use std::error::Error;
use aes_gcm::{Aes256Gcm, KeyInit, Nonce};
use aes_gcm::aead::{Aead, Payload};
use rand::Rng;
use trifid_pki::rand_core::OsRng;
use crate::config::TrifidConfig;

pub fn get_cipher_from_config(config: &TrifidConfig) -> Result<Aes256Gcm, Box<dyn Error>> {
    let key_slice = hex::decode(&config.crypto.data_encryption_key)?;
    Ok(Aes256Gcm::new_from_slice(&key_slice)?)
}

pub fn encrypt_with_nonce(plaintext: &[u8], nonce: [u8; 12], cipher: &Aes256Gcm) -> Result<Vec<u8>, aes_gcm::Error> {
    let nonce = Nonce::from_slice(&nonce);
    let ciphertext = cipher.encrypt(nonce, plaintext)?;
    Ok(ciphertext)
}

pub fn decrypt_with_nonce(ciphertext: &[u8], nonce: [u8; 12], cipher: &Aes256Gcm) -> Result<Vec<u8>, aes_gcm::Error> {
    let nonce = Nonce::from_slice(&nonce);
    let plaintext = cipher.decrypt(nonce, Payload::from(ciphertext))?;
    Ok(plaintext)
}

pub fn generate_random_iv() -> [u8; 12] {
    OsRng.gen()
}