Improving query for moving nodes from one list structure to another

[kkris1983]

We have following structure where User is starting point and nodes with numbers are labeled Invitation where its value specify their property id .

I am looking for a way to create a query which moves node from list pointed by VALID_INVITATIONS relationship to another list pointed by INVALID_INVITATIONS. Moved node should be set first in new list.

I came up with working solution but because of lack of knowledge and experience in Cypher I kindly ask you, the community for help and improvements for it. As you will see there is a lot of imperative code "hacks" (CASE WHEN) instead of declarative as Cypher supposed to be. I would appreciate for all hints and advices

MATCH (u:User)
MATCH (u)-[:VALID_INVITATIONS|PREVIOUS*]->(current:Invitation{ id:3 })

//find (current) node's predecessor which might pointing on it through VALID_INVITATIONS or PREVIOUS relationships
OPTIONAL MATCH (u)-[oldValidRel:VALID_INVITATIONS]->(current)
OPTIONAL MATCH (predecessor:Invitation)-[oldPredecessorRel:PREVIOUS]->(current)
//find (current) node's subsequent node
OPTIONAL MATCH (current)-[oldSubsequentRel:PREVIOUS]->(subsequent:Invitation)

//first we re-create connections in list pointed by VALID_INVITATION relationship for consistency
WITH *, CASE subsequent WHEN NULL THEN ELSE [1] END AS hasSubsequent

//if (current) node is connected to (u) User we replace VALID_INVITATIONS relationship
FOREACH(_ IN CASE oldValidRel WHEN NULL THEN ELSE [1] END |
DELETE oldValidRel

//if (subsequent) node exist then we need to re-link it
FOREACH(_ IN hasSubsequent |
    MERGE (u)-[:VALID_INVITATIONS]->(subsequent)
    DELETE oldSubsequentRel
)

)

//following condition should be XOR with the one above (only one must be executed)
//if (current) node has another Invitation node as predecessor in list
FOREACH(_ IN CASE oldPredecessorRel WHEN NULL THEN ELSE [1] END |
DELETE oldPredecessorRel

//if (subsequent) node exist then we need to re-link it
FOREACH(_ IN hasSubsequent |
    MERGE (predecessor)-[:PREVIOUS]->(subsequent)
    DELETE oldSubsequentRel
)

)

WITH u, current

//now it is time to move (current) node to beginning of the list pointed by INVALID_INVITATIONS relationship
MERGE (u)-[:INVALID_INVITATIONS]->(current)
WITH u, current
//find obsolete oldRel:INVALID_INVITATIONS relationship
MATCH (current)<-[:INVALID_INVITATIONS]-(u)-[oldRel:INVALID_INVITATIONS]->(oldInv)
DELETE oldRel
//link (current) with previously "first" node in INVALID_INVITATIONS list
MERGE (current)-[:PREVIOUS]->(oldInv)