#!/bin/sh
set -eu

log() {
    echo "$(date -u '+%Y-%m-%dT%H:%M:%SZ') $*"
}

if [ "$#" -eq 0 ]; then
    log "no packages supplied; nothing to ensure"
    exit 0
fi

log "ensuring packages: $*"

missing_packages=""
for pkg in "$@"; do
    if ! command -v "$pkg" >/dev/null 2>&1; then
        if [ -n "$missing_packages" ]; then
            missing_packages="$missing_packages $pkg"
        else
            missing_packages="$pkg"
        fi
    fi
done

if [ -n "$missing_packages" ]; then
    log "installing $missing_packages"
    set -- $missing_packages
    apk add --no-cache "$@" >/dev/null 2>&1
else
    log "all requested packages already available"
fi