GetConflictStatus

GetConflictStatus

public static ConflictStatus GetConflictStatus(string remoteAsString, string localAsString)
        {
            if (remoteAsString == localAsString)
                return ConflictStatus.AlreadyMerged;

            if(string.IsNullOrEmpty(remoteAsString))
                return ConflictStatus.AlreadyMerged;

            if (string.IsNullOrEmpty(remoteAsString) || string.IsNullOrEmpty(localAsString))
                return ConflictStatus.Update;

            var local = localAsString.ToChangeVector();
            var remote = remoteAsString.ToChangeVector();
            //any missing entries from a change vector are assumed to have zero value
            var localHasLargerEntries = false;
            var remoteHasLargerEntries = false;

            int numOfMatches = 0;
            for (int i = 0; i < remote.Length; i++)
            {
                bool found = false;
                for (int j = 0; j < local.Length; j++)
                {
                    if (remote[i].DbId == local[j].DbId)
                    {
                        found = true;
                        numOfMatches++;
                        if (remote[i].Etag > local[j].Etag)
                        {
                            remoteHasLargerEntries = true;
                        }
                        else if (remote[i].Etag < local[j].Etag)
                        {
                            localHasLargerEntries = true;
                        }
                        break;
                    }
                }
                if (found == false)
                {
                    remoteHasLargerEntries = true;
                }
            }
            if (numOfMatches < local.Length)
            {
                localHasLargerEntries = true;
            }

            if (remoteHasLargerEntries && localHasLargerEntries)
                return ConflictStatus.Conflict;
            
            if (remoteHasLargerEntries == false && localHasLargerEntries == false)
                return ConflictStatus.AlreadyMerged; // change vectors identical
            
            return remoteHasLargerEntries ? ConflictStatus.Update : ConflictStatus.AlreadyMerged;
        }