Add share pin

components/Landing.tsx

@@ -67,6 +67,12 @@ export const Landing: React.FC<LandingProps> = ({ onGenerate, onCreateManual, on
   const [pin, setPin] = useState(initialPin || '');
   const [name, setName] = useState('');
   
+  useEffect(() => {
+    if (initialPin) {
+      setPin(initialPin);
+    }
+  }, [initialPin]);
+  
   const modalParam = searchParams.get('modal');
   const libraryOpen = modalParam === 'library';
   const importOpen = modalParam === 'import';

components/Lobby.tsx

@@ -1,8 +1,9 @@
-import React from 'react';
+import React, { useState } from 'react';
 import { Player } from '../types';
 import { motion, AnimatePresence } from 'framer-motion';
-import { Sparkles, User, X } from 'lucide-react';
+import { Sparkles, User, X, Link, Check } from 'lucide-react';
 import { PlayerAvatar } from './PlayerAvatar';
+import toast from 'react-hot-toast';
 
 interface LobbyProps {
   quizTitle: string;
@@ -20,15 +21,36 @@ export const Lobby: React.FC<LobbyProps> = ({ quizTitle, players, gamePin, role,
   const hostPlayer = players.find(p => p.id === 'host');
   const realPlayers = players.filter(p => p.id !== 'host');
   const currentPlayer = currentPlayerId ? players.find(p => p.id === currentPlayerId) : null;
+  const [linkCopied, setLinkCopied] = useState(false);
+
+  const copyJoinLink = async () => {
+    if (!gamePin) return;
+    const joinUrl = `${window.location.origin}/play/${gamePin}`;
+    await navigator.clipboard.writeText(joinUrl);
+    setLinkCopied(true);
+    toast.success('Join link copied!');
+    setTimeout(() => setLinkCopied(false), 2000);
+  };
 
   return (
     <div className="flex flex-col h-screen p-4 md:p-6 overflow-hidden">
       <header className="flex flex-col md:flex-row justify-between items-center bg-white/10 p-4 md:p-6 rounded-2xl md:rounded-[2rem] backdrop-blur-md mb-4 md:mb-8 gap-3 md:gap-6 border-4 border-white/20 shadow-xl shrink-0">
         <div className="flex flex-col items-center md:items-start">
             <span className="text-white/80 font-bold uppercase tracking-widest text-xs md:text-sm mb-1">Game PIN</span>
+            <div className="flex items-center gap-2">
                 <div className="text-4xl md:text-6xl font-black bg-white text-theme-primary px-6 md:px-8 py-1 md:py-2 rounded-full shadow-[0_6px_0_rgba(0,0,0,0.2)] tracking-wider">
                     {gamePin}
                 </div>
+                {isHost && (
+                    <button
+                        onClick={copyJoinLink}
+                        className="bg-white/20 hover:bg-white/30 p-3 rounded-full transition-all active:scale-95"
+                        title="Copy join link"
+                    >
+                        {linkCopied ? <Check size={24} className="text-green-400" /> : <Link size={24} />}
+                    </button>
+                )}
+            </div>
         </div>
         
         <div className="text-center hidden md:block">

tests/components/Lobby.test.tsx

@@ -0,0 +1,229 @@
+import React from 'react';
+import { render, screen, waitFor } from '@testing-library/react';
+import userEvent from '@testing-library/user-event';
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+import { Lobby } from '../../components/Lobby';
+
+vi.mock('react-hot-toast', () => ({
+  default: {
+    success: vi.fn(),
+    error: vi.fn(),
+  },
+}));
+
+vi.mock('framer-motion', () => ({
+  motion: {
+    div: ({ children, ...props }: React.PropsWithChildren<Record<string, unknown>>) => <div {...props}>{children}</div>,
+  },
+  AnimatePresence: ({ children }: React.PropsWithChildren) => <>{children}</>,
+}));
+
+describe('Lobby', () => {
+  const defaultProps = {
+    quizTitle: 'Test Quiz',
+    players: [],
+    gamePin: 'ABC123',
+    role: 'HOST' as const,
+    onStart: vi.fn(),
+    onEndGame: vi.fn(),
+  };
+
+  beforeEach(() => {
+    vi.clearAllMocks();
+    Object.defineProperty(window, 'location', {
+      value: { origin: 'http://localhost:5173' },
+      writable: true,
+    });
+  });
+
+  describe('copy join link', () => {
+    it('shows copy link button for host', () => {
+      render(<Lobby {...defaultProps} />);
+      
+      expect(screen.getByTitle('Copy join link')).toBeInTheDocument();
+    });
+
+    it('does not show copy link button for client', () => {
+      render(<Lobby {...defaultProps} role="CLIENT" />);
+      
+      expect(screen.queryByTitle('Copy join link')).not.toBeInTheDocument();
+    });
+
+    it('copies join URL to clipboard when clicked', async () => {
+      const user = userEvent.setup();
+      render(<Lobby {...defaultProps} />);
+      
+      const copyButton = screen.getByTitle('Copy join link');
+      expect(copyButton.querySelector('.lucide-link')).toBeInTheDocument();
+      
+      await user.click(copyButton);
+      
+      await waitFor(() => {
+        expect(copyButton.querySelector('.lucide-check')).toBeInTheDocument();
+      });
+    });
+
+    it('shows success toast when link is copied', async () => {
+      const toast = await import('react-hot-toast');
+      const user = userEvent.setup();
+      render(<Lobby {...defaultProps} />);
+      
+      await user.click(screen.getByTitle('Copy join link'));
+      
+      await waitFor(() => {
+        expect(toast.default.success).toHaveBeenCalledWith('Join link copied!');
+      });
+    });
+
+    it('shows checkmark after copying link', async () => {
+      const user = userEvent.setup();
+      render(<Lobby {...defaultProps} gamePin="XYZ789" />);
+      
+      const copyButton = screen.getByTitle('Copy join link');
+      
+      await user.click(copyButton);
+      
+      await waitFor(() => {
+        expect(copyButton.querySelector('.lucide-check')).toBeInTheDocument();
+      });
+    });
+  });
+
+  describe('display', () => {
+    it('displays game PIN', () => {
+      render(<Lobby {...defaultProps} />);
+      
+      expect(screen.getByText('ABC123')).toBeInTheDocument();
+    });
+
+    it('displays quiz title on larger screens', () => {
+      render(<Lobby {...defaultProps} />);
+      
+      expect(screen.getByText('Test Quiz')).toBeInTheDocument();
+    });
+
+    it('displays player count', () => {
+      const players = [
+        { id: '1', name: 'Player 1', score: 0, avatarSeed: 0.1 },
+        { id: '2', name: 'Player 2', score: 0, avatarSeed: 0.2 },
+      ];
+      render(<Lobby {...defaultProps} players={players} />);
+      
+      expect(screen.getByText('2')).toBeInTheDocument();
+    });
+
+    it('shows waiting message when no players have joined', () => {
+      render(<Lobby {...defaultProps} />);
+      
+      expect(screen.getByText('Waiting for players to join...')).toBeInTheDocument();
+    });
+
+    it('displays player names when players join', () => {
+      const players = [
+        { id: '1', name: 'Alice', score: 0, avatarSeed: 0.1 },
+        { id: '2', name: 'Bob', score: 0, avatarSeed: 0.2 },
+      ];
+      render(<Lobby {...defaultProps} players={players} />);
+      
+      expect(screen.getByText('Alice')).toBeInTheDocument();
+      expect(screen.getByText('Bob')).toBeInTheDocument();
+    });
+  });
+
+  describe('host controls', () => {
+    it('shows Start button for host', () => {
+      render(<Lobby {...defaultProps} />);
+      
+      expect(screen.getByRole('button', { name: 'Start' })).toBeInTheDocument();
+    });
+
+    it('disables Start button when no players', () => {
+      render(<Lobby {...defaultProps} />);
+      
+      expect(screen.getByRole('button', { name: 'Start' })).toBeDisabled();
+    });
+
+    it('enables Start button when players joined', () => {
+      const players = [{ id: '1', name: 'Player 1', score: 0, avatarSeed: 0.1 }];
+      render(<Lobby {...defaultProps} players={players} />);
+      
+      expect(screen.getByRole('button', { name: 'Start' })).not.toBeDisabled();
+    });
+
+    it('calls onStart when Start clicked', async () => {
+      const user = userEvent.setup();
+      const players = [{ id: '1', name: 'Player 1', score: 0, avatarSeed: 0.1 }];
+      render(<Lobby {...defaultProps} players={players} />);
+      
+      await user.click(screen.getByRole('button', { name: 'Start' }));
+      
+      expect(defaultProps.onStart).toHaveBeenCalled();
+    });
+
+    it('shows End Game button when onEndGame provided', () => {
+      render(<Lobby {...defaultProps} />);
+      
+      expect(screen.getByText('End Game')).toBeInTheDocument();
+    });
+
+    it('calls onEndGame when End Game clicked', async () => {
+      const user = userEvent.setup();
+      render(<Lobby {...defaultProps} />);
+      
+      await user.click(screen.getByText('End Game'));
+      
+      expect(defaultProps.onEndGame).toHaveBeenCalled();
+    });
+  });
+
+  describe('client view', () => {
+    it('shows waiting message for client', () => {
+      render(<Lobby {...defaultProps} role="CLIENT" />);
+      
+      expect(screen.getByText('Waiting for the host to start...')).toBeInTheDocument();
+    });
+
+    it('shows player name when currentPlayerId matches', () => {
+      const players = [
+        { id: 'player-1', name: 'My Name', score: 0, avatarSeed: 0.5 },
+      ];
+      render(
+        <Lobby 
+          {...defaultProps} 
+          role="CLIENT" 
+          players={players}
+          currentPlayerId="player-1"
+        />
+      );
+      
+      expect(screen.getByText('My Name')).toBeInTheDocument();
+    });
+
+    it('does not show Start button for client', () => {
+      render(<Lobby {...defaultProps} role="CLIENT" />);
+      
+      expect(screen.queryByRole('button', { name: 'Start' })).not.toBeInTheDocument();
+    });
+  });
+
+  describe('host participates mode', () => {
+    it('shows host in player list when hostParticipates is true', () => {
+      const players = [
+        { id: 'host', name: 'Host Player', score: 0, avatarSeed: 0.99 },
+      ];
+      render(<Lobby {...defaultProps} players={players} hostParticipates={true} />);
+      
+      expect(screen.getByText('Host Player')).toBeInTheDocument();
+      expect(screen.getByText('HOST')).toBeInTheDocument();
+    });
+
+    it('does not show waiting message when host participates and no other players', () => {
+      const players = [
+        { id: 'host', name: 'Host Player', score: 0, avatarSeed: 0.99 },
+      ];
+      render(<Lobby {...defaultProps} players={players} hostParticipates={true} />);
+      
+      expect(screen.queryByText('Waiting for players to join...')).not.toBeInTheDocument();
+    });
+  });
+});

tests/hooks/useGame.navigation.test.tsx

@@ -1279,6 +1279,51 @@ describe('OAuth Callback Handling', () => {
   });
 });
 
+describe('/play/:pin URL Join Flow', () => {
+  describe('Landing PIN sync (regression: PIN field empty on /play/:pin)', () => {
+    it('should sync local PIN state when initialPin prop changes after async load', () => {
+      let initialPin: string | null = null;
+      let localPin = initialPin || '';
+      
+      const syncPin = (newInitialPin: string | null) => {
+        if (newInitialPin) {
+          localPin = newInitialPin;
+        }
+      };
+      
+      initialPin = 'TESTPIN';
+      syncPin(initialPin);
+      
+      expect(localPin).toBe('TESTPIN');
+    });
+
+    it('should preserve user-typed PIN when initialPin becomes null', () => {
+      let localPin = 'USER_TYPED';
+      
+      const syncPin = (newInitialPin: string | null) => {
+        if (newInitialPin) {
+          localPin = newInitialPin;
+        }
+      };
+      
+      syncPin(null);
+      
+      expect(localPin).toBe('USER_TYPED');
+    });
+
+    it('should force JOIN mode when initialPin is provided via URL', () => {
+      const getModeFromUrl = (searchParams: URLSearchParams, initialPin?: string): 'HOST' | 'JOIN' => {
+        if (initialPin) return 'JOIN';
+        const modeParam = searchParams.get('mode');
+        return modeParam === 'host' ? 'HOST' : 'JOIN';
+      };
+      
+      const searchParams = new URLSearchParams('?mode=host');
+      expect(getModeFromUrl(searchParams, 'TESTPIN')).toBe('JOIN');
+    });
+  });
+});
+
 describe('State Sync with Async Data Loading', () => {
   describe('Settings modal data sync', () => {
     it('should update editingDefaultConfig when defaultConfig loads', () => {

tests/setup.tsx

@@ -1,7 +1,18 @@
 import React from 'react';
 import '@testing-library/jest-dom/vitest';
 import { cleanup } from '@testing-library/react';
-import { afterEach, vi } from 'vitest';
+import { afterEach, vi, beforeAll } from 'vitest';
+
+beforeAll(() => {
+  Object.defineProperty(navigator, 'clipboard', {
+    value: {
+      writeText: vi.fn().mockResolvedValue(undefined),
+      readText: vi.fn().mockResolvedValue(''),
+    },
+    writable: true,
+    configurable: true,
+  });
+});
 
 afterEach(() => {
   cleanup();