use aes::Aes128;
use block_modes::{BlockMode, Cbc};
use block_modes::block_padding::NoPadding;
use crate::error::{Result, Error};

type Aes128Cbc = Cbc<Aes128, NoPadding>;

pub const KEY_LEN: usize = 16;

pub fn encrypt (data: &[u8], key: [u8; KEY_LEN], iv: &[u8]) -> Result<Vec<u8>> {
    let cipher = Aes128Cbc::new_var(&key, &iv)?;

    return Ok(cipher.encrypt_vec(data));
}

pub fn decrypt(data: &[u8], key: [u8; KEY_LEN], iv: &[u8]) -> Result<Vec<u8>> {
    let cipher = Aes128Cbc::new_var(&key, &iv)?;

    let result = cipher.decrypt_vec(data);
    return match result {
        Ok(data) => {Ok(data)}
        Err(err) => {Err(Error::BlockModeError(err))}
    }
}

#[cfg(test)]
mod tests {
    use hex_literal::hex;

    #[test]
    fn encrypt() {
        let data = hex!("8db1f942f2d7cc82f6fa1486a30f8c12104a3b07e8eb77a7ac00000000000000");
        let key = hex!("e7aff3361c3e85347993c3219a87d24b");
        let iv = hex!("00000000000000000000000000000000");

        let data_enc = crate::crypto::cipher::aes::encrypt(&data, key, &iv).unwrap();

        let data_enc_expected = hex!("3c79d74a4969ba7123e5d8f6df24493112d221fd131a4617d0eda5d92ccc1b46");

        assert_eq!(data_enc, data_enc_expected);
    }
}