<?php
/**
 * Capabilities.
 *
 * @package ElevenRank
 * @since   1.0.0
 */

namespace ElevenRank;

defined( 'ABSPATH' ) || exit;

/**
 * Defines the plugin's capabilities and keeps administrators from losing them.
 *
 * Administrators receive every capability when the plugin is activated. As a
 * safety net (multisite sites created later, a role editor stripping caps) anyone
 * who can `manage_options` is also treated as holding all of them, so an
 * administrator can never be locked out of the settings.
 *
 * @since 1.0.0
 */
final class Capabilities {

	const MANAGE             = 'elevenrank_manage';
	const MANAGE_REDIRECTS   = 'elevenrank_manage_redirects';
	const VIEW_404           = 'elevenrank_view_404';
	const EDIT_POST_SEO      = 'elevenrank_edit_post_seo';
	const EDIT_POST_ADVANCED = 'elevenrank_edit_post_advanced';
	const IMPORT             = 'elevenrank_import';

	/**
	 * Every capability the plugin defines.
	 *
	 * @since 1.0.0
	 *
	 * @return string[]
	 */
	public static function all(): array {
		return array(
			self::MANAGE,
			self::MANAGE_REDIRECTS,
			self::VIEW_404,
			self::EDIT_POST_SEO,
			self::EDIT_POST_ADVANCED,
			self::IMPORT,
		);
	}

	/**
	 * Registers the runtime fallback for administrators.
	 *
	 * @since 1.0.0
	 *
	 * @return void
	 */
	public function hooks(): void {
		add_filter( 'user_has_cap', array( $this, 'grant_to_administrators' ) );
	}

	/**
	 * Treats anyone who can manage options as holding every plugin capability.
	 *
	 * @since 1.0.0
	 *
	 * @param array<string, bool> $allcaps The user's capabilities.
	 * @return array<string, bool>
	 */
	public function grant_to_administrators( $allcaps ) {
		if ( empty( $allcaps['manage_options'] ) ) {
			return $allcaps;
		}

		foreach ( self::all() as $capability ) {
			$allcaps[ $capability ] = true;
		}

		return $allcaps;
	}

	/**
	 * Stores every capability on the administrator role of the current site.
	 *
	 * @since 1.0.0
	 *
	 * @return void
	 */
	public function add_to_administrator(): void {
		$role = get_role( 'administrator' );

		if ( null === $role ) {
			return;
		}

		foreach ( self::all() as $capability ) {
			$role->add_cap( $capability );
		}
	}

	/**
	 * Lets editors and authors use the SEO box on the posts they can edit.
	 *
	 * Editors may also change the advanced fields (robots, canonical link). Site owners can
	 * change this later; administrators are not affected.
	 *
	 * @since 1.0.0
	 *
	 * @return void
	 */
	public function add_defaults(): void {
		$grants = array(
			'editor' => array( self::EDIT_POST_SEO, self::EDIT_POST_ADVANCED ),
			'author' => array( self::EDIT_POST_SEO ),
		);

		foreach ( $grants as $role_name => $capabilities ) {
			$role = get_role( $role_name );

			if ( null === $role ) {
				continue;
			}

			foreach ( $capabilities as $capability ) {
				$role->add_cap( $capability );
			}
		}
	}

	/**
	 * Removes every plugin capability from every role of the current site.
	 *
	 * @since 1.0.0
	 *
	 * @return void
	 */
	public function remove_from_roles(): void {
		foreach ( wp_roles()->role_objects as $role ) {
			foreach ( self::all() as $capability ) {
				$role->remove_cap( $capability );
			}
		}
	}
}