base.sh

#!/bin/bash

if [ -d "/shells/software/qemu-8.2.9/bin" ]; then
	export PATH="/shells/software/qemu-8.2.9/bin:$PATH"
fi
QEMUIMG="$(command -v qemu-img)"
QEMUSD="$(command -v qemu-storage-daemon)"
NBDCL="$(command -v nbd-client)"

# various settings
NBD="/dev/nbd2"
RESDIR="$PWD/res"
SCRIPTSDIR="$PWD/scripts"
TMPIMG="work$$.qcow2"
API_PREFIX="https://ws.atonline.com/_special/rest/"
BLOCKSIZE=512

if [ -d /shells ]; then
	WORK="/shells/work"
else
	WORK="$PWD/work"
fi

if [ x"$USER" = x"root" ]; then
	modprobe nbd
fi

DATE=$(date +'%Y%m%d')

perform_clean() {
	if [ -d "$WORK" ]; then
		fuser --kill --ismountpoint --mount "$WORK" && sleep 1 || true
		umount 2>/dev/null "$WORK/var/cache/apt/archives" || true
		umount 2>/dev/null "$WORK/proc" "$WORK/sys" "$WORK/dev/pts" "$WORK/dev" || umount 2>/dev/null -l "$WORK/proc" "$WORK/sys" "$WORK/dev" || true
		umount 2>/dev/null "$WORK" || true
		"$NBDCL" 2>/dev/null -d "$NBD" || true
		killall qemu-storage-daemon || true
		# should be empty after umount
		rmdir "$WORK"
	fi
}

create_empty() {
	perform_clean

	echo "Creating and partitionning $TMPIMG..."
	"$QEMUIMG" create -f qcow2 "$TMPIMG" 10G
	"$QEMUSD" --daemonize --pidfile qemusd.$$.pid --blockdev "driver=qcow2,file.driver=file,file.filename=$TMPIMG,node-name=disk0" --nbd-server addr.type=unix,addr.path=/tmp/nbd.sock --export type=nbd,id=exp0,node-name=disk0,name=disk0,writable=on
	"$NBDCL" -unix /tmp/nbd.sock -N disk0 -b "$BLOCKSIZE" "$NBD"
	sleep 0.5
	parted --script -a optimal -- "$NBD" mklabel gpt mkpart primary ext4 1MiB -2048s
	sleep 0.5 # wait for /dev to update
	echo "Formatting and mounting..."
	mkfs.ext4 -L root "$NBD"p1
	mkdir "$WORK"
	mount "$NBD"p1 "$WORK"
}

prepare() {
	perform_clean

	if [ x"$1" != x ]; then
		echo '*****'
		echo "** Preparing new environment based on $1"
		echo '*****'

		if [ -f "$1".tar.xz ]; then
			create_empty
			echo "Extracting..."
			tar xp -C "$WORK" -f "$1".tar.xz
		elif [ -f "$1" ]; then
			# let tar determine the right format
			create_empty
			echo "Extracting..."
			tar xp -C "$WORK" -f "$1"
		elif [ -f "$1".qcow2 ]; then
			cp -v "$1".qcow2 "$TMPIMG"

			# mount
			mkdir "$WORK"
			"$QEMUSD" --daemonize --pidfile qemusd.$$.pid --blockdev "driver=qcow2,file.driver=file,file.filename=$TMPIMG,node-name=disk0" --nbd-server addr.type=unix,addr.path=/tmp/nbd.sock --export type=nbd,id=exp0,node-name=disk0,name=disk0,writable=on
			"$NBDCL" -unix /tmp/nbd.sock -N disk0 -b "$BLOCKSIZE" "$NBD"
			sleep 1
			mount "$NBD"p1 "$WORK"
		else
			echo "Could not find base for $1"
		fi

		# mount proc, sys, dev
		mount -t proc proc "$WORK/proc"
		mount -t sysfs sys "$WORK/sys"
		mount -t devtmpfs udev "$WORK/dev"
		mkdir -p "$WORK/dev/pts"
		mount -t devpts devpts "$WORK/dev/pts"

		# prevent service activation (will be deleted by finalize)
		echo -e '#!/bin/sh\nexit 101' >"$WORK/usr/sbin/policy-rc.d"
		chmod +x "$WORK/usr/sbin/policy-rc.d"
	else
		echo '*****'
		echo "** Preparing new environment"
		echo '*****'

		create_empty
	fi
}

run() {
	chroot "$WORK" "$@"
}

finalize() {
	echo '*****'
	echo "** Generating disk image $1-$DATE"
	echo '*****'
	rm -f "$WORK/usr/sbin/policy-rc.d"

	# erase those files only if not symlinks
	for foo in /etc/machine-id /var/lib/dbus/machine-id; do
		if [ -f "$WORK$foo" ] && [ ! -L "$WORK$foo" ]; then
			rm -f "$WORK$foo"
		fi
	done
	echo localhost >"$WORK/etc/hostname"

	# generate /etc/shells-release file
	cat >"${WORK}/etc/shells-release" <<EOF
# file automatically generated by Shells
SHELLS_IMAGE_TAG="$DATE"
SHELLS_IMAGE_CODE="$1"
SHELLS_IMAGE_TIMESTAMP="$(date +%s)"
EOF

	# making sure we have no remaining process
	fuser --kill --ismountpoint --mount "$WORK" && sleep 1 || true

	# unmount all mounts under $WORK (in reverse order, deepest first)
	grep " $WORK/" /proc/self/mounts | cut -d' ' -f2 | sort -r | while read mnt; do
		umount "$mnt" 2>/dev/null || umount -l "$mnt" 2>/dev/null || true
	done

	# build squashfs image
	mksquashfs "$WORK" "$1-$DATE.squashfs" -comp xz -noappend -progress

	echo "Syncing..."
	umount "$WORK"
	"$NBDCL" -d "$NBD"
	sleep 0.5
	if [ -f qemusd.$$.pid ]; then
		kill $(cat qemusd.$$.pid )
		sleep 0.5
	fi

	"$QEMUIMG" convert -c -p -f qcow2 -O qcow2 "work$$.qcow2" "$1-$DATE.qcow2"
	mv -f "work$$.qcow2" "$1.qcow2"

	if [ ! -d rbdconv ]; then
		# grab rbdconv
		git clone https://github.com/Shells-com/rbdconv.git
	fi
	# need to convert to raw file first so that raw-to-rbd.php can get the filesize first
	"$QEMUIMG" convert -f qcow2 -O raw "$1-$DATE.qcow2" "$1-$DATE.raw"
	php rbdconv/raw-to-rbd.php "$1-$DATE.raw" | xz -z -9 -T $(nproc --ignore=4) -v >"$1-$DATE.shells"
	rm -f "$1-$DATE.raw"

	go run github.com/KarpelesLab/rest/cli/restupload@latest -api Shell/OS:uploadOfficialImage -params "blocksize=$BLOCKSIZE" "$1-$DATE.qcow2" "$1-$DATE.squashfs" "$1-$DATE.shells"

	# complete, list the file
	ls -la "$1-$DATE.qcow2"
}

add_firstrun() {
	# add first run process before sysinit but after network
	cp "$SCRIPTSDIR/firstrun.sh" "$WORK/.firstrun.sh"
	chmod +x "$WORK/.firstrun.sh"

	local AFTER="$1"
	if [ x"$AFTER" = x ]; then
		# can also be NetworkManager-wait-online.service
		AFTER="network-online.target"
	fi

	if [ -d "$WORK/usr/lib/systemd/system" ]; then
		# systemd method
		cat >"$WORK/usr/lib/systemd/system/cloud-firstrun.service" <<EOF
[Unit]
Description=Cloud firstrun handler
ConditionFileIsExecutable=/.firstrun.sh
After=$AFTER
Wants=$AFTER
Before=network-online.target
Before=sshd-keygen.service
Before=sshd.service
Before=systemd-user-sessions.service

[Service]
Type=oneshot
ExecStart=/.firstrun.sh start
TimeoutSec=0
RemainAfterExit=yes
StandardOutput=journal+console

[Install]
WantedBy=sysinit.target
EOF
		# enable
		run systemctl enable cloud-firstrun
	else
		echo "No systemd found!"
		exit 1
	fi
}