chore(release): 4.4.9 [skip ci]

## [4.4.9](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.4.8...v4.4.9) (2025-10-17)

### Bug Fixes

* **complement-race:** reduce initial momentum from 50 to 10 to prevent train sailing past first station ([5f146b0](5f146b0daf))

CHANGELOG.md

@@ -1,3 +1,64 @@
+## [4.4.9](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.4.8...v4.4.9) (2025-10-17)
+
+
+### Bug Fixes
+
+* **complement-race:** reduce initial momentum from 50 to 10 to prevent train sailing past first station ([5f146b0](https://github.com/antialias/soroban-abacus-flashcards/commit/5f146b0daf74d54e1c7b9a57d3a2f37e73849ff2))
+
+## [4.4.8](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.4.7...v4.4.8) (2025-10-17)
+
+
+### Bug Fixes
+
+* **complement-race:** implement client-side momentum with continuous decay for smooth train movement ([ea19ff9](https://github.com/antialias/soroban-abacus-flashcards/commit/ea19ff918bc70ad3eb0339e18dbd32195f34816e))
+
+## [4.4.7](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.4.6...v4.4.7) (2025-10-17)
+
+
+### Bug Fixes
+
+* **complement-race:** add missing useRef import ([d43829a](https://github.com/antialias/soroban-abacus-flashcards/commit/d43829ad48f7ee879a46879f5e6ac1256db1f564))
+
+## [4.4.6](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.4.5...v4.4.6) (2025-10-17)
+
+
+### Bug Fixes
+
+* **complement-race:** restore smooth train movement with client-side game loop ([46a80cb](https://github.com/antialias/soroban-abacus-flashcards/commit/46a80cbcc8ec39224d4edaf540da25611d48fbdd))
+
+## [4.4.5](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.4.4...v4.4.5) (2025-10-17)
+
+
+### Bug Fixes
+
+* **complement-race:** add missing useEffect import ([3054130](https://github.com/antialias/soroban-abacus-flashcards/commit/30541304dd0f0801860dd62967f7f7cae717bcdd))
+
+## [4.4.4](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.4.3...v4.4.4) (2025-10-17)
+
+
+### Bug Fixes
+
+* **complement-race:** add pressure decay system and improve logging ([66992e8](https://github.com/antialias/soroban-abacus-flashcards/commit/66992e877065a42d00379ef8fae0a6e252b0ffcb))
+
+## [4.4.3](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.4.2...v4.4.3) (2025-10-17)
+
+
+### Bug Fixes
+
+* **complement-race:** train now moves in sprint mode ([54b46e7](https://github.com/antialias/soroban-abacus-flashcards/commit/54b46e771e654721e7fabb1f45ecd45daf8e447f))
+
+
+### Code Refactoring
+
+* simplify train debug logs to strings only ([334a49c](https://github.com/antialias/soroban-abacus-flashcards/commit/334a49c92e112c852c483b5dbe3a3d0aef8a5c03))
+
+## [4.4.2](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.4.1...v4.4.2) (2025-10-17)
+
+
+### Code Refactoring
+
+* **complement-race:** remove verbose logging, keep only train debug logs ([86af2fe](https://github.com/antialias/soroban-abacus-flashcards/commit/86af2fe902b3d3790b7b4659fdc698caed8e4dd9))
+
 ## [4.4.1](https://github.com/antialias/soroban-abacus-flashcards/compare/v4.4.0...v4.4.1) (2025-10-17)
 
 

apps/web/src/app/arcade/complement-race/components/GameDisplay.tsx

@@ -5,7 +5,6 @@ import { useComplementRace } from '@/arcade-games/complement-race/Provider'
 import { useAdaptiveDifficulty } from '../hooks/useAdaptiveDifficulty'
 import { useAIRacers } from '../hooks/useAIRacers'
 import { useSoundEffects } from '../hooks/useSoundEffects'
-import { useSteamJourney } from '../hooks/useSteamJourney'
 import { generatePassengers } from '../lib/passengerGenerator'
 import { AbacusTarget } from './AbacusTarget'
 import { CircularTrack } from './RaceTrack/CircularTrack'
@@ -16,10 +15,9 @@ import { RouteCelebration } from './RouteCelebration'
 type FeedbackAnimation = 'correct' | 'incorrect' | null
 
 export function GameDisplay() {
-  const { state, dispatch } = useComplementRace()
+  const { state, dispatch, boostMomentum } = useComplementRace()
   useAIRacers() // Activate AI racer updates (not used in sprint mode)
   const { trackPerformance, getAdaptiveFeedbackMessage } = useAdaptiveDifficulty()
-  const { boostMomentum } = useSteamJourney()
   const { playSound } = useSoundEffects()
   const [feedbackAnimation, setFeedbackAnimation] = useState<FeedbackAnimation>(null)
 
@@ -70,12 +68,6 @@ export function GameDisplay() {
       // Only process number keys
       if (/^[0-9]$/.test(e.key)) {
         const newInput = state.currentInput + e.key
-        console.log('⌨️ [KeyPress] Number key pressed:', {
-          key: e.key,
-          oldInput: state.currentInput,
-          newInput,
-          currentQuestion: state.currentQuestion?.number,
-        })
         dispatch({ type: 'UPDATE_INPUT', input: newInput })
 
         // Check if answer is complete
@@ -83,27 +75,12 @@ export function GameDisplay() {
           const answer = parseInt(newInput, 10)
           const correctAnswer = state.currentQuestion.correctAnswer
 
-          console.log('🔍 [KeyPress] Checking answer:', {
-            newInput,
-            newInputLength: newInput.length,
-            correctAnswer,
-            correctAnswerLength: correctAnswer.toString().length,
-            willSubmit: newInput.length >= correctAnswer.toString().length,
-          })
-
           // If we have enough digits to match the answer, submit
           if (newInput.length >= correctAnswer.toString().length) {
             const responseTime = Date.now() - state.questionStartTime
             const isCorrect = answer === correctAnswer
             const pairKey = `${state.currentQuestion.number}_${state.currentQuestion.correctAnswer}_${state.currentQuestion.targetSum}`
 
-            console.log('📝 [KeyPress] Submitting answer:', {
-              answer,
-              correctAnswer,
-              isCorrect,
-              responseTime,
-            })
-
             if (isCorrect) {
               // Correct answer
               dispatch({ type: 'SUBMIT_ANSWER', answer })
@@ -130,7 +107,7 @@ export function GameDisplay() {
 
               // Boost momentum for sprint mode
               if (state.style === 'sprint') {
-                boostMomentum()
+                boostMomentum(true)
 
                 // Play train whistle for milestones in sprint mode (line 13222-13235)
                 if (newStreak >= 5 && newStreak % 3 === 0) {
@@ -154,7 +131,6 @@ export function GameDisplay() {
                 dispatch({ type: 'SHOW_ADAPTIVE_FEEDBACK', feedback })
               }
 
-              console.log('➡️ [KeyPress] Dispatching NEXT_QUESTION after correct answer')
               dispatch({ type: 'NEXT_QUESTION' })
             } else {
               // Incorrect answer
@@ -166,22 +142,22 @@ export function GameDisplay() {
               // Play incorrect sound (from web_generator.py line 11589)
               playSound('incorrect')
 
+              // Reduce momentum for sprint mode
+              if (state.style === 'sprint') {
+                boostMomentum(false)
+              }
+
               // Show adaptive feedback
               const feedback = getAdaptiveFeedbackMessage(pairKey, false, responseTime)
               if (feedback) {
                 dispatch({ type: 'SHOW_ADAPTIVE_FEEDBACK', feedback })
               }
 
-              console.log('❌ [KeyPress] Incorrect answer - clearing input')
               dispatch({ type: 'UPDATE_INPUT', input: '' })
             }
           }
         }
       } else if (e.key === 'Backspace') {
-        console.log('⌫ [KeyPress] Backspace pressed:', {
-          oldInput: state.currentInput,
-          newInput: state.currentInput.slice(0, -1),
-        })
         dispatch({
           type: 'UPDATE_INPUT',
           input: state.currentInput.slice(0, -1),
@@ -189,16 +165,8 @@ export function GameDisplay() {
       }
     }
 
-    console.log('🔄 [KeyPress Effect] Setting up keyboard listener with state:', {
-      currentInput: state.currentInput,
-      currentQuestion: state.currentQuestion?.number,
-    })
-
     window.addEventListener('keydown', handleKeyPress)
-    return () => {
-      console.log('🧹 [KeyPress Effect] Cleaning up keyboard listener')
-      window.removeEventListener('keydown', handleKeyPress)
-    }
+    return () => window.removeEventListener('keydown', handleKeyPress)
   }, [
     state.currentInput,
     state.currentQuestion,
@@ -231,19 +199,6 @@ export function GameDisplay() {
 
   if (!state.currentQuestion) return null
 
-  // DEBUG: Log state on every render
-  console.log('🎮 [GameDisplay] Render:', {
-    currentInput: state.currentInput,
-    currentInputLength: state.currentInput?.length,
-    currentInputType: typeof state.currentInput,
-    currentQuestion: state.currentQuestion,
-    questionNumber: state.currentQuestion?.number,
-    correctAnswer: state.currentQuestion?.correctAnswer,
-    targetSum: state.currentQuestion?.targetSum,
-    score: state.score,
-    streak: state.streak,
-  })
-
   return (
     <div
       data-component="game-display"

apps/web/src/app/arcade/complement-race/components/RaceTrack/SteamTrainJourney.tsx

@@ -94,6 +94,10 @@ export function SteamTrainJourney({
   currentInput,
 }: SteamTrainJourneyProps) {
   const { state } = useComplementRace()
+  console.log(
+    `🚂 Train: mom=${momentum} pos=${trainPosition} stations=${state.stations.length} passengers=${state.passengers.length}`
+  )
+
   const { getSkyGradient, getTimeOfDayPeriod } = useSteamJourney()
   const _skyGradient = getSkyGradient()
   const period = getTimeOfDayPeriod()

apps/web/src/app/arcade/complement-race/context/ComplementRaceContext.tsx

@@ -113,13 +113,6 @@ const initialState: GameState = {
 }
 
 function gameReducer(state: GameState, action: GameAction): GameState {
-  console.log('🔄 [Reducer] Action dispatched:', {
-    type: action.type,
-    action,
-    currentInput: state.currentInput,
-    currentQuestion: state.currentQuestion?.number,
-  })
-
   switch (action.type) {
     case 'SET_MODE':
       return { ...state, mode: action.mode }
@@ -178,8 +171,6 @@ function gameReducer(state: GameState, action: GameAction): GameState {
     }
 
     case 'NEXT_QUESTION': {
-      console.log('➡️ [Reducer] NEXT_QUESTION - clearing input and generating new question')
-
       // Generate new question based on mode
       const generateQuestion = () => {
         let targetSum: number
@@ -221,28 +212,16 @@ function gameReducer(state: GameState, action: GameAction): GameState {
         }
       }
 
-      const newQuestion = generateQuestion()
-      console.log('📊 [Reducer] NEXT_QUESTION result:', {
-        oldQuestion: state.currentQuestion,
-        newQuestion,
-        oldInput: state.currentInput,
-        newInput: '',
-      })
-
       return {
         ...state,
         previousQuestion: state.currentQuestion,
-        currentQuestion: newQuestion,
+        currentQuestion: generateQuestion(),
         questionStartTime: Date.now(),
         currentInput: '',
       }
     }
 
     case 'UPDATE_INPUT':
-      console.log('✏️ [Reducer] UPDATE_INPUT:', {
-        oldInput: state.currentInput,
-        newInput: action.input,
-      })
       return { ...state, currentInput: action.input }
 
     case 'SUBMIT_ANSWER': {

apps/web/src/arcade-games/complement-race/Provider.tsx

@@ -5,7 +5,16 @@
 
 'use client'
 
-import { createContext, useCallback, useContext, useMemo, useState, type ReactNode } from 'react'
+import {
+  createContext,
+  useCallback,
+  useContext,
+  useEffect,
+  useMemo,
+  useRef,
+  useState,
+  type ReactNode,
+} from 'react'
 import {
   type GameMove,
   buildPlayerMetadata,
@@ -102,6 +111,7 @@ interface ComplementRaceContextValue {
   setConfig: (field: keyof ComplementRaceConfig, value: unknown) => void
   clearError: () => void
   exitSession: () => void
+  boostMomentum: (correct: boolean) => void // Client-side momentum boost/reduce
 }
 
 const ComplementRaceContext = createContext<ComplementRaceContextValue | null>(null)
@@ -240,6 +250,32 @@ export function ComplementRaceProvider({ children }: { children: ReactNode }) {
     })
   }, [activePlayers, players])
 
+  // Debug logging ref (track last logged values)
+  const lastLogRef = useState({ key: '', count: 0 })[0]
+
+  // Client-side game state (NOT synced to server - purely visual/gameplay)
+  const [clientMomentum, setClientMomentum] = useState(10) // Start at 10 for gentle push
+  const [clientPosition, setClientPosition] = useState(0)
+  const [clientPressure, setClientPressure] = useState(0)
+  const lastUpdateRef = useRef(Date.now())
+  const gameStartTimeRef = useRef(0)
+
+  // Decay rates based on skill level (momentum lost per second)
+  const MOMENTUM_DECAY_RATES = {
+    preschool: 2.0,
+    kindergarten: 3.5,
+    relaxed: 5.0,
+    slow: 7.0,
+    normal: 9.0,
+    fast: 11.0,
+    expert: 13.0,
+  }
+
+  const MOMENTUM_GAIN_PER_CORRECT = 15
+  const MOMENTUM_LOSS_PER_WRONG = 10
+  const SPEED_MULTIPLIER = 0.15 // momentum * 0.15 = % per second
+  const UPDATE_INTERVAL = 50 // 50ms = ~20fps
+
   // Transform multiplayer state to look like single-player state
   const compatibleState = useMemo((): CompatibleGameState => {
     const localPlayer = localPlayerId ? multiplayerState.players[localPlayerId] : null
@@ -303,10 +339,10 @@ export function ComplementRaceProvider({ children }: { children: ReactNode }) {
         previousPosition: ai.position,
       })),
 
-      // Sprint mode specific
-      momentum: localPlayer?.momentum || 0,
-      trainPosition: localPlayer?.position || 0,
-      pressure: localPlayer?.momentum ? Math.min(100, localPlayer.momentum + 10) : 0,
+      // Sprint mode specific (all client-side for smooth movement)
+      momentum: clientMomentum, // Client-only state with continuous decay
+      trainPosition: clientPosition, // Client-calculated from momentum
+      pressure: clientPressure, // Client-calculated from momentum (0-150 PSI)
       elapsedTime: multiplayerState.gameStartTime ? Date.now() - multiplayerState.gameStartTime : 0,
       lastCorrectAnswerTime: localPlayer?.lastAnswerTime || Date.now(),
       currentRoute: multiplayerState.currentRoute,
@@ -328,7 +364,103 @@ export function ComplementRaceProvider({ children }: { children: ReactNode }) {
       adaptiveFeedback: localUIState.adaptiveFeedback,
       difficultyTracker: localUIState.difficultyTracker,
     }
-  }, [multiplayerState, localPlayerId, localUIState])
+  }, [multiplayerState, localPlayerId, localUIState, clientPosition, clientPressure])
+
+  // Initialize game start time when game becomes active
+  useEffect(() => {
+    if (compatibleState.isGameActive && compatibleState.style === 'sprint') {
+      if (gameStartTimeRef.current === 0) {
+        gameStartTimeRef.current = Date.now()
+        lastUpdateRef.current = Date.now()
+        // Reset client state for new game
+        setClientMomentum(10) // Start with gentle push
+        setClientPosition(0)
+        setClientPressure((10 / 100) * 150) // Initial pressure from starting momentum
+      }
+    } else {
+      // Reset when game ends
+      gameStartTimeRef.current = 0
+    }
+  }, [compatibleState.isGameActive, compatibleState.style])
+
+  // Main client-side game loop: momentum decay and position calculation
+  useEffect(() => {
+    if (!compatibleState.isGameActive || compatibleState.style !== 'sprint') return
+
+    const interval = setInterval(() => {
+      const now = Date.now()
+      const deltaTime = now - lastUpdateRef.current
+      lastUpdateRef.current = now
+
+      // Get decay rate based on skill level
+      const decayRate =
+        MOMENTUM_DECAY_RATES[compatibleState.timeoutSetting as keyof typeof MOMENTUM_DECAY_RATES] ||
+        MOMENTUM_DECAY_RATES.normal
+
+      setClientMomentum((prevMomentum) => {
+        // Calculate momentum decay for this frame
+        const momentumLoss = (decayRate * deltaTime) / 1000
+
+        // Update momentum (don't go below 0)
+        const newMomentum = Math.max(0, prevMomentum - momentumLoss)
+
+        // Calculate speed from momentum (% per second)
+        const speed = newMomentum * SPEED_MULTIPLIER
+
+        // Update position (accumulate, never go backward)
+        const positionDelta = (speed * deltaTime) / 1000
+        setClientPosition((prev) => prev + positionDelta)
+
+        // Calculate pressure (0-150 PSI)
+        const pressure = Math.min(150, (newMomentum / 100) * 150)
+        setClientPressure(pressure)
+
+        return newMomentum
+      })
+    }, UPDATE_INTERVAL)
+
+    return () => clearInterval(interval)
+  }, [
+    compatibleState.isGameActive,
+    compatibleState.style,
+    compatibleState.timeoutSetting,
+    MOMENTUM_DECAY_RATES,
+    SPEED_MULTIPLIER,
+    UPDATE_INTERVAL,
+  ])
+
+  // Reset client position when route changes
+  useEffect(() => {
+    const currentRoute = multiplayerState.currentRoute
+    // When route changes, reset position and give starting momentum
+    if (currentRoute > 1 && compatibleState.style === 'sprint') {
+      setClientPosition(0)
+      setClientMomentum(10) // Reset to starting momentum (gentle push)
+    }
+  }, [multiplayerState.currentRoute, compatibleState.style])
+
+  // Debug logging: only log on answer submission or significant events
+  useEffect(() => {
+    if (compatibleState.style === 'sprint' && compatibleState.isGameActive) {
+      const key = `${compatibleState.correctAnswers}`
+
+      // Only log on new answers (not every frame)
+      if (lastLogRef.key !== key) {
+        console.log(
+          `🚂 Answer #${compatibleState.correctAnswers}: momentum=${compatibleState.momentum} pos=${Math.floor(compatibleState.trainPosition)} pressure=${compatibleState.pressure} streak=${compatibleState.streak}`
+        )
+        lastLogRef.key = key
+      }
+    }
+  }, [
+    compatibleState.correctAnswers,
+    compatibleState.momentum,
+    compatibleState.trainPosition,
+    compatibleState.pressure,
+    compatibleState.streak,
+    compatibleState.style,
+    compatibleState.isGameActive,
+  ])
 
   // Action creators
   const startGame = useCallback(() => {
@@ -482,8 +614,6 @@ export function ComplementRaceProvider({ children }: { children: ReactNode }) {
   // Compatibility dispatch function for existing UI components
   const dispatch = useCallback(
     (action: { type: string; [key: string]: any }) => {
-      console.log('[ComplementRaceProvider] dispatch called (compatibility layer):', action.type)
-
       // Map old reducer actions to new action creators
       switch (action.type) {
         case 'START_COUNTDOWN':
@@ -497,7 +627,6 @@ export function ComplementRaceProvider({ children }: { children: ReactNode }) {
           }
           break
         case 'NEXT_QUESTION':
-          console.log('🧹 [Provider] NEXT_QUESTION - clearing local input state')
           setLocalUIState((prev) => ({ ...prev, currentInput: '' }))
           nextQuestion()
           break
@@ -603,6 +732,22 @@ export function ComplementRaceProvider({ children }: { children: ReactNode }) {
     ]
   )
 
+  // Client-side momentum boost/reduce (sprint mode only)
+  const boostMomentum = useCallback(
+    (correct: boolean) => {
+      if (compatibleState.style !== 'sprint') return
+
+      setClientMomentum((prevMomentum) => {
+        if (correct) {
+          return Math.min(100, prevMomentum + MOMENTUM_GAIN_PER_CORRECT)
+        } else {
+          return Math.max(0, prevMomentum - MOMENTUM_LOSS_PER_WRONG)
+        }
+      })
+    },
+    [compatibleState.style, MOMENTUM_GAIN_PER_CORRECT, MOMENTUM_LOSS_PER_WRONG]
+  )
+
   const contextValue: ComplementRaceContextValue = {
     state: compatibleState, // Use transformed state
     dispatch,
@@ -618,6 +763,7 @@ export function ComplementRaceProvider({ children }: { children: ReactNode }) {
     setConfig,
     clearError,
     exitSession,
+    boostMomentum, // Client-side momentum control
   }
 
   return (

apps/web/src/arcade-games/complement-race/Validator.ts

@@ -168,8 +168,7 @@ export class ComplementRaceValidator
         bestStreak: 0,
         correctAnswers: 0,
         totalQuestions: 0,
-        position: 0,
-        momentum: 50, // Start with some momentum in sprint mode
+        position: 0, // Only used for practice/survival; sprint mode is client-side
         isReady: false,
         isActive: true,
         currentAnswer: null,
@@ -317,12 +316,9 @@ export class ComplementRaceValidator
         updatedPlayer.position = Math.min(100, player.position + 100 / state.config.raceGoal)
       }
     } else if (state.config.style === 'sprint') {
-      // Sprint: Update momentum
-      if (correct) {
-        updatedPlayer.momentum = Math.min(100, player.momentum + 15)
-      } else {
-        updatedPlayer.momentum = Math.max(0, player.momentum - 10)
-      }
+      // Sprint: All momentum/position handled client-side for smooth 20fps movement
+      // Server only tracks scoring, passengers, and game progression
+      // No server-side position updates needed
     } else if (state.config.style === 'survival') {
       // Survival: Always move forward, speed based on accuracy
       const moveDistance = correct ? 5 : 2
@@ -522,12 +518,12 @@ export class ComplementRaceValidator
       return { valid: false, error: 'Routes only available in sprint mode' }
     }
 
-    // Reset all player positions to 0
+    // Reset all player positions to 0 for new route (client handles momentum reset)
     const resetPlayers: Record<string, PlayerState> = {}
     for (const [playerId, player] of Object.entries(state.players)) {
       resetPlayers[playerId] = {
         ...player,
-        position: 0,
+        position: 0, // Server position not used in sprint; client will reset
         passengers: [], // Clear any remaining passengers
       }
     }

apps/web/src/arcade-games/complement-race/types.ts

@@ -61,8 +61,7 @@ export interface PlayerState {
   totalQuestions: number
 
   // Position & Progress
-  position: number // 0-100% for practice/sprint, lap count for survival
-  momentum: number // 0-100 (sprint mode only)
+  position: number // 0-100% for practice/survival only (sprint mode: client-side)
 
   // Current state
   isReady: boolean

package.json

@@ -1,6 +1,6 @@
 {
   "name": "soroban-monorepo",
-  "version": "4.4.1",
+  "version": "4.4.9",
   "private": true,
   "description": "Beautiful Soroban Flashcard Generator - Monorepo",
   "workspaces": [