# Know Foolery - Development Guidelines & Coding Standards

## Overview

This document establishes coding standards, development practices, and guidelines for the Know Foolery project to ensure consistency, maintainability, and quality across the codebase.

## Code Quality Standards

### General Code Quality Orientations
- **Type Safety**: TypeScript for frontend, Go's type system for backend
- **Code Review**: Mandatory peer review for all changes
- **Static Analysis**: Automated code quality checks
- **Documentation**: Comprehensive API and component documentation

### Linting and Formatting
```yaml
# .golangci.yml
run:
  timeout: 5m
  tests: true

linters:
  enable:
    - gofmt
    - goimports
    - govet
    - errcheck
    - staticcheck
    - unused
    - gosimple
    - structcheck
    - varcheck
    - ineffassign
    - deadcode
    - typecheck
    - gosec
    - misspell
    - lll
    - unconvert
    - dupl
    - goconst
    - gocyclo

linters-settings:
  lll:
    line-length: 120
  gocyclo:
    min-complexity: 15
  dupl:
    threshold: 150

issues:
  exclude-rules:
    - path: _test\.go
      linters:
        - gocyclo
        - errcheck
        - dupl
        - gosec
```

```json
// .eslintrc.json
{
  "extends": [
    "plugin:solid/typescript",
    "@typescript-eslint/recommended",
    "prettier"
  ],
  "parser": "@typescript-eslint/parser",
  "plugins": ["@typescript-eslint", "solid"],
  "rules": {
    "@typescript-eslint/explicit-function-return-type": "error",
    "@typescript-eslint/no-unused-vars": "error",
    "@typescript-eslint/prefer-const": "error",
    "solid/reactivity": "warn",
    "prefer-const": "error",
    "no-var": "error",
    "object-shorthand": "error",
    "prefer-template": "error"
  }
}
```

### Naming Conventions

#### Go Code
```go
// Files: snake_case
user_service.go
jwt_middleware.go
database_client.go

// Packages: lowercase, single word when possible
package auth
package database
package observability

// Exported types: PascalCase
type GameService struct {}
type AuthClaims struct {}
type DatabaseConfig struct {}

// Unexported types: camelCase
type userRepository struct {}
type tokenValidator struct {}

// Functions: PascalCase (exported), camelCase (unexported)
func NewGameService() *GameService {}
func (s *GameService) StartGame() error {}
func validateToken() error {}

// Constants: PascalCase or SCREAMING_SNAKE_CASE for groups
const DefaultTimeout = 30 * time.Second
const (
    StatusActive   = "active"
    StatusInactive = "inactive"
)

// Interfaces: noun or adjective + "er" suffix
type TokenValidator interface {}
type UserRepository interface {}
type ScoreCalculator interface {}
```

#### TypeScript Code
```typescript
// Files: kebab-case
game-card.tsx
user-service.ts
auth-store.ts

// Components: PascalCase
export const GameCard: Component<GameCardProps> = () => {}
export const LeaderboardList: Component = () => {}

// Composables/stores: camelCase with "create"/"use" prefix
export const createGameSessionStore = () => {}
export const useAuthentication = () => {}

// Functions: camelCase
export const calculateScore = () => {}
export const validateAnswer = () => {}

// Types/Interfaces: PascalCase
interface GameSessionProps {}
type AuthenticationState = 'loading' | 'authenticated' | 'unauthenticated'

// Constants: SCREAMING_SNAKE_CASE
export const MAX_ATTEMPTS = 3
export const SESSION_TIMEOUT = 30 * 60 * 1000 // 30 minutes
```

## Go Development Standards

### Fiber Framework Patterns

#### Service Structure
```go
// Service initialization with Fiber
package main

import (
    "log"
    "github.com/gofiber/fiber/v3"
    "github.com/gofiber/fiber/v3/middleware/cors"
    "github.com/gofiber/fiber/v3/middleware/logger"
    "github.com/gofiber/fiber/v3/middleware/recover"
)

func main() {
    // Create Fiber app with configuration
    app := fiber.New(fiber.Config{
        AppName:      "Know Foolery Game Service",
        ServerHeader: "Fiber",
        ErrorHandler: customErrorHandler,
        ReadTimeout:  time.Second * 10,
        WriteTimeout: time.Second * 10,
        IdleTimeout:  time.Second * 120,
    })

    // Global middleware
    app.Use(logger.New())
    app.Use(recover.New())
    app.Use(cors.New(cors.Config{
        AllowOrigins: "http://localhost:3000, https://app.knowfoolery.com",
        AllowMethods: "GET,POST,PUT,DELETE,OPTIONS",
        AllowHeaders: "Origin, Content-Type, Authorization",
    }))

    // Health check endpoint
    app.Get("/health", healthCheck)

    // API routes with versioning
    api := app.Group("/api/v1")
    setupGameRoutes(api)

    // Start server
    log.Fatal(app.Listen(":8080"))
}

func customErrorHandler(c *fiber.Ctx, err error) error {
    code := fiber.StatusInternalServerError
    message := "Internal Server Error"

    if e, ok := err.(*fiber.Error); ok {
        code = e.Code
        message = e.Message
    }

    return c.Status(code).JSON(fiber.Map{
        "error":   true,
        "message": message,
        "code":    code,
    })
}
```

#### Handler Patterns
```go
// Handler structure and patterns
package handlers

import (
    "github.com/gofiber/fiber/v3"
    "knowfoolery/internal/services"
)

type GameHandler struct {
    gameService *services.GameService
    validator   *validator.Validate
}

func NewGameHandler(gameService *services.GameService) *GameHandler {
    return &GameHandler{
        gameService: gameService,
        validator:   validator.New(),
    }
}

// HTTP handler with proper error handling
func (h *GameHandler) StartGame(c *fiber.Ctx) error {
    var req StartGameRequest
    
    // Parse and validate request
    if err := c.BodyParser(&req); err != nil {
        return c.Status(fiber.StatusBadRequest).JSON(fiber.Map{
            "error":   true,
            "message": "Invalid request body",
        })
    }
    
    if err := h.validator.Struct(&req); err != nil {
        return c.Status(fiber.StatusBadRequest).JSON(fiber.Map{
            "error":   true,
            "message": "Validation failed",
            "details": err.Error(),
        })
    }
    
    // Extract user context from JWT middleware
    userID := c.Locals("user_id").(string)
    userRole := c.Locals("user_role").(string)
    
    // Business logic
    gameSession, err := h.gameService.StartGame(c.Context(), userID, req.PlayerName)
    if err != nil {
        return handleServiceError(c, err)
    }
    
    return c.Status(fiber.StatusCreated).JSON(fiber.Map{
        "success": true,
        "data":    gameSession,
    })
}

// Centralized error handling
func handleServiceError(c *fiber.Ctx, err error) error {
    switch {
    case errors.Is(err, services.ErrInvalidInput):
        return c.Status(fiber.StatusBadRequest).JSON(fiber.Map{
            "error":   true,
            "message": "Invalid input",
            "details": err.Error(),
        })
    case errors.Is(err, services.ErrNotFound):
        return c.Status(fiber.StatusNotFound).JSON(fiber.Map{
            "error":   true,
            "message": "Resource not found",
        })
    case errors.Is(err, services.ErrUnauthorized):
        return c.Status(fiber.StatusUnauthorized).JSON(fiber.Map{
            "error":   true,
            "message": "Unauthorized access",
        })
    default:
        return c.Status(fiber.StatusInternalServerError).JSON(fiber.Map{
            "error":   true,
            "message": "Internal server error",
        })
    }
}

// Request/Response structures with validation
type StartGameRequest struct {
    PlayerName string `json:"player_name" validate:"required,min=2,max=50,alphanum_space"`
}

type StartGameResponse struct {
    SessionID     string    `json:"session_id"`
    PlayerName    string    `json:"player_name"`
    StartTime     time.Time `json:"start_time"`
    TimeRemaining int       `json:"time_remaining_seconds"`
}
```

#### Middleware Patterns
```go
// Custom middleware for authentication
package middleware

import (
    "github.com/gofiber/fiber/v3"
    "knowfoolery/shared/auth"
)

func JWTMiddleware(zitadelRepo auth.ZitadelRepository) fiber.Handler {
    return func(c *fiber.Ctx) error {
        // Extract token from Authorization header
        authHeader := c.Get("Authorization")
        if authHeader == "" {
            return c.Status(fiber.StatusUnauthorized).JSON(fiber.Map{
                "error":   true,
                "message": "Authorization header required",
            })
        }
        
        token := strings.TrimPrefix(authHeader, "Bearer ")
        if token == authHeader {
            return c.Status(fiber.StatusUnauthorized).JSON(fiber.Map{
                "error":   true,
                "message": "Invalid authorization header format",
            })
        }
        
        // Validate token
        claims, err := zitadelRepo.ValidateToken(c.Context(), token)
        if err != nil {
            return c.Status(fiber.StatusUnauthorized).JSON(fiber.Map{
                "error":   true,
                "message": "Invalid token",
            })
        }
        
        // Set user context
        c.Locals("user_id", claims.Subject)
        c.Locals("user_email", claims.Email)
        c.Locals("user_name", claims.Name)
        c.Locals("user_roles", claims.Roles)
        
        return c.Next()
    }
}

// Rate limiting middleware
func RateLimitMiddleware(redisClient *redis.Client) fiber.Handler {
    return func(c *fiber.Ctx) error {
        userID := c.Locals("user_id")
        clientIP := c.IP()
        
        // Per-user rate limiting
        if userID != nil {
            userKey := fmt.Sprintf("rate_limit:user:%s", userID)
            if !allowRequest(redisClient, userKey, 60, time.Minute) {
                return c.Status(fiber.StatusTooManyRequests).JSON(fiber.Map{
                    "error":   true,
                    "message": "Rate limit exceeded for user",
                })
            }
        }
        
        // Per-IP rate limiting
        ipKey := fmt.Sprintf("rate_limit:ip:%s", clientIP)
        if !allowRequest(redisClient, ipKey, 100, time.Minute) {
            return c.Status(fiber.StatusTooManyRequests).JSON(fiber.Map{
                "error":   true,
                "message": "Rate limit exceeded for IP",
            })
        }
        
        return c.Next()
    }
}
```

### Database Patterns with Ent

#### Schema Definition Standards
```go
// Ent schema with proper field validation and indexes
package schema

import (
    "entgo.io/ent"
    "entgo.io/ent/schema/edge"
    "entgo.io/ent/schema/field"
    "entgo.io/ent/schema/index"
    "time"
)

type Question struct {
    ent.Schema
}

func (Question) Fields() []ent.Field {
    return []ent.Field{
        field.String("theme").
            NotEmpty().
            MaxLen(100).
            Comment("Question category/theme"),
        field.Text("text").
            NotEmpty().
            MaxLen(1000).
            Comment("The actual question text"),
        field.String("answer").
            NotEmpty().
            MaxLen(500).
            Comment("Correct answer"),
        field.Text("hint").
            Optional().
            MaxLen(500).
            Comment("Optional hint text"),
        field.Enum("difficulty").
            Values("easy", "medium", "hard").
            Default("medium").
            Comment("Question difficulty level"),
        field.Bool("is_active").
            Default(true).
            Comment("Whether question is active"),
        field.Time("created_at").
            Default(time.Now).
            Immutable().
            Comment("Creation timestamp"),
        field.Time("updated_at").
            Default(time.Now).
            UpdateDefault(time.Now).
            Comment("Last update timestamp"),
    }
}

func (Question) Indexes() []ent.Index {
    return []ent.Index{
        index.Fields("theme", "is_active"),
        index.Fields("difficulty", "is_active"),
        index.Fields("created_at"),
    }
}

func (Question) Edges() []ent.Edge {
    return []ent.Edge{
        edge.To("attempts", QuestionAttempt.Type),
    }
}
```

#### Service Layer Patterns
```go
// Service layer with proper error handling
package services

import (
    "context"
    "errors"
    "knowfoolery/internal/models"
    "knowfoolery/ent"
)

var (
    ErrInvalidInput    = errors.New("invalid input")
    ErrNotFound        = errors.New("resource not found")
    ErrUnauthorized    = errors.New("unauthorized access")
    ErrGameInProgress  = errors.New("game already in progress")
    ErrSessionExpired  = errors.New("session expired")
)

type GameService struct {
    client       *ent.Client
    questionSvc  QuestionService
    sessionSvc   SessionService
    validator    *validator.Validate
}

func NewGameService(
    client *ent.Client,
    questionSvc QuestionService,
    sessionSvc SessionService,
) *GameService {
    return &GameService{
        client:      client,
        questionSvc: questionSvc,
        sessionSvc:  sessionSvc,
        validator:   validator.New(),
    }
}

func (s *GameService) StartGame(ctx context.Context, userID, playerName string) (*models.GameSession, error) {
    // Validate input
    if err := s.validatePlayerName(playerName); err != nil {
        return nil, fmt.Errorf("%w: %v", ErrInvalidInput, err)
    }
    
    // Check for existing active session
    activeSession, err := s.client.GameSession.
        Query().
        Where(gamesession.And(
            gamesession.PlayerNameEQ(playerName),
            gamesession.StatusEQ(gamesession.StatusActive),
        )).
        Only(ctx)
    
    if err != nil && !ent.IsNotFound(err) {
        return nil, fmt.Errorf("failed to check existing session: %w", err)
    }
    
    if activeSession != nil {
        return nil, ErrGameInProgress
    }
    
    // Start database transaction
    tx, err := s.client.Tx(ctx)
    if err != nil {
        return nil, fmt.Errorf("failed to start transaction: %w", err)
    }
    defer tx.Rollback()
    
    // Create new game session
    session, err := tx.GameSession.
        Create().
        SetPlayerName(playerName).
        SetTotalScore(0).
        SetQuestionsAsked(0).
        SetQuestionsCorrect(0).
        SetHintsUsed(0).
        SetStartTime(time.Now()).
        SetStatus(gamesession.StatusActive).
        Save(ctx)
    if err != nil {
        return nil, fmt.Errorf("failed to create session: %w", err)
    }
    
    // Get first question
    question, err := s.questionSvc.GetRandomQuestion(ctx)
    if err != nil {
        return nil, fmt.Errorf("failed to get question: %w", err)
    }
    
    // Update session with first question
    session, err = session.Update().
        SetCurrentQuestionID(question.ID).
        SetCurrentAttempts(0).
        Save(ctx)
    if err != nil {
        return nil, fmt.Errorf("failed to update session: %w", err)
    }
    
    // Commit transaction
    if err := tx.Commit(); err != nil {
        return nil, fmt.Errorf("failed to commit transaction: %w", err)
    }
    
    return &models.GameSession{
        ID:            session.ID,
        PlayerName:    session.PlayerName,
        TotalScore:    session.TotalScore,
        StartTime:     session.StartTime,
        Status:        string(session.Status),
        CurrentQuestion: &models.Question{
            ID:     question.ID,
            Theme:  question.Theme,
            Text:   question.Text,
            Hint:   question.Hint,
        },
        TimeRemaining: s.calculateTimeRemaining(session.StartTime),
    }, nil
}

func (s *GameService) validatePlayerName(name string) error {
    type PlayerNameValidation struct {
        Name string `validate:"required,min=2,max=50,alphanum_space"`
    }
    
    return s.validator.Struct(&PlayerNameValidation{Name: name})
}

func (s *GameService) calculateTimeRemaining(startTime time.Time) int {
    const sessionDuration = 30 * time.Minute
    elapsed := time.Since(startTime)
    remaining := sessionDuration - elapsed
    
    if remaining < 0 {
        return 0
    }
    
    return int(remaining.Seconds())
}
```

## TypeScript Development Standards

### SolidJS Component Patterns

#### Component Structure
```typescript
// Component with proper TypeScript types and SolidJS patterns
import type { Component } from 'solid-js'
import { createMemo, createSignal, Show } from 'solid-js'
import {
  Box,
  Button,
  Input,
  LinearProgress,
  Typography,
  Chip,
} from '@suid/material'

// Props interface with proper documentation
export interface GameCardProps {
  /** The question to display */
  question: string
  /** Theme/category of the question */
  theme: string
  /** Time remaining in seconds */
  timeRemaining: number
  /** Number of attempts left */
  attemptsLeft: number
  /** Callback when answer is submitted */
  onSubmitAnswer: (answer: string) => Promise<void>
  /** Loading state from async operations */
  loading?: boolean
}

/**
 * GameCard component displays a quiz question with input and controls
 *
 * @param props - GameCard props
 * @returns SolidJS component
 */
export const GameCard: Component<GameCardProps> = (props) => {
  const [answer, setAnswer] = createSignal('')
  const [isSubmitting, setIsSubmitting] = createSignal(false)

  const disabled = createMemo(() => props.loading || isSubmitting())
  const progressValue = createMemo(() => ((30 * 60 - props.timeRemaining) / (30 * 60)) * 100)

  const handleSubmit = async () => {
    const value = answer().trim()
    if (!value || disabled()) return

    setIsSubmitting(true)
    try {
      await props.onSubmitAnswer(value)
      setAnswer('')
    } catch (error) {
      console.error('Failed to submit answer:', error)
    } finally {
      setIsSubmitting(false)
    }
  }

  return (
    <Box sx={{ p: 3, border: '1px solid', borderColor: 'divider', borderRadius: 2 }}>
      <Box sx={{ display: 'flex', justifyContent: 'space-between', mb: 1 }}>
        <Chip label={props.theme} />
        <Typography variant="body2">{props.timeRemaining}s</Typography>
      </Box>
      <LinearProgress variant="determinate" value={progressValue()} />
      <Typography variant="h6" sx={{ mt: 2 }}>{props.question}</Typography>
      <Typography variant="body2" sx={{ mt: 1 }}>Attempts left: {props.attemptsLeft}/3</Typography>
      <Input
        value={answer()}
        onInput={(e) => setAnswer(e.currentTarget.value)}
        disabled={disabled()}
        placeholder="Enter your answer"
      />
      <Button onClick={handleSubmit} disabled={disabled() || answer().trim().length === 0}>
        Submit Answer
      </Button>
      <Show when={disabled()}>
        <Typography variant="caption">Submitting...</Typography>
      </Show>
    </Box>
  )
}
```

#### Solid Composable Pattern
```typescript
import { createSignal } from 'solid-js'
import { GameSessionService } from '../services/game-session-service'

export const createGameSessionStore = (playerName: () => string) => {
  const service = new GameSessionService()
  const [isLoading, setIsLoading] = createSignal(false)
  const [error, setError] = createSignal<string | null>(null)
  const [sessionId, setSessionId] = createSignal<string | null>(null)

  const startGame = async () => {
    setIsLoading(true)
    setError(null)
    try {
      const session = await service.startGame(playerName())
      setSessionId(session.sessionId)
      return session
    } catch (err) {
      const message = err instanceof Error ? err.message : 'Failed to start game'
      setError(message)
      throw err
    } finally {
      setIsLoading(false)
    }
  }

  return {
    isLoading,
    error,
    sessionId,
    startGame,
  }
}
```

## Testing Standards

### Go Testing Patterns
```go
// Comprehensive testing with testify and testcontainers
package services_test

import (
    "context"
    "testing"
    "time"
    
    "github.com/stretchr/testify/assert"
    "github.com/stretchr/testify/require"
    "github.com/stretchr/testify/suite"
    "github.com/testcontainers/testcontainers-go/modules/postgres"
    
    "knowfoolery/internal/services"
    "knowfoolery/ent/enttest"
)

type GameServiceTestSuite struct {
    suite.Suite
    ctx         context.Context
    gameService *services.GameService
    client      *ent.Client
}

func (suite *GameServiceTestSuite) SetupSuite() {
    suite.ctx = context.Background()
    
    // Start PostgreSQL container for integration tests
    postgresContainer, err := postgres.RunContainer(suite.ctx,
        testcontainers.WithImage("postgres:15-alpine"),
        postgres.WithDatabase("testdb"),
        postgres.WithUsername("testuser"),
        postgres.WithPassword("testpass"),
    )
    require.NoError(suite.T(), err)
    
    connStr, err := postgresContainer.ConnectionString(suite.ctx)
    require.NoError(suite.T(), err)
    
    // Create Ent client with test database
    suite.client = enttest.Open(suite.T(), "postgres", connStr)
    
    // Initialize service
    suite.gameService = services.NewGameService(
        suite.client,
        services.NewQuestionService(suite.client),
        services.NewSessionService(suite.client),
    )
}

func (suite *GameServiceTestSuite) TearDownSuite() {
    suite.client.Close()
}

func (suite *GameServiceTestSuite) SetupTest() {
    // Clean database before each test
    suite.client.GameSession.Delete().ExecX(suite.ctx)
    suite.client.Question.Delete().ExecX(suite.ctx)
    
    // Seed test data
    suite.seedTestQuestions()
}

func (suite *GameServiceTestSuite) TestStartGame_Success() {
    // Arrange
    playerName := "TestPlayer"
    
    // Act
    session, err := suite.gameService.StartGame(suite.ctx, "user123", playerName)
    
    // Assert
    require.NoError(suite.T(), err)
    assert.NotEmpty(suite.T(), session.ID)
    assert.Equal(suite.T(), playerName, session.PlayerName)
    assert.Equal(suite.T(), 0, session.TotalScore)
    assert.NotNil(suite.T(), session.CurrentQuestion)
    assert.True(suite.T(), session.TimeRemaining > 0)
}

func (suite *GameServiceTestSuite) TestStartGame_InvalidPlayerName() {
    // Test cases for validation
    testCases := []struct {
        name        string
        playerName  string
        expectedErr string
    }{
        {"empty name", "", "required"},
        {"too short", "a", "min"},
        {"too long", strings.Repeat("a", 51), "max"},
        {"invalid chars", "player@123", "alphanum_space"},
    }
    
    for _, tc := range testCases {
        suite.T().Run(tc.name, func(t *testing.T) {
            _, err := suite.gameService.StartGame(suite.ctx, "user123", tc.playerName)
            require.Error(t, err)
            assert.Contains(t, err.Error(), tc.expectedErr)
        })
    }
}

func (suite *GameServiceTestSuite) TestStartGame_ExistingActiveSession() {
    // Arrange
    playerName := "TestPlayer"
    
    // Start first game
    _, err := suite.gameService.StartGame(suite.ctx, "user123", playerName)
    require.NoError(suite.T(), err)
    
    // Act - try to start second game
    _, err = suite.gameService.StartGame(suite.ctx, "user123", playerName)
    
    // Assert
    require.Error(suite.T(), err)
    assert.Equal(suite.T(), services.ErrGameInProgress, err)
}

func (suite *GameServiceTestSuite) seedTestQuestions() {
    questions := []struct {
        theme  string
        text   string
        answer string
        hint   string
    }{
        {"Geography", "What is the capital of France?", "Paris", "City of Light"},
        {"History", "Who painted the Mona Lisa?", "Leonardo da Vinci", "Renaissance artist"},
        {"Science", "What is the largest planet?", "Jupiter", "Gas giant"},
    }
    
    for _, q := range questions {
        suite.client.Question.Create().
            SetTheme(q.theme).
            SetText(q.text).
            SetAnswer(q.answer).
            SetHint(q.hint).
            SetIsActive(true).
            ExecX(suite.ctx)
    }
}

func TestGameServiceSuite(t *testing.T) {
    suite.Run(t, new(GameServiceTestSuite))
}

// Benchmark tests
func BenchmarkGameService_StartGame(b *testing.B) {
    // Setup
    ctx := context.Background()
    client := enttest.Open(b, "sqlite3", "file:ent?mode=memory&cache=shared&_fk=1")
    defer client.Close()
    
    gameService := services.NewGameService(client, nil, nil)
    
    // Benchmark
    b.ResetTimer()
    for i := 0; i < b.N; i++ {
        playerName := fmt.Sprintf("Player%d", i)
        _, _ = gameService.StartGame(ctx, fmt.Sprintf("user%d", i), playerName)
    }
}
```

### TypeScript Testing Patterns
```typescript
// SolidJS component testing with Vitest and Testing Library
import { render, screen, fireEvent } from '@solidjs/testing-library'
import { describe, expect, it, vi } from 'vitest'
import { GameCard, GameCardProps } from '../GameCard'

// Mock props factory
const createMockProps = (overrides: Partial<GameCardProps> = {}): GameCardProps => ({
  question: "What is the capital of France?",
  theme: "Geography",
  timeRemaining: 1800, // 30 minutes
  attemptsLeft: 3,
  onSubmitAnswer: vi.fn(),
  loading: false,
  ...overrides,
})

describe('GameCard', () => {
  describe('Rendering', () => {
    it('should render question and theme correctly', () => {
      const props = createMockProps()

      render(() => <GameCard {...props} />)

      expect(screen.getByText(props.question)).toBeInTheDocument()
      expect(screen.getByText(props.theme)).toBeInTheDocument()
    })
  })

  describe('User Interactions', () => {
    it('should call onSubmitAnswer when submit button is clicked', async () => {
      const props = createMockProps()
      const mockOnSubmitAnswer = vi.fn().mockResolvedValue(undefined)
      props.onSubmitAnswer = mockOnSubmitAnswer

      render(() => <GameCard {...props} />)

      const input = screen.getByPlaceholderText('Enter your answer')
      fireEvent.input(input, { target: { value: 'Paris' } })

      const submitButton = screen.getByRole('button', { name: 'Submit Answer' })
      fireEvent.click(submitButton)

      expect(mockOnSubmitAnswer).toHaveBeenCalledWith('Paris')
    })
  })
})
```
## Git Workflow
```bash
# Branch naming conventions
feature/add-game-session-management
bugfix/fix-timer-display-issue
hotfix/security-vulnerability-patch
refactor/improve-database-queries

# Commit message format
type(scope): description

# Types: feat, fix, docs, style, refactor, test, chore
# Examples:
feat(game): add session timeout handling
fix(auth): resolve JWT token validation issue
docs(api): update authentication endpoint documentation
test(services): add comprehensive game service tests
```

## Development Commands

### Backend Development
```bash
# Navigate to service directory first
cd backend/services/{service-name}

# Start service in development mode with hot reload
go run cmd/main.go

# Service ports are env-driven via shared bootstrap helpers:
# ADMIN_SERVICE_PORT, GAME_SESSION_PORT, GATEWAY_PORT,
# LEADERBOARD_PORT, QUESTION_BANK_PORT, USER_SERVICE_PORT

# Run tests for a specific service
go test ./... -v

# Run tests with coverage
go test ./... -cover

# Build service binary
go build -o bin/{service-name} cmd/main.go

# Generate Ent schemas (from service root)
go generate ./...

# Lint Go code
golangci-lint run

# Format Go code  
go fmt ./...
goimports -w .

# Update go.mod of all services
find . -type f -name "*.mod" -printf "%h\0" | sort -zu | xargs -0 -I{} sh -c 'cd "{}" && go mod tidy'

# Run all backend tests
go test  $(go list -f '{{.Dir}}/...' -m | xargs)

# Go vet all backend code
go vet  $(go list -f '{{.Dir}}/...' -m | xargs)

# Lint all backend code
golangci-lint run  $(go list -f '{{.Dir}}/...' -m | xargs)
```

### Development Environment
```bash
# Start development stack with Docker Compose
cd infrastructure/dev
docker-compose up -d

# This starts:
# - PostgreSQL database (port 5432)
# - Redis cache (port 6379) 
# - Zitadel auth server (port 8080)
```

### Frontend Development
Note: This project uses Yarn with `nodeLinker: node-modules`. PnP files like `.pnp.cjs` and `.pnp.loader.mjs` are not used.
Status: `Web` commands are implemented. `Tauri cross-platform` commands are planned and require a future `frontend/apps/cross-platform` workspace.
```bash
# Web application
cd frontend
yarn install
yarn dev             # Start web development server (SolidJS)
yarn build           # Build all frontend workspaces
yarn test            # Run Vitest suites
yarn lint            # ESLint
yarn format:check    # Prettier check

# Cross-platform packaging with Tauri (desktop/mobile)
cd frontend/apps/cross-platform
yarn tauri dev       # Run Tauri app with embedded web UI
yarn tauri build     # Build release bundles
```