<?php
/**
 * Capability helpers.
 *
 * Everything the plugin gates on goes through here, so a site can widen or
 * narrow access with one filter instead of hunting for capability strings.
 *
 * Two kinds of question are answered here, and they are kept apart on purpose.
 *
 * "May this person use PageCore" is the plugin's own question, and the plugin
 * lets a site answer it differently through a filter. "May this person install
 * a plugin" is not the plugin's question at all: it is WordPress's, the answer
 * belongs to WordPress, and a filter that could change it would turn the
 * capability required to open a PageCore screen into the capability required
 * to put arbitrary code on the server. So the core capabilities below are
 * named here for consistency and read from here for tidiness, but they are not
 * filterable and they are never collapsed into the plugin's own.
 *
 * The one place that cannot use this class is Requirements, which runs before
 * the autoloader and therefore before this file exists.
 *
 * @package PageCore
 */

namespace PageCore;

defined( 'ABSPATH' ) || exit;

/**
 * Resolves the capabilities the plugin checks.
 */
class Capabilities {

	/**
	 * WordPress capabilities for the privileged things an import does.
	 *
	 * Deliberately not filterable. See the note at the top of this file.
	 */
	const CORE_ACTIONS = array(
		'import'           => 'import',
		'upload_files'     => 'upload_files',
		'install_plugins'  => 'install_plugins',
		'activate_plugins' => 'activate_plugins',
		'install_themes'   => 'install_themes',
		'switch_themes'    => 'switch_themes',
	);

	/**
	 * Whether the current user may take one privileged action.
	 *
	 * @param string $action Key from CORE_ACTIONS.
	 * @return bool False for an action nobody named, so a typo denies rather
	 *               than permits.
	 */
	public static function can( $action ) {
		if ( ! isset( self::CORE_ACTIONS[ $action ] ) ) {
			return false;
		}

		return current_user_can( self::CORE_ACTIONS[ $action ] );
	}

	/**
	 * Whether the current user may run a demo import.
	 *
	 * An import writes content and changes site settings, so it needs both
	 * the plugin's own capability and WordPress's for importing.
	 *
	 * @return bool
	 */
	public static function current_user_can_import() {
		return self::current_user_can_manage() && self::can( 'import' );
	}

	/**
	 * Capability required to administer PageCore itself.
	 *
	 * @return string
	 */
	public static function manage() {
		return 'manage_options';
	}

	/**
	 * Whether the current user may administer PageCore.
	 *
	 * @return bool
	 */
	public static function current_user_can_manage() {
		return current_user_can( self::manage() );
	}
}