#!/bin/sh
set -eu

backend_base_url=${BACKEND_BASE_URL-/api}
case "$backend_base_url" in
  ""|/|/api|/api/) ;;
  http://*|https://*)
    if printf '%s' "$backend_base_url" | grep -Eq '[[:space:]]|^https?://[^/]*@'; then
      echo "Invalid BACKEND_BASE_URL: credentials and whitespace are not allowed" >&2
      exit 2
    fi
    ;;
  *)
    echo "Invalid BACKEND_BASE_URL: use empty/root, /api, or an absolute http(s) URL" >&2
    exit 2
    ;;
esac
runtime_config=$(jq -cn --arg backend_base_url "$backend_base_url" \
  '{backendBaseUrl: $backend_base_url}')
printf 'window.__THOTHII_CONFIG__ = %s;\n' "$runtime_config" \
  > /usr/share/nginx/html/config.js

if [ "$#" -gt 0 ]; then
  exec "$@"
fi

exec nginx -g 'daemon off;'