Implement the /reveal,/start endpoints as well as the "game-state" event

[empires-server] / server.js

diff --git a/server.js b/server.js
index ca7b844c5296b893ca114bc68433b8dd299a0ea5..b7a99a594267232fc2fcd457517dc2e914fc66f2 100644 (file)
--- a/server.js
+++ b/server.js
@@ -5,12 +5,42 @@ const body_parser = require("body-parser");
 const app = express();
 app.use(cors());
 
+const GameState = {
+  JOIN:    1,
+  REVEAL:  2,
+  CAPTURE: 3,
+  properties: {
+    1: {name: "join"},
+    2: {name: "reveal"},
+    3: {name: "capture"}
+  }
+};
+
+/**
+ * Shuffles array in place.
+ * @param {Array} a items An array containing the items.
+ */
+function shuffle(a) {
+  if (a === undefined)
+    return;
+
+  var j, x, i;
+  for (i = a.length - 1; i > 0; i--) {
+    j = Math.floor(Math.random() * (i + 1));
+    x = a[i];
+    a[i] = a[j];
+    a[j] = x;
+  }
+}
+
 class Game {
   constructor() {
     this._players = [];
+    this.characters_to_reveal = null;
     this.next_player_id = 1;
     this.clients = [];
     this.next_client_id = 1;
+    this.state = GameState.JOIN;
 
     /* Send a comment to every connected client every 15 seconds. */
     setInterval(() => {this.broadcast_string(":");}, 15000);
@@ -43,6 +73,39 @@ class Game {
     this.next_player_id = 1;
   }
 
+  reveal_next() {
+    if (this.reveal_index >= this.characters_to_reveal.length) {
+      clearInterval(this.reveal_interval);
+      this.broadcast_event("character-reveal", '{"character":""}');
+      return;
+    }
+    const character = this.characters_to_reveal[this.reveal_index];
+    this.reveal_index++;
+    const character_data = JSON.stringify({"character":character});
+    this.broadcast_event("character-reveal", character_data);
+  }
+
+  reveal() {
+    this.change_state(GameState.REVEAL);
+
+    if (this.characters_to_reveal === null) {
+      this.characters_to_reveal = [];
+      this.characters_to_reveal = this._players.reduce((characters, player) => {
+        characters.push(player.character);
+        return characters;
+      }, []);
+      shuffle(this.characters_to_reveal);
+    }
+
+    this.reveal_index = 0;
+
+    this.reveal_interval = setInterval(this.reveal_next.bind(this), 3000);
+  }
+
+  start() {
+    this.change_state(GameState.CAPTURE);
+  }
+
   capture(captor_id, captee_id) {
     /* TODO: Fix to fail on already-captured players (or to move the
      * captured player from an old captor to a new—need to clarify in
@@ -102,6 +165,34 @@ class Game {
   broadcast_event(type, data) {
     this.broadcast_string(`event: ${type}\ndata: ${data}\n`);
   }
+
+  game_state_event_data() {
+    var old_state_name;
+    if (this.old_state)
+      old_state_name = GameState.properties[this.old_state].name;
+    else
+      old_state_name = "none";
+    const new_state_name = GameState.properties[this.state].name;
+
+    return `{"old_state":"${old_state_name}","new_state":"${new_state_name}"}`;
+  }
+
+  /* Inform clients about a state change. */
+  broadcast_state_change() {
+    this.broadcast_event("game-state", this.game_state_event_data());
+  }
+
+  /* Change game state and broadcast the change to all clients. */
+  change_state(state) {
+    /* Do nothing if there is no actual change happening. */
+    if (state === this.state)
+      return;
+
+    this.old_state = this.state;
+    this.state = state;
+
+    this.broadcast_state_change();
+  }
 }
 
 const game = new Game();
@@ -126,6 +217,9 @@ function handle_events(request, response) {
     response.write(players_data);
   }
 
+  /* And we need to inform the client of the current game state. */
+  response.write("event: game-state\n" + "data: " + game.game_state_event_data() + "\n\n");
+
   /* Add this new client to our list of clients. */
   const id = game.add_client(response);
 
@@ -149,6 +243,16 @@ app.post('/deregister/:id', (request, response) => {
   response.send();
 });
 
+app.post('/reveal', (request, response) => {
+  game.reveal();
+  response.send();
+});
+
+app.post('/start', (request, response) => {
+  game.start();
+  response.send();
+});
+
 app.post('/reset', (request, response) => {
   game.remove_all_players();
   response.send();