#!/usr/bin/env bash

root=${PORTICAL_UPNP_ROOT_URL}
duration=${PORTICAL_POLL_INTERVAL-15}
label="portical.upnp.forward"
verbose=false
force=false

while (( "$#" )); do
  case $1 in
    -r | --root) root="$2"; shift 2 ;;
    -d | --duration) duration="$2"; shift 2 ;;
    -l | --label) label="$2"; shift 2 ;;
    -v | --verbose) verbose=true; shift ;;
    -f | --force) force=true; shift ;;
    *) break ;;
  esac
done


function run_cmd() {
    if $verbose; then
        "$@"
    else
        "$@" > /dev/null 2>&1
    fi

    local status=$?
    if [ $status -ne 0 ]; then
        echo "Error: Command '$*' failed with status $status"
        exit $status
    fi
}

function forward() {
  local network_driver=$1
  local external_port=$2
  local internal_port=$3
  local protocol=$4
  local machine=$5
  local description="portical: (${external_port}:${internal_port}/${protocol}) ${machine}"

  echo "Setting up ${description}..."

  case $network_driver in
    macvlan | ipvlan)
      local network="container:${machine}"
      ;;

    host | bridge)
      local network="host"
      ;;

    *)
      echo "Unsupported network driver: ${network_driver}. Skipping..."
      return
      ;;
  esac

  if [ "$force" == false  ] && [[ $(upnpc ${root:+-u "$root"} -l) == *"${description}"* ]]; then
    echo "Rule already exists. Skipping..."
    return
  else
      echo -n "Removing existing rule... "
      run_cmd docker run --rm --network ${network} danielbodart/portical \
        upnpc ${root:+-u "$root"} -d "${external_port}" "${protocol}"
      echo "DONE"
  fi

  echo -n "Adding new rule... "
  run_cmd docker run --rm --network ${network} danielbodart/portical \
    upnpc ${root:+-u "$root"} -e "${description}" -r "${internal_port}" "${external_port}" "${protocol}"
  echo "DONE"

}


function process_container() {
    local container=$1

    label_value=$(docker inspect --format "{{ index .Config.Labels \"${label}\" }}" "$container")
    network_name=$(docker inspect -f '{{range $key, $_ := .NetworkSettings.Networks}}{{ $key }}{{end}}' "$container")
    network_driver=$(docker network inspect -f '{{.Driver}}' "$network_name")

    if [[ ${label_value} == "published" ]]; then
      echo "Extracting published port for ${container}... "
      label_value="$(docker inspect --format='{{ range $key, $value := .NetworkSettings.Ports }}{{ range $value }}{{.HostPort}}:{{ $key }}
{{ end }}{{ end }}' "${container}" | sort | uniq | tr '\n' ',' | sed 's/:[0-9]*//' )"
    fi

    IFS=',' read -ra rules <<< "${label_value}"

    for rule in "${rules[@]}"; do
      if [[ ${rule} =~ ([0-9]+)(:([0-9]+))?(\/(tcp|udp))? ]]; then
          external_port="${BASH_REMATCH[1]}"
          internal_port="${BASH_REMATCH[3]:-${external_port}}"
          protocol="${BASH_REMATCH[5]}"

          if [[ $protocol == "" ]]; then
            forward "$network_driver" "$external_port" "$internal_port" tcp "$container"
            forward "$network_driver" "$external_port" "$internal_port" udp "$container"
          else
            forward "$network_driver" "$external_port" "$internal_port" "$protocol" "$container"
          fi
      fi
    done
}

function update() {
    echo "Finding all containers with label '${label}' set..."
    docker ps --filter "label=${label}" --format '{{.Names}}' | while read container; do
        process_container "$container"
    done

    echo "All portical rules:"
    upnpc ${root:+-u "$root"} -l | grep portical
}

function listen() {
    # Do an initial update just for good measure
    update
    echo "Listening for Docker 'start' events with label '${label}'..."
    docker events --filter "label=${label}" --filter "type=container" --filter "event=start" --format '{{.Actor.Attributes.name}}' | while read container; do
        process_container "$container"
    done
}

function poll() {
  while true; do
    update
    echo "Sleeping for ${duration} seconds..."
    sleep ${duration}
  done
}


command="${1-update}"
shift

if declare -f "$command" > /dev/null; then
  set +e
  "$command" "$@"
else
  echo "Error: '$command' is not a valid command." >&2
  exit 1
fi