ChatServer.fs

module ChatServer

open System.Linq
open System.Collections.Generic

open Orleankka
open Orleankka.FSharp
open Messages

type ChatServer() = 
   inherit Actor<ServerMessage>()

   let _users = Dictionary<string, IObserverCollection>()

   let notifyClients msg = _users.Values |> Seq.iter(fun clients -> clients.Notify(msg))

   override this.Receive message = task {
      match message with
      
      | Join (userName, client) -> 
         match _users.TryGetValue(userName) with         
         | (true, clients) -> clients.Add(client)         
         | _ -> Notification(sprintf "User: %s connected..." userName) |> notifyClients
                let clients = ObserverCollection() :> IObserverCollection
                clients.Add(client)
                _users.Add(userName, clients)
                         
         return response("Hello and welcome to Orleankka chat example")
      
      | Say (userName, text) -> NewMessage(userName, text) |> notifyClients
                                return response()
      
      | Disconnect (userName, client) -> 
         match _users.TryGetValue(userName) with
         | (true, clients) -> if clients.Count() = 1 then _users.Remove(userName) |> ignore
                              else clients.Remove(client)
                              return response()
         | _ -> return response()
   }