#!/usr/bin/bash
set -euo pipefail

inspect-manifest() {
    local _image
    _image="${1?"image is required"}"

    local _temp_dir
    _temp_dir="${TMPDIR-/tmp}"
    local _image_hash
    _image_hash="$(echo -n "$_image" | shasum | cut -f1 -d' ')"
    local _temp_file
    _temp_file="${_temp_dir}/check-docker-image-${_image_hash}.json"

    if [ ! -f "$_temp_file" ]; then
        docker buildx imagetools inspect \
            --format='{{json .}}' \
            "$_image" >"$_temp_file"
    fi

    cat "$_temp_file"
}

check-image() {
    local _image
    _image="${1?"image is required"}"

    echo "checking image=$_image"

    local _manifest
    _manifest="$(inspect-manifest "$_image")"

    local _has_arm64
    _has_arm64="$(echo "$_manifest" | jq '
        .manifest.manifests
        | map(select(.platform.architecture == "arm64" and .platform.os == "linux"))
        | length >= 1
    ')"

    if [[ "$_has_arm64" != "true" ]]; then
        echo "- missing ARM64 in $_manifest"
        exit 1
    fi

    local _has_amd64
    _has_amd64="$(echo "$_manifest" | jq '
        .manifest.manifests
        | map(select(.platform.architecture == "amd64" and .platform.os == "linux"))
        | length >= 1
    ')"

    if [[ "$_has_amd64" != "true" ]]; then
        echo "- missing AMD64 in $_manifest"
        exit 1
    fi
}

check-dockerfile() {
    local _file
    _file="${1?"file is required"}"

    echo "checking dockerfile=$_file"

    while IFS= read -r _image; do
        check-image "$_image"
    done < <(sed -n -r -e 's/^FROM ([^:]*)(:[^@]*)(@sha256[^ ]*).*$/\1\2\3/p' "$_file")
}

check-directory() {
    local _directory
    _directory="${1?"directory is required"}"

    echo "checking directory=$_directory"

    local _file
    while IFS= read -r -d '' _file; do
        check-dockerfile "$_file"
    done < <(find "$_directory" -name "*Dockerfile*" -print0)
}

main() {
    local _project_root
    _project_root="$(cd "$(dirname "${BASH_SOURCE[0]}")" >/dev/null 2>&1 && pwd)/.."

    check-directory "$_project_root"
}

main