<?php
namespace Fisharebest\Webtrees;

/**
 * webtrees: online genealogy
 * Copyright (C) 2015 webtrees development team
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */

/**
 * Interface ModuleTabInterface - Classes and libraries for module system
 */
interface ModuleTabInterface {
	/**
	 * The user can re-arrange the tab order, but until they do, this
	 * is the order in which tabs are shown.
	 *
	 * @return integer
	 */
	public function defaultTabOrder();

	/**
	 * Generate the HTML content of this tab.
	 *
	 * @return string
	 */
	public function getTabContent();

	/**
	 * Is this tab empty?  If so, we don't always need to display it.
	 * @return boolean
	 */
	public function hasTabContent();

	/**
	 * Can this tab load asynchronously?
	 *
	 * @return boolean
	 */
	public function canLoadAjax();

	/**
	 * Any content (e.g. Javascript) that needs to be rendered before the tabs.
	 *
	 * This function is probably not needed, as there are better ways to achieve this.
	 *
	 * @return string
	 */
	public function getPreLoadContent();

	/**
	 * A greyed out tab has no actual content, but may perhaps have
	 * options to create content.
	 *
	 * @return boolean
	 */
	public function isGrayedOut();
}