import * as trpcNext from "@trpc/server/adapters/next";
import { SALEOR_AUTHORIZATION_BEARER_HEADER, SALEOR_API_URL_HEADER } from "@saleor/app-sdk/const";
import { inferAsyncReturnType } from "@trpc/server";

const getBaseUrl = (headers: { [name: string]: string | string[] | undefined }): string => {
  const { host, "x-forwarded-proto": xForwardedProto = "http" } = headers;

  const xForwardedProtos = Array.isArray(xForwardedProto)
    ? xForwardedProto.join(",")
    : xForwardedProto;
  const protocols = xForwardedProtos.split(",");
  // prefer https over other protocols
  const protocol = protocols.find((el) => el === "https") || protocols[0];

  return `${protocol}://${host}`;
};

export const createTrpcContext = async ({ res, req }: trpcNext.CreateNextContextOptions) => {
  const baseUrl = getBaseUrl(req.headers);

  return {
    token: req.headers[SALEOR_AUTHORIZATION_BEARER_HEADER] as string | undefined,
    saleorApiUrl: req.headers[SALEOR_API_URL_HEADER] as string | undefined,
    appId: undefined as undefined | string,
    ssr: undefined as undefined | boolean,
    baseUrl,
  };
};

export type TrpcContext = inferAsyncReturnType<typeof createTrpcContext>;