//! M2 QR: roundtrip, garbage → Err, same-k rescan does not duplicate.

use std::sync::{Mutex, MutexGuard};

use onionwire::Store;
use onionwire::qr;

static ENV_LOCK: Mutex<()> = Mutex::new(());

struct TempHome {
    _dir: tempfile::TempDir,
    _guard: MutexGuard<'static, ()>,
}

impl TempHome {
    fn new() -> Self {
        let dir = tempfile::tempdir().expect("tempdir");
        let guard = ENV_LOCK.lock().expect("env lock");
        unsafe {
            std::env::set_var("ONIONWIRE_HOME", dir.path());
            std::env::set_var("ONIONWIRE_STORE_PASSPHRASE", "onionwire-test");
        }
        Self {
            _dir: dir,
            _guard: guard,
        }
    }
}

impl Drop for TempHome {
    fn drop(&mut self) {
        unsafe {
            std::env::remove_var("ONIONWIRE_HOME");
            std::env::remove_var("ONIONWIRE_STORE_PASSPHRASE");
        }
    }
}

fn v3onion(tag: &str) -> String {
    format!("{tag}.onion")
}

#[test]
fn encode_decode_roundtrip() {
    let _home = TempHome::new();
    let store = Store::open().expect("open");
    let me = store.self_identity().expect("self");
    let spk = [7u8; 32];
    let onion = v3onion("alice-locator");
    let raw = qr::encode(&me.identity_sk, &onion, &spk).expect("encode");
    assert!(raw.starts_with("onionwire:v1:k="), "payload prefix: {raw}");
    assert!(raw.contains(":o="));
    assert!(raw.contains(":spk="));
    assert!(raw.contains(":sig="));

    let p = qr::decode(&raw).expect("decode");
    assert_eq!(p.pubkey, me.identity_pk);
    assert_eq!(p.onion, onion);
    assert_eq!(p.signed_prekey, spk);
}

#[test]
fn garbage_is_err() {
    assert!(qr::decode("not a qr").is_err());
    assert!(qr::decode("").is_err());
    assert!(qr::decode("onionwire:v1:k=aa").is_err());
    assert!(qr::decode("🔥").is_err());
}

#[test]
fn missing_sig_is_err() {
    let _home = TempHome::new();
    let store = Store::open().expect("open");
    let me = store.self_identity().expect("self");
    let raw = qr::encode(&me.identity_sk, &v3onion("x"), &[1u8; 32]).expect("encode");
    let stripped = raw.rsplit_once(":sig=").expect("sig field").0;
    assert!(qr::decode(stripped).is_err());
    assert!(qr::decode(&format!("{stripped}:sig=")).is_err());
}

#[test]
fn bad_sig_is_err() {
    let _home = TempHome::new();
    let store = Store::open().expect("open");
    let me = store.self_identity().expect("self");
    let raw = qr::encode(&me.identity_sk, &v3onion("x"), &[1u8; 32]).expect("encode");
    let (head, sig) = raw.rsplit_once(":sig=").expect("sig field");
    let mut chars: Vec<char> = sig.chars().collect();
    let last = chars.last_mut().expect("sig chars");
    *last = if *last == '0' { '1' } else { '0' };
    let flipped: String = chars.into_iter().collect();
    assert!(qr::decode(&format!("{head}:sig={flipped}")).is_err());
}

#[test]
fn same_k_rescan_updates_onion_not_duplicate() {
    let _home = TempHome::new();
    let store = Store::open().expect("open");
    let me = store.self_identity().expect("self");
    let spk = [9u8; 32];
    let p1 = qr::decode(&qr::encode(&me.identity_sk, &v3onion("old"), &spk).unwrap()).unwrap();
    store
        .upsert_friend(&p1.pubkey, &p1.onion, Some("alice"))
        .unwrap();
    let p2 = qr::decode(&qr::encode(&me.identity_sk, &v3onion("new"), &spk).unwrap()).unwrap();
    store.upsert_friend(&p2.pubkey, &p2.onion, None).unwrap();
    assert_eq!(store.friend_count().unwrap(), 1);
    let f = store.get_friend(&p2.pubkey).unwrap().unwrap();
    assert_eq!(f.onion, v3onion("new"));
    assert_eq!(f.petname.as_deref(), Some("alice"));
}

#[test]
fn unknown_k_decode_does_not_insert() {
    let _home = TempHome::new();
    let store = Store::open().expect("open");
    let me = store.self_identity().expect("self");
    let raw = qr::encode(&me.identity_sk, &v3onion("x"), &[1u8; 32]).unwrap();
    let _p = qr::decode(&raw).unwrap();
    assert_eq!(store.friend_count().unwrap(), 0);
}