use sha2::{Sha256, Digest};
use rayon::prelude::*;

pub type PassKey = (String, Vec<u8>);

/// Hashes a text to a 32 bytes long key.
pub fn create_key(pw: String) -> Vec<u8> {
    let mut hasher = Sha256::default();
    hasher.input(pw);
    let result = hasher.result();
    let key = &result[0..8];
    return key.to_vec();
}

/// Maps a list of passwords to keys and returns a vector of pairs
pub fn map_to_keys(passwords: Vec<&String>) -> Vec<PassKey> {
    return passwords.par_iter().map(|pw| {
        let pw_str = (*pw).clone();
        (pw_str.clone(), create_key(pw_str))
    }).collect();
}

/// Creates a sha256 hashsum from the input data
pub fn sha_checksum(data: &Vec<u8>) -> Vec<u8> {
    let mut hasher = Sha256::default();
    hasher.input(data);
    let result = hasher.result();
    return result.to_vec();
}