# Email Verification System - Complete Implementation

## Overview

The application now has a complete email verification system for both **Sign Up** and **Forgot Password** flows. Both systems use **Resend** to send verification codes to real email addresses (Gmail, Yahoo, etc.) for security.

---

## 🔐 Sign Up Email Verification

### Flow:
1. **Step 1: User Details**
   - User enters: Username, Email, Password, Confirm Password
   - Clicks "Send Verification Code"
   - System validates email format and checks if email already exists

2. **Step 2: Email Verification**
   - System sends a 6-digit code to the user's email via Resend
   - User enters the code
   - System verifies the code
   - If valid, account is created

### Files:
- `app/register/page.tsx` - 2-step registration UI
- `app/api/auth/send-verification-code/route.ts` - Sends verification code
- `app/api/auth/verify-code/route.ts` - Verifies the code
- `app/api/auth/verify-token/route.ts` - Validates token before registration
- `contexts/supabase-auth-context.tsx` - Handles registration with verification

---

## 🔑 Forgot Password Email Verification

### Flow:
1. **Step 1: Enter Email**
   - User enters their verified email address
   - Clicks "Send Verification Code"
   - System checks if user exists (for security, doesn't reveal if email exists)

2. **Step 2: Verify Code**
   - System sends a 6-digit reset code to the user's email via Resend
   - User enters the code
   - System verifies the code
   - If valid, redirects to reset password page

3. **Step 3: Reset Password**
   - User enters new password and confirms it
   - Password is updated in both custom users table and Supabase Auth

### Files:
- `app/forgot-password/page.tsx` - 2-step forgot password UI
- `app/reset-password/page.tsx` - Reset password form
- `app/api/auth/send-reset-code/route.ts` - Sends password reset code
- `app/api/auth/verify-reset-code/route.ts` - Verifies the reset code
- `app/api/auth/reset-password/route.ts` - Updates password after verification

---

## 📧 Email Service Configuration

### Required Environment Variables:

Add to `.env.local`:

```env
# Resend Email Service
RESEND_API_KEY=re_your_actual_api_key_here
RESEND_FROM_EMAIL=BUILDMATE <onboarding@resend.dev>
```

### Getting Your Resend API Key:

1. Go to [https://resend.com/api-keys](https://resend.com/api-keys)
2. Sign in or create a free account
3. Click "Create API Key"
4. Copy the key (starts with `re_`, 40+ characters)
5. Paste it in `.env.local`
6. **Restart your development server**

### Email Sending:

- **From Address**: Uses `onboarding@resend.dev` by default (Resend's pre-verified test domain)
- **To Address**: User's email (Gmail, Yahoo, Outlook, etc.)
- **Format**: HTML emails with professional styling
- **Security**: Codes expire in 10 minutes

---

## 🔒 Security Features

### Email Verification:
- ✅ Only real, verified email addresses can receive codes
- ✅ Codes are 6-digit random numbers
- ✅ Codes expire after 10 minutes
- ✅ Codes are single-use
- ✅ Email format validation (Gmail, Yahoo, etc.)

### Password Reset:
- ✅ Requires email verification before reset
- ✅ Reset tokens expire after 15 minutes
- ✅ Passwords are hashed with bcrypt (12 rounds)
- ✅ Updates both custom users table and Supabase Auth

### User Registration:
- ✅ Email must be verified before account creation
- ✅ Prevents duplicate email registration
- ✅ Email format validation
- ✅ Password strength requirements (minimum 6 characters)

---

## 🎨 UI Features

### Forgot Password Page:
- Clean 2-step flow with clear instructions
- Email input with validation
- Code input with 6-digit format
- Back button to return to email step
- Resend code option
- Success/error messages

### Sign Up Page:
- 2-step registration flow
- Username, email, password inputs
- Terms and conditions checkbox
- Code verification step
- Clear error messages

### Reset Password Page:
- New password and confirm password inputs
- Password visibility toggle
- Validation feedback
- Success message with auto-redirect

---

## 🚀 Usage

### For Users:

1. **Sign Up**:
   - Go to `/register`
   - Enter details → Click "Send Verification Code"
   - Check email → Enter code → Account created

2. **Forgot Password**:
   - Go to `/login` → Click "Forgot password?"
   - Enter email → Click "Send Verification Code"
   - Check email → Enter code → Reset password

### For Developers:

1. **Configure Resend**:
   - Get API key from Resend dashboard
   - Add to `.env.local`
   - Restart server

2. **Test Email Sending**:
   - Try registration or forgot password
   - Check terminal for logs
   - Check email inbox (and spam folder)

3. **Troubleshooting**:
   - If emails not sending, check:
     - API key is correct (not placeholder)
     - Server was restarted after adding API key
     - Email address is valid format
     - Check terminal for error messages

---

## 📝 Code Structure

### Verification Code Storage:
- Codes stored in memory (Map) with expiration
- In production, consider using Redis or database
- Automatic cleanup of expired codes

### Token System:
- Verification tokens generated after code verification
- Tokens valid for 15 minutes
- Single-use tokens for security

### Error Handling:
- Clear error messages for users
- Detailed logging for developers
- Graceful fallbacks in development mode

---

## ✅ Testing Checklist

- [ ] Sign up with Gmail address
- [ ] Sign up with Yahoo address
- [ ] Verify code is received in email
- [ ] Test code expiration (wait 10+ minutes)
- [ ] Test invalid code entry
- [ ] Forgot password with existing email
- [ ] Forgot password with non-existent email (should not reveal)
- [ ] Reset password after code verification
- [ ] Login with new password after reset

---

## 🔧 Troubleshooting

### "API key is invalid" Error:
- ✅ Check `.env.local` has correct API key (not placeholder)
- ✅ Restart development server
- ✅ Verify API key in Resend dashboard is active

### "Email not received":
- ✅ Check spam/junk folder
- ✅ Verify email address is correct
- ✅ Check terminal for email sending logs
- ✅ Ensure Resend API key is configured

### "Code expired":
- ✅ Request a new code (codes expire in 10 minutes)
- ✅ Check system time is correct

---

## 📚 Related Documentation

- `FIX_API_KEY.md` - How to fix Resend API key issues
- `SETUP_RESEND.md` - Detailed Resend setup guide
- `RESEND_GMAIL_SETUP.md` - Quick Gmail setup guide

---

## 🎯 Next Steps

For production:
1. Verify your own domain with Resend
2. Update `RESEND_FROM_EMAIL` to use your domain
3. Consider using Redis for code storage (instead of memory)
4. Add rate limiting to prevent abuse
5. Add email templates for better branding