GitUI.CommandsDialogs.FormBrowse.getNextIdx C# (CSharp) Method

        private int getNextIdx(int curIdx, int maxIdx, bool searchBackward)
        {
            if (searchBackward)
            {
                if (curIdx == 0)
                {
                    curIdx = maxIdx;
                }
                else
                {
                    curIdx--;
                }
            }
            else
            {
                if (curIdx == maxIdx)
                {
                    curIdx = 0;
                }
                else
                {
                    curIdx++;
                }
            }
            return curIdx;
        }