//! Cryptor module
//!
//! This module contains the [`Cryptor`] trait which is used to implement
//! encryption and decryption of published data.

use pubnub::core::error::PubNubError;
use std::fmt::Debug;

/// This trait is used to encrypt and decrypt messages sent to the
/// [`PubNub API`].
///
/// It is used by the [`dx`] modules to encrypt messages sent to PubNub and
/// returned by the [`PubNub API`].
///
/// To implement this trait, you must provide `encrypt` and `decrypt` methods
/// that takes a `&[u8]` and returns a `Result<Vec<u8>, PubNubError>`.
///
/// You can implement this trait for your own types, or use one of the provided
/// features to use a crypto library.
/// When you use this trait to make your own crypto, make sure that other SDKs
/// use the same encryption and decryption algorithms.
///
/// # Examples
/// ```
/// use pubnub::core::{Cryptor, error::PubNubError};
///
/// #[derive(Debug)]
/// struct MyCryptor;
///
/// impl Cryptor for MyCryptor {
///     fn encrypt(&self, source: Vec<u8>) -> Result<Vec<u8>, PubNubError> {
///         // Encrypt provided data here
///         Ok(vec![])
///     }
///
///     fn decrypt(&self, source: Vec<u8>) -> Result<Vec<u8>, PubNubError> {
///         // Decrypt provided data here
///         Ok(vec![])
///     }
/// }
/// ```
///
/// [`dx`]: ../dx/index.html
/// [`PubNub API`]: https://www.pubnub.com/docs
pub trait Cryptor: Debug + Send + Sync {
    /// Decrypt provided data.
    ///
    /// # Errors
    /// Should return an [`PubNubError::Encryption`] if provided data can't
    /// be encrypted or underlying cryptor misconfigured.
    fn encrypt(&self, source: Vec<u8>) -> Result<Vec<u8>, PubNubError>;

    /// Decrypt provided data.
    ///
    /// # Errors
    /// Should return an [`PubNubError::Decryption`] if provided data can't
    /// be decrypted or underlying cryptor misconfigured.
    fn decrypt(&self, source: Vec<u8>) -> Result<Vec<u8>, PubNubError>;
}