#!/bin/sh -e

dst="/$__object_id"

if [ ! -f "$dst" ]
then
    echo 'absent'
    exit 0
fi

if [ ! -f "$__object/parameter/sum" ]
then
    echo 'present'
    exit 0
fi

sum_should="$( cat "$__object/parameter/sum" )"

if [ -f "$__object/parameter/cmd-sum" ]
then
    # shellcheck disable=SC2059
    sum_is="$( eval "$( printf \
        "$( cat "$__object/parameter/cmd-sum" )" \
        "$dst" )" )"
else
    os="$( "$__explorer/os" )"

    if echo "$sum_should" | grep -Eq '^[0-9]+\s[0-9]+$'
    then
        sum_is="$( cksum "$dst" | awk '{print $1" "$2}' )"

    elif echo "$sum_should" | grep -Eiq '^md5:[a-f0-9]{32}$'
    then
        case "$os" in
            freebsd)
                sum_is="md5:$( md5 -q "$dst" )"
            ;;
            *)
                sum_is="md5:$( md5sum "$dst" | awk '{print $1}' )"
            ;;
        esac

    elif echo "$sum_should" | grep -Eiq '^sha1:[a-f0-9]{40}$'
    then
        case "$os" in
            freebsd)
                sum_is="sha1:$( sha1 -q "$dst" )"
            ;;
            *)
                sum_is="sha1:$( sha1sum "$dst" | awk '{print $1}' )"
            ;;
        esac

    elif echo "$sum_should" | grep -Eiq '^sha256:[a-f0-9]{64}$'
    then
        case "$os" in
            freebsd)
                sum_is="sha256:$( sha256 -q "$dst" )"
            ;;
            *)
                sum_is="sha256:$( sha256sum "$dst" | awk '{print $1}' )"
            ;;
        esac
    fi
fi

if [ -z "$sum_is" ]
then
    echo 'no checksum from target' >&2
    exit 1
fi

if [ "$sum_is" = "$sum_should" ]
then
    echo 'present'
else
    echo 'mismatch'
fi