#!/usr/bin/env bash

set -eo pipefail


function usage() {
  cat > /dev/stdout <<EOF
Usage:
  run_docker [OPTIONS]

  Optional flags:
    -h, --help                  Show this information and exit
    --pre-built                 Use the prebuilt pyodide image.
                                This is ignored if the env var PYODIDE_DOCKER_IMAGE is set
    -p, --port <port>           System port to which to forward.
                                This is ignored if the env var PYODIDE_SYSTEM_PORT is set

  Prerequisites:
    Docker has to be set up on your system
EOF
}

function error() {
  usage
  exit 255
}


PYODIDE_IMAGE_TAG="8"
PYODIDE_PREBUILT_IMAGE_TAG="0.16.0b1"
DEFAULT_PYODIDE_DOCKER_IMAGE="iodide/pyodide-env:${PYODIDE_IMAGE_TAG}"
DEFAULT_PYODIDE_SYSTEM_PORT="8000"

while [[ $# -gt 0 ]]
do
  key="$1"
  case $key in
      -h|--help)
        usage
        exit 0
      ;;
      --pre-built)
        if [[ -n ${PYODIDE_DOCKER_IMAGE} ]]; then
          echo "WARNING: will use the env var PYODIDE_DOCKER_IMAGE=${PYODIDE_DOCKER_IMAGE},
          the flag --pre-built has no effect"
        fi
        DEFAULT_PYODIDE_DOCKER_IMAGE="iodide/pyodide:${PYODIDE_PREBUILT_IMAGE_TAG}"
        shift
      ;;
      -p|--port)
        if [ "$#" -lt 2 ]; then
          >&2 echo "port cannot be empty"
          error
        fi
        if [[ -n ${PYODIDE_SYSTEM_PORT} ]]; then
          echo "WARNING: will use the env var PYODIDE_SYSTEM_PORT=${PYODIDE_SYSTEM_PORT} instead of the provided port"
        fi
        DEFAULT_PYODIDE_SYSTEM_PORT=$2
        shift 2
      ;;
      *)
        >&2 echo "Unknown option $1"
        error
      ;;
  esac
done

PYODIDE_DOCKER_PORT=${PYODIDE_DOCKER_PORT:-"8000"}
PYODIDE_SYSTEM_PORT=${PYODIDE_SYSTEM_PORT:-${DEFAULT_PYODIDE_SYSTEM_PORT}}
PYODIDE_DOCKER_IMAGE=${PYODIDE_DOCKER_IMAGE:-${DEFAULT_PYODIDE_DOCKER_IMAGE}}

exec docker run \
    -p "$PYODIDE_SYSTEM_PORT":"$PYODIDE_DOCKER_PORT" \
    -it --rm \
    -v $PWD:/src \
    --user root -e NB_UID=$UID -e NB_GID=$GID \
    "${PYODIDE_DOCKER_IMAGE}" \
    /bin/bash