<?php

namespace MediaWiki\Permissions\Hook;

use MessageSpecifier;
use Title;
use User;

/**
 * This is a hook handler interface, see docs/Hooks.md.
 * Use the hook name "getUserPermissionsErrorsExpensive" to register handlers implementing this interface.
 *
 * @stable to implement
 * @ingroup Hooks
 */
interface GetUserPermissionsErrorsExpensiveHook {
	/**
	 * This hook is equal to getUserPermissionsErrors, but it is called only if
	 * expensive checks are enabled. Use this hook to add a permissions error when
	 * permissions errors are checked for. Return false if the user can't do it, and
	 * populate $result with the reason in the form of [ messagename, param1, param2,
	 * ... ] or a MessageSpecifier instance (you might want to use ApiMessage to
	 * provide machine-readable details for the API).
	 *
	 * @since 1.35
	 *
	 * @param Title $title Title being checked against
	 * @param User $user Current user
	 * @param string $action Action being checked
	 * @param array|string|MessageSpecifier &$result User permissions error to add. If none, return true.
	 *   For consistency, error messages should be plain text with no special coloring,
	 *   bolding, etc. to show that they're errors; presenting them properly to the
	 *   user as errors is done by the caller.
	 * @return bool|void True or no return value to continue or false to abort
	 */
	public function onGetUserPermissionsErrorsExpensive( $title, $user, $action,
		&$result
	);
}
