feat: #20 use time to answer as tiebreaker in scoring

backend/src/main/kotlin/org/quizmania/game/api/commands.kt

@@ -40,7 +40,8 @@ data class AnswerQuestionCommand(
     override val gameId: UUID,
     val gameQuestionId: UUID,
     val username: String,
-    val answer: String
+    val answer: String,
+    val answerTimestamp: Instant,
 ): GameCommand
 
 data class OverrideAnswerCommand(

backend/src/main/kotlin/org/quizmania/game/api/events.kt

@@ -66,7 +66,8 @@ data class QuestionAnsweredEvent(
   override val gameQuestionId: GameQuestionId,
   val gamePlayerId: GamePlayerId,
   val playerAnswerId: UUID,
-  val answer: String
+  val answer: String,
+  val timeToAnswer: Long,
 ) : GameQuestionEvent
 
 data class QuestionAnswerOverriddenEvent(

backend/src/main/kotlin/org/quizmania/game/command/application/domain/GameAggregate.kt

@@ -141,7 +141,7 @@ internal class GameAggregate() {
 
     val player = players.getByUsername(command.username)
     val gameQuestion = askedQuestions.getById(command.gameQuestionId)
-    gameQuestion.answer(player.gamePlayerId, command.answer)
+    gameQuestion.answer(player.gamePlayerId, command.answer, command.answerTimestamp)
 
     // after QuestionAnsweredEvent is applied, the player-answer is actually in the list
     if (players.size == gameQuestion.numAnswers()) {
@@ -278,6 +278,7 @@ internal class GameAggregate() {
         playerAnswers = mutableListOf(),
         playerBuzzes = mutableListOf(),
         isModerated = moderatorUsername != null,
+        questionAskedTimestamp = event.questionTimestamp
       )
     )
   }

backend/src/main/kotlin/org/quizmania/game/command/application/domain/GameQuestion.kt

@@ -1,5 +1,6 @@
 package org.quizmania.game.command.application.domain
 
+import org.axonframework.eventhandling.Timestamp
 import org.axonframework.eventsourcing.EventSourcingHandler
 import org.axonframework.modelling.command.AggregateLifecycle
 import org.axonframework.modelling.command.EntityId
@@ -19,6 +20,7 @@ data class GameQuestion(
   val number: GameQuestionNumber,
   val question: Question,
   val questionMode: GameQuestionMode,
+  val questionAskedTimestamp: Instant,
   private var playerAnswers: MutableList<PlayerAnswer> = mutableListOf(),
   private var playerBuzzes: MutableList<PlayerBuzz> = mutableListOf(),
   private var currentBuzzWinner: GamePlayerId? = null,
@@ -72,7 +74,7 @@ data class GameQuestion(
     }
   }
 
-  fun answer(gamePlayerId: GamePlayerId, answer: String) {
+  fun answer(gamePlayerId: GamePlayerId, answer: String, answerTimestamp: Instant) {
     if (this.questionMode == GameQuestionMode.BUZZER) {
       throw QuestionInBuzzerModeProblem(this.gameId, this.id)
     }
@@ -86,7 +88,8 @@ data class GameQuestion(
         gameQuestionId = id,
         gamePlayerId = gamePlayerId,
         playerAnswerId = UUID.randomUUID(),
-        answer = answer
+        answer = answer,
+        answerTimestamp.toEpochMilli() - this.questionAskedTimestamp.toEpochMilli()
       )
     )
   }
@@ -178,7 +181,8 @@ data class GameQuestion(
           gameQuestionId = id,
           gamePlayerId = this.currentBuzzWinner!!,
           playerAnswerId = UUID.randomUUID(),
-          answer = question.correctAnswer
+          answer = question.correctAnswer,
+          0
         )
       )
       AggregateLifecycle.apply(
@@ -196,7 +200,8 @@ data class GameQuestion(
           gameQuestionId = id,
           gamePlayerId = this.currentBuzzWinner!!,
           playerAnswerId = UUID.randomUUID(),
-          answer = "" // some empty wrong answer - TODO better concept?
+          answer = "", // some empty wrong answer - TODO better concept?
+          0L
         )
       )
 

backend/src/main/kotlin/org/quizmania/rest/adapter/in/rest/GameCommandController.kt

@@ -107,7 +107,8 @@ class GameCommandController(
         gameId = gameId,
         gameQuestionId = answer.gameQuestionId,
         username = username,
-        answer = answer.answer
+        answer = answer.answer,
+        answer.answerTimestamp
       )
     )
     return ResponseEntity.ok().build()
@@ -196,7 +197,8 @@ data class NewGameDto(
 
 data class AnswerDto(
   val gameQuestionId: UUID,
-  val answer: String
+  val answer: String,
+  val answerTimestamp: Instant
 )
 
 data class BuzzDto(

e2e/codecept.conf.ts

@@ -14,7 +14,7 @@ export const config: CodeceptJS.MainConfig = {
   helpers: {
     Playwright: {
       browser: 'chromium',
-      url: 'http://localhost:8080',
+      url: 'http://localhost:5173',
       show: true
     }
   },

e2e/test/multiplayer.tsx

@@ -60,7 +60,7 @@ Scenario('multiplayer_moderated', ({I, loginPage, lobbyPage, gameRoomPage}) => {
   I.waitForText(username2)
   I.waitForText(username3)
 
-  I.wait(5)
+  I.wait(5000)
 
   gameRoomPage.startGame()
 

frontend/src/domain/GameModel.tsx

@@ -36,6 +36,7 @@ export class Game {
   readonly moderator: string | undefined;
   readonly status: GameStatus;
   readonly players: Player[];
+  readonly numQuestions: number = 0;
   readonly currentQuestion: GameQuestion | undefined;
 
   constructor(event: GameCreatedEvent) {
@@ -120,6 +121,7 @@ export class Game {
 
   public onQuestionAsked(event: QuestionAskedEvent): Game {
     return this.copyWith({
+      numQuestions: this.numQuestions + 1,
       currentQuestion:
         new GameQuestion(event)
     })
@@ -136,7 +138,22 @@ export class Game {
   }
 
   public onQuestionAnswered(event: QuestionAnsweredEvent): Game {
-    return this.updateQuestion(event.gameQuestionId, question => question.onQuestionAnswered(event))
+    const game = this.updateQuestion(event.gameQuestionId, question => question.onQuestionAnswered(event))
+
+    const newPlayers = game.players.map(player => {
+      if (event.gamePlayerId === player.id) {
+        return {
+          ...player,
+          totalAnswerTime: player.totalAnswerTime + event.timeToAnswer
+        }
+      } else {
+        return player
+      }
+    })
+
+    return game.copyWith({
+      players: newPlayers
+    })
   }
 
   public onQuestionAnswerOverridden(event: QuestionAnswerOverriddenEvent): Game {
@@ -182,6 +199,11 @@ export class Game {
   public findPlayerPoints(gamePlayerId: string): number {
     return this.players.find(player => player.id === gamePlayerId)?.points ?? 0
   }
+
+  public findAverageAnswerTime(gamePlayerId: string): number {
+    const totalAnswerTime = this.players.find(player => player.id === gamePlayerId)?.totalAnswerTime ?? 0
+    return totalAnswerTime / this.numQuestions
+  }
 }
 
 export class GameQuestion {
@@ -227,7 +249,7 @@ export class GameQuestion {
     return this.copyWith({
       answers: [
         ...this.answers.filter(answer => answer.gamePlayerId != event.gamePlayerId),
-        new Answer(event)
+        new Answer({...event, timeToAnswer: 0})
       ]
     })
   }
@@ -287,6 +309,7 @@ export class Player {
   readonly id: string;
   readonly name: string;
   readonly points: number = 0;
+  readonly totalAnswerTime: number = 0;
 
   constructor(id: string, name: string) {
     this.id = id

frontend/src/domain/__tests__/GameModel.test.tsx

@@ -166,6 +166,7 @@ function questionAnswered(id: string, playerId: string, answerId: string, answer
     gamePlayerId: playerId,
     playerAnswerId: answerId,
     answer: answer,
+    timeToAnswer: 0,
   }
 }
 

frontend/src/pages/GameSelectionPage.tsx

@@ -90,7 +90,7 @@ const GameSelectionPage = () => {
       console.log('no username set, redirect to login');
       navigate('/login');
     }
-  }, [username]);
+  }, [username, navigate]);
 
   useEffect(() => {
     gameOverviewService.searchOpenGames(setGames)

frontend/src/pages/game/gameroom/Scoreboard.tsx

@@ -8,13 +8,13 @@ import useWindowDimensions from "../../../hooks/useWindowDimensions.tsx";
 import {useUsername} from "../../../hooks/useUsername.ts";
 
 
-const comparePlayersByPointsAndName = function (p1: Player, p2: Player): number {
+const comparePlayersByPointsAndAnswerTime = function (p1: Player, p2: Player): number {
   if (p1.points < p2.points)
     return 1
   if (p1.points > p2.points)
     return -1
 
-  return p1.name.localeCompare(p2.name)
+  return p1.totalAnswerTime - p2.totalAnswerTime
 }
 
 export type ScoreboardProps = {
@@ -45,7 +45,7 @@ const ScoreboardPage = ({game, page, pageSize}: ScoreboardPageProps) => {
         </TableRow>
       </TableHead>
       <TableBody>
-        {[...game.players].sort(comparePlayersByPointsAndName)
+        {[...game.players].sort(comparePlayersByPointsAndAnswerTime)
           .slice(first, last)
           .map((player, index) => {
             let icon
@@ -90,10 +90,11 @@ const ScoreboardPage = ({game, page, pageSize}: ScoreboardPageProps) => {
           <TableCell></TableCell>
           <TableCell>Username</TableCell>
           <TableCell align="right">Points</TableCell>
+          <TableCell align="right">ø</TableCell>
         </TableRow>
       </TableHead>
       <TableBody>
-        {[...game.players].sort(comparePlayersByPointsAndName)
+        {[...game.players].sort(comparePlayersByPointsAndAnswerTime)
           .slice(first, last)
           .map((player, index) => {
             const fontWeight = player.name === username ? 'bold' : 'normal'
@@ -106,6 +107,7 @@ const ScoreboardPage = ({game, page, pageSize}: ScoreboardPageProps) => {
                   </Typography>
                 </TableCell>
                 <TableCell width={10} align="right" sx={{fontWeight: fontWeight}}>{player.points}</TableCell>
+                <TableCell width={10} align="right" sx={{fontWeight: fontWeight}}>{Math.round(game.findAverageAnswerTime(player.id)/10)/100}s</TableCell>
               </TableRow>
             )
           })}

frontend/src/services/GameCommandService.tsx

@@ -95,7 +95,13 @@ export class GameCommandService {
   }
 
   public async answerQuestion(answer: AnswerQuestionCommand) {
-    await this.genericPost('/api/game/' + answer.gameId + '/answer-question', JSON.stringify(answer))
+    await this.genericPost('/api/game/' + answer.gameId + '/answer-question',
+      JSON.stringify({
+        gameId: answer.gameId,
+        gameQuestionId: answer.gameQuestionId,
+        answer: answer.answer,
+        answerTimestamp: getCurrentServerTime().toISOString()
+      }))
   }
 
   public async buzzQuestion(buzz: BuzzQuestionCommand) {

frontend/src/services/GameEventTypes.tsx

@@ -73,6 +73,7 @@ export type QuestionAnsweredEvent = {
   gamePlayerId: string,
   playerAnswerId: string,
   answer: string,
+  timeToAnswer: number
 }
 
 export type QuestionAnswerOverriddenEvent = {

frontend/src/services/GameRepository.tsx

@@ -37,6 +37,7 @@ export class GameRepository {
 
   client?: Client;
   currentGameState: Game | undefined
+  lastReceivedSeqNo: number = -1
 
   public subscribeToGame(gameId: string, gameEventHandler: GameEventHandler) {
     if (this.client == null) {
@@ -66,12 +67,18 @@ export class GameRepository {
       this.client.deactivate()
       this.client = undefined
       this.currentGameState = undefined
+      this.lastReceivedSeqNo = -1
     } else {
       console.log("Client not active")
     }
   }
 
   private handleEvent(wrappedEvent: GameEventWrapper, gameEventHandler: GameEventHandler) {
+    if (wrappedEvent.sequenceNumber <= this.lastReceivedSeqNo) {
+      console.log("Ignoring event with SeqNo ", wrappedEvent.sequenceNumber)
+      return
+    }
+    this.lastReceivedSeqNo = wrappedEvent.sequenceNumber
     this.currentGameState = this.currentGameState!.onGameEvent(wrappedEvent.payload, wrappedEvent.eventType)
     gameEventHandler.onGameEvent(wrappedEvent.payload, wrappedEvent.eventType, this.currentGameState)
   }