/// <summary>
/// The method called when using the 'close chat' button. This is then used to inform the other
/// group members that the user has left the chat.
/// </summary>
/// <param name="chat">Chat with members</param>
/// <returns></returns>
public async Task LeaveGroup(Chat chat)
{
var connectionId = Context.ConnectionId;
var leavingUser = _users.Get(connectionId);
// TODO use OthersInGroup method to simplify frontend
await Clients.Group(chat.Id).SendAsync("leaveGroup", chat, leavingUser);
foreach (var user in chat.Users)
{
await Groups.RemoveFromGroupAsync(user.ConnectionId, chat.Id);
}
}