# Advanced Cipher

## Overview

`advanced-cipher` is a sophisticated encryption library providing robust, multi-layer encryption with advanced key derivation techniques.

## Features

- 256-bit encryption strength
- Multi-stage key derivation
- Complex bit-level transformations
- Secure encryption and decryption

## Installation

```bash
npm install advanced-cipher
```

## Usage

```javascript
import AdvancedCipher from 'advanced-cipher';

// Create cipher instance with a secret key
const cipher = new AdvancedCipher('YourSecretKey123!@#');

// Encrypt message
const encrypted = cipher.encrypt('Hello, Secure World!');

// Decrypt message
const decrypted = cipher.decrypt(encrypted);
```

## Security Details

- **Bit Level**: 256-bit
- **Key Derivation**: PBKDF2-inspired multi-iteration transformation
- **Encryption Layers**: 
  1. XOR-based encryption
  2. Bit rotation
  3. Iteration-dependent obfuscation

## API

### `new AdvancedCipher(secretKey, [iterations])`
- `secretKey` (required): A string of at least 12 characters
- `iterations` (optional): Number of key derivation iterations (default: 10000)

### `encrypt(plaintext)`
Encrypts the input text and returns a Base64 encoded string.

### `decrypt(ciphertext)`
Decrypts the Base64 encoded ciphertext and returns the original plaintext.

## License

MIT