protocol

1. client connect to the server and send his name
   • '|' and spaces are not allowed
   • name must be unique
   • name cannot be empty string
2. In case of error, server send error message and disconnect, otherwise server send "SUCCESS".

Then client can send these commands to the server:

• "get clients"
  • server return list of clients names separated by '|'
    • the asking client is included in the list
• "get messages"
  • server return list messages directed to the client separated by '|'
    • the messages are in the format "[from_client] [msg]"
• "send to [name] [msg]"
  • send direct message to other client
  • client will get the message when it ask the server