/// <summary>
/// Subscribes to notifications from ClientBoardStateManager to get updates.
/// </summary>
/// <param name="listener">The subscriber. </param>
/// <param name="identifier">The identifier of the subscriber. </param>
public void Subscribe(IClientBoardStateListener listener, string identifier)
{
// Cleaning current state since new state will be called
_mapIdToBoardShape = null;
_mapIdToQueueElement = null;
_priorityQueue = null;
_redoStack = null;
_undoStack = null;
GC.Collect();
// Re-initializing state and adding subscriber
InitializeDataStructures();
_clients.Add(identifier, listener);
try
{
// Creating BoardServerShape object and requesting communicator
Trace.WriteLine("ClientBoardStateManager.Subscribe: Sending fetch state request to communicator.");
BoardServerShape boardServerShape = new(null, Operation.FETCH_STATE, _currentUserId);
_clientBoardCommunicator.Send(boardServerShape);
Trace.WriteLine("ClientBoardStateManager.Subscribe: Fetch state request sent to communicator.");
}
catch (Exception e)
{
Trace.WriteLine("ClientBoardStateManager.Subscribe: Exception occurred.");
Trace.WriteLine(e.Message);
}
}
/// <summary>
/// Initializes the data structures which are maintaining the state.
/// </summary>
/// <param name="initializeUndoRedo">Initialize undo-redo stacks or not. By default it is true.</param>
private void InitializeDataStructures(bool initializeUndoRedo = true)
{
_mapIdToBoardShape = new Dictionary <string, BoardShape>();
_mapIdToQueueElement = new Dictionary <string, QueueElement>();
_priorityQueue = new BoardPriorityQueue();
if (initializeUndoRedo)
{
_redoStack = new BoardStack(_undoRedoCapacity);
_undoStack = new BoardStack(_undoRedoCapacity);
}
}
