# POP to IMAP Importer

A Rust application that downloads emails from a POP3 server and imports them into an IMAP server's INBOX.

## Features

- **POP3 to IMAP Migration**: Downloads all emails from a POP3 server and imports them to IMAP
- **IMAP Email Normalization**: Fix existing malformed emails already in your IMAP inbox
- Secure TLS connections
- Environment-based configuration
- Automatic email header normalization (RFC 5322 compliance)
  - Fixes improperly formatted header continuation lines
  - Ensures continuation lines start with proper whitespace
- Safe operation with dry-run mode and confirmation prompts

## Setup

1. Copy `.env.example` to `.env`:

   ```bash
   cp .env.example .env
   ```

2. Edit `.env` with your server credentials:

   ```env
   # POP3 Source Server Configuration
   POP3_HOST=pop.example.com
   POP3_PORT=995
   POP3_USERNAME=your_pop3_username
   POP3_PASSWORD=your_pop3_password

   # IMAP Destination Server Configuration
   IMAP_HOST=imap.example.com
   IMAP_PORT=993
   IMAP_USERNAME=your_imap_username
   IMAP_PASSWORD=your_imap_password
   ```

## Usage

### POP3 to IMAP Migration

Run the main importer to migrate emails from POP3 to IMAP:

```bash
cargo run --bin pop-to-imap
# or in release mode
cargo run --release --bin pop-to-imap
```

### Normalize Existing IMAP Emails

If you already have malformed emails in your IMAP inbox, use the normalization tool:

```bash
# Dry run to see what would be changed
cargo run --release --bin normalize-imap -- --dry-run

# Actually normalize the emails (will prompt for confirmation)
cargo run --release --bin normalize-imap

# Skip confirmation prompt
cargo run --release --bin normalize-imap --yes
```

**Note:** The normalize-imap tool will:

1. Fetch all emails from your IMAP INBOX
2. Analyze which emails have malformed headers
3. Show you a summary of what needs to be fixed
4. Delete and re-import only the emails that need normalization
5. Keep emails that are already RFC 5322 compliant unchanged