#!/usr/bin/env ruby

require 'pathname'
$: << Pathname.new($0).expand_path.dirname+'lib'
require 'base'
require 'active_support/all'

Sector = Sectors = 512

class Armbian2LVM_XFS < Base
	def initialize
		super
		chs = [?a..?z, ?A..?Z].map(&:to_a).flatten
		@vgname = "armbian_#{5.times.map{chs[rand(chs.length)]}.join}"
		d "Destination image «#{dest.image}» in use!", dest.kpartxed?
	end

	# read from input, write to output
	# input|output can be:
	#   Pathname:   opens file and use it as IO
	#   String:     reads from/writes to like an IO (->StringIO)
	#   IO:         use it directly
	# obs|ibs|bs: blocksizes (if ibs|obs not given, bs will be used, else 512)
	# from:       set input-block-position to from
	# skip:       skip next X blocks from current position
	# at:         set output-block-position to to
	# seek:       seek to next X blocks from current position
	def dd input, output, from: nil, skip: nil, at: nil, seek: nil, bs: nil, ibs: nil, obs: nil
		case input
		when Pathname
			input.open 'r' do |f|
				return __method__( f, output, pos: pos, seek: seek)
			end
		when String
			StringIO.open input do |f|
				return __method__( f, output, pos: pos, seek: seek)
			end
		when IO

			case output
			when Pathname
				output.open 'w' do |f|
					return __method__( input, f, pos: pos, seek: seek)
				end
			when String
				StringIO.open output, 'w' do |f|
					return __method__( input, f, pos: pos, seek: seek)
				end
			when IO

				ibs ||= bs || 512
				obs ||= bs || 512
				input.pos   = from*ibs  if from
				input.pos  += skip*ibs  if skip
				output.pos  = at*obs    if at
				output.pos += seek*obs  if seek
				output.write input.read( count ? count*ibs : nil)

			end

		else
			raise ArgumentError, "input for dd must be a String, IO or Pathname"
		end
	end

	def run
		mkmppaths

		d "Base image does not exist", base.image.exist?
		base_parts = base.kpartx
		d "two (root-)partition in base expected, got: #{base_parts.inspect}", 1 == base_parts.length

		mount base_parts[0], base.root, -:oro

		msg 'prepare image', dest.image
		dest.image.open 'w' do |f|
			f.truncate 0
			f.pos = 0
			f.write 0.chr*4.megabytes
			f.pos = 1.5.gigabytes+128.megabytes+4.megabytes-1
			f.putc 0.chr
		end
		# partitions for: /boot (128MiBi), LVM
		sh.parted dest.image, '--',
			*%w[mklabel msdos],
			*%w[mkpart primary ext2    4MB 132MB],
			*%w[mkpart primary ext2  132MB  -4MB],
			*%w[set 1 boot on],
			*%w[set 2 LVM on],
			*%w[print]

		ubootdir = base.root + 'usr' + 'lib' + 'linux-u-boot-dev-odroidxu4_5.34.171103_armhf'
		if false
			sh.bash -:ec, <<-EOF.gsub( /^\t{4}/, '').sub( /\n$/m, '')
				echo "hallo welt"
				BRANCH=dev
				source ./build/config/sources/odroidxu4.conf
				dd() {
					echo dd "$*" >&2
					command dd "$@"
				}
				write_uboot_platform #{ubootdir.to_s.shellescape} #{dest.image.to_s.shellescape}
			EOF
		else
			msg 'install u-boot', dest.image, ubootdir
			dest.image.open 'r+' do |f|
				msg '  apply', ubootdir+'bl1.bin.hardkernel'
				f.pos =    1*Sector
				b = (ubootdir+'bl1.bin.hardkernel').read
				f.write b
				msg '  apply', ubootdir+'bl2.bin.hardkernel.720k_uboot'
				f.pos =   31*Sectors
				f.write (ubootdir+'bl2.bin.hardkernel.720k_uboot').read
				msg '  apply', ubootdir+'u-boot-dtb.bin'
				f.pos =   63*Sectors
				f.write (ubootdir+'u-boot-dtb.bin').read
				msg '  apply', ubootdir+'tzsw.bin.hardkernel'
				f.pos = 1503*Sectors
				f.write (ubootdir+'tzsw.bin.hardkernel').read
				msg '  clear', 'u-boot env'
				f.pos = 2015*Sectors
				f.write 0.chr*32*Sectors
			end
		end

		dest_parts = dest.kpartx
		d "two partitions in destination expected", 2 == dest_parts.length

		#root = MP.new self, dest_parts[1], dest.root
		#home = MP.new self, nil, dest.root+'home'
		#boot = MP.new self, dest_parts[0], dest.root+'boot'

		vgpath = Pathname.new( '/dev') + vgname
		root = MP.new self, vgpath + 'root', dest.root
		#home = MP.new self, vgpath + 'home', dest.root+'home'
		boot = MP.new self, dest_parts[0], dest.root+'boot'
		#swap = MP.new self, vgpath + 'swap', 'none'
		
		sh.pvcreate dest_parts[1]
		sh.vgcreate vgname, dest_parts[1]
		sh.lvcreate -:nroot, '-L1.5G', vgname
		#sh.lvcreate -:nhome, '-L120M', vgname
		#sh.lvcreate -:nswap, '-L10M', vgname
		activate_vg vgname
		sh.mkext4fs boot.dev
		sh.mkxfs root.dev
		#sh.mkxfs home.dev
		#sh.mkswap swap.dev

		root.mount
		#home.mp.mkdir
		#home.mount
		boot.mp.mkdir
		boot.mount

		exclude = %w[boot/dtb-*
			boot/uInitrd-* boot/vmlinuz-* boot/initrd.img-*
			boot/config-* boot/System.map-*
			etc/systemd/system/basic.target.wants/resize2fs.service
			etc/systemd/system/sysinit.target.wants/log2ram.service
			etc/rc?.d/*resize2fs
			root/.not_logged_in_yet etc/profile.d/check_first_login.sh
		].flat_map {|e| ['--exclude', e] } #"#{base.root}#{e}"] }

		sh.rsync_all *exclude, "#{base.root}/", root.mp

		msg 'create symlink', boot.mp+'boot', '->', '.'
		(boot.mp+'boot').make_symlink '.'
		manipulate_file boot.mp+'boot.ini' do |file, &push|
			file.each_line do |l|
				case l.chomp!
				when /^ *setenv +rootdev +/
					push.call "setenv rootdev \"UUID=#{root.uuid}\""
				when /^ *setenv +rootfstype +/
					push.call "setenv rootfstype \"#{root.fstype}\""
				else
					push.call l
				end
			end
		end

		manipulate_file root.mp+'etc'+'initramfs-tools'+'initramfs.conf' do |file, &push|
			file.each_line do |l|
				case l.chomp!
				when /^COMPRESS=/
					push.call 'COMPRESS=xz'
				when /^# *COMPRESS=/
					push.call l, 'COMPRESS=xz'
				else
					push.call l
				end
			end
		end

		manipulate_file root.mp+'etc'+'fstab' do |file, &push|
			file.each_line do |l|
				case l.chomp!
				when /^ *#/
					push.call l
				when /^\s*(\S+)\s+\/\s+()/
					push.call "UUID=#{root.uuid} / #{root.fstype} defaults,noatime,nodiratime,errors=remount-ro 0 1"
				when /^\s*\/var\/swap\s+/
					# skip
				else
					push.call l
				end
			end
			#push.call "UUID=#{swap.uuid} none  #{swap.fstype} sw 0 0"
			push.call "UUID=#{boot.uuid} /boot #{boot.fstype} defaults 0 0"
			#push.call "UUID=#{home.uuid} /home #{home.fstype} defaults,errors=remount-ro 0 0"
		end

		sh.tar -:C, root.mp, -:xf, 'files.tar'  if File.exists? 'files.tar'

	rescue ProgrammError
		err $!
		raise
	ensure
		STDERR.puts "="*80
		umount_all ignore_exceptions: true
		deactivate_all_vgs ignore_exceptions: true
		capsulated_rescue { sh.sync }
		capsulated_rescue { dest.departx }
		capsulated_rescue { base.departx }
		capsulated_rescue { sh.sync }
	end
end

Armbian2LVM_XFS.new.run