MetaMask Wallet Connection Implementation

This document outlines the implementation of real MetaMask wallet connection functionality for the PropChain application.

🎯 Task Overview

Objective: Replace the mock "Connect Wallet" button with real MetaMask integration that:

• Opens a modal when clicked
• Shows available wallets (MetaMask)
• Connects to MetaMask via window.ethereum
• Displays connected wallet address
• Handles MetaMask installation detection
• Stores connection state in app

📋 Implementation Steps

Step 1: TypeScript Types Setup

File: src/types/index.ts

Added wallet-related type definitions:

export interface WalletState {
  isConnected: boolean;
  address: string | null;
  isConnecting: boolean;
  error: string | null;
}

export interface EthereumProvider {
  request: (args: { method: string; params?: any[] }) => Promise<any>;
  on: (eventName: string, handler: (...args: any[]) => void) => void;
  removeListener: (
    eventName: string,
    handler: (...args: any[]) => void
  ) => void;
  isMetaMask?: boolean;
}

declare global {
  interface Window {
    ethereum?: EthereumProvider;
  }
}

Step 2: Wallet Context Creation

File: src/contexts/WalletContext.tsx

Created React Context for global wallet state management:

Key Features:

• MetaMask connection logic with window.ethereum.request()
• Error handling for user rejection and pending requests
• Event listeners for account/chain changes
• Address formatting utility
• Connection persistence across page refreshes

Core Functions:

const connectWallet = async () => {
  const accounts = await window.ethereum.request({
    method: "eth_requestAccounts",
  });
  // Handle connection success/error
};

const disconnectWallet = () => {
  // Clear local app state
};

Step 3: Wallet Modal Component

File: src/components/WalletModal/WalletModal.tsx

Built animated modal with two states:

Connected State:

• Shows wallet address (formatted as 0xabc...123)
• Disconnect and revoke access buttons
• Success animation with checkmark

Connection State:

• MetaMask installation detection
• Connection button with loading state
• Error messages with download links
• Clean, minimal design

Step 4: UI Component Updates

Navbar (src/components/Layout/Navbar.tsx):

• Integrated useWallet hook
• Button shows wallet address when connected
• Removed mock walletConnected prop

Dashboard (src/pages/DashboardPage.tsx):

• Replaced mock state with real wallet context
• Added disconnect functionality
• Real wallet address display

App (src/App.tsx):

• Wrapped with WalletProvider
• Added WalletModal component
• Simplified wallet connection handling

Step 5: Enhanced Features

Real-time Sync Detection:

• Listens for accountsChanged event
• Auto-updates when user disconnects in MetaMask
• Handles account switching automatically

Smart Error Handling:

• MetaMask not installed → Download link
• Connection rejected → User-friendly message
• Pending request → Clear error state

Animations:

• Modal entrance animations
• Button hover effects
• Loading spinners
• Smooth transitions

🔧 Technical Implementation

MetaMask Integration

// Check if MetaMask is installed
const isMetaMaskInstalled = Boolean(window.ethereum?.isMetaMask);

// Request connection
const accounts = await window.ethereum.request({
  method: "eth_requestAccounts",
});

// Listen for changes
window.ethereum.on("accountsChanged", handleAccountsChanged);

Error Handling

try {
  const accounts = await window.ethereum.request({
    method: "eth_requestAccounts",
  });
} catch (error: any) {
  if (error.code === 4001) {
    errorMessage = "Connection request was rejected";
  } else if (error.code === -32002) {
    errorMessage = "Connection request is already pending";
  }
}

Address Formatting

const formatAddress = (address: string): string => {
  return `${address.substring(0, 6)}...${address.substring(
    address.length - 4
  )}`;
};

🎨 User Experience

Connection Flow

1. User clicks "Connect Wallet"
2. Modal opens with MetaMask option
3. User clicks MetaMask button
4. MetaMask popup appears (first time only)
5. User approves connection
6. Wallet address appears in navbar
7. Modal shows connected state

Disconnect Flow

1. User clicks wallet address in navbar
2. Modal opens showing connected state
3. User can:
   • Disconnect: Clear app state only
   • Revoke: Get instructions to disconnect in MetaMask

Error States

• No MetaMask: Shows download link
• Rejected: Shows friendly error message
• Pending: Shows loading state

📁 Files Created/Modified

New Files

• src/contexts/WalletContext.tsx - Wallet state management
• src/components/WalletModal/WalletModal.tsx - Connection modal
• src/components/WalletModal/index.ts - Export file

Modified Files

• src/types/index.ts - Added wallet types
• src/components/Layout/Navbar.tsx - Integrated wallet context
• src/pages/DashboardPage.tsx - Real wallet data
• src/App.tsx - Added wallet provider and modal
• src/index.css - Custom animations

🧪 Testing

Test Scenarios

1. With MetaMask: Connect → Disconnect → Reconnect
2. Without MetaMask: Error handling → Download links
3. Account Switching: Automatic address updates
4. Network Changes: Proper page reload
5. Error Cases: Rejection, pending requests

Build Testing

npm run build
# ✓ Successfully builds with all features

🚀 Key Features Implemented

✅ Real MetaMask Integration

• Uses window.ethereum API
• Handles all MetaMask error codes
• Real-time state synchronization

✅ Professional UI

• Animated modal with smooth transitions
• Clean, modern design
• Intuitive user flows

✅ Robust Error Handling

• MetaMask installation detection
• User-friendly error messages
• Download links when needed

✅ State Management

• React Context for global state
• Connection persistence
• Event listener cleanup

🔄 Connection Behavior

App-level Disconnect vs MetaMask Disconnect:

• App disconnect: Clears local app state only
• MetaMask disconnect: Revokes site permissions completely

Why reconnection is automatic:

• MetaMask remembers trusted sites for better UX
• Users don't need to re-approve every time
• To fully revoke: MetaMask → Connected Sites → Disconnect

📝 Usage

For Users

1. Click "Connect Wallet" in navbar or dashboard
2. Select MetaMask from modal
3. Approve connection in MetaMask popup
4. Wallet address appears in navbar
5. Use disconnect to clear local connection

For Developers

import { useWallet } from "./contexts/WalletContext";

function MyComponent() {
  const { isConnected, address, connectWallet, disconnectWallet } = useWallet();

  return (
    <div>
      {isConnected ? (
        <p>Connected: {address}</p>
      ) : (
        <button onClick={connectWallet}>Connect Wallet</button>
      )}
    </div>
  );
}

🎯 Task Completion

✅ Modal opens when "Connect Wallet" clicked
✅ Shows MetaMask as available wallet
✅ Connects via window.ethereum API
✅ Displays connected wallet address
✅ Handles MetaMask installation detection
✅ Stores connection state in app
✅ Real-time sync with MetaMask changes
✅ Professional UI with animations
✅ Comprehensive error handling

The wallet connection task has been fully implemented with production-ready code, excellent user experience, and robust error handling.