#cwd := $(notdir $(patsubst %/,%,$(dir $(abspath $(lastword $(MAKEFILE_LIST))))))
MERMET_MACHINE     ?= apu2e4
MERMET_HOSTING     ?= lab
mermet_disk        := $(shell sed -ne 's/^device: \(.*\)/\1/p' machine/$(MERMET_MACHINE)/sfdisk.txt)
mermet_cipher      :=
#mermet_cipher      := aes-128-gcm
mermet_autotrim    :=
mermet_reservation := 40G
#mermet_channel     := $$(nix-env -p /nix/var/nix/profiles/per-user/$$USER/channels -q nixpkgs --no-name --out-path)

echo:
	echo $(MAKEFILES)

mermet-wipeout: mermet-umount
	sudo zpool labelclear -f $(mermet_disk)-part3 || true
	sudo zpool labelclear -f $(mermet_disk)-part5 || true
	sudo $$(which sgdisk) --zap-all $(mermet_disk)

mermet-partition:
	sudo modprobe zfs
	sudo $$(which sfdisk) $(mermet_disk) <machine/$(MERMET_MACHINE)/sfdisk.txt
	sudo $$(which sgdisk) --randomize-guids $(mermet_disk)
	sudo partprobe

mermet-format:
	# DOC: https://github.com/zfsonlinux/zfs/wiki/Debian-Buster-Root-on-ZFS
	sudo mkdir -p /mnt/mermet
	blkid -t TYPE=ext2 $(mermet_disk)-part3; test $$? != 2 || \
	mkfs.ext2 $(mermet_disk)-part3
	# bpool
	## NOTE: enable only ZFS features supported by GRUB
	#sudo zpool list bpool 2>/dev/null || \
	#sudo zpool create -o ashift=12 -d \
	# -o feature@allocation_classes=enabled \
	# -o feature@async_destroy=enabled \
	# -o feature@bookmarks=enabled \
	# -o feature@embedded_data=enabled \
	# -o feature@empty_bpobj=enabled \
	# -o feature@enabled_txg=enabled \
	# -o feature@extensible_dataset=enabled \
	# -o feature@filesystem_limits=enabled \
	# -o feature@hole_birth=enabled \
	# -o feature@large_blocks=enabled \
	# -o feature@lz4_compress=enabled \
	# -o feature@project_quota=enabled \
	# -o feature@resilver_defer=enabled \
	# -o feature@spacemap_histogram=enabled \
	# -o feature@spacemap_v2=enabled \
	# -o feature@userobj_accounting=enabled \
	# -o feature@zpool_checkpoint=enabled \
	# -o feature@multi_vdev_crash_dump=disabled \
	# -o feature@large_dnode=disabled \
	# -o feature@sha512=disabled \
	# -o feature@skein=disabled \
	# -o feature@edonr=disabled \
	# -O normalization=formD \
	# -R /mnt/mermet bpool $(mermet_disk)-part3
	#sudo zfs set \
	# acltype=posixacl \
	# canmount=off \
	# compression=lz4 \
	# devices=off \
	# relatime=on \
	# xattr=sa \
	# mountpoint=/ \
	# bpool
	
	# swap
	# FIXME: configure with a volatile key in configuration.nix
	#blkid -t TYPE=crypto_LUKS $(mermet_disk)-part4; test $$? != 2 || \
	#sudo cryptsetup luksFormat --cipher aes-xts-plain64 --key-size 256 --hash sha256 $(mermet_disk)-part4
	#sudo cryptsetup luksOpen $(mermet_disk)-part4 mermet-swap
	#blkid -t TYPE=swap /dev/mapper/mermet--swap; test $$? != 2 || \
	#sudo mkswap --check --label swap
	#sudo cryptsetup luksClose $(mermet_disk)-part4 mermet-swap
	# rpool
	sudo zpool list rpool 2>/dev/null || \
	sudo zpool create -o ashift=12 \
	 $(if $(mermet_cipher),-O encryption=$(mermet_cipher) \
	 -O keyformat=passphrase \
	 -O keylocation=prompt) \
	 -O normalization=formD \
	 -R /mnt/mermet rpool $(mermet_disk)-part5
	sudo zfs set \
	 acltype=posixacl \
	 atime=off \
	 $(if $(mermet_autotrim),autotrim=on) \
	 canmount=off \
	 compression=lz4 \
	 dnodesize=auto \
	 relatime=on \
	 $(if $(mermet_reservation),reservation=$(mermet_reservation)) \
	 xattr=sa \
	 mountpoint=/ \
	 rpool
	# /
	# NOTE: mountpoint=legacy is required to let NixOS mount the ZFS filesystems.
	sudo zfs list rpool/root 2>/dev/null || \
	sudo zfs create \
	 -o canmount=on \
	 -o mountpoint=legacy \
	 rpool/root
	# /boot
	#sudo zfs list bpool/boot 2>/dev/null || \
	#sudo zfs create \
	# -o canmount=on \
	# -o mountpoint=legacy \
	# bpool/boot
	# /boot/efi
	sudo blkid $(mermet_disk)-part2 -t TYPE=vfat || \
	sudo mkfs.vfat -F 32 -s 1 -n EFI $(mermet_disk)-part2
	# /*
	for p in \
	 home \
	 nix \
	 nix/var \
	 var \
	 var/cache \
	 var/log \
	 var/mail \
	 var/tmp \
	 var/www \
	 ; do \
		sudo zfs list rpool/"$$p" 2>/dev/null || \
		sudo zfs create \
		 -o canmount=on \
		 -o mountpoint=legacy \
		 rpool/"$$p" ; \
	 done
	sudo zfs set \
	 com.sun:auto-snapshot=false \
	 rpool/nix
	sudo zfs set \
	 sync=always \
	 rpool/nix/var
	sudo zfs set \
	 com.sun:auto-snapshot=false \
	 rpool/var/cache
	sudo zfs set \
	 com.sun:auto-snapshot=false \
	 sync=disabled \
	 rpool/var/tmp

mermet-mount:
	# scan needed zpools
	#sudo zpool list bpool || \
	#sudo zpool import -f bpool
	sudo zpool list rpool || \
	sudo zpool import -f rpool
	# load encryption key
	zfs get -H encryption rpool | \
	grep -q '^rpool\s*encryption\s*off' || \
	zfs get -H keystatus rpool | \
	grep -q '^rpool\s*keystatus\s*available' || \
	sudo zfs load-key rpool
	# /
	sudo mkdir -p /mnt/mermet
	sudo mountpoint /mnt/mermet || \
	sudo mount -v -t zfs rpool/root /mnt/mermet
	# /boot
	sudo mkdir -p /mnt/mermet/boot
	sudo mountpoint /mnt/mermet/boot || \
	sudo mount -v $(mermet_disk)-part3 /mnt/mermet/boot
	#sudo mount -v -t zfs bpool/boot /mnt/mermet/boot
	# /boot/efi
	sudo mkdir -p /mnt/mermet/boot/efi
	sudo mountpoint /mnt/mermet/boot/efi || \
	sudo mount -v $(mermet_disk)-part2 /mnt/mermet/boot/efi
	# /*
	for p in \
	 home \
	 nix \
	 nix/var \
	 var \
	 var/cache \
	 var/log \
	 var/mail \
	 var/tmp \
	 var/www \
	 ; do \
		sudo mkdir -p /mnt/mermet/"$$p"; \
		sudo mountpoint /mnt/mermet/"$$p" || \
		sudo mount -v -t zfs rpool/"$$p" /mnt/mermet/"$$p" ; \
	 done
	sudo chmod 1777 /mnt/mermet/var/tmp

mermet-bootstrap: mermet-mount
	sudo rm -rf /mnt/mermet/etc/nixos
	#test "$$(sudo grub-probe /mnt/mermet/boot)" = zfs
	# NOTE: nixos-install will install GRUB following configuration.nix
	# BIOS
	#sudo grub-install $(mermet_disk)
	# UEFI
	#sudo grub-install \
	# --target=x86_64-efi \
	# --efi-directory=/mnt/mermet/boot/efi \
	# --bootloader-id=nixos \
	# --recheck \
	# --no-floppy
	
	pass sourcephile/mermet/dropbear/host-ecdsa.key | \
	sudo install -D -o root -g root -m 400 /dev/stdin \
	 /mnt/mermet/etc/dropbear/host-ecdsa.key && \
	test -s /mnt/mermet/etc/dropbear/host-ecdsa.key
	
	#trap "test ! -e SHRED-ME || sudo find SHRED-ME -type f -exec shred -u {} + && sudo rm -rf SHRED-ME" EXIT ;
	sudo \
	 GNUPGHOME="$$GNUPGHOME" \
	 GPG_TTY="$$GPG_TTY" \
	 LANG="$$LANG" \
	 LC_CTYPE="$$LC_CTYPE" \
	 MERMET_HOSTING="$(MERMET_HOSTING)" \
	 MERMET_MACHINE="$(MERMET_MACHINE)" \
	 NIXOS_CONFIG="$$(readlink -e ./configuration.nix)" \
	 NIX_CONF_DIR="$$NIX_CONF_DIR" \
	 NIX_PATH="$$NIX_PATH" \
	 PASSWORD_STORE_DIR="$$PASSWORD_STORE_DIR" \
	 PATH="$$PATH" \
	 SSL_CERT_FILE="$$SSL_CERT_FILE" \
	 $$(which nixos-install) \
	 --root /mnt/mermet \
	 $(if $(mermet_channel),--channel "$(mermet_channel)") \
	 --no-root-passwd \
	 --show-trace

mermet-umount:
	for p in \
	 boot/efi \
	 boot \
	 home \
	 nix/var \
	 nix \
	 var/cache \
	 var/log \
	 var/mail \
	 var/tmp \
	 var/www \
	 var \
	 "" \
	 ; do \
		! sudo mountpoint /mnt/mermet/"$$p" || \
		sudo umount -v /mnt/mermet/"$$p" ; \
	 done
	! sudo zpool list rpool 2>/dev/null || \
	zfs get -H encryption rpool | \
	grep -q '^rpool\s*encryption\s*off' || \
	zfs get -H keystatus rpool | \
	grep -q '^rpool\s*keystatus\s*unavailable' || \
	sudo zfs unload-key rpool
	#! sudo zpool list bpool 2>/dev/null || \
	#sudo zpool export bpool
	! sudo zpool list rpool 2>/dev/null || \
	sudo zpool export rpool