#!/bin/bash

[[ -f /etc/default/grub ]] && . /etc/default/grub
[[ -f /etc/os-release ]] && . /etc/os-release

COMMAND="$1"
KERNEL_VERSION="$2"
BOOT_DIR_ABS="$3"
KERNEL_IMAGE="$4"

KERNEL_DIR="${KERNEL_IMAGE%/*}"

MACHINE_ID=$KERNEL_INSTALL_MACHINE_ID

# Remove it, since for grub2 the images are always installed in /boot
rm -rf "${BOOT_DIR_ABS%/*}"

EFIDIR="$(echo "${ID}" | sed -e 's/rhel/redhat/')"

BLS_DIR="/boot/loader/entries"
if [ -d /sys/firmware/efi ]; then
    BLS_DIR="/boot/efi/EFI/${EFIDIR}/loader/entries"
fi

mkbls() {
    local kernelver=$1 && shift
    local datetime=$1 && shift

    local debugname=""
    local flavor=""

    if [[ "$KERNEL_VERSION" == *\+* ]] ; then
        local flavor=-"${KERNEL_VERSION##*+}"
        if [[ "${flavor}" == "-debug" ]]; then
            local debugname=" with debugging"
        fi
    fi

    cat <<EOF
title ${NAME} (${kernelver}) ${VERSION}${debugname}
linux /vmlinuz-${kernelver}
initrd /initramfs-${kernelver}.img
options \$kernelopts
id ${ID}-${datetime}-${kernelver}
grub_users \$grub_users
grub_arg --unrestricted
grub_class kernel${flavor}
EOF
}

[[ "$KERNEL_VERSION" == *\+* ]] && flavor=-"${KERNEL_VERSION##*+}"
case "$COMMAND" in
    add)
        if [[ "${KERNEL_DIR}" != "/boot" ]]; then
            for i in \
                "$KERNEL_IMAGE" \
                    "$KERNEL_DIR"/System.map \
                    "$KERNEL_DIR"/config \
                    "$KERNEL_DIR"/zImage.stub \
                    "$KERNEL_DIR"/dtb
            do
                [[ -e "$i" ]] || continue
                cp -aT "$i" "/boot/${i##*/}-${KERNEL_VERSION}"
                command -v restorecon &>/dev/null && \
                    restorecon -R "/boot/${i##*/}-${KERNEL_VERSION}"
            done
            # hmac is .vmlinuz-<version>.hmac so needs a special treatment
            i="$KERNEL_DIR/.${KERNEL_IMAGE##*/}.hmac"
            if [[ -e "$i" ]]; then
                cp -a "$i" "/boot/.${KERNEL_IMAGE##*/}-${KERNEL_VERSION}.hmac"
                command -v restorecon &>/dev/null && \
                    restorecon "/boot/.${KERNEL_IMAGE##*/}-${KERNEL_VERSION}.hmac"
            fi
        fi

        if [[ "x${GRUB_ENABLE_BLSCFG}" = "xtrue" ]] || [[ ! -f /sbin/new-kernel-pkg ]]; then
            [[ -d "$BLS_DIR" ]] || mkdir -m 0700 -p "$BLS_DIR"
            BLS_TARGET="${BLS_DIR}/${MACHINE_ID}-${KERNEL_VERSION}.conf"
            if [[ -f "${KERNEL_DIR}/bls.conf" ]]; then
                cp -aT "${KERNEL_DIR}/bls.conf" "${BLS_TARGET}" || exit $?
            else
                mkbls "${KERNEL_VERSION}" \
                    "$(date -u +%Y%m%d%H%M%S -d "$(stat -c '%y' "${KERNEL_DIR}")")" \
                    >"${BLS_TARGET}"
            fi
            exit 0
        fi

        /sbin/new-kernel-pkg --package "kernel${flavor}" --install "$KERNEL_VERSION" || exit $?
        /sbin/new-kernel-pkg --package "kernel${flavor}" --mkinitrd --dracut --depmod --update "$KERNEL_VERSION" || exit $?
        /sbin/new-kernel-pkg --package "kernel${flavor}" --rpmposttrans "$KERNEL_VERSION" || exit $?
        # If grubby is used there's no need to run other installation plugins
        exit 77
        ;;
    remove)

        if [[ "x${GRUB_ENABLE_BLSCFG}" = "xtrue" ]] || [[ ! -f /sbin/new-kernel-pkg ]]; then
            rm -f "${BLS_DIR}/${MACHINE_ID}-${KERNEL_VERSION}.conf"

            for i in vmlinuz System.map config zImage.stub dtb; do
                rm -rf "/boot/${i}-${KERNEL_VERSION}"
            done
            # hmac is .vmlinuz-<version>.hmac so needs a special treatment
            rm -f "/boot/.vmlinuz-${KERNEL_VERSION}.hmac"

            exit 0
        fi

        /sbin/new-kernel-pkg --package "kernel${flavor+-$flavor}" --rminitrd --rmmoddep --remove "$KERNEL_VERSION" || exit $?
        # If grubby is used there's no need to run other installation plugins
        exit 77
        ;;
    *)
        ;;
esac