#!/bin/bash

# For some reason, building chroots for buster from stretch requires libdebian-installer4 0.119 instead of 0.110, c.f. https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=904699 ... installed it by manually downloading and dpkg -i the .deb
readonly DISTRIB=buster
readonly INIT_DIR=$PWD
#readonly ARCHS="amd64"
#readonly ARCHS="i386 armhf armel arm64"
readonly ARCHS="arm64"

function main()
{
    for ARCH in $ARCHS
    do
        build_chroot $ARCH
    done
}

function build_chroot()
{
    local ARCH=$1
    local CHROOT=chroot-${DISTRIB}-${ARCH}

    echo ""
    echo "Starting build for $ARCH"
    echo ""

    cd /tmp/
    cdebootstrap --arch=${ARCH} --foreign ${DISTRIB} ./$CHROOT http://deb.debian.org/debian/
    cp /usr/bin/qemu-arm-static $CHROOT/usr/bin/
    cp /usr/bin/qemu-aarch64-static $CHROOT/usr/bin/
    cp /etc/resolv.conf $CHROOT/etc/resolv.conf 

    chroot $CHROOT apt update
    chroot $CHROOT apt dist-upgrade
    chroot $CHROOT apt install -y build-essential debhelper cmake wget devscripts

    if [ "$ARCH" == "amd64" ];
    then
        chroot $CHROOT wget https://github.com/tj/n/archive/v4.1.0.tar.gz
        chroot $CHROOT tar -xvzf v4.1.0.tar.gz
        chroot $CHROOT /bin/bash -c "cd n-4.1.0; make install"
        chroot $CHROOT n 10 # We take nodjes version 10 because idk
    fi

    chroot $CHROOT apt clean

    cd $CHROOT
    echo "Now creating tarball with the filesystem ..."
    tar -czf $INIT_DIR/${DISTRIB}-${ARCH}.tgz ./*

    echo ""
    echo "Output chroot archive should be available as $INIT_DIR/${DISTRIB}-${ARCH}.tgz"
    echo ""
}

main