use crypto::stream::chacha20::ChaCha20;
use crypto::stream::{StreamEncrypt, StreamDecrypt};

struct Test<'a> {
    key: [u8; 32],
    nonce: [u8; 12],
    position: u32,
    plaintext: &'a [u8],
    ciphertext: &'a [u8],
}

const TESTS: [Test<'static>; 2] = [
    Test {
        key: [
            0, 0, 0, 0, 0, 0, 0, 0,
            0, 0, 0, 0, 0, 0, 0, 0,
            0, 0, 0, 0, 0, 0, 0, 0,
            0, 0, 0, 0, 0, 0, 0, 0,
        ],
        nonce: [
            0, 0, 0, 0, 0, 0,
            0, 0, 0, 0, 0, 0,
        ],
        position: 0,
        plaintext: &[0; 64],
        ciphertext: &[
            0x76, 0xb8, 0xe0, 0xad, 0xa0, 0xf1, 0x3d, 0x90, 0x40, 0x5d, 0x6a, 0xe5, 0x53, 0x86, 0xbd, 0x28,
            0xbd, 0xd2, 0x19, 0xb8, 0xa0, 0x8d, 0xed, 0x1a, 0xa8, 0x36, 0xef, 0xcc, 0x8b, 0x77, 0x0d, 0xc7,
            0xda, 0x41, 0x59, 0x7c, 0x51, 0x57, 0x48, 0x8d, 0x77, 0x24, 0xe0, 0x3f, 0xb8, 0xd8, 0x4a, 0x37,
            0x6a, 0x43, 0xb8, 0xf4, 0x15, 0x18, 0xa1, 0x1c, 0xc3, 0x87, 0xb6, 0x69, 0xb2, 0xee, 0x65, 0x86,
        ]
    },
    Test {
        key: [
            0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
            0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
            0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
            0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f
        ],
        nonce: [
            0, 0, 0, 0, 0, 0,
            0, 0x4a, 0, 0, 0, 0,
        ],
        position: 1,
        plaintext: b"Ladies and Gentlemen of the class of '99: If I could offer you only one tip for the future, sunscreen would be it.",
        ciphertext: &[
            0x6e, 0x2e, 0x35, 0x9a, 0x25, 0x68, 0xf9, 0x80, 0x41, 0xba, 0x07, 0x28, 0xdd, 0x0d, 0x69, 0x81,
            0xe9, 0x7e, 0x7a, 0xec, 0x1d, 0x43, 0x60, 0xc2, 0x0a, 0x27, 0xaf, 0xcc, 0xfd, 0x9f, 0xae, 0x0b,
            0xf9, 0x1b, 0x65, 0xc5, 0x52, 0x47, 0x33, 0xab, 0x8f, 0x59, 0x3d, 0xab, 0xcd, 0x62, 0xb3, 0x57,
            0x16, 0x39, 0xd6, 0x24, 0xe6, 0x51, 0x52, 0xab, 0x8f, 0x53, 0x0c, 0x35, 0x9f, 0x08, 0x61, 0xd8,
            0x07, 0xca, 0x0d, 0xbf, 0x50, 0x0d, 0x6a, 0x61, 0x56, 0xa3, 0x8e, 0x08, 0x8a, 0x22, 0xb6, 0x5e,
            0x52, 0xbc, 0x51, 0x4d, 0x16, 0xcc, 0xf8, 0x06, 0x81, 0x8c, 0xe9, 0x1a, 0xb7, 0x79, 0x37, 0x36,
            0x5a, 0xf9, 0x0b, 0xbf, 0x74, 0xa3, 0x5b, 0xe6, 0xb4, 0x0b, 0x8e, 0xed, 0xf2, 0x78, 0x5e, 0x42,
            0x87, 0x4d,
        ]
    }
];

#[test]
fn encryption() {
    for test in &TESTS {
        let mut cipher = ChaCha20::init(&test.key[..], &test.nonce[..], test.position);
        let mut buf = vec![0; test.plaintext.len()];

        cipher.encrypt_stream(test.plaintext, &mut buf[..]);
        assert_eq!(test.ciphertext, &buf[..]);
    }
}

#[test]
fn decryption() {
    for test in &TESTS {
        let mut cipher = ChaCha20::init(&test.key[..], &test.nonce[..], test.position);
        let mut buf = vec![0; test.plaintext.len()];

        cipher.decrypt_stream(test.ciphertext, &mut buf[..]);
        assert_eq!(test.plaintext, &buf[..]);
    }
}