webclient/js/Games.js

import Messaging;
import player from Room;
import Save;
import Session;
import Table;
import Time;

var metadata = Table.make(function(o) {return o.value.date;});
metadata.insertAll(Save.get('games.metadata') || {});
initMessageHandlers();

return {
	metadata: metadata,
	proposal: proposal
};

function makeMetadata(state) {
	var sessionKey = Session.getKey();
	return Time.timestamp({
		vs: player(state.public.nextPlayer[sessionKey]),
		yourTurn: state.public.playing == sessionKey
	});
}

function proposal(playerID, yourTurn) {
	metadata.insert(
		playerID,
		Time.timestamp({vs: player(playerID), yourTurn: yourTurn})
	);
}

function pushState(gameID, state) {
	var latestPath = "games.state." + gameID + ".latest";
	var formerPath = "games.state." + gameID + ".former";
	var former = Save.get(latestPath);
	if(former != undefined) {
		Save.set(formerPath, former);
	}
	Save.set(latestPath, state);
}

function compare(gameCoordinatesA, gameCoordinatesB) {
  if(gameCoordinatesA.month < gameCoordinatesB.month) {
    return -1;
  } else if(gameCoordinatesA.month > gameCoordinatesB.month) {
    return 1;
  } else if(gameCoordinatesA.turn < gameCoordinatesB.turn) {
    return -1;
  } else if(gameCoordinatesA.turn > gameCoordinatesB.turn) {
    return 1;
  } else {
    return 0;
  }
}

function initMessageHandlers() {
	Messaging.addEventListener(["Game"], function(o) {
		var gameID = o.state.public.coordinates.gameID;
		var metadata = makeMetadata(o.state);
		pushState(gameID, o.state);
		Save.set("games.metadata." + gameID, metadata);
		metadata.insert(gameID, metadata);
	});

  Messaging.addEventListener(["Relay", "Sync"], function(o) {
    var gameID = o.message.latestKnown.gameID;
    var latestKnownHere = Save.get("games.state." + gameID + ".latest");
    switch(compare(latestKnownHere, o.message.latestKnown)) {
      case -1: Messaging.send({tag: "Yield", onGameID: gameID});
      case 1: Messaging.send({tag: "Sync", latestKnown: latestKnownHere});
    }
  });

  Messaging.addEventListener(["Relay", "Yield"], function(o) {
    var gameID = o.message.latestKnown.gameID;
    var latestKnownHere = Save.get("games.message." + gameID + ".latest");
    if(o.from == latestKnownHere.public.nextPlayer[Session.getKey()]) {
      Messaging.send({tag: "Share", gameSave: latestKnownHere});
    }
  });
}