ReportActor.cs

public class ReportActor : ReceiveActor
{
    private Dictionary<string, long> _articleTimeSpent;
    private Dictionary<string, int> _articleViews;

    public ReportActor()
    {
        _articleTimeSpent = new Dictionary<string, long>();
        _articleViews = new Dictionary<string, int>();

        Receive<ReportMessage>(message => ReceivedReportMessage(message));
        Receive<StartedReadingMessage>(message => IncreaseViewCounter(message));
    }

    private void ReceivedReportMessage(ReportMessage message)
    {
        long time;
        if (_articleTimeSpent.TryGetValue(message.Article, out time))
            time += message.Milliseconds;
        else
            _articleTimeSpent.Add(message.Article, message.Milliseconds);

        Console.WriteLine("******************************************************");
        Console.WriteLine("User {0} was reading article {1} for {2} milliseconds.", message.User, message.Article, message.Milliseconds);
        Console.WriteLine("Aricle {0} was read for {1} milliseconds in total.", message.Article, _articleTimeSpent[message.Article]);
        Console.WriteLine("******************************************************\n");

    }

    private void IncreaseViewCounter(StartedReadingMessage message)
    {
        int count;
        if (_articleViews.TryGetValue(message.Article, out count))
            _articleViews[message.Article]++;
        else
            _articleViews.Add(message.Article, 1);

        Console.WriteLine("******************************************************");
        Console.WriteLine("Article {0} has {1} views", message.Article, _articleViews[message.Article]);
        Console.WriteLine("******************************************************\n");
    }
}