#!/bin/bash


function download_and_verify_ipxe()
{
    local ipxe_path="$1"
    local ipxeshasum1='a'
    local ipxeshasum2='b'

    which wget && which jq && which curl || /bin/false
    if [ $? -ne 0 ]; then
        apt update -yq && apt -yq install wget jq curl
    fi

    # This gets the info for the most current release, in JSON format
    release_info=$(curl "https://git.bitmessage.org/api/v1/repos/maxweiss/ipxe_scripts/releases?per_page=1&page=1&limit=1")

    lkrn_url=$(echo ${release_info} | jq '.[0].assets[] | select(.name=="ipxe.lkrn")' | jq -r .browser_download_url | tr -d '\n')
    shasums_url=$(echo ${release_info} | jq '.[0].assets[] | select(.name=="SHA256SUMS")' | jq -r .browser_download_url | tr -d '\n')

    if [[ -z $lkrn_url ]] || [[ $lkrn_url = *[^[:space:]]* ]]; then
        echo "download failed" > "$ipxe_path"
    else
        wget "${lkrn_url}" -O "$ipxe_path" || echo "download failed" > "$ipxe_path"
    fi
    if [[ -z $shasums_url ]] || [[ $shasums_url = *[^[:space:]]* ]]; then
        echo "z ipxe.lkrn" > "${ipxe_path}.sha256sums"
    else
        wget "${shasums_url}" -O "${ipxe_path}.sha256sums" || echo "z ipxe.lkrn" > "${ipxe_path}.sha256sums"
    fi

    ipxeshasum1=$(cat "${ipxe_path}.sha256sums" | grep "ipxe.lkrn" | awk '{print $1}' | tr -d '\n')
    ipxeshasum2=$(sha256sum "$ipxe_path" | awk '{print $1}' | tr -d '\n')

    rm -f "${ipxe_path}.sha256sums"

    if [ "${ipxeshasum1}" != "${ipxeshasum1}" ]; then
        ipxe_dl_verify=1
    fi
}

function install_ipxe()
{
    local ipxe_install_path="$1"
    local temp_dir="$(mktemp -d)"
    local ipxe_path="${temp_dir}/ipxe.lkrn"

    ipxe_dl_verify=0
    download_and_verify_ipxe "$ipxe_path"

    if (( ipxe_dl_verify > 0 )); then
        >&2 echo ""
        >&2 echo "Failed to download and verify IPXE kernel binary."
        >&2 echo "In order to avoid disk partition issues, the syslinux install process"
        >&2 echo "will continue. But you must manually download and copy the ipxe x86"
        >&2 echo "lkrn file to ${ipxe_install_path}. If a file currently exists at that"
        >&2 echo "path, it has not been touched."
        >&2 echo ""
    else
        rm -f "${ipxe_install_path}"
        cp "${ipxe_path}" "${ipxe_install_path}"
    fi

    unset ipxe_dl_verify

    rm -f "$ipxe_path"
    rm -rf "$temp_dir"
}


# vim: set ft=sh: