class BBP_User_Engagements_Base {

	/**
	 * Type of strategy being used.
	 *
	 * @since 2.6.0 bbPress (r6737)
	 *
	 * @var string
	 */
	public $type = '';

	/**
	 * Add a user id to an object
	 *
	 * @since 2.6.0 bbPress (r6722)
	 *
	 * @param int    $object_id The object id
	 * @param int    $user_id   The user id
	 * @param string $meta_key  The relationship key
	 * @param string $meta_type The relationship type (usually 'post')
	 * @param bool   $unique    Whether meta key should be unique to the object
	 *
	 * @return bool Returns true on success, false on failure
	 */
	public function add_user_to_object( $object_id = 0, $user_id = 0, $meta_key = '', $meta_type = 'post', $unique = false ) {

	}

	/**
	 * Remove a user id from an object
	 *
	 * @since 2.6.0 bbPress (r6722)
	 *
	 * @param int    $object_id The object id
	 * @param int    $user_id   The user id
	 * @param string $meta_key  The relationship key
	 * @param string $meta_type The relationship type (usually 'post')
	 *
	 * @return bool Returns true on success, false on failure
	 */
	public function remove_user_from_object( $object_id = 0, $user_id = 0, $meta_key = '', $meta_type = 'post' ) {

	}

	/**
	 * Remove a user id from all objects
	 *
	 * @since 2.6.0 bbPress (r6722)
	 *
	 * @param int    $user_id   The user id
	 * @param string $meta_key  The relationship key
	 * @param string $meta_type The relationship type (usually 'post')
	 *
	 * @return bool Returns true on success, false on failure
	 */
	public function remove_user_from_all_objects( $user_id = 0, $meta_key = '', $meta_type = 'post' ) {

	}

	/**
	 * Remove an object from all users
	 *
	 * @since 2.6.0 bbPress (r6722)
	 *
	 * @param int    $object_id The object id
	 * @param int    $user_id   The user id
	 * @param string $meta_key  The relationship key
	 * @param string $meta_type The relationship type (usually 'post')
	 *
	 * @return bool Returns true on success, false on failure
	 */
	public function remove_object_from_all_users( $object_id = 0, $meta_key = '', $meta_type = 'post' ) {

	}

	/**
	 * Remove all users from all objects
	 *
	 * @since 2.6.0 bbPress (r6722)
	 *
	 * @param string $meta_key  The relationship key
	 * @param string $meta_type The relationship type (usually 'post')
	 *
	 * @return bool Returns true on success, false on failure
	 */
	public function remove_all_users_from_all_objects( $meta_key = '', $meta_type = 'post' ) {

	}

	/**
	 * Get users of an object
	 *
	 * @since 2.6.0 bbPress (r6722)
	 *
	 * @param int    $object_id The object id
	 * @param string $meta_key  The key used to index this relationship
	 * @param string $meta_type The type of meta to look in
	 *
	 * @return array Returns ids of users
	 */
	public function get_users_for_object( $object_id = 0, $meta_key = '', $meta_type = 'post' ) {

	}

	/**
	 * Get the part of the query responsible for JOINing objects to relationships.
	 *
	 * @since 2.6.0 bbPress (r6737)
	 *
	 * @param array  $args
	 * @param string $meta_key
	 * @param string $meta_type
	 *
	 * @return array
	 */
	public function get_query( $args = array(), $context_key = '', $meta_key = '', $meta_type = 'post' ) {

	}
}