/// <summary>
/// When the method is called with no arguments, just return the view
/// When argument logOn is true, a user logged on
/// When argument logOff is true, a user closed their browser or navigated away (log off)
/// When argument chatMessage is specified, the user typed something in the chat
/// </summary>
public ActionResult Index(string user,bool? logOn, bool? logOff, string chatMessage)
{
try
{
if (chatModel == null) chatModel = new ChatModel();
//trim chat history if needed
if (chatModel.ChatHistory.Count > 100)
chatModel.ChatHistory.RemoveRange(0, 90);
if (!Request.IsAjaxRequest())
{
//first time loading
return View(chatModel);
}
else if (logOn != null && (bool)logOn)
{
//check if nickname already exists
if (chatModel.Users.FirstOrDefault(u => u.NickName == user) != null)
{
throw new Exception("This nickname already exists");
}
else if (chatModel.Users.Count > 10)
{
throw new Exception("The room is full!");
}
else
{
#region create new user and add to lobby
chatModel.Users.Add( new ChatModel.ChatUser()
{
NickName = user,
LoggedOnTime = DateTime.Now,
LastPing = DateTime.Now
});
//inform lobby of new user
chatModel.ChatHistory.Add(new ChatModel.ChatMessage()
{
Message = "User '" + user + "' logged on.",
When = DateTime.Now
});
#endregion
}
return PartialView("Lobby", chatModel);
}
else if (logOff != null && (bool)logOff)
{
LogOffUser( chatModel.Users.FirstOrDefault( u=>u.NickName==user) );
return PartialView("Lobby", chatModel);
}
else
{
ChatModel.ChatUser currentUser = chatModel.Users.FirstOrDefault(u => u.NickName == user);
//remember each user's last ping time
currentUser.LastPing = DateTime.Now;
#region remove inactive users
List<ChatModel.ChatUser> removeThese = new List<ChatModel.ChatUser>();
foreach (Models.ChatModel.ChatUser usr in chatModel.Users)
{
TimeSpan span = DateTime.Now - usr.LastPing;
if (span.TotalSeconds > 15)
removeThese.Add(usr);
}
foreach (ChatModel.ChatUser usr in removeThese)
{
LogOffUser(usr);
}
#endregion
#region if there is a new message, append it to the chat
if (!string.IsNullOrEmpty(chatMessage))
{
chatModel.ChatHistory.Add(new ChatModel.ChatMessage()
{
ByUser = currentUser,
Message = chatMessage,
When = DateTime.Now
});
}
#endregion
return PartialView("ChatHistory", chatModel);
}
}
catch (Exception ex)
{
//return error to AJAX function
Response.StatusCode = 500;
return Content(ex.Message);
}
}
/// <summary>
/// Remove this user from the lobby and inform others that he logged off
/// </summary>
/// <param name="user"></param>
public void LogOffUser(ChatModel.ChatUser user)
{
chatModel.Users.Remove(user);
chatModel.ChatHistory.Add(new ChatModel.ChatMessage()
{
Message = "User '" + user.NickName + "' logged off.",
When = DateTime.Now
});
}
