/**
 * A Wrapper for Forge's AES-CBC encryption
 */
var AesCBC = function(forge) {
	'use strict';

	var utl = forge.util;

	/**
	 * Encrypt a String using AES-CBC-Pkcs7 using the provided keysize (e.g. 128, 256)
	 * @param plaintext [String] The input string in UTF-16
	 * @param key [String] The base64 encoded key
	 * @param iv [String] The base64 encoded IV
	 * @return [String] The base64 encoded ciphertext
	 */
	this.encrypt = function(plaintext, key, iv) {
		// decode args to utf8 and encrypt
		var cipher = forge.aes.createEncryptionCipher(utl.decode64(key));
		cipher.start(utl.decode64(iv));
		cipher.update(utl.createBuffer(utl.encodeUtf8(plaintext)));
		cipher.finish();

		// encode to base64
		return utl.encode64(cipher.output.getBytes());
	};

	/**
	 * Decrypt a String using AES-CBC-Pkcs7 using the provided keysize (e.g. 128, 256)
	 * @param ciphertext [String] The base64 encoded ciphertext
	 * @param key [String] The base64 encoded key
	 * @param iv [String] The base64 encoded IV
	 * @return [String] The decrypted plaintext in UTF-16
	 */
	this.decrypt = function(ciphertext, key, iv) {
		// decode args input to utf8 decrypt
		var cipher = forge.aes.createDecryptionCipher(utl.decode64(key));
		cipher.start(utl.decode64(iv));
		cipher.update(utl.createBuffer(utl.decode64(ciphertext)));
		cipher.finish();

		// decode to utf16
		return utl.decodeUtf8(cipher.output.getBytes());
	};

};

if (typeof module !== 'undefined' && module.exports) {
	module.exports = AesCBC;
} else {
	app.crypto.AesCBC = AesCBC;
}