use crate::schema;
use microrm::prelude::*;
use ring::signature::Ed25519KeyPair;
use sha2::Digest;
use std::collections::HashMap;

pub struct CertStore<'a> {
    db: &'a microrm::DB,
    qi: microrm::QueryInterface<'a>,
    keys: HashMap<String, Ed25519KeyPair>,
}

impl<'a> CertStore<'a> {
    pub fn new(db: &'a microrm::DB) -> Self {
        Self {
            db,
            qi: db.query_interface(),
            keys: HashMap::new(),
        }
    }

    fn realm_id(&self, realm_name: &str) -> Option<schema::RealmID> {
        self.qi
            .get()
            .by(schema::Realm::Shortname, realm_name)
            .one()
            .expect("couldn't query db")
            .map(|x| x.id())
    }

    pub fn generate_in(&self, realm_name: &str) -> Result<String, &'static str> {
        let mut rng = ring::rand::SystemRandom::new();
        let sign_generated = Ed25519KeyPair::generate_pkcs8(&mut rng);

        let realm_id = self.realm_id(realm_name).ok_or("Failed to find realm")?;

        if let Err(_) = sign_generated {
            return Err("Failed to generate key");
        }
        let sign_generated = sign_generated.unwrap();

        let keydata = sign_generated.as_ref().to_owned();

        let mut key_hasher = sha2::Sha256::new();
        key_hasher.update(&keydata);
        let mut key_id = base64::encode(key_hasher.finalize());
        key_id.truncate(16);

        self.qi
            .add(&schema::Key {
                realm: realm_id,
                key_id: key_id.clone(),
                keydata,
            })
            .expect("Couldn't add key");

        Ok(key_id)
    }
}

pub fn inspect(db: &microrm::DB, realm_name: &str) {
    let qi = db.query_interface();
    let cs = CertStore::new(db);
    println!("Certstore loaded.");
    let realm = qi
        .get()
        .by(schema::Realm::Shortname, realm_name)
        .one()
        .expect("couldn't query db");
    if realm.is_none() {
        println!("No such realm {}", realm_name);
        return;
    }
    let realm = realm.unwrap();

    println!("Retrieving keys for {} realm...", realm_name);
    let keys = qi
        .get()
        .by(schema::Key::Realm, &realm.id())
        .all()
        .expect("Can get keys");
    for key in keys {
        println!("- [{:20}]", key.key_id);
    }
}

pub fn generate(db: &microrm::DB, realm_name: &str) {
    let qi = db.query_interface();
    let cs = CertStore::new(db);
    if let Err(e) = cs.generate_in(realm_name) {
        println!("Failed to generate key: {}", e);
    }
}