#![no_std]
#![no_main]

use defmt::info;
use embassy_executor::Spawner;
use embassy_stm32::hash::*;
use embassy_stm32::{bind_interrupts, hash, peripherals, Config};
use embassy_time::Instant;
use hmac::{Hmac, Mac};
use sha2::{Digest, Sha256};
use {defmt_rtt as _, panic_probe as _};

type HmacSha256 = Hmac<Sha256>;

bind_interrupts!(struct Irqs {
    HASH_RNG => hash::InterruptHandler<peripherals::HASH>;
});

#[embassy_executor::main]
async fn main(_spawner: Spawner) -> ! {
    let config = Config::default();
    let p = embassy_stm32::init(config);

    let test_1: &[u8] = b"as;dfhaslfhas;oifvnasd;nifvnhasd;nifvhndlkfghsd;nvfnahssdfgsdafgsasdfasdfasdfasdfasdfghjklmnbvcalskdjghalskdjgfbaslkdjfgbalskdjgbalskdjbdfhsdfhsfghsfghfgh";
    let test_2: &[u8] = b"fdhalksdjfhlasdjkfhalskdjfhgal;skdjfgalskdhfjgalskdjfglafgadfgdfgdafgaadsfgfgdfgadrgsyfthxfgjfhklhjkfgukhulkvhlvhukgfhfsrghzdhxyfufynufyuszeradrtydyytserr";

    let mut hw_hasher = Hash::new(p.HASH, p.DMA2_CH7, Irqs);

    let hw_start_time = Instant::now();

    // Compute a digest in hardware.
    let mut context = hw_hasher.start(Algorithm::SHA256, DataType::Width8, None);
    hw_hasher.update(&mut context, test_1).await;
    hw_hasher.update(&mut context, test_2).await;
    let mut hw_digest: [u8; 32] = [0; 32];
    hw_hasher.finish(context, &mut hw_digest).await;

    let hw_end_time = Instant::now();
    let hw_execution_time = hw_end_time - hw_start_time;

    let sw_start_time = Instant::now();

    // Compute a digest in software.
    let mut sw_hasher = Sha256::new();
    sw_hasher.update(test_1);
    sw_hasher.update(test_2);
    let sw_digest = sw_hasher.finalize();

    let sw_end_time = Instant::now();
    let sw_execution_time = sw_end_time - sw_start_time;

    info!("Hardware Digest: {:?}", hw_digest);
    info!("Software Digest: {:?}", sw_digest[..]);
    info!("Hardware Execution Time: {:?}", hw_execution_time);
    info!("Software Execution Time: {:?}", sw_execution_time);
    assert_eq!(hw_digest, sw_digest[..]);

    let hmac_key: [u8; 64] = [0x55; 64];

    // Compute HMAC in hardware.
    let mut sha256hmac_context = hw_hasher.start(Algorithm::SHA256, DataType::Width8, Some(&hmac_key));
    hw_hasher.update(&mut sha256hmac_context, test_1).await;
    hw_hasher.update(&mut sha256hmac_context, test_2).await;
    let mut hw_hmac: [u8; 32] = [0; 32];
    hw_hasher.finish(sha256hmac_context, &mut hw_hmac).await;

    // Compute HMAC in software.
    let mut sw_mac = HmacSha256::new_from_slice(&hmac_key).unwrap();
    sw_mac.update(test_1);
    sw_mac.update(test_2);
    let sw_hmac = sw_mac.finalize().into_bytes();

    info!("Hardware HMAC: {:?}", hw_hmac);
    info!("Software HMAC: {:?}", sw_hmac[..]);
    assert_eq!(hw_hmac, sw_hmac[..]);

    loop {}
}