-const express = require("express")
+const express = require("express");
+const cors = require("cors");
const body_parser = require("body-parser");
const app = express();
+app.use(cors());
class Game {
constructor() {
- this.players = [];
+ this._players = [];
this.next_player_id = 1;
+ this.clients = [];
+ this.next_client_id = 1;
+
+ /* Send a comment to every connected client every 15 seconds. */
+ setInterval(() => {this.broadcast_string(":");}, 15000);
}
add_player(name, character) {
- this.players.push({id: this.next_player_id,
+ const new_player = {id: this.next_player_id,
name: name,
- character: character})
+ character: character,
+ captures: [],
+ };
+ this._players.push(new_player);
this.next_player_id++;
+ /* The syntax here is using an anonymous function to create a new
+ object from new_player with just the subset of fields that we
+ want. */
+ const player_string = JSON.stringify((({id, name}) => ({id, name}))(new_player));
+ this.broadcast_event("player-register", player_string);
+ }
+
+ remove_player(id) {
+ const index = this._players.findIndex(player => player.id === id);
+ this._players.splice(index, 1);
+
+ this.broadcast_event("player-deregister", `{"id": ${id}}`);
+ }
+
+ remove_all_players() {
+ this._players = [];
+ this.next_player_id = 1;
+ }
+
+ 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
+ * the API specification which we want here. */
+ let captor = this._players.find(player => player.id === captor_id);
+ captor.captures.push(captee_id);
+
+ this.broadcast_event("capture", `{"captor": ${captor_id}, "captee": ${captee_id}}`);
+ }
+
+ liberate(captee_id) {
+ let captor = this._players.find(player => player.captures.includes(captee_id));
+ captor.captures.splice(captor.captures.indexOf(captee_id), 1);
+ }
+
+ restart() {
+ for (const player of this._players) {
+ player.captures = [];
+ }
+ }
+
+ get characters() {
+ return this._players.map(player => player.character);
+ }
+
+ get empires() {
+ return this._players.map(player => ({id: player.id, captures: player.captures}));
+ }
+
+ get players() {
+ return this._players.map(player => ({id: player.id, name: player.name }));
+ }
+
+ add_client(response) {
+ const id = this.next_client_id;
+ this.clients.push({id: id,
+ response: response});
+ this.next_client_id++;
+
+ return id;
+ }
+
+ remove_client(id) {
+ this.clients = this.clients.filter(client => client.id !== id);
+ }
+
+ /* Send a string to all clients */
+ broadcast_string(str) {
+ this.clients.forEach(client => client.response.write(str + '\n'));
+ }
+
+ /* Send an event to all clients.
+ *
+ * An event has both a declared type and a separate data block.
+ * It also ends with two newlines (to mark the end of the event).
+ */
+ broadcast_event(type, data) {
+ this.broadcast_string(`event: ${type}\ndata: ${data}\n`);
}
}
-game = new Game();
+const game = new Game();
app.use(body_parser.urlencoded({ extended: false }));
app.use(body_parser.json());
-app.get('/', function (requses, response) {
+function handle_events(request, response) {
+ /* These headers will keep the connection open so we can stream events. */
+ const headers = {
+ "Content-type": "text/event-stream",
+ "Connection": "keep-alive",
+ "Cache-Control": "no-cache"
+ };
+ response.writeHead(200, headers);
+
+ /* Now that a client has connected, first we need to stream all of
+ * the existing players (if any). */
+ if (game._players.length > 0) {
+ const players_json = JSON.stringify(game.players);
+ const players_data = `event: players\ndata: ${players_json}\n\n`;
+ response.write(players_data);
+ }
+
+ /* Add this new client to our list of clients. */
+ const id = game.add_client(response);
+
+ /* And queue up cleanup to be triggered on client close. */
+ request.on('close', () => {
+ game.remove_client(id);
+ });
+}
+
+app.get('/', (request, response) => {
response.send('Hello World!');
});
-app.get('/players', function (request, response) {
- response.send(game.players);
+app.post('/register', (request, response) => {
+ game.add_player(request.body.name, request.body.character);
+ response.send();
});
-app.post('/register', function (request, response) {
- game.add_player(request.body.name, request.body.character);
+app.post('/deregister/:id', (request, response) => {
+ game.remove_player(parseInt(request.params.id));
response.send();
});
+app.post('/reset', (request, response) => {
+ game.remove_all_players();
+ response.send();
+});
+
+app.post('/capture/:captor/:captee', (request, response) => {
+ game.capture(parseInt(request.params.captor), parseInt(request.params.captee));
+ response.send();
+});
+
+app.post('/liberate/:id', (request, response) => {
+ game.liberate(parseInt(request.params.id));
+ response.send();
+});
+
+app.post('/restart', (request, response) => {
+ game.restart(parseInt(request.params.id));
+ response.send();
+});
+
+app.get('/characters', (request, response) => {
+ response.send(game.characters);
+});
+
+app.get('/empires', (request, response) => {
+ response.send(game.empires);
+});
+
+app.get('/players', (request, response) => {
+ response.send(game.players);
+});
+
+app.get('/events', handle_events);
+
app.listen(3000, function () {
- console.log('Example app listening on port 3000!');
+ console.log('Empires server listening on localhost:3000');
});