1 const express = require("express");
2 const cors = require("cors");
3 const body_parser = require("body-parser");
4 const path = require("path");
8 app.use(body_parser.urlencoded({ extended: false }));
9 app.use(body_parser.json());
23 * Shuffles array in place.
24 * @param {Array} a items An array containing the items.
31 for (i = a.length - 1; i > 0; i--) {
32 j = Math.floor(Math.random() * (i + 1));
42 this.characters_to_reveal = null;
43 this.next_player_id = 1;
45 this.next_client_id = 1;
46 this.state = GameState.JOIN;
48 /* Send a comment to every connected client every 15 seconds. */
49 setInterval(() => {this.broadcast_string(":");}, 15000);
52 add_player(name, character) {
53 const new_player = {id: this.next_player_id,
58 this._players.push(new_player);
59 this.next_player_id++;
60 /* The syntax here is using an anonymous function to create a new
61 object from new_player with just the subset of fields that we
63 const player_data = JSON.stringify((({id, name}) => ({id, name}))(new_player));
64 this.broadcast_event("player-join", player_data);
68 const index = this._players.findIndex(player => player.id === id);
69 this._players.splice(index, 1);
71 this.broadcast_event("player-leave", `{"id": ${id}}`);
76 this.characters_to_reveal = null;
77 this.next_player_id = 1;
79 this.change_state(GameState.JOIN);
81 this.broadcast_event("players", "{}");
85 /* Don't try to reveal anything if we aren't in the reveal state. */
86 if (this.state != GameState.REVEAL) {
87 clearInterval(this.reveal_interval);
91 if (this.reveal_index >= this.characters_to_reveal.length) {
92 clearInterval(this.reveal_interval);
93 this.broadcast_event("character-reveal", '{"character":""}');
96 const character = this.characters_to_reveal[this.reveal_index];
98 const character_data = JSON.stringify({"character":character});
99 this.broadcast_event("character-reveal", character_data);
103 this.change_state(GameState.REVEAL);
105 if (this.characters_to_reveal === null) {
106 this.characters_to_reveal = [];
107 this.characters_to_reveal = this._players.reduce((characters, player) => {
108 characters.push(player.character);
111 shuffle(this.characters_to_reveal);
114 this.reveal_index = 0;
116 this.reveal_interval = setInterval(this.reveal_next.bind(this), 3000);
120 this.change_state(GameState.CAPTURE);
123 capture(captor_id, captee_id) {
124 /* TODO: Fix to fail on already-captured players (or to move the
125 * captured player from an old captor to a new—need to clarify in
126 * the API specification which we want here. */
127 let captor = this._players.find(player => player.id === captor_id);
128 captor.captures.push(captee_id);
130 this.broadcast_event("capture", `{"captor": ${captor_id}, "captee": ${captee_id}}`);
133 liberate(captee_id) {
134 let captor = this._players.find(player => player.captures.includes(captee_id));
135 captor.captures.splice(captor.captures.indexOf(captee_id), 1);
139 for (const player of this._players) {
140 player.captures = [];
145 return this._players.map(player => player.character);
149 return this._players.map(player => ({id: player.id, captures: player.captures}));
153 return this._players.map(player => ({id: player.id, name: player.name }));
156 add_client(response) {
157 const id = this.next_client_id;
158 this.clients.push({id: id,
159 response: response});
160 this.next_client_id++;
166 this.clients = this.clients.filter(client => client.id !== id);
169 /* Send a string to all clients */
170 broadcast_string(str) {
171 this.clients.forEach(client => client.response.write(str + '\n'));
174 /* Send an event to all clients.
176 * An event has both a declared type and a separate data block.
177 * It also ends with two newlines (to mark the end of the event).
179 broadcast_event(type, data) {
180 this.broadcast_string(`event: ${type}\ndata: ${data}\n`);
183 game_state_event_data(old_state, new_state) {
186 old_state_name = GameState.properties[old_state].name;
188 old_state_name = "none";
189 const new_state_name = GameState.properties[new_state].name;
191 return `{"old_state":"${old_state_name}","new_state":"${new_state_name}"}`;
194 /* Inform clients about a state change. */
195 broadcast_state_change() {
196 const event_data = this.game_state_event_data(this.old_state, this.state);
197 this.broadcast_event("game-state", event_data);
200 /* Change game state and broadcast the change to all clients. */
201 change_state(state) {
202 /* Do nothing if there is no actual change happening. */
203 if (state === this.state)
206 this.old_state = this.state;
209 this.broadcast_state_change();
213 function handle_events(request, response) {
214 const game = request.game;
215 /* These headers will keep the connection open so we can stream events. */
217 "Content-type": "text/event-stream",
218 "Connection": "keep-alive",
219 "Cache-Control": "no-cache"
221 response.writeHead(200, headers);
223 /* Now that a client has connected, first we need to stream all of
224 * the existing players (if any). */
225 if (game._players.length > 0) {
226 const players_json = JSON.stringify(game.players);
227 const players_data = `event: players\ndata: ${players_json}\n\n`;
228 response.write(players_data);
231 /* And we need to inform the client of the current game state.
233 * In fact, we need to cycle through each state transition from the
234 * beginning so the client can see each.
236 var old_state = null;
237 for (var state = GameState.JOIN; state <= game.state; state++) {
238 var event_data = game.game_state_event_data(old_state, state);
239 response.write("event: game-state\n" + "data: " + event_data + "\n\n");
243 /* Add this new client to our list of clients. */
244 const id = game.add_client(response);
246 /* And queue up cleanup to be triggered on client close. */
247 request.on('close', () => {
248 game.remove_client(id);
252 app.get('/', (request, response) => {
253 response.sendFile(path.join(__dirname, './game.html'));
256 app.post('/register', (request, response) => {
257 const game = request.game;
258 game.add_player(request.body.name, request.body.character);
262 app.post('/deregister/:id', (request, response) => {
263 const game = request.game;
264 game.remove_player(parseInt(request.params.id));
268 app.post('/reveal', (request, response) => {
269 const game = request.game;
274 app.post('/start', (request, response) => {
275 const game = request.game;
280 app.post('/reset', (request, response) => {
281 const game = request.game;
286 app.post('/capture/:captor/:captee', (request, response) => {
287 const game = request.game;
288 game.capture(parseInt(request.params.captor), parseInt(request.params.captee));
292 app.post('/liberate/:id', (request, response) => {
293 const game = request.game;
294 game.liberate(parseInt(request.params.id));
298 app.post('/restart', (request, response) => {
299 const game = request.game;
300 game.restart(parseInt(request.params.id));
304 app.get('/characters', (request, response) => {
305 const game = request.game;
306 response.send(game.characters);
309 app.get('/empires', (request, response) => {
310 const game = request.game;
311 response.send(game.empires);
314 app.get('/players', (request, response) => {
315 const game = request.game;
316 response.send(game.players);
319 app.get('/events', handle_events);