#!/usr/bin/env bash

set -euxo pipefail

IMAGE_TYPE="${1:-ubuntu}"
PACKER_BUILD_FILE=

errmsg () {
    echo "$@" > /dev/stderr
}

preflight () {
    case "${IMAGE_TYPE}" in 
    ubuntu) PACKER_BUILD_FILE="boards/raspberry-pi-4/ubuntu_server_20.04_arm64.json" ;;
    raspbian) PACKER_BUILD_FILE="boards/raspberry-pi/raspios-lite-arm.json" ;;
    custom)
        PACKER_BUILD_FILE="${2:-}"
        if [ -z "${PACKER_BUILD_FILE}" ]
        then
            errmsg "[!] custom board requires a board file path"
            exit 1
        fi
        ;;
    *)
        errmsg "[!] invalid image type ${IMAGE_TYPE}."
        errmsg "[!] valid image types are"
        errmsg "    - raspbian"
        errmsg "    - ubuntu"
        errmsg "    - custom path/to/board/file"
        exit 1
        ;;
    esac
}

build_image () {
    cd build/packer-builder-arm
    packer build ${PACKER_BUILD_FILE}
}