#!/usr/bin/env bash
set -eu

version=0.7.1
arch="$(uname -m)"
tarball="shellcheck-v$version.linux.$arch.tar.xz"
declare -A sha256=(
    [aarch64]=b50cc31509b354ab5bbfc160bc0967567ed98cd9308fd43f38551b36cccc4446
    [x86_64]=64f17152d96d7ec261ad3086ed42d18232fcb65148b44571b564d688269d36c8
)

check_version() {
    out="$(shellcheck --version 2>/dev/null)" && [[ "$out" = *"
version: $version
"* ]]
}

if ! check_version; then
    tmpdir="$(mktemp -d)"
    trap 'rm -r "$tmpdir"' EXIT
    cd "$tmpdir"
    wget -nv "https://github.com/koalaman/shellcheck/releases/download/v$version/$tarball"
    sha256sum -c <<<"${sha256[$arch]} $tarball"
    tar -xJf "$tarball" --no-same-owner --strip-components=1 -C /usr/local/bin "shellcheck-v$version/shellcheck"
    check_version
fi