1 const express = require("express");
2 const Game = require("./game.js");
4 const MAX_PROMPT_ITEMS = 20;
6 class Empathy extends Game {
13 players_answering: new Set(),
14 end_answers: new Set(),
17 players_judging: new Set(),
18 end_judging: new Set(),
22 this.next_prompt_id = 1;
23 this.equivalencies = {};
28 /* Before closing out the current round, we accumulate that score
29 * for each player into their runnning total. */
30 for (let score of this.state.scores.scores) {
31 const player = this.players.find(p => p.name === score.player);
33 player.score += score.score;
35 player.score = score.score;
37 /* And broadcast that new score out. */
38 this.broadcast_event('player-update', player.info_json());
41 /* Now that we're done with the active prompt, we remove it from
42 * the list of prompts and also remove any prompts that received
43 * no votes. This keeps the list of prompts clean.
45 const active_id = this.state.active_prompt.id;
47 this.state.prompts.filter(
48 p => p.id !== active_id && p.votes.length > 0
51 this.state.active_prompt = null;
52 this.state.players_answered = [];
53 this.state.players_answering = new Set();
54 this.state.end_answers = new Set();
55 this.state.ambiguities = 0;
56 this.state.players_judged = [];
57 this.state.players_judging = new Set();
58 this.state.end_judging = new Set();
59 this.state.scores = null;
62 this.equivalencies = {};
64 this.broadcast_event_object('game-state', this.state);
67 add_prompt(items, prompt_string) {
68 if (items > MAX_PROMPT_ITEMS)
71 message: `Maximum number of items is ${MAX_PROMPT_ITEMS}`
74 const prompt = new Prompt(this.next_prompt_id, items, prompt_string);
75 this.next_prompt_id++;
77 this.state.prompts.push(prompt);
79 this.broadcast_event_object('prompt', prompt);
87 /* Returns true if vote toggled, false for player or prompt not found */
88 toggle_vote(prompt_id, session_id) {
89 const player = this.players_by_session[session_id];
91 const prompt = this.state.prompts.find(p => p.id === prompt_id);
92 if (! prompt || ! player)
95 prompt.toggle_vote(player.name);
97 this.broadcast_event_object('prompt', prompt);
102 /* Returns true on success, false for prompt not found. */
104 const prompt = this.state.prompts.find(p => p.id === prompt_id);
108 /* Ignore any start request that comes in while a prompt is
109 * already being played. */
110 if (this.state.active_prompt)
113 this.state.active_prompt = prompt;
115 this.broadcast_event_object('start', prompt);
120 receive_answer(prompt_id, session_id, answers) {
121 const player = this.players_by_session[session_id];
123 return { valid: false, message: "Player not found" };
125 const prompt = this.state.prompts.find(p => p.id === prompt_id);
127 return { valid: false, message: "Prompt not found" };
129 if (prompt !== this.state.active_prompt)
130 return { valid: false, message: "Prompt no longer active" };
132 /* Save the complete answers for our own use later. */
138 /* And notify all players that this player has answered. */
139 this.state.players_answered.push(player.name);
140 this.broadcast_event_object('player-answered', player.name);
142 return { valid: true };
145 receive_answering(prompt_id, session_id) {
146 const player = this.players_by_session[session_id];
148 return { valid: false, message: "Player not found" };
150 const prompt = this.state.prompts.find(p => p.id === prompt_id);
152 return { valid: false, message: "Prompt not found" };
154 if (prompt !== this.state.active_prompt)
155 return { valid: false, message: "Prompt no longer active" };
157 /* Notify all players that this player is actively answering. */
158 this.state.players_answering.add(player.name);
159 this.broadcast_event_object('player-answering', player.name);
161 return { valid: true };
164 /* Returns true if vote toggled, false for player or prompt not found */
165 toggle_end_answers(prompt_id, session_id) {
166 const player = this.players_by_session[session_id];
168 const prompt = this.state.prompts.find(p => p.id === prompt_id);
169 if (! prompt || ! player)
172 if (this.state.end_answers.has(player.name)) {
173 this.state.end_answers.delete(player.name);
174 this.broadcast_event_object('unvote-end-answers', player.name);
176 this.state.end_answers.add(player.name);
177 this.broadcast_event_object('vote-end-answers', player.name);
186 for (let a of this.answers) {
187 for (let word of a.answers) {
188 const key = this.canonize(word);
189 word_map[key] = word;
193 this.state.ambiguities = Object.values(word_map).sort((a,b) => {
194 return a.toLowerCase().localeCompare(b.toLowerCase());
197 this.broadcast_event_object('ambiguities', this.state.ambiguities);
200 receive_judged(prompt_id, session_id, word_groups) {
201 const player = this.players_by_session[session_id];
203 return { valid: false, message: "Player not found" };
205 const prompt = this.state.prompts.find(p => p.id === prompt_id);
207 return { valid: false, message: "Prompt not found" };
209 if (prompt !== this.state.active_prompt)
210 return { valid: false, message: "Prompt no longer active" };
212 /* Each player submits some number of groups of answers that
213 * should be considered equivalent. The server expands that into
214 * the set of pair-wise equivalencies that are expressed. The
215 * reason for that is so that the server can determine which
216 * pair-wise equivalencies have majority support.
218 for (let group of word_groups) {
220 for (let i = 0; i < group.length - 1; i++) {
221 for (let j = i + 1; j < group.length; j++) {
222 let eq = [group[i], group[j]];
224 /* Put the two words into a reliable order so that we don't
225 * miss a pair of equivalent equivalencies just because they
226 * happen to be in the opposite order. */
227 if (eq[0].localeCompare(eq[1]) > 0) {
228 eq = [group[j], group[i]];
231 const key=`${this.canonize(eq[0])}:${this.canonize(eq[1])}`;
233 const exist = this.equivalencies[key];
237 this.equivalencies[key] = {
247 /* And notify all players this this player has judged. */
248 this.state.players_judged.push(player.name);
249 this.broadcast_event_object('player-judged', player.name);
251 return { valid: true };
254 receive_judging(prompt_id, session_id) {
255 const player = this.players_by_session[session_id];
257 return { valid: false, message: "Player not found" };
259 const prompt = this.state.prompts.find(p => p.id === prompt_id);
261 return { valid: false, message: "Prompt not found" };
263 if (prompt !== this.state.active_prompt)
264 return { valid: false, message: "Prompt no longer active" };
266 /* Notify all players this this player is actively judging. */
267 this.state.players_judging.add(player.name);
268 this.broadcast_event_object('player-judging', player.name);
270 return { valid: true };
273 /* Returns true if vote toggled, false for player or prompt not found */
274 toggle_end_judging(prompt_id, session_id) {
275 const player = this.players_by_session[session_id];
277 const prompt = this.state.prompts.find(p => p.id === prompt_id);
278 if (! prompt || ! player)
281 if (this.state.end_judging.has(player.name)) {
282 this.state.end_judging.delete(player.name);
283 this.broadcast_event_object('unvote-end-judging', player.name);
285 this.state.end_judging.add(player.name);
286 this.broadcast_event_object('vote-end-judging', player.name);
293 return word.toLowerCase();
297 const word_submitters = {};
299 /* Perform a (non-strict) majority ruling on equivalencies,
300 * dropping all that didn't get enough votes. */
301 const quorum = Math.floor((this.players.length + 1)/2);
302 const agreed_equivalencies = Object.values(this.equivalencies).filter(
303 eq => eq.count >= quorum);
305 /* And with that agreed set of equivalencies, construct the full
307 const word_maps = {};
309 for (let e of agreed_equivalencies) {
310 const word0_canon = this.canonize(e.words[0]);
311 const word1_canon = this.canonize(e.words[1]);
312 let group = word_maps[word0_canon];
314 group = word_maps[word1_canon];
316 group = { words: [], players: new Set()};
318 if (! word_maps[word0_canon]) {
319 word_maps[word0_canon] = group;
320 group.words.push(e.words[0]);
323 if (! word_maps[word1_canon]) {
324 word_maps[word1_canon] = group;
325 group.words.push(e.words[1]);
329 /* Now go through answers from each player and add the player
330 * to the set corresponding to each word group. */
331 for (let a of this.answers) {
332 for (let word of a.answers) {
333 const word_canon = this.canonize(word);
334 /* If there's no group yet, this is a singleton word. */
335 if (word_maps[word_canon]) {
336 word_maps[word_canon].players.add(a.player);
338 const group = { words: [word], players: new Set() };
339 group.players.add(a.player);
340 word_maps[word_canon] = group;
345 /* Now that we've assigned the players to these word maps, we now
346 * want to collapse the groups down to a single array of
349 * The difference between "word_maps" and "word_groups" is that
350 * the former has a property for every word that maps to a group,
351 * (so if you iterate over the keys you will see the same group
352 * multiple times). In contrast, iterating over"word_groups" will
353 * have you visit each group only once. */
354 const word_groups = Object.entries(word_maps).filter(
355 entry => entry[0] === this.canonize(entry[1].words[0]))
356 .map(entry => entry[1]);
358 /* Now, go through each word group and assign the scores out to
359 * the corresponding players.
361 * Note: We do this by going through the word groups, (as opposed
362 * to the list of words from the players again), specifically to
363 * avoid giving a player points for a wrod group twice (in the
364 * case where a player submits two different words that the group
365 * ends up judging as equivalent).
367 this.players.forEach(p => p.round_score = 0);
368 for (let group of word_groups) {
369 group.players.forEach(p => p.round_score += group.players.size);
372 const scores = this.players.map(p => {
379 scores.sort((a,b) => {
380 return b.score - a.score;
383 /* Put the word groups into a form the client can consume.
385 const words_submitted = word_groups.map(
388 word: group.words.join('/'),
389 players: Array.from(group.players).map(p => p.name)
394 words_submitted.sort((a,b) => {
395 return b.players.length - a.players.length;
398 /* Put this round's scores into the game state object so it will
399 * be sent to any new clients that join. */
400 this.state.scores = {
402 words: words_submitted
405 /* And broadcast the scores to all connected clients. */
406 this.broadcast_event_object('scores', this.state.scores);
410 Empathy.router = express.Router();
411 const router = Empathy.router;
414 constructor(id, items, prompt) {
417 this.prompt = prompt;
421 toggle_vote(player_name) {
422 if (this.votes.find(v => v === player_name))
423 this.votes = this.votes.filter(v => v !== player_name);
425 this.votes.push(player_name);
429 router.post('/prompts', (request, response) => {
430 const game = request.game;
432 const result = game.add_prompt(request.body.items, request.body.prompt);
434 response.json(result);
437 router.post('/vote/:prompt_id([0-9]+)', (request, response) => {
438 const game = request.game;
439 const prompt_id = parseInt(request.params.prompt_id, 10);
441 if (game.toggle_vote(prompt_id, request.session.id))
444 response.sendStatus(404);
447 router.post('/start/:prompt_id([0-9]+)', (request, response) => {
448 const game = request.game;
449 const prompt_id = parseInt(request.params.prompt_id, 10);
451 if (game.start(prompt_id))
454 response.sendStatus(404);
457 router.post('/answer/:prompt_id([0-9]+)', (request, response) => {
458 const game = request.game;
459 const prompt_id = parseInt(request.params.prompt_id, 10);
461 const result = game.receive_answer(prompt_id,
463 request.body.answers);
464 response.json(result);
467 router.post('/answering/:prompt_id([0-9]+)', (request, response) => {
468 const game = request.game;
469 const prompt_id = parseInt(request.params.prompt_id, 10);
471 const result = game.receive_answering(prompt_id,
473 response.json(result);
476 router.post('/end-answers/:prompt_id([0-9]+)', (request, response) => {
477 const game = request.game;
478 const prompt_id = parseInt(request.params.prompt_id, 10);
480 if (game.toggle_end_answers(prompt_id, request.session.id))
483 response.sendStatus(404);
485 if (game.state.end_answers.size > (game.state.players_answered.length / 2))
486 game.perform_judging();
489 router.post('/judged/:prompt_id([0-9]+)', (request, response) => {
490 const game = request.game;
491 const prompt_id = parseInt(request.params.prompt_id, 10);
493 const result = game.receive_judged(prompt_id,
495 request.body.word_groups);
496 response.json(result);
499 router.post('/judging/:prompt_id([0-9]+)', (request, response) => {
500 const game = request.game;
501 const prompt_id = parseInt(request.params.prompt_id, 10);
503 const result = game.receive_judging(prompt_id,
505 response.json(result);
508 router.post('/end-judging/:prompt_id([0-9]+)', (request, response) => {
509 const game = request.game;
510 const prompt_id = parseInt(request.params.prompt_id, 10);
512 if (game.toggle_end_judging(prompt_id, request.session.id))
515 response.sendStatus(404);
517 if (game.state.end_judging.size > (game.state.players_judged.length / 2))
518 game.compute_scores();
521 router.post('/reset', (request, response) => {
522 const game = request.game;
528 identifier: "empathy",
531 exports.Game = Empathy;