FROM stagex/busybox AS busybox
FROM stagex/musl AS musl
FROM stagex/xorriso AS xorriso
FROM stagex/syslinux AS syslinux
FROM stagex/cpio AS cpio
FROM stagex/linux-airgap AS linux
FROM stagex/mtools AS mtools
FROM stagex/dosfstools AS dosfstools

FROM scratch AS base
COPY --from=busybox . /
COPY --from=musl . /
COPY --from=xorriso . /
COPY --from=cpio . /
COPY --from=mtools . /
COPY --from=linux . /
COPY --from=dosfstools . /
COPY --from=syslinux . /

FROM base AS build
COPY --from=linux /bzImage /iso/boot/bzImage
COPY --from=stagex/busybox . initramfs
COPY --chmod=0755 <<-EOF initramfs/init
    #!/bin/sh
    /bin/sh
EOF
RUN cd initramfs && find . | cpio -o -H newc | gzip -9 > /iso/boot/init.gz
COPY <<-EOF iso/isolinux/isolinux.cfg
    DEFAULT linux
    LABEL linux
    KERNEL boot/bzImage
    APPEND initrd=boot/init.gz
EOF
COPY --from=syslinux /usr/share/syslinux/isolinux.bin iso/isolinux/
COPY --from=syslinux /usr/share/syslinux/ldlinux.c32 iso/isolinux/
RUN <<-EOF
    set -eux
    mkdir -p iso/efi
    truncate -s $((10796+128+128))k iso/efi/esp.img
    mkfs.fat -F 16 -f 1 -M 0xF0 -r 112 -R 1 iso/efi/esp.img
    mmd -i iso/efi/esp.img ::boot
    mcopy -i iso/efi/esp.img iso/boot/bzImage ::boot/bzImage
    mcopy -i iso/efi/esp.img iso/boot/init.gz ::boot/init.gz
    mmd -i iso/efi/esp.img ::syslinux
    mcopy -i iso/efi/esp.img iso/isolinux/isolinux.cfg ::syslinux/syslinux.cfg
    mcopy -i iso/efi/esp.img /usr/share/syslinux/efi64/ldlinux.e64 ::syslinux/ldlinux.e64
    mmd -i iso/efi/esp.img ::efi
    mmd -i iso/efi/esp.img ::efi/boot
    mcopy -i iso/efi/esp.img /usr/share/syslinux/efi64/syslinux.efi ::efi/boot/boot64.efi
    ls -Rlah iso
EOF
FROM build AS install
RUN xorriso \
    -as mkisofs \
    -output airgap.iso \
    -eltorito-boot isolinux/isolinux.bin \
    -no-emul-boot \
    -boot-load-size 4 \
    -boot-info-table \
    -eltorito-alt-boot \
    -eltorito-platform efi \
    -eltorito-boot efi/esp.img \
    -no-emul-boot \
    -eltorito-catalog isolinux/boot.cat \
   iso
#RUN isohybrid airgap.iso

FROM scratch AS package
COPY --from=install /airgap.iso /