/**
 * Fetch headers.
 *
 * @see https://developer.mozilla.org/en-US/docs/Web/API/Headers
 */
export default interface IHeaders extends Iterable<[string, string]> {
	/**
	 * Appends a new value onto an existing header inside a Headers object, or adds the header if it does not already exist.
	 *
	 * @param name Name.
	 * @param value Value.
	 */
	append(name: string, value: string): void;

	/**
	 * Removes an header.
	 *
	 * @param name Name.
	 */
	delete(name: string): void;

	/**
	 * Returns header value.
	 *
	 * @param name Name.
	 * @returns Value.
	 */
	get(name: string): string | null;

	/**
	 * Sets a new value for an existing header inside a Headers object, or adds the header if it does not already exist.
	 *
	 * @param name Name.
	 * @param value Value.
	 */
	set(name: string, value: string): void;

	/**
	 * Returns whether an Headers object contains a certain key.
	 *
	 * @param name Name.
	 * @returns "true" if the Headers object contains the key.
	 */
	has(name: string): boolean;

	/**
	 * Executes a callback function once per each key/value pair in the Headers object.
	 *
	 * @param callback Callback.
	 */
	forEach(callback: (name: string, value: string, object: IHeaders) => void): void;

	/**
	 * Returns an iterator, allowing you to go through all keys of the key/value pairs contained in this object.
	 *
	 * @returns Iterator.
	 */
	keys(): IterableIterator<string>;

	/**
	 * Returns an iterator, allowing you to go through all values of the key/value pairs contained in this object.
	 *
	 * @returns Iterator.
	 */
	values(): IterableIterator<string>;

	/**
	 * Returns an iterator, allowing you to go through all key/value pairs contained in this object.
	 *
	 * @returns Iterator.
	 */
	entries(): IterableIterator<[string, string]>;

	/**
	 * Iterator.
	 *
	 * @returns Iterator.
	 */
	[Symbol.iterator](): IterableIterator<[string, string]>;
}