Protocol Definition

We would need a formal definition what kind of messages can be sent between a client and the server.

So far we need this messages for sure:

For Setup:

Client connects -> Server responds ACK! if there are enough free slots, otherwise drop the connection.
Client defines personal info (e.g. Username, Rogue, Catcher) -> Server assigns unique number which can be used for a reconnect
Client sends its unique number -> Server reconnects client : should be possible during playing the game
Server announces that the game has begun if there are enough players registered.

For Game Playing:

Server informs all clients who is playing -> Open for Discussion: should a client send an ACK! or is it assumed that he got the message?
Client who is currently playing announces move -> Server validates move and sends feedback. Possible Feedback:
- The move was invalid (with reason: e.g. no such cards, unreachable, other players are on the position)
- It is not your turn
- You have found the rogue core
- Your move was valid and you have been moved together with a changed map and your current state
Server announces that rogue core has won -> No reaction required
Server announces that catchers found rogue core -> No reaction required.

After the game has finished:

Client disconnects -> Server clears the slot.

Discussion: Should the server offer to restart the game?

Messages by Client and Server

Client

Client Connect

This is not an explicit message

Personal Information

{ 
    "username": "string",
    "preferredColor":  "string",
    "wantsToBeRogue": true
}

Reconnect

{
    "reconnectId": 1234
}

Disconnect

This should be explicit to determine if the disconnecting player wants to reconnect later. To be discussed: Should it really be this way? Most clients probably won't send this message, but on the other hand, if a player completly disconnects, the game is probably over anyways.

For now: some temporal message

{
     "willComeBack": true
}

Client sends move

{
    "color": "green",
    "nodeId": 1234
}

Server

`ACK!` new client

Implicit ACK!. This is handled by the websocket and does not require an own message

Assign unique identification number

{
   "reconnectId": 1234,
   "clientId": 1234
}

reconnectId and clientId do not have to be distinct.

Start the game

After this message, no new player can connect.

{
   "newGame": true,
   "roguePlayer": 1234,
   "players": [1, 2, ...]
}

Inform clients of who is next

{
   "nextPlayer": 1234
}

Feedback about commited request

This needs more discussion regarding if this should be several different messages and what would be the best representation of an error in json.

{
   "invalid": true
}

The game has ended:

{
   "rogueVictory": true
}

Further possible messages

Text message which can be seen by other players
- includes different chat rooms for rogue, catchers and whole group
Announce where you wish to go next
Share your expectation where the rogue player should be
Lobby System for games

samuelpilz / core-catcher