#!/bin/bash
# build-sbo-testbuild.sh — sbo-testbuild:{ver} FROM sbo-full:{ver}.
# Adds sbopkg + sbo-maintainer-tools from prebuilt .txz in PKGDIR.
# Rebuilds when the full image OR the .txz set changes.
set -euo pipefail
HERE="$(cd "$(dirname "$0")" && pwd)"
source "${HERE}/config"
LOG_TAG=testbuild
source "${HERE}/lib.sh"

FULL_IMAGE="${REGISTRY}/sbo-full"
TB_IMAGE="${REGISTRY}/sbo-testbuild"
DIGEST_LABEL="sbo.testbuild.full-digest"
PKGS_LABEL="sbo.testbuild.pkgs-hash"

FORCE=false
OPT_VERSION=""
while [[ $# -gt 0 ]]; do
    case "$1" in
        --version) OPT_VERSION="$2"; shift 2 ;;
        --force)   FORCE=true;       shift   ;;
        *) _err "unknown argument: $1" ;;
    esac
done
if [[ -n "${OPT_VERSION}" ]]; then
    BUILD_VARIANTS=("${OPT_VERSION}")
else
    BUILD_VARIANTS=("${VARIANTS[@]}")
fi

# Verify the required .txz are present before doing anything.
require_pkgs() {
    [[ -d "${PKGDIR}" ]] || _err "PKGDIR missing: ${PKGDIR}"
    compgen -G "${PKGDIR}/sbopkg-*.txz" >/dev/null \
        || _err "no sbopkg-*.txz in ${PKGDIR}"
    compgen -G "${PKGDIR}/sbo-maintainer-tools-*.txz" >/dev/null \
        || _err "no sbo-maintainer-tools-*.txz in ${PKGDIR}"
}

# needs_rebuild FULL_TAG TB_TAG PKGS_HASH -> 0 if rebuild needed
needs_rebuild() {
    local full_tag="$1" tb_tag="$2" pkgs_hash="$3"
    [[ "${FORCE}" == "true" ]] && { _log "  --force."; return 0; }

    local full_digest
    full_digest=$(docker inspect --format '{{index .RepoDigests 0}}' \
        "${full_tag}" 2>/dev/null || echo "")
    [[ -n "${full_digest}" ]] || { _warn "  no full digest; rebuilding."; return 0; }

    local rec_digest rec_pkgs
    rec_digest=$(docker inspect \
        --format "{{index .Config.Labels \"${DIGEST_LABEL}\"}}" \
        "${tb_tag}" 2>/dev/null || echo "")
    rec_pkgs=$(docker inspect \
        --format "{{index .Config.Labels \"${PKGS_LABEL}\"}}" \
        "${tb_tag}" 2>/dev/null || echo "")

    if [[ "${full_digest}" == "${rec_digest}" && "${pkgs_hash}" == "${rec_pkgs}" ]]; then
        _log "  full image and .txz set unchanged; skipping."
        return 1
    fi
    _log "  full image or .txz set changed; rebuilding."
    return 0
}

build_variant() {
    local VERSION="$1"
    local FULL_TAG="${FULL_IMAGE}:${VERSION}"
    local TB_TAG="${TB_IMAGE}:${VERSION}"
    _log "=== ${TB_TAG} ==="

    _log "  Pulling ${FULL_TAG}..."
    docker pull "${FULL_TAG}"

    local PKGS_HASH; PKGS_HASH="$(txz_hash "${PKGDIR}")"

    if ! needs_rebuild "${FULL_TAG}" "${TB_TAG}" "${PKGS_HASH}"; then
        return 0
    fi

    local FULL_DIGEST
    FULL_DIGEST=$(docker inspect --format '{{index .RepoDigests 0}}' "${FULL_TAG}")

    local WORKDIR; WORKDIR="$(mktemp -d /tmp/sbo-testbuild.XXXXXX)"
    # shellcheck disable=SC2064
    trap "rm -rf '${WORKDIR}'" EXIT
    mkdir -p "${WORKDIR}/pkgs"
    cp "${PKGDIR}"/sbopkg-*.txz "${PKGDIR}"/sbo-maintainer-tools-*.txz "${WORKDIR}/pkgs/"

    cat > "${WORKDIR}/Dockerfile" <<DOCKERFILE
FROM ${FULL_TAG}
LABEL maintainer="danix <danix@danix.xyz>"
COPY pkgs/*.txz /tmp/pkgs/
RUN installpkg /tmp/pkgs/*.txz && rm -rf /tmp/pkgs
RUN /sbin/ldconfig
LABEL org.opencontainers.image.created="$(date -u +%Y-%m-%dT%H:%M:%SZ)"
LABEL org.opencontainers.image.title="SBo test-build env ${VERSION} (x86_64)"
LABEL org.opencontainers.image.description="Slackware ${VERSION} full + sbopkg + sbo-maintainer-tools"
LABEL slackware.version="${VERSION}"
LABEL ${DIGEST_LABEL}="${FULL_DIGEST}"
LABEL ${PKGS_LABEL}="${PKGS_HASH}"
CMD ["/bin/bash"]
DOCKERFILE

    local BUILD_FLAGS=()
    [[ "${FORCE}" == "true" ]] && BUILD_FLAGS+=(--no-cache)
    _log "  Building ${TB_TAG}..."
    docker build "${BUILD_FLAGS[@]}" -t "${TB_TAG}" "${WORKDIR}"
    _log "  Pushing ${TB_TAG}..."
    docker push "${TB_TAG}"
    _log "=== Done: ${TB_TAG} ==="
}

require_pkgs
for VERSION in "${BUILD_VARIANTS[@]}"; do
    build_variant "${VERSION}"
done