<?php
/**
 * Menu item visibility by login state and user role.
 *
 * @package advance-menu-manager
 */

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

class DSAMM_Menu_Item_Visibility {

	const META_VISIBILITY       = '_amm_menu_visibility';
	const META_VISIBILITY_ROLES = '_amm_menu_visibility_roles';

	const VISIBILITY_EVERYONE   = 'everyone';
	const VISIBILITY_LOGGED_OUT = 'logged_out';
	const VISIBILITY_LOGGED_IN  = 'logged_in';

	/**
	 * Register frontend filter.
	 */
	public static function init() {
		add_filter( 'wp_nav_menu_objects', array( __CLASS__, 'filter_nav_menu_items' ), 10, 2 );
	}

	/**
	 * Get visibility mode for a menu item.
	 *
	 * @param int $menu_item_id Menu item post ID.
	 * @return string
	 */
	public static function get_visibility( $menu_item_id ) {
		$visibility = get_post_meta( (int) $menu_item_id, self::META_VISIBILITY, true );

		if ( empty( $visibility ) ) {
			return self::VISIBILITY_EVERYONE;
		}

		$allowed = array(
			self::VISIBILITY_EVERYONE,
			self::VISIBILITY_LOGGED_OUT,
			self::VISIBILITY_LOGGED_IN,
		);

		return in_array( $visibility, $allowed, true ) ? $visibility : self::VISIBILITY_EVERYONE;
	}

	/**
	 * Get allowed roles for a menu item.
	 *
	 * @param int $menu_item_id Menu item post ID.
	 * @return array
	 */
	public static function get_visibility_roles( $menu_item_id ) {
		$roles = get_post_meta( (int) $menu_item_id, self::META_VISIBILITY_ROLES, true );

		if ( empty( $roles ) || ! is_array( $roles ) ) {
			return array();
		}

		return array_map( 'sanitize_key', $roles );
	}

	/**
	 * Save visibility settings for a menu item.
	 *
	 * @param int    $menu_item_id Menu item post ID.
	 * @param string $visibility   Visibility mode.
	 * @param array  $roles        Role slugs.
	 */
	public static function save_visibility( $menu_item_id, $visibility, $roles = array() ) {
		$menu_item_id = (int) $menu_item_id;

		if ( $menu_item_id <= 0 ) {
			return;
		}

		$allowed = array(
			self::VISIBILITY_EVERYONE,
			self::VISIBILITY_LOGGED_OUT,
			self::VISIBILITY_LOGGED_IN,
		);

		if ( ! in_array( $visibility, $allowed, true ) ) {
			$visibility = self::VISIBILITY_EVERYONE;
		}

		update_post_meta( $menu_item_id, self::META_VISIBILITY, $visibility );

		if ( self::VISIBILITY_LOGGED_IN === $visibility && ! empty( $roles ) ) {
			$wp_roles    = wp_roles();
			$valid_roles = array();

			foreach ( $roles as $role ) {
				$role = sanitize_key( $role );
				if ( isset( $wp_roles->roles[ $role ] ) ) {
					$valid_roles[] = $role;
				}
			}

			update_post_meta( $menu_item_id, self::META_VISIBILITY_ROLES, $valid_roles );
		} else {
			delete_post_meta( $menu_item_id, self::META_VISIBILITY_ROLES );
		}
	}

	/**
	 * Copy visibility settings from one menu item to another.
	 *
	 * @param int $from_item_id Source menu item ID.
	 * @param int $to_item_id   Target menu item ID.
	 */
	public static function copy_visibility( $from_item_id, $to_item_id ) {
		self::save_visibility(
			$to_item_id,
			self::get_visibility( $from_item_id ),
			self::get_visibility_roles( $from_item_id )
		);
	}

	/**
	 * Attach visibility data to menu item objects before revision storage.
	 *
	 * @param array $menu_items Menu item objects.
	 * @return array
	 */
	public static function attach_visibility_to_menu_items( $menu_items ) {
		if ( empty( $menu_items ) || ! is_array( $menu_items ) ) {
			return $menu_items;
		}

		foreach ( $menu_items as $index => $item ) {
			$item_id = isset( $item->db_id ) ? (int) $item->db_id : 0;

			if ( $item_id <= 0 ) {
				continue;
			}

			$menu_items[ $index ]->amm_visibility       = self::get_visibility( $item_id );
			$menu_items[ $index ]->amm_visibility_roles = self::get_visibility_roles( $item_id );
		}

		return $menu_items;
	}

	/**
	 * Restore visibility settings from a revision menu item object.
	 *
	 * @param int    $menu_item_id Menu item post ID.
	 * @param object $item         Menu item object from revision.
	 */
	public static function restore_visibility_from_item_object( $menu_item_id, $item ) {
		$visibility = self::VISIBILITY_EVERYONE;
		$roles      = array();

		if ( isset( $item->amm_visibility ) && ! empty( $item->amm_visibility ) ) {
			$visibility = $item->amm_visibility;
		}

		if ( isset( $item->amm_visibility_roles ) && is_array( $item->amm_visibility_roles ) ) {
			$roles = $item->amm_visibility_roles;
		}

		self::save_visibility( $menu_item_id, $visibility, $roles );
	}

	/**
	 * Save visibility from POST request for a menu item.
	 *
	 * @param int $menu_item_id Menu item post ID.
	 */
	public static function save_from_request( $menu_item_id ) {
		$menu_item_id = (int) $menu_item_id;

		// phpcs:disable WordPress.Security.NonceVerification.Missing -- Nonce already verified in caller dsamm_save_existing_menu().
		if ( $menu_item_id <= 0 || empty( $_POST['menu-item-visibility'] ) || ! is_array( $_POST['menu-item-visibility'] ) ) {
			return;
		}

		$visibility_values = wp_unslash( $_POST['menu-item-visibility'] ); // phpcs:ignore WordPress.Security.ValidatedSanitizedInput.InputNotSanitized

		if ( ! isset( $visibility_values[ $menu_item_id ] ) ) {
			return;
		}

		$visibility = sanitize_text_field( $visibility_values[ $menu_item_id ] );
		$roles      = array();

		if (
			self::VISIBILITY_LOGGED_IN === $visibility
			&& ! empty( $_POST['menu-item-visibility-roles'][ $menu_item_id ] )
			&& is_array( $_POST['menu-item-visibility-roles'][ $menu_item_id ] )
		) {
			$roles = array_map( 'sanitize_key', wp_unslash( $_POST['menu-item-visibility-roles'][ $menu_item_id ] ) );
		}
		// phpcs:enable WordPress.Security.NonceVerification.Missing

		self::save_visibility( $menu_item_id, $visibility, $roles );
	}

	/**
	 * Determine if the current visitor can see a menu item.
	 *
	 * @param string $visibility Visibility mode.
	 * @param array  $roles      Allowed role slugs.
	 * @return bool
	 */
	public static function user_can_see_item( $visibility, $roles = array() ) {
		if ( self::VISIBILITY_EVERYONE === $visibility ) {
			return true;
		}

		if ( self::VISIBILITY_LOGGED_OUT === $visibility ) {
			return ! is_user_logged_in();
		}

		if ( self::VISIBILITY_LOGGED_IN === $visibility ) {
			if ( ! is_user_logged_in() ) {
				return false;
			}

			if ( empty( $roles ) ) {
				return true;
			}

			$user = wp_get_current_user();

			foreach ( $roles as $role ) {
				if ( in_array( $role, (array) $user->roles, true ) ) {
					return true;
				}
			}

			return false;
		}

		return true;
	}

	/**
	 * Filter nav menu items on the frontend.
	 *
	 * @param array $items Menu items.
	 * @param object $args Menu arguments.
	 * @return array
	 */
	public static function filter_nav_menu_items( $items, $args ) {
		if ( empty( $items ) || ! is_array( $items ) ) {
			return $items;
		}

		if ( is_admin() && ! wp_doing_ajax() ) {
			return $items;
		}

		$hidden_ids = array();

		foreach ( $items as $item ) {
			if ( in_array( (int) $item->menu_item_parent, $hidden_ids, true ) ) {
				$hidden_ids[] = (int) $item->ID;
				continue;
			}

			$visibility = self::get_visibility( $item->ID );
			$roles      = self::get_visibility_roles( $item->ID );

			if ( ! self::user_can_see_item( $visibility, $roles ) ) {
				$hidden_ids[] = (int) $item->ID;
			}
		}

		$changed = true;
		while ( $changed ) {
			$changed = false;

			foreach ( $items as $item ) {
				$item_id   = (int) $item->ID;
				$parent_id = (int) $item->menu_item_parent;

				if ( ! in_array( $item_id, $hidden_ids, true ) && in_array( $parent_id, $hidden_ids, true ) ) {
					$hidden_ids[] = $item_id;
					$changed      = true;
				}
			}
		}

		$hidden_ids = array_unique( $hidden_ids );

		return array_values(
			array_filter(
				$items,
				function( $item ) use ( $hidden_ids ) {
					return ! in_array( (int) $item->ID, $hidden_ids, true );
				}
			)
		);
	}

	/**
	 * Render visibility fields for a menu item.
	 *
	 * @param int   $menu_item_id Menu item db/post ID.
	 * @param array $args         Field arguments.
	 */
	public static function render_fields( $menu_item_id, $args = array() ) {
		$defaults = array(
			'readonly'    => false,
			'locked_attr' => '',
		);
		$args = wp_parse_args( $args, $defaults );

		$menu_item_id = (int) $menu_item_id;
		$visibility   = self::get_visibility( $menu_item_id );
		$roles        = self::get_visibility_roles( $menu_item_id );
		$wp_roles     = wp_roles();
		$role_names   = is_object( $wp_roles ) ? $wp_roles->get_names() : array();
		$show_roles   = ( self::VISIBILITY_LOGGED_IN === $visibility );
		$readonly     = ! empty( $args['readonly'] );
		$locked_attr  = ! empty( $args['locked_attr'] ) ? $args['locked_attr'] : '';
		$disabled     = ( $readonly || ! empty( $locked_attr ) ) ? 'disabled="disabled"' : '';
		?>
		<div class="field-amm-visibility description description-wide">
			<p class="field-amm-visibility-select">
				<label for="edit-menu-item-visibility-<?php echo esc_attr( $menu_item_id ); ?>">
					<?php esc_html_e( 'Who can see this link?', 'advance-menu-manager' ); ?><br />
					<select
						id="edit-menu-item-visibility-<?php echo esc_attr( $menu_item_id ); ?>"
						class="widefat amm-menu-visibility-select"
						name="menu-item-visibility[<?php echo esc_attr( $menu_item_id ); ?>]"
						<?php echo esc_attr( $disabled ); ?>
					>
						<option value="<?php echo esc_attr( self::VISIBILITY_EVERYONE ); ?>" <?php selected( $visibility, self::VISIBILITY_EVERYONE ); ?>>
							<?php esc_html_e( 'Everyone', 'advance-menu-manager' ); ?>
						</option>
						<option value="<?php echo esc_attr( self::VISIBILITY_LOGGED_OUT ); ?>" <?php selected( $visibility, self::VISIBILITY_LOGGED_OUT ); ?>>
							<?php esc_html_e( 'Logged Out Users', 'advance-menu-manager' ); ?>
						</option>
						<option value="<?php echo esc_attr( self::VISIBILITY_LOGGED_IN ); ?>" <?php selected( $visibility, self::VISIBILITY_LOGGED_IN ); ?>>
							<?php esc_html_e( 'Logged In Users', 'advance-menu-manager' ); ?>
						</option>
					</select>
				</label>
			</p>
			<div class="amm-menu-visibility-roles" style="<?php echo esc_attr( $show_roles ? '' : 'display:none;' ); ?>">
				<p class="description">
					<strong><?php esc_html_e( 'Choose which roles can see this link', 'advance-menu-manager' ); ?></strong>
				</p>
				<ul class="amm-menu-visibility-role-list">
					<?php foreach ( $role_names as $role_slug => $role_label ) : ?>
						<li>
							<label for="edit-menu-item-visibility-role-<?php echo esc_attr( $menu_item_id . '-' . $role_slug ); ?>">
								<input
									type="checkbox"
									id="edit-menu-item-visibility-role-<?php echo esc_attr( $menu_item_id . '-' . $role_slug ); ?>"
									name="menu-item-visibility-roles[<?php echo esc_attr( $menu_item_id ); ?>][]"
									value="<?php echo esc_attr( $role_slug ); ?>"
									<?php checked( in_array( $role_slug, $roles, true ) ); ?>
									<?php echo esc_attr( $disabled ); ?>
								/>
								<?php echo esc_html( translate_user_role( $role_label ) ); ?>
							</label>
						</li>
					<?php endforeach; ?>
				</ul>
			</div>
		</div>
		<?php
	}
}

DSAMM_Menu_Item_Visibility::init();