# MIME Email Parser for Gmail Auto-Draft Extension

This component allows the Gmail Auto-Draft extension to parse raw MIME emails and extract their content properly.

## Features

- Parse raw MIME email content into structured data
- Extract headers, plain text content, and HTML content
- Support for multipart emails with nested boundaries
- Decode quoted-printable and base64 encoded content
- Extract sender, recipient, subject, and other metadata

## Usage

### In the Chrome Extension

1. **Paste Raw MIME Email**: In the extension UI, paste the raw MIME email content into the "Raw MIME Email" textarea.
2. **Generate Draft**: Click the "Auto-Draft with GPT" button to generate a response based on the parsed email.

### In Code

```javascript
// In content.js
const mimeContent = document.querySelector('.mime-content').value;
if (isMimeEmail(mimeContent)) {
  // Send to background script for parsing
  chrome.runtime.sendMessage({
    action: 'parseMimeEmail',
    mimeContent
  }, response => {
    if (response && response.success) {
      console.log('Parsed email:', response.emailData);
      // Use the parsed email data
    } else {
      console.error('Failed to parse email:', response.error);
    }
  });
}

// In background.js
chrome.runtime.onMessage.addListener((message, sender, sendResponse) => {
  if (message.action === 'parseMimeEmail') {
    try {
      const emailData = extractEmailThread(message.mimeContent);
      sendResponse({ success: true, emailData });
    } catch (error) {
      sendResponse({ success: false, error: error.message });
    }
    return true; // async
  }
});
```

## API

### `parseMimeEmail(mimeContent)`

Parses a raw MIME email into structured data.

**Parameters:**
- `mimeContent` (string): The raw MIME content of the email

**Returns:** Object with properties:
- `headers`: Object containing all email headers
- `textContent`: Plain text content of the email
- `htmlContent`: HTML content of the email (if available)
- `raw`: The original raw MIME content

### `extractEmailThread(mimeContent)`

Extracts structured data from a MIME email, including sender, recipient, and content.

**Parameters:**
- `mimeContent` (string): The raw MIME content of the email

**Returns:** Object with properties:
- `subject`: Email subject
- `date`: Email date
- `sender`: Object with `name` and `email` properties
- `recipient`: Object with `name` and `email` properties
- `content`: The email content (HTML if available, otherwise plain text)
- `cc`: CC recipients
- `bcc`: BCC recipients
- `messageId`: Message ID
- `inReplyTo`: In-Reply-To header
- `references`: References header
- `headers`: All email headers
- `raw`: The original raw MIME content

## Testing

You can test the parser using the `test_parser.js` script:

```bash
node test_parser.js
```

This will parse a sample MIME email and output the structured data.

## Limitations

- The parser handles common MIME formats but may not support all edge cases
- Very large emails may cause performance issues
- Some complex nested multipart structures may not be fully parsed