#
# Use qemu to host dockerimages.
#
# TODO: Write helpers to pull/convert docker image to qcow2
# TODO: Impl host shared dirs. Should be possible using 9pfs (see link).
#
# for "virt-make-fs" install "guestfs-tools".
#
# Some Links:
# - [Execute Docker Containers as QEMU MicroVMs](https://mergeboard.com/blog/2-qemu-microvm-docker/)
#

true \
  && LINUX_URL=https://cdn.kernel.org/pub/linux/kernel/v6.x/linux-6.7.4.tar.xz \
  && SUDO=sudo \
  && CACHEDIR=/var/tmp \
  && WORKDIR=/home/$USER/work \
  && LINUX_TXZ=$(basename "${LINUX_URL:?}") \
  && $SUDO apt install -y --no-install-recommends curl make gcc bc flex bison libc-dev libelf-dev libssl-dev \
  && cd "${CACHEDIR:?}" \
  && curl -L "${LINUX_URL:?}" -O \
  && mkdir -p "${WORKDIR:?}" \
  && cd "${WORKDIR:?}" \
  && tar xf "${CACHEDIR:?}/${LINUX_TXZ:?}" \
  && cd linux* \
  && base64 -d <<EOF | gunzip > .config &&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EOF
true \
  && make olddefconfig \
  && make -j$(nproc) \
  && `# Create our own pseudo 'init' system` \
  && `# TODO fix zombie processes (aka add waitpid() SIGCHILD handling to init)` \
  && mkdir "${WORKDIR:?}/myinit" \
  && cd "${WORKDIR:?}/myinit" \
  && base64 -d <<EOF | gunzip > "./myinit.c" &&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EOF
true \
  && CFLAGS="-Wall -Werror -pedantic -static" `# TODO maybe add "-Os -s"` \
  && gcc -o myinit myinit.c ${CFLAGS?}\
  && echo "[ERROR] TODO Need more steps here" && false \
  && echo _script_is_DONE_kx1n2kgNWRdpBYTP_ \





## Test launch pure kernel (kernel panic expected)

qemu-system-x86_64 \
    -M microvm,x-option-roms=off,isa-serial=off,rtc=off -no-acpi -cpu host \
    -accel kvm -nodefaults -no-user-config -nographic -no-reboot \
    -device virtio-serial-device \
    -chardev stdio,id=virtiocon0 -device virtconsole,chardev=virtiocon0 \
    -kernel kernel/bzImage -append "console=hvc0 acpi=off reboot=t panic=-1" \
    ;


## Test launch full VM

KERNEL="${WORKDIR:?}/linux-*/arch/x86_64/boot/bzImage"
HOST_SHARE_DIR="/path/to/host/share"
QEMU_IMAGE="dockerimage.qcow2"
# mount share from guest:  mount -t 9p myMountTag /mnt/share -otrans=virtio,version=9p2000.L,msize=52428800
qemu-system-x86_64 \
    -M microvm,x-option-roms=off,isa-serial=off,rtc=off -no-acpi -no-reboot \
    -accel kvm -cpu host -nodefaults -no-user-config -nographic \
    -m 1G -smp $(nproc) \
    -device virtio-serial-device \
    -chardev stdio,id=virtiocon0 -device virtconsole,chardev=virtiocon0 \
    -kernel "${KERNEL:?}" \
    -append "console=hvc0 root=/dev/vda rw acpi=off reboot=t panic=-1 quiet" \
    -drive id=root,file=${QEMU_IMAGE:?},format=qcow2,if=none \
    -device virtio-blk-device,drive=root \
    -netdev user,id=mynet0,hostfwd=tcp:127.0.0.1:8080-10.0.2.15:80 \
    -device virtio-net-device,netdev=mynet0 \
    -fsdev local,path=${HOST_SHARE_DIR:?},security_model=none,id=www,readonly=on \
    -device virtio-9p-device,fsdev=www,mount_tag=myMountTag \
    -device virtio-rng-device
    ;


## Example docker image transformation

  && rm -rf "${WORKDIR:?}/dockerbuild" \
  && mkdir "${WORKDIR:?}/dockerbuild" \
  && cd "${WORKDIR:?}/dockerbuild" \
  && cp "${WORKDIR:?}/myinit/myinit" init \
  && base64 -d <<EOF | gzip -d > "Dockerfile" &&
H4sIAMsc+GYAA3ML8vdVyEvPzKuwMtQzMtQz4AoK9VNILChRKC1ISSxJhXMz84pLEnNyFHQrFTKL
k3VTMpILdJNzMlPzSsBKinIVdNMU9IuTMvP0M/MyS7ic/QMiFUAsZEEAfPYPR24AAAA=
EOF
true \
  && DOCKER_BUILDKIT=1 docker build -f ./Dockerfile --output "type=tar,dest=dockerimage.tar" . \
  && virt-make-fs --format=qcow2 --size=+200M dockerimage.tar dockerimage-large.qcow2 \
  && qemu-img convert dockerimage-large.qcow2 -O qcow2 dockerimage.qcow2 \
  && rm dockerimage-large.qcow2 \