#!/bin/sh

set -eu

container_name="${1:-DockDeck}"
icon_url="${2:-}"
template_path="/boot/config/plugins/dockerMan/templates-user/my-${container_name}.xml"
persistent_dir="/var/lib/docker/unraid/images"
runtime_dir="/usr/local/emhttp/state/plugins/dynamix.docker.manager/images"

fail() {
  printf 'DockDeck icon refresh failed: %s\n' "$1" >&2
  exit 1
}

[ "$(id -u)" -eq 0 ] || fail "run this helper as root on the Unraid host"

case "$container_name" in
  "" | *[!A-Za-z0-9_.-]*) fail "invalid container name" ;;
esac

if [ -z "$icon_url" ] && [ -f "$template_path" ]; then
  icon_url="$(sed -n 's#.*<Icon>\(.*\)</Icon>.*#\1#p' "$template_path" | head -n 1)"
fi

case "$icon_url" in
  http://* | https://*) ;;
  *) fail "provide an HTTP(S) icon URL or a user template containing <Icon>" ;;
esac

temporary_icon="$(mktemp /tmp/dockdeck-icon.XXXXXX)"
trap 'rm -f "$temporary_icon"' EXIT HUP INT TERM

curl --fail --silent --show-error --location \
  --connect-timeout 5 --max-time 20 \
  "$icon_url" --output "$temporary_icon"

[ "$(file -b --mime-type "$temporary_icon")" = "image/png" ] || \
  fail "the downloaded asset is not a real PNG"

mkdir -p "$persistent_dir" "$runtime_dir"
install -m 0644 -o root -g root \
  "$temporary_icon" "$persistent_dir/${container_name}-icon.png"
install -m 0644 -o root -g root \
  "$temporary_icon" "$runtime_dir/${container_name}-icon.png"

printf 'Refreshed both Unraid icon caches for %s from %s\n' \
  "$container_name" "$icon_url"