1 const express = require("express");
2 const cors = require("cors");
3 const body_parser = require("body-parser");
4 const path = require("path");
21 * Shuffles array in place.
22 * @param {Array} a items An array containing the items.
29 for (i = a.length - 1; i > 0; i--) {
30 j = Math.floor(Math.random() * (i + 1));
40 this.characters_to_reveal = null;
41 this.next_player_id = 1;
43 this.next_client_id = 1;
44 this.state = GameState.JOIN;
46 /* Send a comment to every connected client every 15 seconds. */
47 setInterval(() => {this.broadcast_string(":");}, 15000);
50 add_player(name, character) {
51 const new_player = {id: this.next_player_id,
56 this._players.push(new_player);
57 this.next_player_id++;
58 /* The syntax here is using an anonymous function to create a new
59 object from new_player with just the subset of fields that we
61 const player_data = JSON.stringify((({id, name}) => ({id, name}))(new_player));
62 this.broadcast_event("player-join", player_data);
66 const index = this._players.findIndex(player => player.id === id);
67 this._players.splice(index, 1);
69 this.broadcast_event("player-leave", `{"id": ${id}}`);
74 this.characters_to_reveal = null;
75 this.next_player_id = 1;
77 this.change_state(GameState.JOIN);
79 this.broadcast_event("players", "{}");
83 /* Don't try to reveal anything if we aren't in the reveal state. */
84 if (this.state != GameState.REVEAL) {
85 clearInterval(this.reveal_interval);
89 if (this.reveal_index >= this.characters_to_reveal.length) {
90 clearInterval(this.reveal_interval);
91 this.broadcast_event("character-reveal", '{"character":""}');
94 const character = this.characters_to_reveal[this.reveal_index];
96 const character_data = JSON.stringify({"character":character});
97 this.broadcast_event("character-reveal", character_data);
101 this.change_state(GameState.REVEAL);
103 if (this.characters_to_reveal === null) {
104 this.characters_to_reveal = [];
105 this.characters_to_reveal = this._players.reduce((characters, player) => {
106 characters.push(player.character);
109 shuffle(this.characters_to_reveal);
112 this.reveal_index = 0;
114 this.reveal_interval = setInterval(this.reveal_next.bind(this), 3000);
118 this.change_state(GameState.CAPTURE);
121 capture(captor_id, captee_id) {
122 /* TODO: Fix to fail on already-captured players (or to move the
123 * captured player from an old captor to a new—need to clarify in
124 * the API specification which we want here. */
125 let captor = this._players.find(player => player.id === captor_id);
126 captor.captures.push(captee_id);
128 this.broadcast_event("capture", `{"captor": ${captor_id}, "captee": ${captee_id}}`);
131 liberate(captee_id) {
132 let captor = this._players.find(player => player.captures.includes(captee_id));
133 captor.captures.splice(captor.captures.indexOf(captee_id), 1);
137 for (const player of this._players) {
138 player.captures = [];
143 return this._players.map(player => player.character);
147 return this._players.map(player => ({id: player.id, captures: player.captures}));
151 return this._players.map(player => ({id: player.id, name: player.name }));
154 add_client(response) {
155 const id = this.next_client_id;
156 this.clients.push({id: id,
157 response: response});
158 this.next_client_id++;
164 this.clients = this.clients.filter(client => client.id !== id);
167 /* Send a string to all clients */
168 broadcast_string(str) {
169 this.clients.forEach(client => client.response.write(str + '\n'));
172 /* Send an event to all clients.
174 * An event has both a declared type and a separate data block.
175 * It also ends with two newlines (to mark the end of the event).
177 broadcast_event(type, data) {
178 this.broadcast_string(`event: ${type}\ndata: ${data}\n`);
181 game_state_event_data(old_state, new_state) {
184 old_state_name = GameState.properties[old_state].name;
186 old_state_name = "none";
187 const new_state_name = GameState.properties[new_state].name;
189 return `{"old_state":"${old_state_name}","new_state":"${new_state_name}"}`;
192 /* Inform clients about a state change. */
193 broadcast_state_change() {
194 const event_data = this.game_state_event_data(this.old_state, this.state);
195 this.broadcast_event("game-state", event_data);
198 /* Change game state and broadcast the change to all clients. */
199 change_state(state) {
200 /* Do nothing if there is no actual change happening. */
201 if (state === this.state)
204 this.old_state = this.state;
207 this.broadcast_state_change();
211 app.use(body_parser.urlencoded({ extended: false }));
212 app.use(body_parser.json());
214 function handle_events(request, response) {
215 const game = request.game;
216 /* These headers will keep the connection open so we can stream events. */
218 "Content-type": "text/event-stream",
219 "Connection": "keep-alive",
220 "Cache-Control": "no-cache"
222 response.writeHead(200, headers);
224 /* Now that a client has connected, first we need to stream all of
225 * the existing players (if any). */
226 if (game._players.length > 0) {
227 const players_json = JSON.stringify(game.players);
228 const players_data = `event: players\ndata: ${players_json}\n\n`;
229 response.write(players_data);
232 /* And we need to inform the client of the current game state.
234 * In fact, we need to cycle through each state transition from the
235 * beginning so the client can see each.
237 var old_state = null;
238 for (var state = GameState.JOIN; state <= game.state; state++) {
239 var event_data = game.game_state_event_data(old_state, state);
240 response.write("event: game-state\n" + "data: " + event_data + "\n\n");
244 /* Add this new client to our list of clients. */
245 const id = game.add_client(response);
247 /* And queue up cleanup to be triggered on client close. */
248 request.on('close', () => {
249 game.remove_client(id);
253 app.get('/', (request, response) => {
254 response.sendFile(path.join(__dirname, './game.html'));
257 app.post('/register', (request, response) => {
258 const game = request.game;
259 game.add_player(request.body.name, request.body.character);
263 app.post('/deregister/:id', (request, response) => {
264 const game = request.game;
265 game.remove_player(parseInt(request.params.id));
269 app.post('/reveal', (request, response) => {
270 const game = request.game;
275 app.post('/start', (request, response) => {
276 const game = request.game;
281 app.post('/reset', (request, response) => {
282 const game = request.game;
287 app.post('/capture/:captor/:captee', (request, response) => {
288 const game = request.game;
289 game.capture(parseInt(request.params.captor), parseInt(request.params.captee));
293 app.post('/liberate/:id', (request, response) => {
294 const game = request.game;
295 game.liberate(parseInt(request.params.id));
299 app.post('/restart', (request, response) => {
300 const game = request.game;
301 game.restart(parseInt(request.params.id));
305 app.get('/characters', (request, response) => {
306 const game = request.game;
307 response.send(game.characters);
310 app.get('/empires', (request, response) => {
311 const game = request.game;
312 response.send(game.empires);
315 app.get('/players', (request, response) => {
316 const game = request.game;
317 response.send(game.players);
320 app.get('/events', handle_events);