1 const express = require("express");
2 const Game = require("./game.js");
4 const engine_name = "empires";
6 const router = express.Router();
20 * Shuffles array in place.
21 * @param {Array} a items An array containing the items.
28 for (i = a.length - 1; i > 0; i--) {
29 j = Math.floor(Math.random() * (i + 1));
36 class Empires extends Game {
39 this._spectators = [];
40 this.next_spectator_id = 1;
42 this.next_player_id = 1;
43 this.characters_to_reveal = null;
44 this.state = GameState.JOIN;
46 /* Send a comment to every connected client every 15 seconds. */
47 setInterval(() => {this.broadcast_string(":");}, 15000);
50 add_spectator(name, session_id) {
51 /* Don't add another spectator that matches an existing session. */
52 const existing = this._spectators.findIndex(
53 spectator => spectator.session_id === session_id);
57 const new_spectator = {id: this.next_spectator_id,
59 session_id: session_id
61 this._spectators.push(new_spectator);
62 this.next_spectator_id++;
63 this.broadcast_event("spectator-join", JSON.stringify(new_spectator));
65 return new_spectator.id;
68 remove_spectator(id) {
69 const index = this._spectators.findIndex(spectator => spectator.id === id);
70 this._spectators.splice(index, 1);
72 this.broadcast_event("spectator-leave", `{"id": ${id}}`);
75 add_player(name, character) {
76 const new_player = {id: this.next_player_id,
81 this._players.push(new_player);
82 this.next_player_id++;
83 /* The syntax here is using an anonymous function to create a new
84 object from new_player with just the subset of fields that we
86 const player_data = JSON.stringify((({id, name}) => ({id, name}))(new_player));
87 this.broadcast_event("player-join", player_data);
93 const index = this._players.findIndex(player => player.id === id);
94 this._players.splice(index, 1);
96 this.broadcast_event("player-leave", `{"id": ${id}}`);
101 this.characters_to_reveal = null;
102 this.next_player_id = 1;
104 this.change_state(GameState.JOIN);
106 this.broadcast_event("spectators", "{}");
107 this.broadcast_event("players", "{}");
111 /* Don't try to reveal anything if we aren't in the reveal state. */
112 if (this.state != GameState.REVEAL) {
113 clearInterval(this.reveal_interval);
117 if (this.reveal_index >= this.characters_to_reveal.length) {
118 clearInterval(this.reveal_interval);
119 this.broadcast_event("character-reveal", '{"character":""}');
122 const character = this.characters_to_reveal[this.reveal_index];
124 const character_data = JSON.stringify({"character":character});
125 this.broadcast_event("character-reveal", character_data);
129 this.change_state(GameState.REVEAL);
131 if (this.characters_to_reveal === null) {
132 this.characters_to_reveal = [];
133 this.characters_to_reveal = this._players.reduce((characters, player) => {
134 characters.push(player.character);
137 shuffle(this.characters_to_reveal);
140 this.reveal_index = 0;
142 this.reveal_interval = setInterval(this.reveal_next.bind(this), 3000);
146 this.change_state(GameState.CAPTURE);
149 capture(captor_id, captee_id) {
150 /* TODO: Fix to fail on already-captured players (or to move the
151 * captured player from an old captor to a new—need to clarify in
152 * the API specification which we want here. */
153 let captor = this._players.find(player => player.id === captor_id);
154 captor.captures.push(captee_id);
156 this.broadcast_event("capture", `{"captor": ${captor_id}, "captee": ${captee_id}}`);
159 liberate(captee_id) {
160 let captor = this._players.find(player => player.captures.includes(captee_id));
161 captor.captures.splice(captor.captures.indexOf(captee_id), 1);
165 for (const player of this._players) {
166 player.captures = [];
171 return this._players.map(player => player.character);
175 return this._players.map(player => ({id: player.id, captures: player.captures}));
179 /* We return only "id" and "name" here (specifically not session_id!). */
180 return this._spectators.map(spectator => ({
187 return this._players.map(player => ({id: player.id, name: player.name }));
190 game_state_event_data(old_state, new_state) {
193 old_state_name = GameState.properties[old_state].name;
195 old_state_name = "none";
196 const new_state_name = GameState.properties[new_state].name;
198 return `{"old_state":"${old_state_name}","new_state":"${new_state_name}"}`;
201 /* Inform clients about a state change. */
202 broadcast_state_change() {
203 const event_data = this.game_state_event_data(this.old_state, this.state);
204 this.broadcast_event("game-state", event_data);
207 /* Change game state and broadcast the change to all clients. */
208 change_state(state) {
209 /* Do nothing if there is no actual change happening. */
210 if (state === this.state)
213 this.old_state = this.state;
216 this.broadcast_state_change();
219 handle_events(request, response) {
221 super.handle_events(request, response);
223 /* Now that a client has connected, first we need to stream all of
224 * the existing spectators and players (if any). */
225 if (this._spectators.length > 0) {
226 const spectators_json = JSON.stringify(this.spectators);
227 const spectators_data = `event: spectators\ndata: ${spectators_json}\n\n`;
228 response.write(spectators_data);
231 if (this._players.length > 0) {
232 const players_json = JSON.stringify(this.players);
233 const players_data = `event: players\ndata: ${players_json}\n\n`;
234 response.write(players_data);
237 /* And we need to inform the client of the current game state.
239 * In fact, we need to cycle through each state transition from the
240 * beginning so the client can see each.
242 var old_state = null;
243 for (var state = GameState.JOIN; state <= this.state; state++) {
244 var event_data = this.game_state_event_data(old_state, state);
245 response.write("event: game-state\n" + "data: " + event_data + "\n\n");
252 router.get('/', (request, response) => {
253 if (! request.session.nickname)
254 response.render('choose-nickname.html', { game_name: "Empires" });
256 response.render('empires-game.html');
259 router.post('/spectator', (request, response) => {
260 const game = request.game;
261 var name = request.session.nickname;
263 /* If the request includes a name, that overrides the session nickname. */
264 if (request.body.name)
265 name = request.body.name;
267 const id = game.add_spectator(name, request.session.id);
268 response.send(JSON.stringify(id));
271 router.delete('/spectator/:id', (request, response) => {
272 const game = request.game;
273 game.remove_spectator(parseInt(request.params.id));
277 router.post('/register', (request, response) => {
278 const game = request.game;
279 var name = request.session.nickname;;
281 /* If the request includes a name, that overrides the session nickname. */
282 if (request.body.name)
283 name = request.body.name;
285 const player = game.add_player(name, request.body.character);
286 response.send(JSON.stringify(player.id));
289 router.post('/deregister/:id', (request, response) => {
290 const game = request.game;
291 game.remove_player(parseInt(request.params.id));
295 router.post('/reveal', (request, response) => {
296 const game = request.game;
301 router.post('/start', (request, response) => {
302 const game = request.game;
307 router.post('/reset', (request, response) => {
308 const game = request.game;
313 router.post('/capture/:captor/:captee', (request, response) => {
314 const game = request.game;
315 game.capture(parseInt(request.params.captor), parseInt(request.params.captee));
319 router.post('/liberate/:id', (request, response) => {
320 const game = request.game;
321 game.liberate(parseInt(request.params.id));
325 router.post('/restart', (request, response) => {
326 const game = request.game;
327 game.restart(parseInt(request.params.id));
331 router.get('/characters', (request, response) => {
332 const game = request.game;
333 response.send(game.characters);
336 router.get('/empires', (request, response) => {
337 const game = request.game;
338 response.send(game.empires);
341 router.get('/spectators', (request, response) => {
342 const game = request.game;
343 response.send(game.spectators);
346 router.get('/players', (request, response) => {
347 const game = request.game;
348 response.send(game.players);
351 router.get('/events', (request, response) => {
352 const game = request.game;
353 game.handle_events(request, response);
356 exports.router = router;
357 exports.name = engine_name;
358 exports.Game = Empires;