export type Options = {
	/**
	Usually `'https'` or `'http'`. A trailing `:` is accepted. A value that is not a scheme, such as `'https://'`, throws a `TypeError`.

	__Note:__ A protocol that is not built in, such as `'ftp'`, is best-effort. The URL it creates is normalized, while the same URL written with that protocol is passed through as a custom protocol, unless the protocol is in `customProtocols`.

	@default 'http'
	*/
	readonly defaultProtocol?: 'https' | 'http' | (string & Record<never, never>);

	/**
	Protocols to normalize in addition to the built-in ones (`https`, `http`, `file`, `data`).

	Useful for HTTP-like custom protocols such as Electron schemes or app-specific protocols.

	The protocols should be specified without `:`, though a trailing one is accepted. The name is case-insensitive.

	__Note:__ Options that rewrite the path (`removePath`, `transformPath`, `removeDirectoryIndex`, and the percent-decoding of the path) only apply when the path starts with a `/`, as in `sindre://host/a/b` and `sindre:/a/b`. A URL whose path is opaque, such as `sindre:a/b`, has no segments for those options to work on, and a URL parser does not let the library change it, so they are silently ignored for it.

	__Note:__ `transformPath` and `removeDirectoryIndex` rebuild the path from its components, which cannot spell the two slashes of a protocol lookalike such as `sindre://host/a/s3://b/index.html`. One of them is dropped for those two options, while the library keeps both everywhere else.

	@default undefined

	@example
	```
	normalizeUrl('sindre://www.sorhus.com', {customProtocols: ['sindre']});
	//=> 'sindre://sorhus.com'

	normalizeUrl('sindre://www.sorhus.com/foo/', {customProtocols: ['sindre']});
	//=> 'sindre://sorhus.com/foo'
	```
	*/
	readonly customProtocols?: readonly string[];

	/**
	Prepends `defaultProtocol` to the URL if it's protocol-relative.

	With `false`, a protocol-relative URL stays protocol-relative, even with `defaultProtocol` or `forceHttps` set.

	@default true

	@example
	```
	normalizeUrl('//sindresorhus.com');
	//=> 'http://sindresorhus.com'

	normalizeUrl('//sindresorhus.com', {normalizeProtocol: false});
	//=> '//sindresorhus.com'
	```
	*/
	readonly normalizeProtocol?: boolean;

	/**
	Normalizes HTTPS URLs to HTTP.

	@default false

	__Note:__ changing the scheme drops the port that was the default one for the old scheme, so `forceHttp` turns `https://example.com:443` into `http://example.com` and `forceHttps` turns `http://example.com:80` into `https://example.com`. A port that is not a default for either scheme is kept.

	@example
	```
	normalizeUrl('https://sindresorhus.com');
	//=> 'https://sindresorhus.com'

	normalizeUrl('https://sindresorhus.com', {forceHttp: true});
	//=> 'http://sindresorhus.com'
	```
	*/
	readonly forceHttp?: boolean;

	/**
	Normalizes HTTP URLs to HTTPS.

	This option cannot be used with the `forceHttp` option at the same time.

	@default false

	__Note:__ changing the scheme drops the port that was the default one for the old scheme, so `forceHttp` turns `https://example.com:443` into `http://example.com` and `forceHttps` turns `http://example.com:80` into `https://example.com`. A port that is not a default for either scheme is kept.

	@example
	```
	normalizeUrl('http://sindresorhus.com');
	//=> 'http://sindresorhus.com'

	normalizeUrl('http://sindresorhus.com', {forceHttps: true});
	//=> 'https://sindresorhus.com'
	```
	*/
	readonly forceHttps?: boolean;

	/**
	Strip the [authentication](https://en.wikipedia.org/wiki/Basic_access_authentication) part of a URL.

	@default true

	@example
	```
	normalizeUrl('https://user:password@sindresorhus.com');
	//=> 'https://sindresorhus.com'

	normalizeUrl('https://user:password@sindresorhus.com', {stripAuthentication: false});
	//=> 'https://user:password@sindresorhus.com'
	```
	*/
	readonly stripAuthentication?: boolean;

	/**
	Removes hash from the URL.

	@default false

	@example
	```
	normalizeUrl('sindresorhus.com/about.html#contact');
	//=> 'http://sindresorhus.com/about.html#contact'

	normalizeUrl('sindresorhus.com/about.html#contact', {stripHash: true});
	//=> 'http://sindresorhus.com/about.html'
	```
	*/
	readonly stripHash?: boolean;

	/**
	Remove the protocol from the URL: `http://sindresorhus.com` → `sindresorhus.com`.

	It removes an `https://`, an `http://` or a leading `//` from a protocol-relative URL, and nothing else.

	__Note:__ The result is not a full URL, so normalizing it again can change it: a port that the removed protocol kept is the default one of the protocol that gets prepended next.

	@default false

	@example
	```
	normalizeUrl('https://sindresorhus.com');
	//=> 'https://sindresorhus.com'

	normalizeUrl('https://sindresorhus.com', {stripProtocol: true});
	//=> 'sindresorhus.com'
	```
	*/
	readonly stripProtocol?: boolean;

	/**
	Strip the [text fragment](https://web.dev/text-fragments/) part of the URL

	__Note:__ The text fragment will always be removed if the `stripHash` option is set to `true`, as the hash contains the text fragment.

	@default true

	@example
	```
	normalizeUrl('http://sindresorhus.com/about.html#:~:text=hello');
	//=> 'http://sindresorhus.com/about.html'

	normalizeUrl('http://sindresorhus.com/about.html#section:~:text=hello');
	//=> 'http://sindresorhus.com/about.html#section'

	normalizeUrl('http://sindresorhus.com/about.html#:~:text=hello', {stripTextFragment: false});
	//=> 'http://sindresorhus.com/about.html#:~:text=hello'

	normalizeUrl('http://sindresorhus.com/about.html#section:~:text=hello', {stripTextFragment: false});
	//=> 'http://sindresorhus.com/about.html#section:~:text=hello'
	```
	*/
	readonly stripTextFragment?: boolean;

	/**
	Removes `www.` from the URL.

	__Note:__ A `www.` that is not followed by a proper domain is left alone, so `www.com` and `www.a.b` are not changed.

	@default true

	@example
	```
	normalizeUrl('http://www.sindresorhus.com');
	//=> 'http://sindresorhus.com'

	normalizeUrl('http://www.sindresorhus.com', {stripWWW: false});
	//=> 'http://www.sindresorhus.com'
	```
	*/
	readonly stripWWW?: boolean;

	/**
	Removes query parameters that matches any of the provided strings or regexes. The match is against the percent-decoded key, the way `URLSearchParams` reads one, so `+` is a space and `%2F` is a slash: write `a/b` rather than `a%2Fb`.

	Global and sticky regex flags are stripped.

	@default [/^utm_\w+/i]

	@example
	```
	normalizeUrl('www.sindresorhus.com?foo=bar&ref=test_ref', {
		removeQueryParameters: ['ref']
	});
	//=> 'http://sindresorhus.com/?foo=bar'
	```

	If a boolean is provided, `true` will remove all the query parameters.

	```
	normalizeUrl('www.sindresorhus.com?foo=bar', {
		removeQueryParameters: true
	});
	//=> 'http://sindresorhus.com'
	```

	`false` will not remove any query parameter.

	```
	normalizeUrl('www.sindresorhus.com?foo=bar&utm_medium=test&ref=test_ref', {
		removeQueryParameters: false
	});
	//=> 'http://sindresorhus.com/?foo=bar&ref=test_ref&utm_medium=test'
	```
	*/
	readonly removeQueryParameters?: ReadonlyArray<RegExp | string> | boolean;

	/**
	Keeps only query parameters that matches any of the provided strings or regexes. The match is against the percent-decoded key, the same as `removeQueryParameters`. An empty array matches nothing, so it removes every parameter, the same as the `true` of `removeQueryParameters`.

	__Note:__ It overrides the `removeQueryParameters` option.

	Global and sticky regex flags are stripped.

	@default undefined

	@example
	```
	normalizeUrl('https://sindresorhus.com?foo=bar&ref=unicorn', {
		keepQueryParameters: ['ref']
	});
	//=> 'https://sindresorhus.com/?ref=unicorn'
	```
	*/
	readonly keepQueryParameters?: ReadonlyArray<RegExp | string>;

	/**
	Removes trailing slash.

	__Note:__ the sole `/` of a root path is removed too, unless the `removeSingleSlash` option is set to `false` **and** the input wrote that slash itself.

	__Note:__ `removeSingleSlash: false` reads the trailing slash off the input as it was written, so a slash that belongs to a dot segment a URL parser resolves away still counts. `https://example.com/a/../` and `https://example.com/a/..` are the same URL, but only the first keeps the root slash.

	@default true

	@example
	```
	normalizeUrl('http://sindresorhus.com/redirect/');
	//=> 'http://sindresorhus.com/redirect'

	normalizeUrl('http://sindresorhus.com/redirect/', {removeTrailingSlash: false});
	//=> 'http://sindresorhus.com/redirect/'

	normalizeUrl('http://sindresorhus.com/', {removeTrailingSlash: false});
	//=> 'http://sindresorhus.com'
	```
	*/
	readonly removeTrailingSlash?: boolean;

	/**
	Remove a sole `/` pathname in the output. This option is independent of `removeTrailingSlash`.

	The `/` is kept when a query or a hash follows it, as in `https://sindresorhus.com/?a=1`.

	@default true

	@example
	```
	normalizeUrl('https://sindresorhus.com/');
	//=> 'https://sindresorhus.com'

	normalizeUrl('https://sindresorhus.com/', {removeSingleSlash: false});
	//=> 'https://sindresorhus.com/'
	```
	*/
	readonly removeSingleSlash?: boolean;

	/**
	Removes the default directory index file from path that matches any of the provided strings or regexes. The match is against the percent-decoded component, the same as `transformPath` is given, so `index.html` matches a path spelled `index%2Ehtml`. It runs after `transformPath`, so it also removes an index file the function leaves at the end.

	When `true`, the regex `/^index\.[a-z]+$/` is used.

	__Note:__ removing the index leaves a trailing slash on what is left, whether or not the input wrote one, so `http://example.com/foo/index.html` becomes `http://example.com/foo/` and then `http://example.com/foo`. The `removeTrailingSlash` option decides whether that slash stays.

	Global and sticky regex flags are stripped.

	@default false

	@example
	```
	normalizeUrl('www.sindresorhus.com/foo/default.php', {
		removeDirectoryIndex: [/^default\.[a-z]+$/]
	});
	//=> 'http://sindresorhus.com/foo'
	```
	*/
	readonly removeDirectoryIndex?: boolean | ReadonlyArray<RegExp | string>;

	/**
	Removes an explicit port number from the URL.

	Port 443 is always removed from HTTPS URLs and 80 is always removed from HTTP URLs regardless of this option.

	@default false

	@example
	```
	normalizeUrl('sindresorhus.com:123', {
		removeExplicitPort: true
	});
	//=> 'http://sindresorhus.com'
	```
	*/
	readonly removeExplicitPort?: boolean;

	/**
	Sorts the query parameters by key, in code unit order, so an uppercase letter sorts before a lowercase one and a digit before a letter. Parameters that share a key keep the order they were written in.

	__Note:__ The option only changes the order. The query is written the same way either way (see `normalizeUrl`).

	@default true

	@example
	```
	normalizeUrl('www.sindresorhus.com?b=two&a=one&c=three', {
		sortQueryParameters: false
	});
	//=> 'http://sindresorhus.com/?b=two&a=one&c=three'
	```
	*/
	readonly sortQueryParameters?: boolean;

	/**
	Controls how query parameters with empty values are formatted.

	- `'preserve'` - Keep the original format (`?key` stays `?key`, `?key=` stays `?key=`). If the same key appears with both formats (`?a&a=`), all instances will use the format without `=`.
	- `'always'` - Always include `=` for empty values (`?key` becomes `?key=`)
	- `'never'` - Never include `=` for empty values (`?key=` becomes `?key`)

	@default 'preserve'

	@example
	```
	normalizeUrl('www.sindresorhus.com?a&b=', {emptyQueryValue: 'always'});
	//=> 'http://sindresorhus.com/?a=&b='

	normalizeUrl('www.sindresorhus.com?a&b=', {emptyQueryValue: 'never'});
	//=> 'http://sindresorhus.com/?a&b'
	```
	*/
	readonly emptyQueryValue?: 'preserve' | 'always' | 'never';

	/**
	Removes the entire URL path, leaving the host with no path. The query and the hash stay. It takes precedence over the `transformPath` option.

	@default false

	@example
	```
	normalizeUrl('https://example.com/path/to/page', {
		removePath: true
	});
	//=> 'https://example.com'
	```
	*/
	readonly removePath?: boolean;

	/**
	Custom function to transform the URL path components.

	The function receives an array of non-empty path components and should return a modified array. Returning nothing removes the path. The components are percent-decoded, so an unreserved escape has become the character it stands for by the time the function sees it, and one it returns is not decoded again. It runs before `removeDirectoryIndex`, so the function still sees the index file, and it is skipped when `removePath` is set.

	@default false

	@example
	```
	// Keep only the first path component
	normalizeUrl('https://example.com/api/v1/users', {
		transformPath: (pathComponents) => pathComponents.slice(0, 1)
	});
	//=> 'https://example.com/api'

	// Remove specific components
	normalizeUrl('https://example.com/admin/users', {
		transformPath: (pathComponents) => pathComponents.filter(c => c !== 'admin')
	});
	//=> 'https://example.com/users'
	```
	*/
	readonly transformPath?: ((pathComponents: string[]) => readonly string[] | undefined) | false;
};

/**
[Normalize](https://en.wikipedia.org/wiki/URL_normalization) a URL.

URLs with custom protocols are not normalized and just passed through by default. Supported protocols are: `https`, `http`, `file`, and `data`. Use the `customProtocols` option to add support for additional protocols.

Human-friendly URLs with basic auth (for example, `user:password@sindresorhus.com`) are not handled because basic auth conflicts with custom protocols. [Basic auth URLs are also deprecated.](https://developer.mozilla.org/en-US/docs/Web/HTTP/Authentication#access_using_credentials_in_the_url)

A scheme with a dot in it followed by `//` is a custom protocol, so it is passed through as well and nothing in the URL is normalized. `example.com/path` is a host and gets `http:` prepended, but `example.com://host/path` is a scheme named `example.com` and is left alone. Use the `customProtocols` option to normalize one on purpose.

Whatever the options, a normalized URL also gets these changes:

- Tab, carriage return, and line feed are removed from anywhere, as a URL parser does. Whitespace and C0 controls are removed from the ends, including U+00A0 and a byte order mark, which are often left over from copying a URL. Other whitespace inside the URL is kept, and escaped where a URL parser escapes it.
- A URL parser lowercases the protocol. For a built-in protocol, it also lowercases the host, converts an internationalized host to Punycode, resolves `.` and `..` path segments, and removes a default port.
- Trailing dots are removed from a domain host, unless that changes the name: `159.189.213..` keeps them, since `159.189.213` is the IPv4 address `159.189.0.213`. The host of a custom protocol is opaque, so its dots are kept.
- Duplicate slashes in the path are removed, except the two of a protocol-like segment such as `/https://`.
- Percent escapes are uppercased (`%2f` → `%2F`), except in the media type of a data URL, where percent-looking text is literal MIME content. Escapes of unreserved characters (letters, digits, `-`, `.`, `_`, `~`) are decoded (`%7E` → `~`), except in a fragment, the media type of a data URL, the host of a custom protocol, and a path that does not start with `/`. Fragment escapes stay encoded so they cannot become text directives. The path and the query also decode other escapes where the character means the same unescaped, as in `%5B` → `[`. Escapes that would change the structure, like `%2F`, `%3F`, `%23`, and `%26`, stay escaped, so `%2F` and `/` stay different.
- The query is written the way `URLSearchParams` writes it: a space in a value is `+`, a space in a key is `%20`, a `?` is `%3F`, and a `%` that starts no escape is `%25`. Empty parameters, as in `?a=1&&b=2`, are removed. This happens with `sortQueryParameters: false` too. An escape that is not valid UTF-8 becomes U+FFFD, as `URLSearchParams` decodes it, so `?q=%E9` becomes `?q=%EF%BF%BD`, which changes the value for a server that reads the query as Latin-1.
- A data URL gets its MIME type and `charset` value lowercased. `text/plain` is removed when nothing follows it, and so is `charset=us-ascii` on `text/plain`. Quotes are removed from a parameter value that does not need them, and whitespace is removed from the ends of base64 data.

@param url - URL to normalize, including [data URL](https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/Data_URIs).

@example
```
import normalizeUrl from 'normalize-url';

normalizeUrl('sindresorhus.com');
//=> 'http://sindresorhus.com'

normalizeUrl('//www.sindresorhus.com:80/../baz?b=bar&a=foo');
//=> 'http://sindresorhus.com/baz?a=foo&b=bar'
```
*/
export default function normalizeUrl(url: string, options?: Options): string;