#!/bin/bash

link() {
    ls -l $1 | cut -d '>' -f 2- | cut -d ' ' -f 2
}

injectFileAndLink() {
    local b=$(basename $1)
    local d=$(dirname $1)
    local l

    #echo "--> $1"

    [ ! -d $DST/$d ] && mkdir -p $DST/$d
    [ ! -e $DST/$1 ] && {
        #echo "cp $1 $DST/$1"
        cp -a $1 $DST/$1
    }


    if [ -L $1 ]; then
        l=$(link $1)

        # Absolute link
        if ! echo $l | grep -q '^/'; then
            l=$d/$l
        fi

        injectFileAndLink $l
    fi
}

injectDepends() {

    local b d l ld

    #echo "deps : $1"

    ! file $1 | grep -q 'dynamically linked' && return

    # Dynmamic linker

    l=$(ldd $1 | grep -v '=>' | grep ld-linux | sed -re 's/^[[:space:]]*//'  | cut -d ' ' -f 1)

    #echo "   $l"

    injectFileAndLink $l

    # Libraries

    for l in $(ldd $1 | grep '=>' | cut -d '>' -f 2 | cut -d ' ' -f 2); do
        #echo " -> $l"
        injectFileAndLink $l
    done
}

injectCommandWithDepends() {
    local f=$1

    if ! echo $1 | grep -q '/'; then
        f=$(whereis -b -B $SEARCH_DIRS -f $1 | cut -d ' ' -f 2)
    fi

    #echo "*** $f"

    [ -z "$f" ] && error "Command $f not found in $SEARCH_DIRS !"

    injectFileAndLink $f
    injectDepends $f

    if [ -L $f ]; then
        f=$(link $f)
        injectCommandWithDepends $f
    fi
}

getRandomPasswd() {
    local k

    while :; do
        k=$(tr -dc _A-Z-a-z-0-9 < /dev/urandom 2> /dev/null | head -c${1:-32} )
        if [ $(echo -n $k | wc -c) = 32 ]; then
            break
        fi
        echo "Wait for entropy avail : $(cat /proc/sys/kernel/random/entropy_avail)" >&2
        sleep 1
    done
    echo -n $k
}



debootstrap() {

	#if [ -e $VDN_PATH/files/$HDA ]; then
	#	echo "Warning : $VDN_PATH/files/$HDA exist. Skip debootstrap !"
	#	return 
	#fi

	ID=$(echo $GUEST_SYS|cut -d '/' -f 1)
	VERSION_CODENAME=$(echo $GUEST_SYS|cut -d '/' -f 2)

	TMP_DIR=/tmp/bootstrap-$VERSION_CODENAME-$USER

	KVERS=$(uname -r)
	[ -n "$KVERS" ] || { error "KVERS is empty !?! "; }
	
	LOCAL_KERNEL=$(ls /boot/vmlinuz*$KVERS | head -n 1)
	
	[ -n "$LOCAL_KERNEL" ] || { error "No kernel found in /boot for $KVERS"; }
	
	LOCAL_INITRD=$(ls /boot/initrd*$KVERS | head -n 1)
	
	[ -n "$LOCAL_INITRD" ] || { error "No initrd found in /boot for $KVERS"; }
	
	FORMAT=$(file $LOCAL_INITRD)
	case "$FORMAT" in
	    *gzip*) FORMAT=gzip;;
	    *cpio*) FORMAT=asciiCpio;;
	    *Zstandard*) FORMAT=zStandard;;
	    *)  echo "Unknown initrd format ($FORMAT)" >&2
	        exit 1
	esac
	
	if [ $FORMAT = zStandard ]; then
	    [ -z "$(which zstdcat)" ] && error "zstdcat not found ! Need zstd package !" 
	    [ -z "$(which zstd)" ] && error "zstd not found ! Need zstd package !" 
	fi
	
	[ ! -d $TMP_DIR/initrd ] && mkdir -p $TMP_DIR/initrd

	export DST=$TMP_DIR/initrd

	(
		set -eu

		cd $TMP_DIR
	
		if [ ! -e $TMP_DIR/initrd/init ]; then
			echo "Extract $LOCAL_INITRD..."
			case $FORMAT in
				asciiCpio|gzip) ( cd initrd && zcat $LOCAL_INITRD | cpio -idm > /dev/null);;
				zStandard) ( cd initrd && zstdcat $LOCAL_INITRD | cpio -idm > /dev/null )
			esac
		fi
	
		[ -e $TMP_DIR/initrd/init.bak ] || cp $TMP_DIR/initrd/init $TMP_DIR/initrd/init.bak
	
		
		#rm -f $DST/bin/busybox $DST/usr/bin/busybox

		echo "Inject packages..."

		#apt-get download haveged
		#dpkg -x haveged*.deb initrd

		#apt-get download libhavege2
		#dpkg -x libhavege2*.deb initrd

		apt-get download busybox
		dpkg -x busybox_*.deb initrd

		apt-get download debootstrap
		dpkg -x debootstrap*.deb initrd

		apt-get download file
		dpkg -x file*.deb initrd

		apt-get download libmagic-mgc
		dpkg -x libmagic-mgc*.deb initrd

		#apt-get download haveged
		#dpkg -x haveged*.deb initrd


		echo "Inject files and program with depends..."
	
		[ ! -d $DST/bin ] && mkdir $DST/bin
	
		injectCommandWithDepends /bin/bash
		injectCommandWithDepends /sbin/modprobe
		injectCommandWithDepends /sbin/fdisk
		injectCommandWithDepends /sbin/mke2fs
		injectCommandWithDepends /usr/bin/gpgv
		injectCommandWithDepends /usr/bin/perl
	
		#injectCommandWithDepends /usr/bin/file
		#injectCommandWithDepends /usr/bin/ldd
		#injectCommandWithDepends /usr/bin/strace
		#injectCommandWithDepends /usr/bin/script
	
		injectFileAndLink /lib/x86_64-linux-gnu/libresolv.so.2
		injectFileAndLink /lib/x86_64-linux-gnu/libnss_files.so.2
		injectFileAndLink /lib/x86_64-linux-gnu/libnss_dns.so.2
		#injectFileAndLink /usr/lib/x86_64-linux-gnu/libidn2.so
	
		cp /sbin/mke2fs $DST/bin/mke2fs
		#injectCommandWithDepends /bin/grep
		#mv $DST/usr/bin/grep $DST/bin/grep
	
		#injectCommandWithDepends /usr/bin/perl
		#injectCommandWithDepends /usr/bin/wget
		#cp /usr/bin/wget $DST/bin
	
		mkdir -p $DST/usr/share/keyrings
		cp /usr/share/keyrings/debian-archive-keyring.gpg $DST/usr/share/keyrings
	
		cp /etc/resolv.conf $DST/etc/resolv.conf
	)

	echo "Inject scripts..."

	cp $VDN_PATH/scripts/on-boot $TMP_DIR/initrd

	set +u

	cat << EOF > $TMP_DIR/initrd/init
#!/bin/bash

#set -a
#. /config
#set +a

[ -d /dev ] || mkdir -m 0755 /dev
[ -d /proc ] || mkdir /proc
[ -d /sys ] || mkdir /sys

mkdir -p /var/lock
mount -t sysfs -o nodev,noexec,nosuid sysfs /sys
mount -t proc -o nodev,noexec,nosuid proc /proc

mkdir /dev/pts
mount -t devpts -o noexec,nosuid,gid=5,mode=0620 devpts /dev/pts

modprobe virtio_pci
modprobe virtio_blk
modprobe ext4
modprobe crc32c

modprobe virtio-net

mdev -s

rm -f /dev/null; mknod -m 666 /dev/null c 1 3

if ! fdisk -l /dev/vda | grep -q /dev/vda1; then
    echo -e "n\np\n1\n\n\nw\n" | fdisk /dev/vda
    mdev -s
    /bin/mke2fs -j -t ext4 /dev/vda1
fi

rm -f /dev/null; mknod -m 666 /dev/null c 1 3

mkdir -p /tmp/d
mount /dev/vda1 /tmp/d || {
    echo "Can't mount partition !" >&2
    echo "Repair + exit to continue or poweroff -f to halt !"
    /bin/busybox ash
}

ifconfig eth0 10.0.2.15
route add default gw 10.0.2.2

ln -sf /bin/bash /bin/sh

[ -n "$http_proxy" ] && export http_proxy="$http_proxy"
[ -n "$https_proxy" ] && export https_proxy="$https_proxy"

#echo "Before debootstrap. exit to continue."
#/bin/sh -i

if [ ! -d /tmp/d/bin ]; then
    echo "Debootstrap $VERSION_CODENAME ..."
    debootstrap --arch=amd64  $VERSION_CODENAME /tmp/d
fi

mount -o bind /dev /tmp/d/dev
mount -t devpts -o noexec,nosuid,gid=5,mode=0620 devpts /tmp/d/dev/pts
mount -o bind /proc /tmp/d/proc
mount -o bind /sys /tmp/d/sys

#cp /config /tmp/d/root/config
cp /base.sh /tmp/d/root/base.sh

[ ! -d /tmp/d/etc/vdn ] && mkdir -p /tmp/d/etc/vdn
cp /on-boot /tmp/d/etc/vdn
chmod 755 /tmp/d/etc/vdn/on-boot

#echo "Before chroot, exit to quit"
#/bin/busybox ash

chroot /tmp/d /root/base.sh

#echo "In chroot exit to quit"
#chroot /tmp/d /bin/bash

#/bin/busybox ash

poweroff -f

EOF

	chmod 755 $TMP_DIR/initrd/init

	cat << EOF > $DST/base.sh

#set -a
#. /root/config
#set +a

export DEBIAN_FRONTEND=noninteractive

[ -n "$http_proxy" ] && export http_proxy="$http_proxy"
[ -n "$https_proxy" ] && export https_proxy="$https_proxy"

apt-get -y update
apt-get -y upgrade

apt-get -y install linux-image-amd64 grub2 

# Inject initramfs config scripts

[ ! -d /etc/initramfs-tools ] && mkdir -p /etc/initramfs-tools

echo "overlay" >> /etc/initramfs-tools/modules
sed -i -re 's/^MODULES=.*$/MODULES=dep/' /etc/initramfs-tools/initramfs.conf

update-initramfs -u
update-grub

rm -f /etc/initramfs-tools/scripts/init-premount/vdn
cat << END > /etc/initramfs-tools/scripts/local-bottom/vdn
#!/bin/sh

PREREQ="lvm"
prereqs()
{
	echo "\\\$PREREQ"
}

case \\\$1 in
	prereqs)
              prereqs
              exit 0
              ;;
esac

. /scripts/functions
# Begin real processing below this line

echo "ECHO : Starting vdn pre-mount, exit to quit !" >&2
log_begin_msg "Starting vdn pre-mount, exit to quit !"

# Extract tgz

lastDisk=\\\$(ls /dev/vd*| grep '/...$' | tail -n 1)

if [ -n "\\\$lastDisk" ]; then
    if tar -C / -xzf \\\$lastDisk; then
	set -a
	. /etc/vdn/config
	set +a
    else
        echo >&2
        echo "WARNING : no vdn config partition found !" >&2
        sleep 3
	exit 1
    fi
else
   echo 'Not a VDN VM (/dev/vd? !)' >&2
   sleep 3
   exit 1
fi

#echo "/etc/initramfs-tools/scripts/local-bottom/vdn : before . /etc/vdn/on-initramfs" >&2
#/bin/busybox ash

chown root:root /
chmod 755 /

. /etc/vdn/on-initramfs 

log_end_msg

END

chmod 755 /etc/initramfs-tools/scripts/local-bottom/vdn

#echo "base.sh : after install kernel"
#/bin/bash -i

[ -n "$http_proxy" ] && export http_proxy="$http_proxy"
[ -n "$https_proxy" ] && export https_proxy="$https_proxy"

apt-get -y update
apt-get -y upgrade

apt-get -y install ssh locales mingetty file

#grub-install /dev/vda
#update-grub

echo "root:$(getRandomPasswd)" | chpasswd

[ ! -e /home/test ] && adduser --disabled-password --gecos '' test
echo "test:$(getRandomPasswd)" | chpasswd

apt-get -y install ssh # task-ssh-server
#apt-get -y install task-xfce-desktop

cat << END > /etc/fstab
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
# / was on /dev/vda1 during installation
/dev/vda1 /               ext4    errors=remount-ro 0       1
END

[ ! -d /etc/vdn ] && mkdir /etc/vdn

if [ ! -e /etc/rc.local ]; then
	cat << END > /etc/rc.local
#!/bin/sh -e
#
# rc.local
#
# This script is executed at the end of each multiuser runlevel.
# Make sure that the script will "exit 0" on success or any other
# value on error.
#
# In order to enable or disable this script just change the execution
# bits.

END
fi

if ! grep -q /etc/vdn/on-boot /etc/rc.local; then
	cat << END >> /etc/rc.local
sh /etc/vdn/on-boot
END
fi

chmod 755 /etc/rc.local

echo "Allow root autologin on ttyS0"
sed -i -re 's,^ExecStart=.*$,ExecStart=-/sbin/mingetty --noclear --autologin root %I,' /lib/systemd/system/serial-getty@.service

echo "Allow net.ifnames=0 in GRUB + console"
sed -i -re 's,^GRUB_CMDLINE_LINUX_DEFAULT=.*$,GRUB_CMDLINE_LINUX_DEFAULT=\"net.ifnames=0 console=ttyS0\,115200n8 noresume blacklist=floppy\",' /etc/default/grub
echo "Set 1s timout for Grub menu"
sed -i -re 's,^GRUB_TIMEOUT=.*$,GRUB_TIMEOUT=0,' /etc/default/grub
update-grub

echo "Allow ssh root connection"
if grep -q '^#?PermitRootLogin ' /etc/ssh/sshd_config; then
    sed -i -re 's/^#?PermitRootLogin/PermitRootLogin prohibit-password' /etc/ssh/sshd_config
else
    echo 'PermitRootLogin prohibit-password' >> /etc/ssh/sshd_config
fi

#apt-get install -y --reinstall linux-image-amd64
update-initramfs -u
grub-install /dev/vda
#update-grub

#echo "End of base.sh, exit to quit"
#/bin/bash -i

EOF

	chmod 755 $DST/base.sh

	[ ! -e $VDN_PATH/files/$HDA ] && {
		echo "Create sparse disk $VDN_PATH/files/$HDA ($HDA_SIZE M)..."
		dd of=$VDN_PATH/files/$HDA count=0 bs=1M seek=$HDA_SIZE
	}

	# Build $TMP_DIR/initrd.img

	#if [ ! -e $TMP_DIR/initrd.img ]; then
		echo "Create $TMP_DIR/initrd.img..."
		case $FORMAT in
			asciiCpio|gzip) ( cd $TMP_DIR/initrd && find . | cpio -o -H newc -R root:root | gzip -9 > $TMP_DIR/initrd.img);;
			zStandard) ( cd $TMP_DIR/initrd && find . | cpio -o -H newc -R root:root | zstd -9 > $TMP_DIR/initrd.img );;
		esac
	#fi

	#echo "Press return to continue !"
	#read

	echo "Boot and debootstrap..."	

	qemu-system-x86_64 -kernel $LOCAL_KERNEL -smp 8 -enable-kvm -cpu host -device virtio-rng-pci,rng=rng0 -object rng-random,filename=/dev/urandom,id=rng0 -rtc base=localtime -m 3072M -nographic -serial mon:stdio -monitor null -initrd $TMP_DIR/initrd.img -append "root=/dev/vda boot=live ro console=ttyS0,115200n8 net.ifnames=0 noresume" -boot order=c -drive file=$VDN_PATH/files/$HDA,if=virtio,format=raw -device virtio-net-pci,netdev=n0,mac=52:56:0A:E8:00:02 -netdev user,id=n0

}

# $1 : system name started
cleanHistory() {
	echo "Clear /var/log, history, ..."
	vdn-ssh -t root@$1 '

	#rm -Rf /etc/vdn
	set -a
        . /etc/vdn/config
        set +a

	rm -f /etc/vdn-$MODE-initialized

	#for i in $(find /var/log -type f); do cat /dev/null > $i; done
	find /var/log -name "*.gz" -delete

	echo "Clear .bash_history"

	rm -f /root/.bash_history
	touch /root/.bash_history
	chmod 600 /root/.bash_history
	rm -f /home/test/.bash_history
	touch /home/test/.bash_history
	chmod 600 /home/test/.bash_history

	echo "Clear .cache .mozilla"
	for d in /root /home/test; do
        	rm -Rf $d/.cache
        	rm -Rf $d/.mozilla
	done

        echo "$$$ Clear apt-cache..."
        apt autoremove -y
        sleep 1
        apt-get clean


	echo "Clear authorized_keys (only user test)"

	for d in /root /home/test; do 
        	rm -f $d/.ssh/authorized_keys
	        rm -Rf $d/.mozilla
	done

	echo end of cleaning !

	echo "poweroff (in 3 s) !"
	poweroff -f

'
}