<?php

/**

 * Session API: WP_User_Meta_Session_Tokens class

 *

 * @package WordPress

 * @subpackage Session

 * @since 4.7.0

 */

/**

 * Meta-based user sessions token manager.

 *

 * @since 4.0.0

 *

 * @see WP_Session_Tokens

 */

class WP_User_Meta_Session_Tokens extends WP_Session_Tokens {

	/**

	 * Retrieves all sessions of the user.

	 *

	 * @since 4.0.0

	 *

	 * @return array Sessions of the user.

	 */

	protected function get_sessions() {

		$sessions = get_user_meta( $this->user_id, 'session_tokens', true );

		if ( ! is_array( $sessions ) ) {

			return array();

		}

		$sessions = array_map( array( $this, 'prepare_session' ), $sessions );

		return array_filter( $sessions, array( $this, 'is_still_valid' ) );

	}

	/**

	 * Converts an expiration to an array of session information.

	 *

	 * @param mixed $session Session or expiration.

	 * @return array Session.

	 */

	protected function prepare_session( $session ) {

		if ( is_int( $session ) ) {

			return array( 'expiration' => $session );

		}

		return $session;

	}

	/**

	 * Retrieves a session based on its verifier (token hash).

	 *

	 * @since 4.0.0

	 *

	 * @param string $verifier Verifier for the session to retrieve.

	 * @return array|null The session, or null if it does not exist

	 */

	protected function get_session( $verifier ) {

		$sessions = $this->get_sessions();

		if ( isset( $sessions[ $verifier ] ) ) {

			return $sessions[ $verifier ];

		}

		return null;

	}

	/**

	 * Updates a session based on its verifier (token hash).

	 *

	 * @since 4.0.0

	 *

	 * @param string $verifier Verifier for the session to update.

	 * @param array  $session  Optional. Session. Omitting this argument destroys the session.

	 */

	protected function update_session( $verifier, $session = null ) {

		$sessions = $this->get_sessions();

		if ( $session ) {

			$sessions[ $verifier ] = $session;

		} else {

			unset( $sessions[ $verifier ] );

		}

		$this->update_sessions( $sessions );

	}

	/**

	 * Updates the user's sessions in the usermeta table.

	 *

	 * @since 4.0.0

	 *

	 * @param array $sessions Sessions.

	 */

	protected function update_sessions( $sessions ) {

		if ( $sessions ) {

			update_user_meta( $this->user_id, 'session_tokens', $sessions );

		} else {

			delete_user_meta( $this->user_id, 'session_tokens' );

		}

	}

	/**

	 * Destroys all sessions for this user, except the single session with the given verifier.

	 *

	 * @since 4.0.0

	 *

	 * @param string $verifier Verifier of the session to keep.

	 */

	protected function destroy_other_sessions( $verifier ) {

		$session = $this->get_session( $verifier );

		$this->update_sessions( array( $verifier => $session ) );

	}

	/**

	 * Destroys all session tokens for the user.

	 *

	 * @since 4.0.0

	 */

	protected function destroy_all_sessions() {

		$this->update_sessions( array() );

	}

	/**

	 * Destroys all sessions for all users.

	 *

	 * @since 4.0.0

	 */

	public static function drop_sessions() {

		delete_metadata( 'user', 0, 'session_tokens', false, true );

	}

}