(
	"classic_single_disk" "Classic single disk layout (boot, swap, root)"
	"zfs_centric"         "ZFS centric (optional raid0/1 and encryption via zfs)"
	"btrfs_centric"       "Btrfs centric (optional raid0/1 via btrfs)"
	"raid0_luks"          "Raid0 (N>=2 disks) and luks for root"
	"custom"              "Custom (edit the config manually later)"
)

PARTITIONING_BOOT_TYPES=("efi" "bios")
PARTITIONING_ROOT_FS_TYPES=("ext4" "btrfs")
PARTITIONING_BTRFS_RAID_TYPES=("raid0" "raid1")
PARTITIONING_ZFS_POOL_TYPES=("standard" "custom")

function create_single_disk_layout() {
	create_classic_single_disk_layout
}

function parse_swap() {
	if [[ $1 == "false" ]]; then
		PARTITIONING_USE_SWAP=false
		PARTITIONING_SWAP=8GiB
	else
		PARTITIONING_USE_SWAP=true
		PARTITIONING_SWAP="$1"
	fi
}

function create_classic_single_disk_layout() {
	PARTITIONING_SCHEME="classic_single_disk"

	local known_arguments=('+swap' '?type' '?luks' '?root_fs')
	local extra_arguments=()
	declare -A arguments; parse_arguments "$@"

	PARTITIONING_DEVICE="${extra_arguments[0]}"
	parse_swap "${arguments[swap]}"
	PARTITIONING_BOOT_TYPE="${arguments[type]}"
	PARTITIONING_USE_LUKS="${arguments[luks]:-false}"
	PARTITIONING_ROOT_FS="${arguments[root_fs]:-ext4}"
}

function create_raid0_luks_layout() {
	PARTITIONING_SCHEME="raid0_luks"

	local known_arguments=('+swap' '?type' '?root_fs')
	local extra_arguments=()
	declare -A arguments; parse_arguments "$@"

	PARTITIONING_DEVICES=("${extra_arguments[@]}")
	parse_swap "${arguments[swap]}"
	PARTITIONING_BOOT_TYPE="${arguments[type]}"
	PARTITIONING_ROOT_FS="${arguments[root_fs]:-ext4}"
}

function create_zfs_centric_layout() {
	PARTITIONING_SCHEME="zfs_centric"

	local known_arguments=('+swap' '?type' '?pool_type' '?encrypt')
	local extra_arguments=()
	declare -A arguments; parse_arguments "$@"

	PARTITIONING_DEVICES=("${extra_arguments[@]}")
	parse_swap "${arguments[swap]}"
	PARTITIONING_BOOT_TYPE="${arguments[type]}"
	PARTITIONING_ZFS_POOL_TYPE="${arguments[pool_type]:-standard}"
	PARTITIONING_ZFS_ENCRYPTION="${arguments[encrypt]:-false}"
}

function create_btrfs_raid_layout() {
	create_btrfs_centric_layout
}

function create_btrfs_centric_layout() {
	PARTITIONING_SCHEME="btrfs_centric"

	# shellcheck disable=SC2034
	local known_arguments=('+swap' '?type' '?raid_type' '?luks')
	local extra_arguments=()
	declare -A arguments; parse_arguments "$@"

	PARTITIONING_DEVICES=("${extra_arguments[@]}")
	parse_swap "${arguments[swap]}"
	PARTITIONING_BOOT_TYPE="${arguments[type]}"
	PARTITIONING_USE_LUKS="${arguments[luks]:-false}"
	PARTITIONING_BTRFS_RAID_TYPE="${arguments[raid_type]:-raid0}"
}


################################################
# Configuration constants

get_all_keymaps
get_all_timezones
INIT_SYSTEMS=("systemd" "OpenRC")
ALL_GENTOO_ARCHS=("x86" "amd64" "arm" "arm64")
readarray -t SUPPORTED_LOCALES < "$(get_supported_locales)"
readarray -t LOCALE_A < <(locale -a)


################################################
# Load/Default configuration

function load_selected_locales() {
	local sel_locales=()
	local IFS=$'\n'
	declare -A selected_by_name
	for i in $LOCALES; do
		selected_by_name["$i"]=true
	done

	local i=0
	for item in "${SUPPORTED_LOCALES[@]}"; do
		[[ "${selected_by_name[$item]:-}" == true ]] \
			&& sel_locales+=("$i")
		((++i))
	done

	SELECTED_LOCALES="${sel_locales[*]}"
}

function process_config() {
	disk_configuration

	if [[ "$SYSTEMD" == true ]]; then
		INIT_SYSTEM="systemd"
	else
		INIT_SYSTEM="OpenRC"
	fi

	if [[ "$KEYMAP" == "$KEYMAP_INITRAMFS" ]]; then
		KEYMAP_INITRAMFS_OTHER=false
	else
		KEYMAP_INITRAMFS_OTHER=true
	fi

	load_selected_locales
	recalculate_locales
}

function load_config() {
	# First load defaults, then replace by sourcing config.
	load_default_config

	# Fallback to custom partitioning scheme if it isn't set in the actual config
	PARTITIONING_SCHEME="custom"

	# Load settings
	# shellcheck disable=SC1090
	source "$1" || die "Could not load given configuration."

	# After loading a config no unsaved changes exist.
	UNSAVED_CHANGES=false
}

function load_default_config() {
	HOSTNAME="gentoo"
	TIMEZONE="$(get_timezone)"
	KEYMAP="$(get_default_keymap)"
	KEYMAP_INITRAMFS="$KEYMAP"
	LOCALES="C.UTF-8 UTF-8"
	LOCALE="C.utf8"

	function disk_configuration() {
		create_zfs_centric_layout swap=8GiB type=efi encrypt=true pool_type=standard /dev/sdX
	}

	SYSTEMD=true

	GENTOO_MIRROR="https://mirror.eu.oneandone.net/linux/distributions/gentoo/gentoo"
	GENTOO_ARCH="amd64"

	SELECT_MIRRORS=true
	SELECT_MIRRORS_LARGE_FILE=false

	ADDITIONAL_PACKAGES=()
	INSTALL_SSHD=true
	ROOT_SSH_AUTHORIZED_KEYS=""

	# All settings are unsaved.
	UNSAVED_CHANGES=true
}

SAVE_AS_FILENAME="$RELA_CONFIG_FILE"
if [[ -e "$CONFIG_FILE" ]]; then
	load_config "$CONFIG_FILE"
else
	load_default_config
fi
process_config


################################################
# Menu helpers and constants

# $1: exit code
function clear_and_exit() {
	dialog --clear
	clear -x
	exit "$1"
}

function ellipsis() {
	local len="$1"
	shift
	local str="$*"
	if [[ "${#str}" -gt "$len" ]]; then
		echo "${str:0:$len}…"
	else
		echo "$str"
	fi
}

function on_off_toggle() {
	if [[ "${!1}" == true ]]; then
		declare -g "$1"=false
	else
		declare -g "$1"=true
	fi
}

function on_off_str() {
	if [[ "$1" == true ]]; then
		echo -n "$2"
	else
		echo -n "$3"
	fi
}

function on_off_label() {
	local prefix="${2:-}"
	on_off_str "$1" "${prefix}[*]" "${prefix}[ ]"
}

function is_on() {
	[[ "$1" == true ]]
}

function is_off() {
	[[ "$1" != true ]]
}

# if $1 is in $2..
function one_of() {
	local what="$1"
	shift
	for i in "$@"; do
		[[ "$i" == "$what" ]] \
			&& return 0
	done
	return 1
}

# $1: title
# $2: description
# $3: space separated index list of selected items (e.g. "0 1 5 6")
# $@: all items
function menu_splitlist()  {
	local title="$1"
	local description="$2"
	local selected_index_list="$3"
	shift 3

	# Build option array
	local items=()
	local item
	local i=0
	local next_selected="${selected_index_list%% *}"
	local selected_index_list="${selected_index_list#* }"
	for item in "$@"; do
		if [[ "$i" == "$next_selected" ]]; then
			items+=("$i" "$item" "on")
			next_selected="${selected_index_list%% *}"
			selected_index_list="${selected_index_list#* }"
		else
			items+=("$i" "$item" "off")
		fi
		((++i))
	done

	# Show selection dialog
	dialog \
		--title "$title" \
		--buildlist "$description\nUse ^ to focus the list of unselected items and $ to focus the list of selected items. Use <Space> to select/deselect an item and select <OK> by pressing <Enter> when finished." \
		"${BUILDLIST_SIZE[@]}" "${items[@]}"

	local diag_exit=$?
	if [[ $diag_exit == 0 ]]; then
		# <OK>
		return 0
	elif [[ $diag_exit == 1 ]]; then
		# <Cancel>
		return 1
	else
		# <ESC><ESC>
		return 1
	fi
}

# $1: title
# $2: description
# $3: default item
# $@: [tag label]...
function menu_radiolist_labeled() {
	local title="$1"
	local description="$2"
	local default_item="$3"
	shift 3

	# Build option array
	local items=()
	local tag
	local label
	while [[ "$#" -gt 0 ]]; do
		tag="$1"
		label="$2"
		shift 2

		if [[ $tag == "$default_item" ]]; then
			items+=("$tag" "$label" "on")
		else
			items+=("$tag" "$label" "off")
		fi
	done

	# Show selection dialog
	dialog \
		--no-tags \
		--title "$title" \
		--help-button \
		--help-label "Select" \
		--help-status \
		--ok-label "OK" \
		--default-item "$default_item" \
		--default-button help \
		--radiolist "$description\nUse <Select> to select the option under the cursor, or <OK> to use the option which is selected with an asterisk." \
		"${RADIOLIST_SIZE[@]}" "${items[@]}"

	local diag_exit=$?
	if [[ $diag_exit == 0 ]]; then
		# <OK>
		return 0
	elif [[ $diag_exit == 1 ]]; then
		# <Cancel>
		return 1
	elif [[ $diag_exit == 2 ]]; then
		# <Select>
		local sel="${dialog_out#HELP }"
		local sel_cur="${sel% *}"
		#local sel_radio="${sel#* }"
		dialog_out="$sel_cur"
		return 0
	else
		# <ESC><ESC>
		return 1
	fi
}

# $1: title
# $2: description
# $3: default item
# $@: items
function menu_radiolist()  {
	local title="$1"
	local description="$2"
	local default_item="$3"
	shift 3

	# Build option array
	local items=()
	local item
	for item in "$@"; do
		if [[ $item == "$default_item" ]]; then
			items+=("$item" "on")
		else
			items+=("$item" "off")
		fi
	done

	# Show selection dialog
	dialog \
		--no-items \
		--title "$title" \
		--help-button \
		--help-label "Select" \
		--help-status \
		--ok-label "OK" \
		--default-item "$default_item" \
		--default-button help \
		--radiolist "$description\nUse <Select> to select the option under the cursor, or <OK> to use the option which is selected with an asterisk." \
		"${RADIOLIST_SIZE[@]}" "${items[@]}"

	local diag_exit="$?"
	if [[ $diag_exit == 0 ]]; then
		# <OK>
		return 0
	elif [[ $diag_exit == 1 ]]; then
		# <Cancel>
		return 1
	elif [[ $diag_exit == 2 ]]; then
		# <Select>
		local sel="${dialog_out#HELP }"
		local sel_cur="${sel% *}"
		#local sel_radio="${sel#* }"
		dialog_out="$sel_cur"
		return 0
	else
		# <ESC><ESC>
		return 1
	fi
}

function msgbox_help() {
	dialog --msgbox "$1" "${HELP_POPUP_SIZE[@]}"
}

function menu_exit() {
	if [[ $UNSAVED_CHANGES == "true" ]]; then
		dialog \
			--help-button --help-label "Back" \
			--yes-label "Save" --no-label "Discard" \
			--yesno "Do you want to save your configuration?\n(Press <ESC><ESC>, or choose <Back> to continue gentoo configuration)." \
			"${CONFIRM_SIZE[@]}"

		local diag_exit="$?"
		if [[ $diag_exit == 0 ]]; then
			# <Save>
			save "$CONFIG_FILE"
			clear_and_exit 0
		elif [[ $diag_exit == 1 ]]; then
			# <Discard>
			clear_and_exit 0
		else
			# Back to menu (<ESC><ESC>, <Back>)
			true
		fi
	else
		# Nothing was changed. Exit immediately.
		clear_and_exit 0
	fi
}

function menu_save_as() {
	dialog \
		--ok-label "Save" \
		--inputbox "Enter a filename to which this configuration should be saved.\n(Press <ESC><ESC>, or choose <Cancel> to abort)." \
		"${INPUTBOX_SIZE[@]}" "$SAVE_AS_FILENAME"

	local diag_exit="$?"
	if [[ $diag_exit == 0 ]]; then
		# <Save>
		SAVE_AS_FILENAME="$dialog_out"
		save "$SAVE_AS_FILENAME"
		UNSAVED_CHANGES=false
	else
		# Back to menu (<ESC><ESC>, <Cancel>)
		true
	fi
}

function menu() {
	local item
	local item_tag
	local tag_item_list=()
	declare -A reverse_lookup

	# Create menu list
	for item in "${MENU_ITEMS[@]}"; do
		# Only if item is visible
		"${item}_show" || continue

		item_tag="$("${item}_tag")"
		tag_item_list+=("$item_tag" "$("${item}_label")")
		reverse_lookup["$item_tag"]="$item"
	done

	dialog --colors \
		--title "Gentoo configuration ($RELA_CONFIG_FILE)" \
		--extra-button --extra-label "Exit" \
		--help-button \
		--default-item "$SELECTED_MENU_ITEM" \
		--ok-label "Select" --cancel-label "Save" \
		--menu "This is the gentoo configuration menu. Read and adjust all options below carefully. Save your desired configuration and run ./install afterwards. Use <Help> if you want further information on any option." \
		"${MENU_SIZE[@]}" "${tag_item_list[@]}"

	local diag_exit="$?"
	if [[ $diag_exit == 0 ]]; then
		# <Select>
		SELECTED_MENU_ITEM="$dialog_out"
		[[ -z "$SELECTED_MENU_ITEM" ]] \
			|| "${reverse_lookup[$SELECTED_MENU_ITEM]}_menu"
	elif [[ $diag_exit == 1 ]]; then
		# <Save>
		SELECTED_MENU_ITEM="$dialog_out"
		menu_save_as
	elif [[ $diag_exit == 2 ]]; then
		# <Help>
		SELECTED_MENU_ITEM="${dialog_out#HELP }"
		msgbox_help "$("${reverse_lookup[$SELECTED_MENU_ITEM]}_help")"
	else
		# Exit (<ESC><ESC>, <Exit>)
		SELECTED_MENU_ITEM="${dialog_out:-$SELECTED_MENU_ITEM}"
		menu_exit
		true
	fi
}

SELECTED_MENU_ITEM=""
MENU_SIZE=("20" "76" "12")
INPUTBOX_SIZE=("11" "76")
EDITTEXT_SIZE=("16" "76")
RADIOLIST_SIZE=("20" "76" "8")
BUILDLIST_SIZE=("20" "76" "8")
HELP_POPUP_SIZE=("8" "66")
CONFIRM_SIZE=("8" "66")


################################################
# Menu definition

MENU_ITEMS=(
	"PARTITIONING_SCHEME"
	"PARTITIONING_BOOT_TYPE"
	"PARTITIONING_USE_SWAP"
	"PARTITIONING_SWAP"
	"PARTITIONING_ROOT_FS"
	"PARTITIONING_USE_LUKS"
	"PARTITIONING_ZFS_POOL_TYPE"
	"PARTITIONING_ZFS_ENCRYPTION"
	"PARTITIONING_BTRFS_RAID_TYPE"
	"PARTITIONING_DEVICE"
	"PARTITIONING_DEVICES"
	"--------"
	"HOSTNAME"
	"TIMEZONE"
	"KEYMAP"
	"KEYMAP_INITRAMFS_OTHER"
	"KEYMAP_INITRAMFS"
	"LOCALES"
	"LOCALE"
	"--------"
	"INIT_SYSTEM"
	"GENTOO_MIRROR"
	"GENTOO_ARCH"
	"SELECT_MIRRORS"
	"SELECT_MIRRORS_LARGE_FILE"
	"--------"
	"INSTALL_SSHD"
	"ROOT_SSH_AUTHORIZED_KEYS"
	"ADDITIONAL_PACKAGES"
)

function --------_tag()   { echo "────────────────────────────"; }
function --------_label() { echo "────────────────────────────"; }
function --------_show()  { return 0; }
function --------_help()  { echo "Congratulations, you found a separator."; }
function --------_menu()  { true; }

function PARTITIONING_SCHEME_tag()   { echo "Partitioning scheme"; }
function PARTITIONING_SCHEME_label() { echo "($PARTITIONING_SCHEME)"; }
function PARTITIONING_SCHEME_show()  { return 0; }
function PARTITIONING_SCHEME_help()  { echo "Select the desired partitioning scheme."; }
function PARTITIONING_SCHEME_menu()  {
	if menu_radiolist_labeled \
		"Select partitioning scheme" \
		"Select which partitioning scheme you want to follow. Have a look at the help text for this option (available in the menu) for more details.\n\nAll options support EFI/BIOS, swap and some form of encryption (luks/zfs).\n" \
		"$PARTITIONING_SCHEME" \
		"${ALL_PARTITIONING_SCHEMES[@]}"
	then
		# Set disk scheme
		case "$dialog_out" in
			"classic_single_disk") create_classic_single_disk_layout swap=8GiB type=efi luks=false root_fs=ext4 /dev/sdX ;;
			"zfs_centric")         create_zfs_centric_layout swap=8GiB type=efi encrypt=true pool_type=standard /dev/sdX ;;
			"btrfs_centric")       create_btrfs_centric_layout swap=8GiB type=efi raid_type=raid0 luks=false /dev/sdX ;;
			"raid0_luks")          create_raid0_luks_layout swap=8GiB type=efi root_fs=ext4 /dev/sdX /dev/sdY ;;
			"custom")              PARTITIONING_SCHEME="$dialog_out" ;;
		esac
		UNSAVED_CHANGES=true
	else
		# Return to menu
		true
	fi
}

function PARTITIONING_BOOT_TYPE_tag()   { echo " ├ Boot type"; }
function PARTITIONING_BOOT_TYPE_label() { echo " ├ ($PARTITIONING_BOOT_TYPE)"; }
function PARTITIONING_BOOT_TYPE_show()  { [[ $PARTITIONING_SCHEME != "custom" ]]; }
function PARTITIONING_BOOT_TYPE_help()  { echo "Select whether to use EFI or BIOS boot."; }
function PARTITIONING_BOOT_TYPE_menu()  {
	if menu_radiolist \
		"Select boot type" \
		"Select whether your want to use EFI or BIOS boot." \
		"$PARTITIONING_BOOT_TYPE" \
		"${PARTITIONING_BOOT_TYPES[@]}"
	then
		# Set timezone
		PARTITIONING_BOOT_TYPE="$dialog_out"
		UNSAVED_CHANGES=true
	else
		# Return to menu
		true
	fi
}

function PARTITIONING_USE_SWAP_tag()   { echo " ├ Use swap"; }
function PARTITIONING_USE_SWAP_label() { on_off_label "$PARTITIONING_USE_SWAP" " ├ "; }
function PARTITIONING_USE_SWAP_show()  { [[ $PARTITIONING_SCHEME != "custom" ]]; }
function PARTITIONING_USE_SWAP_help()  { echo "Select whether or not to create a swap partition."; }
function PARTITIONING_USE_SWAP_menu()  {
	on_off_toggle "PARTITIONING_USE_SWAP"
	UNSAVED_CHANGES=true
}

function PARTITIONING_SWAP_tag()   { echo " │  └ Swap amount"; }
function PARTITIONING_SWAP_label() { echo " │  └ ($PARTITIONING_SWAP)"; }
function PARTITIONING_SWAP_show()  { [[ $PARTITIONING_SCHEME != "custom" ]] && is_on "$PARTITIONING_USE_SWAP"; }
function PARTITIONING_SWAP_help()  { echo "Select the amount of swap to use."; }
function PARTITIONING_SWAP_menu()  {
	dialog \
		--title "Select swap amount" \
		--inputbox "Enter the amount of swap for the new system. Use the correct suffix (e.g. 16GiB, 1000MB)." \
		"${INPUTBOX_SIZE[@]}" "$PARTITIONING_SWAP"
	PARTITIONING_SWAP="$dialog_out"
	UNSAVED_CHANGES=true
}

function PARTITIONING_ROOT_FS_tag()   { echo " ├ Root filesystem"; }
function PARTITIONING_ROOT_FS_label() { echo " ├ ($PARTITIONING_ROOT_FS)"; }
function PARTITIONING_ROOT_FS_show()  { [[ $PARTITIONING_SCHEME != "custom" ]] && one_of "$PARTITIONING_SCHEME" "classic_single_disk" "raid0_luks"; }
function PARTITIONING_ROOT_FS_help()  { echo "Select the amount of swap to use."; }
function PARTITIONING_ROOT_FS_menu()  {
	if menu_radiolist \
		"Select root fstype" \
		"Select which filesystem to use on the root partition." \
		"$PARTITIONING_ROOT_FS" \
		"${PARTITIONING_ROOT_FS_TYPES[@]}"
	then
		# Set timezone
		PARTITIONING_ROOT_FS="$dialog_out"
		UNSAVED_CHANGES=true
	else
		# Return to menu
		true
	fi
}

function PARTITIONING_USE_LUKS_tag()   { echo " ├ Use LUKS"; }
function PARTITIONING_USE_LUKS_label() { on_off_label "$PARTITIONING_USE_LUKS" " ├ "; }
function PARTITIONING_USE_LUKS_show()  { [[ $PARTITIONING_SCHEME != "custom" ]] && one_of "$PARTITIONING_SCHEME" "classic_single_disk" "btrfs_centric"; }
function PARTITIONING_USE_LUKS_help()  { echo "Determines if LUKS will be used to encrypt your root partition."; }
function PARTITIONING_USE_LUKS_menu()  {
	on_off_toggle "PARTITIONING_USE_LUKS"
	UNSAVED_CHANGES=true
}

function PARTITIONING_ZFS_ENCRYPTION_tag()   { echo " ├ ZFS Encryption"; }
function PARTITIONING_ZFS_ENCRYPTION_label() { on_off_label "$PARTITIONING_ZFS_ENCRYPTION" " ├ "; }
function PARTITIONING_ZFS_ENCRYPTION_show()  { [[ $PARTITIONING_SCHEME != "custom" ]] && one_of "$PARTITIONING_SCHEME" "zfs_centric" && one_of "$PARTITIONING_ZFS_POOL_TYPE" "standard"; }
function PARTITIONING_ZFS_ENCRYPTION_help()  { echo "Determines if ZFS encryption will be used to encrypt your root partition."; }
function PARTITIONING_ZFS_ENCRYPTION_menu()  {
	on_off_toggle "PARTITIONING_ZFS_ENCRYPTION"
	UNSAVED_CHANGES=true
}

function PARTITIONING_ZFS_POOL_TYPE_tag()   { echo " ├ Pool type"; }
function PARTITIONING_ZFS_POOL_TYPE_label() { echo " ├ ($PARTITIONING_ZFS_POOL_TYPE)"; }
function PARTITIONING_ZFS_POOL_TYPE_show()  { [[ $PARTITIONING_SCHEME != "custom" ]] && one_of "$PARTITIONING_SCHEME" "zfs_centric"; }
function PARTITIONING_ZFS_POOL_TYPE_help()  { echo "Determines how the zfs pool will be initialized. Select 'standard' for a default pool setup that puts all given devices in one pool with ZSTD compression. Selecting 'custom' will require you to write your own pool creation function in the output config."; }
function PARTITIONING_ZFS_POOL_TYPE_menu()  {
	if menu_radiolist \
		"Select ZFS pool type" \
		"Select 'standard' for a default pool setup that puts all given devices in one pool with ZSTD compression. Selecting 'custom' will require you to write your own pool creation function in the output config." \
		"$PARTITIONING_ZFS_POOL_TYPE" \
		"${PARTITIONING_ZFS_POOL_TYPES[@]}"
	then
		# Set timezone
		PARTITIONING_ZFS_POOL_TYPE="$dialog_out"
		UNSAVED_CHANGES=true
	else
		# Return to menu
		true
	fi
}

function PARTITIONING_BTRFS_RAID_TYPE_tag()   { echo " ├ Btrfs raid type"; }
function PARTITIONING_BTRFS_RAID_TYPE_label() { echo " ├ ($PARTITIONING_BTRFS_RAID_TYPE)"; }
function PARTITIONING_BTRFS_RAID_TYPE_show()  { [[ $PARTITIONING_SCHEME != "custom" ]] && one_of "$PARTITIONING_SCHEME" "btrfs_centric"; }
function PARTITIONING_BTRFS_RAID_TYPE_help()  { echo "Determines the type of the btrfs pool."; }
function PARTITIONING_BTRFS_RAID_TYPE_menu()  {
	if menu_radiolist \
		"Select raid type" \
		"Select which raid type to use for the btrfs pool." \
		"$PARTITIONING_BTRFS_RAID_TYPE" \
		"${PARTITIONING_BTRFS_RAID_TYPES[@]}"
	then
		# Set timezone
		PARTITIONING_BTRFS_RAID_TYPE="$dialog_out"
		UNSAVED_CHANGES=true
	else
		# Return to menu
		true
	fi
}

function PARTITIONING_DEVICE_tag()   { echo " └ Device"; }
function PARTITIONING_DEVICE_label() {
	if [[ -e "$PARTITIONING_DEVICE" ]]; then
		echo " └ ($PARTITIONING_DEVICE)"
	else
		echo " └ (\Z1$PARTITIONING_DEVICE\Zn)"
	fi
}
function PARTITIONING_DEVICE_show()  { [[ $PARTITIONING_SCHEME != "custom" ]] && one_of "$PARTITIONING_SCHEME" "classic_single_disk"; }
function PARTITIONING_DEVICE_help()  { echo "The block device to which the layout will be applied."; }
function PARTITIONING_DEVICE_menu()  {
	dialog \
		--title "Select device" \
		--inputbox "Enter the path of the device which you want to partition. (e.g. /dev/sda)." \
		"${INPUTBOX_SIZE[@]}" "$PARTITIONING_DEVICE"
	PARTITIONING_DEVICE="$dialog_out"
	UNSAVED_CHANGES=true
}

function PARTITIONING_DEVICES_tag()   { echo " └ Devices"; }
function PARTITIONING_DEVICES_label() {
	local invalid=0
	for dev in "${PARTITIONING_DEVICES[@]}"; do
		[[ -e "$dev" ]] \
			|| ((++invalid))
	done

	if [[ "$invalid" -gt 0 ]]; then
		echo " └ (${#PARTITIONING_DEVICES[@]} devices, \Z1$invalid invalid\Zn)"
	elif [[ "${#PARTITIONING_DEVICES[@]}" -eq 1 && "$PARTITIONING_SCHEME" == "raid0_luks" ]]; then
		echo " └ (${#PARTITIONING_DEVICES[@]} devices, \Z1need at least 2\Zn)"
	elif [[ "${#PARTITIONING_DEVICES[@]}" -eq 0 ]]; then
		echo " └ (${#PARTITIONING_DEVICES[@]} devices, \Z1need at least 1\Zn)"
	else
		echo " └ (${#PARTITIONING_DEVICES[@]} devices)"
	fi
}
function PARTITIONING_DEVICES_show()  { [[ $PARTITIONING_SCHEME != "custom" ]] && one_of "$PARTITIONING_SCHEME" "raid0_luks" "zfs_centric" "btrfs_centric"; }
function PARTITIONING_DEVICES_help()  { echo "The block devices to which the layout will be applied."; }
function PARTITIONING_DEVICES_menu()  {
	local invalid=()
	for dev in "${PARTITIONING_DEVICES[@]}"; do
		[[ -e "$dev" ]] \
			|| invalid+=("$dev")
	done

	local invalid_line=""
	if [[ "${#invalid[@]}" -gt 0 ]]; then
		invalid_line="\n\nInvalid devices: \Z1${invalid[*]}\Zn"
	fi

	dialog \
		--title "Select devices" \
		--inputbox "Enter the path of all devices which you want to partition, separated by space. (e.g. /dev/sda /dev/sdb).$invalid_line" \
		"${INPUTBOX_SIZE[@]}" "${PARTITIONING_DEVICES[*]}"
	read -ra PARTITIONING_DEVICES <<< "$dialog_out"
	UNSAVED_CHANGES=true
}

function HOSTNAME_tag()   { echo "Hostname"; }
function HOSTNAME_label() { echo "($HOSTNAME)"; }
function HOSTNAME_show()  { return 0; }
function HOSTNAME_help()  { echo "Enter the desired system hostname here. Be aware that when creating mdadm raid arrays, this value will be recorded in metadata block. If you change it later, you should also update the metadata."; }
function HOSTNAME_menu()  {
	dialog \
		--title "Select hostname" \
		--inputbox "Enter the hostname for your new system." \
		"${INPUTBOX_SIZE[@]}" "$HOSTNAME"
	HOSTNAME="$dialog_out"
	UNSAVED_CHANGES=true
}

function TIMEZONE_tag()   { echo "Timezone"; }
function TIMEZONE_label() { echo "($TIMEZONE)"; }
function TIMEZONE_show()  { return 0; }
function TIMEZONE_help()  { echo "The timezone for the new system."; }
function TIMEZONE_menu()  {
	if menu_radiolist \
		"Select timezone" \
		"Select which timezone to use." \
		"$TIMEZONE" \
		"${ALL_TIMEZONES[@]}"
	then
		# Set timezone
		TIMEZONE="$dialog_out"
		UNSAVED_CHANGES=true
	else
		# Return to menu
		true
	fi
}

function KEYMAP_tag()   { echo "Keymap"; }
function KEYMAP_label() { echo "($KEYMAP)"; }
function KEYMAP_show()  { return 0; }
function KEYMAP_help()  { echo "The default vconsole keymap for the system."; }
function KEYMAP_menu()  {
	if menu_radiolist \
		"Select initramfs keymap" \
		"Select which keymap to use in the vconsole." \
		"$KEYMAP" \
		"${ALL_KEYMAPS[@]}"
	then
		# Set keymap
		KEYMAP="$dialog_out"
		UNSAVED_CHANGES=true
	else
		# Return to menu
		true
	fi
}

function KEYMAP_INITRAMFS_OTHER_tag()   { echo "Different initramfs keymap"; }
function KEYMAP_INITRAMFS_OTHER_label() { on_off_label "$KEYMAP_INITRAMFS_OTHER"; }
function KEYMAP_INITRAMFS_OTHER_show()  { return 0; }
function KEYMAP_INITRAMFS_OTHER_help()  { echo "Whether another keymap should be used for the initramfs. If enabled, you will be able to choose a separate keymap below."; }
function KEYMAP_INITRAMFS_OTHER_menu()  {
	on_off_toggle "KEYMAP_INITRAMFS_OTHER"
	UNSAVED_CHANGES=true
	[[ -z $KEYMAP_INITRAMFS ]] \
		&& KEYMAP_INITRAMFS="$KEYMAP"
}

function KEYMAP_INITRAMFS_tag()   { echo " └ Keymap (initramfs)"; }
function KEYMAP_INITRAMFS_label() { echo " └ ($KEYMAP_INITRAMFS)"; }
function KEYMAP_INITRAMFS_show()  { is_on "$KEYMAP_INITRAMFS_OTHER"; }
function KEYMAP_INITRAMFS_help()  { echo "The default vconsole keymap for the initrams. This is important if need to unlock an encrypted partition when booting."; }
function KEYMAP_INITRAMFS_menu()  {
	if menu_radiolist \
		"Select initramfs keymap" \
		"Select which keymap to use in the initramfs vconsole." \
		"$KEYMAP_INITRAMFS" \
		"${ALL_KEYMAPS[@]}"
	then
		# Set keymap
		KEYMAP_INITRAMFS="$dialog_out"
		UNSAVED_CHANGES=true
	else
		# Return to menu
		true
	fi
}

function LOCALES_tag()   { echo "Locales"; }
function LOCALES_label() { echo "$N_LOCALES selected"; }
function LOCALES_show()  { return 0; }
function LOCALES_help()  { echo "The locales to generate for the new system. Be careful that the syntax for locales is a different from the resulting name of the genereated locales of locale-gen. For example the locale 'en_US.utf8' is enabled via 'en_US.UTF-8 UTF-8')."; }
function LOCALES_menu()  {
	if menu_splitlist "Select locales" "Select which locales to generate." "$SELECTED_LOCALES" "${SUPPORTED_LOCALES[@]}"; then
		# Set locales
		SELECTED_LOCALES="$dialog_out"
		recalculate_locales
		UNSAVED_CHANGES=true
	else
		# Return to menu
		true
	fi
}

function LOCALE_tag()   { echo "Default locale"; }
function LOCALE_label() { echo "($LOCALE)"; }
function LOCALE_show()  { return 0; }
function LOCALE_help()  { echo "The locale to use for the new system. See \`locale -a\` for available options, and be sure to generate the locale by adding it to the list of locales above."; }
function LOCALE_menu()  {
	if menu_radiolist \
		"Select default locale" \
		"Select which locale to use as the default. Remember to also add the desired locale to the list of locales above." \
		"$LOCALE" \
		"${LOCALE_A[@]}"
	then
		# Set locale
		LOCALE="$dialog_out"
		UNSAVED_CHANGES=true
	else
		# Return to menu
		true
	fi
}

function INIT_SYSTEM_tag()   { echo "Init system"; }
function INIT_SYSTEM_label() { echo "($INIT_SYSTEM)"; }
function INIT_SYSTEM_show()  { return 0; }
function INIT_SYSTEM_help()  { echo ""; }
function INIT_SYSTEM_menu()  {
	if menu_radiolist \
		"Select init system" \
		"Select the init system you want to use." \
		"$INIT_SYSTEM" \
		"${INIT_SYSTEMS[@]}"
	then
		# Set init system
		INIT_SYSTEM="$dialog_out"
		UNSAVED_CHANGES=true
	else
		# Return to menu
		true
	fi
}

function GENTOO_MIRROR_tag()   { echo "Gentoo mirror"; }
function GENTOO_MIRROR_label() { echo "($(ellipsis 20 "$GENTOO_MIRROR"))"; }
function GENTOO_MIRROR_show()  { return 0; }
function GENTOO_MIRROR_help()  { echo "Enter the initial gentoo mirror that should be used for the installation process (until mirrorselect is run)."; }
function GENTOO_MIRROR_menu()  {
	dialog \
		--title "Select gentoo mirror" \
		--inputbox "Enter the initial gentoo mirror that should be used for the installation process (until mirrorselect is run)." \
		"${INPUTBOX_SIZE[@]}" "$GENTOO_MIRROR"
	UNSAVED_CHANGES=true
}

function GENTOO_ARCH_tag()   { echo "Gentoo arch"; }
function GENTOO_ARCH_label() { echo "($GENTOO_ARCH)"; }
function GENTOO_ARCH_show()  { return 0; }
function GENTOO_ARCH_help()  { echo "Select gentoo's architecture tag for the new system."; }
function GENTOO_ARCH_menu()  {
	if menu_radiolist \
		"Select architecture" \
		"Select the architecture for the new system." \
		"$GENTOO_ARCH" \
		"${ALL_GENTOO_ARCHS[@]}"
	then
		# Set arch
		GENTOO_ARCH="$dialog_out"
		UNSAVED_CHANGES=true
	else
		# Return to menu
		true
	fi
}

function SELECT_MIRRORS_tag()   { echo "Run mirrorselect"; }
function SELECT_MIRRORS_label() { on_off_label "$SELECT_MIRRORS"; }
function SELECT_MIRRORS_show()  { return 0; }
function SELECT_MIRRORS_help()  { echo "Determines if mirrorselect will be used to determine the best gentoo mirror for the new system."; }
function SELECT_MIRRORS_menu()  {
	on_off_toggle "SELECT_MIRRORS"
	UNSAVED_CHANGES=true
}

function SELECT_MIRRORS_LARGE_FILE_tag()   { echo " └ Use large files"; }
function SELECT_MIRRORS_LARGE_FILE_label() { on_off_label "$SELECT_MIRRORS_LARGE_FILE" " └ "; }
function SELECT_MIRRORS_LARGE_FILE_show()  { is_on "$SELECT_MIRRORS"; }
function SELECT_MIRRORS_LARGE_FILE_help()  { echo "Determines if mirrorselect uses large files (~10MB) to test mirrors."; }
function SELECT_MIRRORS_LARGE_FILE_menu()  {
	on_off_toggle "SELECT_MIRRORS_LARGE_FILE"
	UNSAVED_CHANGES=true
}

function INSTALL_SSHD_tag()   { echo "Install sshd"; }
function INSTALL_SSHD_label() { on_off_label "$INSTALL_SSHD"; }
function INSTALL_SSHD_show()  { return 0; }
function INSTALL_SSHD_help()  { echo "Install and enable sshd on the new system. A reasonably secure sshd configuration will be provided. It will by default only allow ed25519 keys, restrict key exchange algorithms to a reasonable subset, disable any password based authentication, and only allow root to login."; }
function INSTALL_SSHD_menu()  {
	on_off_toggle "INSTALL_SSHD"
	UNSAVED_CHANGES=true
}

function ROOT_SSH_AUTHORIZED_KEYS_tag()   { echo "Authorized keys (root)"; }
function ROOT_SSH_AUTHORIZED_KEYS_label() { echo "$(sed '/^\s*#/d;/^\s*$/d' <<< "$ROOT_SSH_AUTHORIZED_KEYS" | wc -l) keys"; }
function ROOT_SSH_AUTHORIZED_KEYS_show()  { return 0; }
function ROOT_SSH_AUTHORIZED_KEYS_help()  { echo "The authorized keys for ssh root login, one per line."; }
function ROOT_SSH_AUTHORIZED_KEYS_menu()  {
	# Prepare file to edit in dialog,
	# unfortunately <() won't work (probably EOF is encountered before content is available).
	local tmpfile
	tmpfile="$(mktemp)" || die "Could not create temporary file."
	cat > "$tmpfile" <<EOF
# Enter all authorized keys for ssh root login.
# Use <Tab> to navigate between the inputbox, <OK> and <Cancel>.
#
# All comments will be removed from the final file.
# If you are on a vconsole and have no means of entering this now,
# simply edit the final configuration later with a text editor.

#ssh-ed25519 ......
$ROOT_SSH_AUTHORIZED_KEYS
EOF

	dialog \
		--title "Enter authorized keys" \
		--editbox "$tmpfile" "${EDITTEXT_SIZE[@]}"
	ROOT_SSH_AUTHORIZED_KEYS="$(sed '/^\s*#/d;/^\s*$/d' <<< "$dialog_out")"
	UNSAVED_CHANGES=true
}

function ADDITIONAL_PACKAGES_tag()   { echo "Additional packages"; }
function ADDITIONAL_PACKAGES_label() { echo "${#ADDITIONAL_PACKAGES[@]} packages"; }
function ADDITIONAL_PACKAGES_show()  { return 0; }
function ADDITIONAL_PACKAGES_help()  { echo "Enter additional packages that should be installed. It is recommended to keep this to a minimum, because of the quite \"interactive\" nature of gentoo package management ;)"; }
function ADDITIONAL_PACKAGES_menu()  {
	dialog \
		--title "Additional packages" \
		--inputbox "Enter additional packages (portage package ATOMs) to install. Delimited by space." \
		"${INPUTBOX_SIZE[@]}" "${ADDITIONAL_PACKAGES[*]}"
	# shellcheck disable=SC2206
	ADDITIONAL_PACKAGES=($dialog_out)
	UNSAVED_CHANGES=true
}


################################################
# Menu functions

# $1: filename
function save() {
	if [[ "$KEYMAP_INITRAMFS_OTHER" == "false" ]]; then
		KEYMAP_INITRAMFS="$KEYMAP"
	fi

	cat > "$1" <<EOF
# vim: set ft=sh ts=4 sw=4 sts=-1 noet:
# This file will be interpreted by /bin/bash.


################################################
# Disk configuration

$(define_disk_layout)


################################################
# System configuration

HOSTNAME=${HOSTNAME@Q}
TIMEZONE=${TIMEZONE@Q}
KEYMAP=${KEYMAP@Q}
KEYMAP_INITRAMFS=${KEYMAP_INITRAMFS@Q}

LOCALES=${LOCALES@Q}
LOCALE=${LOCALE@Q}


################################################
# Gentoo configuration

GENTOO_MIRROR=${GENTOO_MIRROR@Q}
GENTOO_ARCH=${GENTOO_ARCH@Q}
STAGE3_BASENAME="stage3-\$GENTOO_ARCH$([[ $SYSTEMD == true ]] && echo -n "-systemd")"
SELECT_MIRRORS=${SELECT_MIRRORS@Q}
SELECT_MIRRORS_LARGE_FILE=${SELECT_MIRRORS_LARGE_FILE@Q}
SYSTEMD=${SYSTEMD@Q}


################################################
# Additional (optional) configuration

ADDITIONAL_PACKAGES=(${ADDITIONAL_PACKAGES[@]@Q})
INSTALL_SSHD=${INSTALL_SSHD@Q}
ROOT_SSH_AUTHORIZED_KEYS=${ROOT_SSH_AUTHORIZED_KEYS@Q}


################################################
# Prove that you have read the config

I_HAVE_READ_AND_EDITED_THE_CONFIG_PROPERLY=true
EOF
}

trap 'clear_and_exit 130' SIGINT

# Begin menu loop. Exit will be called to end this loop where it is appropriate.
while true; do
	menu
done