#!/bin/bash
set -euo pipefail

fail() {
    printf 'Genesis export: %s\n' "$*" >&2
    exit 1
}

if (($# != 3)); then
    printf '%s\n' 'Usage: export ARCHITECTURE DEPLOY_DIRECTORY OUTPUT_DIRECTORY' >&2
    exit 2
fi

architecture=$1
deploy_dir=${2%/}
output_dir=${3%/}

case "$architecture" in
    x86) kernel_name=bzImage ;;
    x86_64) kernel_name=bzImage ;;
    ppc64) kernel_name=vmlinux ;;
    ppc64le) kernel_name=vmlinux ;;
    armv7hf) kernel_name=zImage ;;
    aarch64) kernel_name=Image ;;
    riscv64) kernel_name=Image ;;
    *) fail "unsupported architecture: $architecture" ;;
esac

[[ -d $deploy_dir && ! -L $deploy_dir ]] \
    || fail "invalid deploy directory: $deploy_dir"
[[ ! -e $output_dir && ! -L $output_dir ]] \
    || fail "output already exists: $output_dir"

machine=xcat-genesis-${architecture//_/-}
machine_dir=$deploy_dir/images/$machine
image_name=xcat-genesis-image-$machine.rootfs
license_machine=${machine//-/_}

resolve_artifact() {
    local path=$1 resolved

    resolved=$(readlink -f -- "$path")
    [[ -f $resolved && ! -L $resolved ]] || fail "missing artifact: $path"
    printf '%s\n' "$resolved"
}

kernel=$(resolve_artifact "$machine_dir/$kernel_name")
initramfs=$(resolve_artifact "$machine_dir/$image_name.cpio.gz")
package_manifest=$(resolve_artifact "$machine_dir/$image_name.manifest")
spdx=$(resolve_artifact "$machine_dir/$image_name.spdx.json")
vex=$(resolve_artifact "$machine_dir/$image_name.vex.json")
license_dir=$(basename "${package_manifest%.manifest}")
license_manifest=$(resolve_artifact \
    "$deploy_dir/licenses/$license_machine/$license_dir/license.manifest")

parent=$(dirname -- "$output_dir")
name=$(basename -- "$output_dir")
install -d -m 0755 "$parent"
staging=$(mktemp -d "$parent/.${name}.XXXXXX")
trap 'rm -rf -- "$staging"' EXIT

install -m 0644 "$kernel" "$staging/kernel"
install -m 0644 "$initramfs" "$staging/initramfs.cpio.gz"
install -m 0644 "$package_manifest" "$staging/image.manifest"
install -m 0644 "$spdx" "$staging/image.spdx.json"
install -m 0644 "$vex" "$staging/image.vex.json"
install -m 0644 "$license_manifest" "$staging/license.manifest"
printf 'format=xcat-genesis\nversion=1\narchitecture=%s\n' "$architecture" \
    >"$staging/xcat-genesis.manifest"
chmod 0644 "$staging/xcat-genesis.manifest"

if [[ $architecture == riscv64 ]]; then
    firmware=$(resolve_artifact "$machine_dir/fw_jump.elf")
    install -m 0644 "$firmware" "$staging/fw_jump.elf"
fi

(
    cd "$staging"
    sha256sum -- * >SHA256SUMS
    sha256sum -c SHA256SUMS >/dev/null
)

mv -- "$staging" "$output_dir"
trap - EXIT
printf 'Exported Genesis %s to %s\n' "$architecture" "$output_dir"