#!/bin/sh

set -e

COMMAND="${1:-enter}"

if [ -n "${2}" ]
then
	DISTRIBUTION="$(echo ${2} | awk -F- '{ print $1 }')"
else
	DISTRIBUTION="${2:-sid}"
fi

if [ -n "${3}" ]
then
	ARCHITECTURE="${3:-$(dpkg --print-architecture)}"
else
	ARCHITECTURE="$(echo ${2} | awk -F- '{ print $2 }')"
	ARCHITECTURE="${ARCHITECTURE:-amd64}"
fi

case "${DISTRIBUTION}" in
	buster*)
		DERIVATIVE_DISTRIBUTION="engywuck"
		;;

	bullseye*)
		DERIVATIVE_DISTRIBUTION="fuchur"
		;;

	bookworm*)
		DERIVATIVE_DISTRIBUTION="graograman"
		;;

	trixie*)
		DERIVATIVE_DISTRIBUTION="horok"
		;;
esac

MIRROR="debian.ethz.ch"

CHROOT="/srv/chroot/${DISTRIBUTION}-${ARCHITECTURE}"

Chroot ()
{
	if [ "${ARCHITECTURE}" = "$(dpkg --print-architecture)" ]
	then
		chroot "${CHROOT}" /usr/bin/env -i HOME="/root" PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin" TERM="${TERM}" ${@}
	else
		linux32 chroot "${CHROOT}" /usr/bin/env -i HOME="/root" PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin" TERM="${TERM}" ${@}
	fi
}

case "${COMMAND}" in
	create)
		if [ ! -d "${CHROOT}" ]
		then
			debootstrap --arch=${ARCHITECTURE} --include=progress-linux ${DISTRIBUTION} "${CHROOT}" http://${MIRROR}/debian
		else
			echo "${CHROOT}: file or directory already exists."
			exit 1
		fi

		# Configure apt

cat > "${CHROOT}/etc/apt/apt.conf.d/chroot.conf" << EOF
Acquire::PDiffs "false";
APT::Clean-Installed "true";
APT::Install-Recommends "false";
APT::Install-Suggests "false";
EOF

cat > "${CHROOT}/etc/apt/sources.list" << EOF
deb http://${MIRROR}/debian ${DISTRIBUTION} main contrib non-free
EOF

		case "${DISTRIBUTION}" in
			sid*)

cat >> "${CHROOT}/etc/apt/sources.list" << EOF
deb http://${MIRROR}/debian experimental main contrib non-free
EOF

				;;

			buster*)

cat > "${CHROOT}/etc/apt/sources.list.d/progress-linux.sources" << EOF
Types: deb
URIs: https://deb.progress-linux.org/packages
Suites: ${DERIVATIVE_DISTRIBUTION}-backports
Components: main contrib non-free restricted
PDiffs: no
Signed-By: /usr/share/progress-linux/pgp-keys/apt.progress-linux.org.gpg
EOF

				;;

			bullseye*|bookworm*)

cat > "${CHROOT}/etc/apt/sources.list.d/progress-linux.sources" << EOF
Types: deb
URIs: https://deb.progress-linux.org/packages
Suites: ${DERIVATIVE_DISTRIBUTION}-backports
Components: main contrib non-free restricted
PDiffs: no
Signed-By: /usr/share/progress-linux/pgp-keys/apt.progress-linux.org.gpg
EOF

				;;
		esac

		# Configure bash

cat > "${CHROOT}/etc/profile.d/chroot.sh" << EOF
#!/bin/sh

alias ls="ls --color=auto"

export DEBEMAIL="maintainers@lists.progress-linux.org"
export DEBFULLNAME="Progress Linux Maintainers"

export LANG="en_US.UTF-8"
export LANGUAGE="en_US:en"
export LC_ALL="C.UTF-8"
EOF

		# Configure dpkg
		if [ -e "${CHROOT}/etc/dpkg" ]
		then

cat > "${CHROOT}/etc/dpkg/dpkg.cfg.d/chroot" << EOF
force-unsafe-io
EOF

		fi

		if [ -e "${CHROOT}/sbin/start-stop-daemon" ]
		then
			mv "${CHROOT}/sbin/start-stop-daemon" "${CHROOT}/sbin/start-stop-daemon.orig"
		fi

cat > "${CHROOT}/sbin/start-stop-daemon" << EOF
#!/bin/sh

exit 0
EOF

		chmod 0755 "${CHROOT}/sbin/start-stop-daemon"

		# Configure sysv-rc
		if [ -e "${CHROOT}/usr/sbin/policy-rc.d" ]
		then
			mv "${CHROOT}/usr/sbin/policy-rc.d" "${CHROOT}/usr/sbin/policy-rc.d.orig"
		fi

cat > "${CHROOT}/usr/sbin/policy-rc.d" << EOF
#!/bin/sh

echo "All runlevel operations denied by policy" >&2

exit 101
EOF

		chmod 0755 "${CHROOT}/usr/sbin/policy-rc.d"

		# Configure debian
		echo "${DISTRIBUTION}_${ARCHITECTURE}" > "${CHROOT}/etc/debian_chroot"

		Chroot apt update
		Chroot apt upgrade --yes
		Chroot apt dist-upgrade --yes

		Chroot apt install --yes \
			build-essential debhelper fakeroot eatmydata

		Chroot apt install --yes \
			gnupg sudo wget

		Chroot apt install --yes \
			git rsync ca-certificates wget

		Chroot apt clean

		echo "Root password"

		Chroot "passwd"
		Chroot "adduser --home /build --ingroup sudo build"

		echo ". /etc/profile" >> "${CHROOT}/build/.bashrc"

		case $(cat /etc/hostname) in
			all*)
				BASH_HISTORY="indep"
				;;

			source*)
				BASH_HISTORY="source"
				;;

			*)
				BASH_HISTORY="arch"
				;;
		esac

		case "${BASH_HISTORY}" in
			arch)
				case "${DERIVATIVE_DISTRIBUTION}" in
					horok)
cat > "${CHROOT}/build/.bash_history" << EOF
cd */ && sudo apt-get build-dep -y . && dpkg-buildpackage -B && cd .. && rm -rf */
sudo apt-get install -y -t ${DERIVATIVE_DISTRIBUTION}-backports debhelper
clear && pbuild.sh -a -o -n -u -b binary-arch -d ${DERIVATIVE_DISTRIBUTION} -p 
rsync -aPv --progress --stats * apt.progress-linux.org::upload && rm -rf *
EOF
						;;
					*)
cat > "${CHROOT}/build/.bash_history" << EOF
cd */ && sudo apt-get build-dep -y . && dpkg-buildpackage -B && cd .. && rm -rf */
sudo apt-get install -y -t ${DERIVATIVE_DISTRIBUTION}-backports debhelper
clear && pbuild.sh -a -o -n -u -b binary-arch -d ${DERIVATIVE_DISTRIBUTION}-backports -p 
rsync -aPv --progress --stats * apt.progress-linux.org::upload && rm -rf *
EOF
						;;
				esac
				;;

			indep)

				case "${DERIVATIVE_DISTRIBUTION}" in
					horok)
cat > "${CHROOT}/build/.bash_history" << EOF
cd */ && sudo apt-get build-dep -y . && dpkg-buildpackage -A && cd .. && rm -rf */
sudo apt-get install -y -t ${DERIVATIVE_DISTRIBUTION}-backports debhelper
clear && pbuild.sh -a -o -n -u -b binary-indep -d ${DERIVATIVE_DISTRIBUTION} -p 
rsync -aPv --progress --stats * apt.progress-linux.org::upload && rm -rf *
EOF
						;;

					*)
cat > "${CHROOT}/build/.bash_history" << EOF
cd */ && sudo apt-get build-dep -y . && dpkg-buildpackage -A && cd .. && rm -rf */
sudo apt-get install -y -t ${DERIVATIVE_DISTRIBUTION}-backports debhelper
clear && pbuild.sh -a -o -n -u -b binary-indep -d ${DERIVATIVE_DISTRIBUTION}-backports -p 
rsync -aPv --progress --stats * apt.progress-linux.org::upload && rm -rf *
EOF
						;;
				esac
				;;

			source)
				case "${DERIVATIVE_DISTRIBUTION}" in
					horok)
cat > "${CHROOT}/build/.bash_history" << EOF
cd */ && sudo apt-get build-dep -y . && dpkg-buildpackage -A && cd .. && rm -rf */
sudo apt-get install -y -t ${DERIVATIVE_DISTRIBUTION}-backports debhelper
clear && pbuild.sh -o -u -b source -d ${DERIVATIVE_DISTRIBUTION} -p 
rsync -aPv --progress --stats * apt.progress-linux.org::upload && rm -rf *
EOF
						;;

					*)
cat > "${CHROOT}/build/.bash_history" << EOF
cd */ && sudo apt-get build-dep -y . && dpkg-buildpackage -A && cd .. && rm -rf */
sudo apt-get install -y -t ${DERIVATIVE_DISTRIBUTION}-backports debhelper
clear && pbuild.sh -o -u -b source -d ${DERIVATIVE_DISTRIBUTION}-backports -p 
rsync -aPv --progress --stats * apt.progress-linux.org::upload && rm -rf *
EOF
						;;
				esac
				;;
		esac

		case "${DISTRIBUTION}" in
			sid)

cat >> "${CHROOT}/build/.bash_history" << EOF
sudo apt build-dep -y .
dpkg-buildpackage --changes-option=-S
rm */ *.buildinfo *.changes *.deb *.debian.tar.xz *.dsc */ -rf
EOF

			;;
		esac

		chown 1000:1000 "${CHROOT}/build/.bash_history"*

		echo "build ALL=NOPASSWD: ALL" >> "${CHROOT}/etc/sudoers"
		;;

	chroot)
		Chroot "su - build"
		;;

	update)
		Chroot chmod 777 /dev/ptmx
		Chroot apt-get --force-yes --yes update
		Chroot apt-get --force-yes --yes upgrade
		Chroot apt-get --force-yes --yes dist-upgrade
		Chroot apt-get --force-yes --yes clean
		;;

	save)
		killall -9 syslogd > /dev/null 2>&1 || true
		killall -9 klogd > /dev/null 2>&1 || true

		for FILESYSTEM in /sys /proc /lib/init/rw /dev/shm /dev/pts /dev
		do
			umount -f "${CHROOT}/${FILESYSTEM}" > /dev/null 2>&1 || true
		done

		rm -f "${CHROOT}/root/.bash_history"
		rm -f "${CHROOT}/root/.viminfo"
		rm -f "${CHROOT}/build/.viminfo"
		rm -rf "${CHROOT}/var/tmp/vi.recover"
		rm -f "${CHROOT}/etc/machine-id"

		case $(cat /etc/hostname) in
			all*)
				BASH_HISTORY="indep"
				;;

			source*)
				BASH_HISTORY="source"
				;;

			*)
				BASH_HISTORY="arch"
				;;
		esac

		case "${BASH_HISTORY}" in
			arch)
				case "${DERIVATIVE_DISTRIBUTION}" in
					horok)
cat > "${CHROOT}/build/.bash_history" << EOF
cd */ && sudo apt-get build-dep -y . && dpkg-buildpackage -B && cd .. && rm -rf */
sudo apt-get install -y -t ${DERIVATIVE_DISTRIBUTION}-backports debhelper
clear && pbuild.sh -a -o -n -u -b binary-arch -d ${DERIVATIVE_DISTRIBUTION} -p 
rsync -aPv --progress --stats * apt.progress-linux.org::upload && rm -rf *
EOF
						;;
					*)
cat > "${CHROOT}/build/.bash_history" << EOF
cd */ && sudo apt-get build-dep -y . && dpkg-buildpackage -B && cd .. && rm -rf */
sudo apt-get install -y -t ${DERIVATIVE_DISTRIBUTION}-backports debhelper
clear && pbuild.sh -a -o -n -u -b binary-arch -d ${DERIVATIVE_DISTRIBUTION}-backports -p 
rsync -aPv --progress --stats * apt.progress-linux.org::upload && rm -rf *
EOF
						;;
				esac
				;;

			indep)

				case "${DERIVATIVE_DISTRIBUTION}" in
					horok)
cat > "${CHROOT}/build/.bash_history" << EOF
cd */ && sudo apt-get build-dep -y . && dpkg-buildpackage -A && cd .. && rm -rf */
sudo apt-get install -y -t ${DERIVATIVE_DISTRIBUTION}-backports debhelper
clear && pbuild.sh -a -o -n -u -b binary-indep -d ${DERIVATIVE_DISTRIBUTION} -p 
rsync -aPv --progress --stats * apt.progress-linux.org::upload && rm -rf *
EOF
						;;

					*)
cat > "${CHROOT}/build/.bash_history" << EOF
cd */ && sudo apt-get build-dep -y . && dpkg-buildpackage -A && cd .. && rm -rf */
sudo apt-get install -y -t ${DERIVATIVE_DISTRIBUTION}-backports debhelper
clear && pbuild.sh -a -o -n -u -b binary-indep -d ${DERIVATIVE_DISTRIBUTION}-backports -p 
rsync -aPv --progress --stats * apt.progress-linux.org::upload && rm -rf *
EOF
						;;
				esac
				;;

			source)
				case "${DERIVATIVE_DISTRIBUTION}" in
					horok)
cat > "${CHROOT}/build/.bash_history" << EOF
cd */ && sudo apt-get build-dep -y . && dpkg-buildpackage -A && cd .. && rm -rf */
sudo apt-get install -y -t ${DERIVATIVE_DISTRIBUTION}-backports debhelper
clear && pbuild.sh -o -u -b source -d ${DERIVATIVE_DISTRIBUTION} -p 
rsync -aPv --progress --stats * apt.progress-linux.org::upload && rm -rf *
EOF
						;;
					*)
cat > "${CHROOT}/build/.bash_history" << EOF
cd */ && sudo apt-get build-dep -y . && dpkg-buildpackage -A && cd .. && rm -rf */
sudo apt-get install -y -t ${DERIVATIVE_DISTRIBUTION}-backports debhelper
clear && pbuild.sh -o -u -b source -d ${DERIVATIVE_DISTRIBUTION}-backports -p 
rsync -aPv --progress --stats * apt.progress-linux.org::upload && rm -rf *
EOF
						;;
				esac
				;;
		esac

		case "${DISTRIBUTION}" in
			sid)

cat >> "${CHROOT}/build/.bash_history" << EOF
sudo apt build-dep -y .
dpkg-buildpackage --changes-option=-S
rm */ *.buildinfo *.changes *.deb *.debian.tar.xz *.dsc */ -rf
EOF

			;;
		esac

		if [ -e "${CHROOT}/build/.bash_history.orig" ]
		then
			rm -f "${CHROOT}/build/.bash_history"
			cp -a "${CHROOT}/build/.bash_history.orig" "${CHROOT}/build/.bash_history"
		fi

		rsync -av --delete "${CHROOT}"/ "${CHROOT}".orig

		mount proc-$(basename ${CHROOT}) "${CHROOT}/proc" -t proc
		mount devpts-$(basename ${CHROOT}) "${CHROOT}/dev/pts" -t devpts
		mount sysfs-$(basename ${CHROOT}) "${CHROOT}/sys" -t sysfs
		mount /dev/shm -o bind "${CHROOT}/dev/shm"
		;;

	restore)
		killall -9 syslogd > /dev/null 2>&1 || true
		killall -9 klogd > /dev/null 2>&1 || true

		for FILESYSTEM in /sys /proc /lib/init/rw /dev/shm /dev/pts /dev
		do
			umount -f "${CHROOT}/${FILESYSTEM}" > /dev/null 2>&1 || true
		done

		rsync -av --delete "${CHROOT}".orig/ "${CHROOT}"

		mount proc-$(basename ${CHROOT}) "${CHROOT}/proc" -t proc
		mount devpts-$(basename ${CHROOT}) "${CHROOT}/dev/pts" -t devpts
		mount sysfs-$(basename ${CHROOT}) "${CHROOT}/sys" -t sysfs
		mount /dev/shm -o bind "${CHROOT}/dev/shm"
		;;

	reset)
		"${0}" restore ${DISTRIBUTION} ${ARCHITECTURE}
		"${0}" update ${DISTRIBUTION} ${ARCHITECTURE}
		"${0}" save ${DISTRIBUTION} ${ARCHITECTURE}
		;;

	*)
		echo "Wrong option."
		exit 1
esac