// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.
// This module is browser compatible.

import { encodeWhitespace } from "./../_common/to_file_url.ts";
import { isAbsolute } from "./is_absolute.ts";

/**
 * Converts a path string to a file URL.
 *
 * ```ts
 * import { toFileUrl } from "@std/path/windows/to_file_url";
 *
 * toFileUrl("\\home\\foo"); // new URL("file:///home/foo")
 * toFileUrl("C:\\Users\\foo"); // new URL("file:///C:/Users/foo")
 * toFileUrl("\\\\127.0.0.1\\home\\foo"); // new URL("file://127.0.0.1/home/foo")
 * ```
 * @param path to convert to file URL
 */
export function toFileUrl(path: string): URL {
  if (!isAbsolute(path)) {
    throw new TypeError("Must be an absolute path.");
  }

  const [, hostname, pathname] = path.match(
    /^(?:[/\\]{2}([^/\\]+)(?=[/\\](?:[^/\\]|$)))?(.*)/,
  )!;
  const url = new URL("file:///");
  url.pathname = encodeWhitespace(pathname.replace(/%/g, "%25"));
  if (hostname !== undefined && hostname !== "localhost") {
    url.hostname = hostname;
    if (!url.hostname) {
      throw new TypeError("Invalid hostname.");
    }
  }
  return url;
}