import urljoin from "url-join";
import parse from "url-parse";

import { trimSuffix } from "./string.ts";
import { throwValidationError } from "./validation.ts";

export const DEFAULT_S5_PORTAL_URL = "https://localhost:5522";

/**
 * @deprecated please use DEFAULT_S5_PORTAL_URL.
 */
export const defaultS5PortalUrl = DEFAULT_S5_PORTAL_URL;

export const URI_S5_PREFIX = "s5://";

/**
 * @deprecated please use URI_S5_PREFIX.
 */
export const uriS5Prefix = URI_S5_PREFIX;

/**
 * Returns the default portal URL.
 *
 * @returns - The portal URL.
 */
export function defaultPortalUrl(): string {
  /* istanbul ignore next */
  if (typeof window === "undefined") return "/"; // default to path root on ssr
  return window.location.origin;
}

/**
 * Adds a subdomain to the given URL.
 *
 * @param url - The URL.
 * @param subdomain - The subdomain to add.
 * @returns - The final URL.
 */
export function addUrlSubdomain(url: string, subdomain: string): string {
  const urlObj = new URL(url);
  urlObj.hostname = `${subdomain}.${urlObj.hostname}`;
  const str = urlObj.toString();
  return trimSuffix(str, "/");
}

/**
 * Adds a query to the given URL.
 *
 * @param url - The URL.
 * @param query - The query parameters.
 * @returns - The final URL.
 */
export function addUrlQuery(
  url: string,
  query: { [key: string]: string | undefined },
): string {
  const parsed = parse(url, true);
  // Combine the desired query params with the already existing ones.
  query = { ...parsed.query, ...query };
  parsed.set("query", query);
  return parsed.toString();
}

/**
 * Prepends the prefix to the given string only if the string does not already start with the prefix.
 *
 * @param str - The string.
 * @param prefix - The prefix.
 * @returns - The prefixed string.
 */
export function ensurePrefix(str: string, prefix: string): string {
  if (!str.startsWith(prefix)) {
    str = `${prefix}${str}`;
  }
  return str;
}

/**
 * Ensures that the given string is a URL.
 *
 * @param url - The given string.
 * @returns - The URL.
 */
export function ensureUrl(url: string): string {
  if (url.startsWith("http://")) {
    return url;
  }
  return ensurePrefix(url, "https://");
}

/**
 * Ensures that the given string is a URL with a protocol prefix.
 *
 * @param url - The given string.
 * @returns - The URL.
 */
export function ensureUrlPrefix(url: string): string {
  if (url === "localhost") {
    return "http://localhost/";
  }

  if (!/^https?:(\/\/)?/i.test(url)) {
    return `https://${url}`;
  }
  return url;
}

/**
 * Properly joins paths together to create a URL. Takes a variable number of
 * arguments.
 *
 * @param args - Array of URL parts to join.
 * @returns - Final URL constructed from the input parts.
 */
export function makeUrl(...args: string[]): string {
  if (args.length === 0) {
    throwValidationError("args", args, "parameter", "non-empty");
  }
  return ensureUrl(args.reduce((acc, cur) => urljoin(acc, cur)));
}