#!/bin/bash
# we depend on a properly build rootfs
if [ "$EUID" -ne 0 ]
then echo "Please run as root"
    exit
fi

if [ ! -d rootfs\ overrides/core/node_modules ]
then
    echo "please run npmi.sh"
    exit 1
fi

CHIBRAX_MOUNT_POINT="/tmp/core"
EFI_MOUNT_POINT="/tmp/efi"

rm -f disk.img

while umount -R rootfs/proc
do
    echo ""
done

#create a 8Gb iso
dd if=/dev/zero of=disk.img bs=1024k seek=$((1000 * 8)) count=0

HEADER_SIZE=2048
EFI_SIZE=512
EFI_SECTOR_LIMIT=997376
ROOT_SECTOR_LIMIT=15382528
SECTOR_SIZE=512
HEADER_OFFSET=$(($HEADER_SIZE * $SECTOR_SIZE))
ROOT_OFFSET=$(( ($EFI_SECTOR_LIMIT + $HEADER_SIZE ) * $SECTOR_SIZE ))

#creating a msdos image for mbr boot
parted disk.img mklabel gpt
echo "parted disk.img mkpart ext4 0% ${EFI_SIZE}M"
parted disk.img mkpart efi 0% ${EFI_SIZE}MB
parted disk.img mkpart root ${EFI_SIZE}MB 100%

##EFI
#parted disk.img name 1 root
START_SECTOR=$(file disk.img | cut -d',' -f 8 | cut -d' ' -f3)
echo "Start sector :" $START_SECTOR

losetup --offset $HEADER_OFFSET -f disk.img
EFI_LOOP=$(losetup -a | grep -v deleted | grep disk.img | grep $HEADER_OFFSET | cut -d':' -f 1)
mkfs.fat -F 32 ${EFI_LOOP}

echo "EFI LOOP: $EFI_LOOP"

mkdir -p $EFI_MOUNT_POINT
mount ${EFI_LOOP} $EFI_MOUNT_POINT

echo $ROOT_SECTOR_LIMIT
losetup --offset $ROOT_OFFSET -f disk.img --sizelimit $(($ROOT_SECTOR_LIMIT * 512))
ROOT_LOOP=$(losetup -a | grep -v deleted | grep disk.img | grep $ROOT_OFFSET | grep -v $EFI_LOOP | cut -d':' -f 1)
mkfs.ext4 ${ROOT_LOOP}

echo "ROOT LOOP: $ROOT_LOOP"

mkdir $CHIBRAX_MOUNT_POINT -p
mount ${ROOT_LOOP} $CHIBRAX_MOUNT_POINT

echo "coping rootfs"
cp rootfs/* $CHIBRAX_MOUNT_POINT -r
echo "done"

cp kernel/src/arch/x86/boot/bzImage $EFI_MOUNT_POINT/bzImage.efi

umount $CHIBRAX_MOUNT_POINT
umount $EFI_MOUNT_POINT
losetup -d $EFI_LOOP
losetup -d $ROOT_LOOP
#built by root but used by any, usefull to run the vm without root privileges
chmod 757 disk.img