#!/usr/bin/env zsh
#
# Copyright (C) 2016 Dyne.org Foundation
#
# ARM SDK is designed, written and maintained by parazyd <parazyd@dyne.org>
#
# This source code is free software; you can redistribute it and/or
# modify it under the terms of the GNU Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# This source code is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  Please refer
# to the GNU Public License for more details.
#
# You should have received a copy of the GNU Public License along with
# this source code; if not, write to: Free Software Foundation, Inc.,
# 675 Mass Ave, Cambridge, MA 02139, USA.
#
# Common functions for builds

writebase="$strapdir"
command -v dcfldd >/dev/null && DD=`command -v dcfldd`
DD=${DD:-/bin/dd}

write-hostname() {
	fn write-hostname

	print $os | sudo tee ${writebase}/etc/hostname
	notice "Wrote $writebase/etc/hostname"
}

write-fstab() {
	fn write-fstab

	notice "Writing fstab"
	cat <<EOF | sudo tee ${workdir}/root/etc/fstab
# <file system> <mount point> <type> <options> <dump> <pass>
proc /proc proc nodev,noexec,nosuid 0 0
/dev/mmcblk0p2 / ext4 errors=remount-ro 0 1
/dev/mmcblk0p1 /boot vfat noauto 0 0
EOF
}

write-hosts-file() {
	fn write-hosts-file

	cat <<EOF | sudo tee ${writebase}/etc/hosts
127.0.0.1    ${os}              localhost
::1          localhost          ip6-localhost ip6-loopback
fe00::0      ip6-localnet
fe00::0      ip6-mcastprefix
fe02::1      ip6-allnodes
fe02::1      ip6-allrouters
EOF
	notice "Wrote $writebase/etc/hosts"
}

write-network-ifaces() {
	fn write-hosts-file

	cat <<EOF | sudo tee ${writebase}/etc/network/interfaces
auto lo
iface lo inet loopback

auto eth0
iface eth0 inet dhcp
EOF
	notice "Wrote $writebase/etc/network/interfaces"
}

write-resolvconf() {
	fn write-resolvconf

	cat <<EOF | sudo tee ${writebase}/etc/resolv.conf
# foebud and ccc dns
nameserver 85.214.20.141
nameserver 213.73.91.35
EOF
	notice "Wrote $writebase/etc/resolv.conf"
}

write-debconf() {
	fn write-debconf

	cat <<EOF | sudo tee ${writebase}/debconf.set
console-common console-data/keymap/policy select Select keymap from full list
console-common console-data/keymap/full select en-latin1-nodeadkeys
EOF
	[[ $? = 0 ]] || error "Failed writing $writebase/debconf.set"
}

write-cleanup() {
	fn write-cleanup

	cat <<EOF | sudo tee ${writebase}/cleanup
#!/bin/bash
rm -rf /root/.bash_history
apt-get update
apt-get clean
rm -f /0
rm -f /hs_err*
rm -f cleanup
rm -f /usr/bin/qemu*
EOF
	sudo chmod +x $writebase/cleanup
	notice "Wrote $writebase/cleanup"
}

write-sources-list() {
	fn write-sources-list

	cat <<EOF | sudo tee ${writebase}/$1etc/apt/sources.list
deb ${mirror} ${release} ${section}
deb-src ${mirror} ${release} ${section}
EOF
	notice "Wrote $writebase/etc/apt/sources.list"
}

write-third-stage() {
	fn write-third-stage

	cat <<EOF | sudo tee ${writebase}/third-stage
#!/bin/bash
dpkg-divert --add --local --divert /usr/sbin/invoke-rc.d.chroot --rename /usr/sbin/invoke-rc.d
cp /bin/true /usr/sbin/invoke-rc.d
echo -e "#!/bin/sh\nexit 101" > /usr/sbin/policy-rc.d
chmod +x /usr/sbin/policy-rc.d

apt-get update
apt-get --yes --force-yes install locales-all

debconf-set-selections /debconf.set
rm -f /debconf.set
apt-get update
apt-get -y install ${core_packages}

echo "root:toor" | chpasswd
sed -i -e 's/KERNEL\!=\"eth\*|/KERNEL\!=\"/' /lib/udev/rules.d/75-persistent-net-generator.rules
rm -fv /etc/udev/rules.d/70-persistent-net.rules
export DEBIAN_FRONTEND=noninteractive

apt-get --yes --force-yes install ${base_packages}
apt-get --yes --force-yes install ${system_packages}
apt-get --yes --force-yes install ${extra_packages}

apt-get --yes --force-yes dist-upgrade
apt-get --yes --force-yes autoremove

echo "Allowing SSH root login"
sed -i -e 's/PermitRootLogin without-password/PermitRootLogin yes/' /etc/ssh/sshd_config
update-rc.d ssh enable

rm -fv /usr/sbin/policy-rc.d
rm -fv /usr/sbin/invoke-rc.d
dpkg-divert --remove --rename /usr/sbin/invoke-rc.d

rm -fv /third-stage
EOF
	sudo chmod +x $writebase/third-stage
	notice "Wrote $writebase/third-stage"
}

${device_name}-bootstrap() {
	fn ${device_name}-bootstrap

	notice "Bootstrapping $os base"
	mkdir -p ${workdir}
	cd ${workdir}

	sudo debootstrap --foreign --arch ${arch} ${release} ${strapdir} ${mirror}
	[[ $? = 0 ]] || {
		error "debootstrap failed"
		return 1
	}

	# qemu-wrapper
	[[ $enable_qemu_wrapper = 1 ]] && {
		sudo cp $R/arm/qemu-wrapper ${strapdir}/usr/bin/ && notice "Copied qemu-wrapper"
		print ':arm:M::\x7fELF\x01\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x28\x00:\xff\xff\xff\xff\xff\xff\xff\x00\xff\xff\xff\xff\xff\xff\xff\xff\xfe\xff\xff\xff:/qemu-wrapper:' \
			| sudo tee /proc/sys/fs/binfmt_misc/register
	}

	sudo cp -rfv ${qemu_bin} ${strapdir}/usr/bin/ && notice "Success bootstrapping base"
	[[ $? = 0 ]] || return 1
	notice "Next step is "${device_name}-secondstage
}

${device_name}-secondstage() {
	fn ${device_name}-secondstage

	notice "Bootstrapping $os second-stage"
	LANG=C sudo -E chroot ${strapdir} /debootstrap/debootstrap --second-stage
	[[ $? = 0 ]] || {
		error "debootstrap second-stage failed"
		return 1
	}

	write-sources-list
	write-hostname
	write-hosts-file
	write-network-ifaces
	write-resolvconf
	write-debconf
	write-third-stage

	notice "Finished second-stage"
	notice "Next step is: ${device_name}-thirdstage"
}

${device_name}-thirdstage() {
	fn ${device_name}-thirdstage

	notice "Bootstrapping $os third-stage"

	export LC_ALL=C
	export DEBIAN_FRONTEND=noninteractive

	sudo -E mount -t proc proc ${strapdir}/proc && notice "Mounted proc..."
	sudo -E mount -o bind /dev/ ${strapdir}/dev/ && notice "Mounted dev..."
	sudo -E mount -o bind /dev/pts ${strapdir}/dev/pts && notice "Mounted dev/pts..."

	notice "Chrooting..."
	LANG=C sudo -E chroot $strapdir /third-stage
	[[ $? = 0 ]] || {
		error "Failed at third-stage"
		return 1
	}

	write-cleanup
	notice "Executing cleanup..."
	LANG=C sudo -E chroot ${strapdir} /cleanup
	[[ $? = 0 ]] || {
		error "Failed at cleanup"
		return 1
	}

	copy-zram

	sudo umount ${strapdir}/dev/pts && notice "Unmounted dev/pts"
	sleep 5
	sudo umount ${strapdir}/dev && notice "Unmounted dev"
	sleep 2
	sudo umount ${strapdir}/proc && notice "Unmounted proc"
	sleep 2
	notice "Finalized third-stage"
	notice "Next step is: ${device_name}-prepimg"
}

${device_name}-prepimg() {
	fn ${device_name}-prepimg

	notice "Creating image file..."
	$DD if=/dev/zero \
		of=${image_name}.img \
		bs=1M count=$size

	notice "Partitioning..."
	if [[ $gpt == 1 ]]; then
		parted ${image_name}.img --script -- mklabel gpt
		cgpt create -z ${image_name}.img
		cgpt create ${image_name}.img
		cgpt add -i 1 -t kernel -b 8192 -s 32768 -l kernel -S 1 -T 5 -P 10 ${image_name}.img
		cgpt add -i 2 -t data -b 40960 -s `expr $(cgpt show ${image_name}.img \
			| grep 'Sec GPT table' \
			| awk '{print \$1}') - 40960` -l Root ${image_name}.img

		loopdevice=`sudo losetup -f --show ${workdir}/${image_name}.img`
		mappdevice=`sudo kpartx -va $loopdevice | sed -E 's/.*(loop[0-9])p.*/\1/g' | head -1`
		notice "Loopdevice: $loopdevice"
		notice "Mapper device: $mappdevice"

		warn "Do not think of purple hippos" && sleep 5

		mappdevice="/dev/mapper/${mappdevice}"
		bootpart=${mappdevice}p1
		rootpart=${mappdevice}p2

		notice "Formatting partitions..."
		mkfs.ext4 -L rootfs $rootpart

		mkdir -p ${workdir}/root
		sudo mount $rootpart ${workdir}/root && notice "Mounted root part"

		for i in $custmodules; do print $i | sudo tee -a ${strapdir}/etc/modules ; done
	else
		parted ${image_name}.img --script -- mklabel msdos
		parted ${image_name}.img --script -- mkpart primary ${parted_boot}
		parted ${image_name}.img --script -- mkpart primary ${parted_root}

		loopdevice=`sudo losetup -f --show ${workdir}/${image_name}.img`
		mappdevice=`sudo kpartx -va $loopdevice | sed -E 's/.*(loop[0-9])p.*/\1/g' | head -1`
		notice "Loopdevice: $loopdevice"
		notice "Mapper device: $mappdevice"

		warn "Do not think of purple hippos" && sleep 5

		mappdevice="/dev/mapper/${mappdevice}"
		bootpart=${mappdevice}p1
		rootpart=${mappdevice}p2

		notice "Formatting partitions..."
		sudo mkfs.vfat $bootpart
		sudo mkfs.ext4 $rootpart

		mkdir -p ${workdir}/bootp ${workdir}/root
		sudo mount $bootpart ${workdir}/bootp && notice "Mounted boot part"
		sudo mount $rootpart ${workdir}/root && notice "Mounted root part"

		print ${inittab} | sudo tee -a ${strapdir}/etc/inittab
		for i in $custmodules; do print $i | sudo tee -a ${strapdir}/etc/modules ; done
	fi

	notice "Finalized preparing image"
	notice "Next step is ${device_name}-build-kernel"
}

${device_name}-pack-image() {
	fn ${device_name}-pack-image

	notice "Rechecking filesystem"
	sudo e2fsck -f ${mappdevice}p2
	sudo resize2fs ${mappdevice}p2

	sudo kpartx -dv $loopdevice
	[[ $? = 0 ]] || error "kpartx failed to remove $loopdevice"
	sudo losetup -d $loopdevice
	[[ $? = 0 ]] || error "losetup failed to remove $loopdevice"

	notice "Compressing image to xz"
	xz -zv ${image_name}.img

	notice "Generating sha256 for ${image_name}.img.xz"
	sha256sum ${image_name}.img.xz > ${image_name}.img.xz.sha

	[[ -d $R/arm/finished ]] || mkdir -p $R/arm/finished
	mv -v ${image_name}.img.xz $R/arm/finished/
	mv -v ${image_name}.img.xz.sha $R/arm/finished/

	cd $R
	sudo rm -r ${strapdir}
	sudo rm -r ${workdir}

	notice "Finished building ${image_name}"
}

get-kernel-firmware() {
	[[ -d $R/tmp/firmware ]] || git clone \
		https://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git $R/tmp/firmware
		rm -rf $R/tmp/firmware/.git
}

clean-kernel-leftovers() {
	notice "Cleaning up from kernel build..."
	sudo rm -r ${strapdir}/usr/src/kernel
	sudo rm ${strapdir}/usr/src/${device_name}.config
	#sudo rm ${strapdir}/usr/src/kernel-at-commit

	sudo chown root ${strapdir}/lib
	sudo chown -R root ${strapdir}/lib/modules
	sudo chown -R root ${strapdir}/lib/firmware

	cd ${workdir}
}

copy-kernel-config() {
	cd ${strapdir}/usr/src/kernel

	cp -v ${workdir}/../kernel-configs/${device_name}.config .config
	sudo cp -v ${workdir}/../kernel-configs/${device_name}.config ../${device_name}.config

	export ARCH=arm
	export CROSS_COMPILE=${compiler}
}

make-kernel-modules() {
	[[ -d ${strapdir}/lib/modules ]] || sudo mkdir -p ${strapdir}/lib/modules
	[[ -d ${strapdir}/lib/firmware ]] || sudo mkdir -p ${strapdir}/lib/firmware
	sudo chown -R $USER ${strapdir}/lib/modules
	sudo chown -R $USER ${strapdir}/lib/firmware
	make modules_install INSTALL_MOD_PATH=${strapdir}
	[[ $? = 0 ]] || {
		error "Failed installing kernel modules"
		return 1
	}
}

copy-zram() {
	notice "Installing zram init"
	sudo cp ${workdir}/../extra/zram ${strapdir}/etc/init.d/zram
	sudo chmod +x ${strapdir}/etc/init.d/zram
}

${device_name}-finalize() {
	fn ${device_name}-finalize

	clean-kernel-leftovers

	notice "Making you wait for nothing..."
	sudo rsync -HPavz -q ${strapdir}/* ${workdir}/root

	writebase="${workdir}/root"
	write-sources-list
	write-fstab

	cd ${workdir}

	sudo umount ${bootpart} && notice "Unmounted boot part"
	sudo umount ${rootpart} && notice "Unmounted root part"

	notice "Finalized build..."
	notice "Pack and finish with: ${device_name}-pack-image"
}

${device_name}-build-all() {
	for i in bootstrap secondstage thirdstage prepimg build-kernel finalize pack-image; do
		${device_name}-${i}
		[[ $? = 0 ]] || {
			error "Failed on ${device_name}-${i}"
			return 1
		}
	done
}

[[ -f ${qemu_bin} ]] || warn "No ${qemu_bin}"
notice "Loaded build script for ${device_name}"
notice "Run '${device_name}-bootstrap' to build step by step"
notice "Run '${device_name}-build-all' to build image automatically"