//! Hybrid signatures (extensions/pq-signatures.md): the committed corpus is the generated one,
//! every case reaches the verdict it states, and §8 lists exactly the reasons the reference
//! reports, each of which the corpus gives.
#![cfg(feature = "pq_signatures")]

use wai::pq_sig::{corpus, Reason};

const CORPUS: &str = concat!(env!("CARGO_MANIFEST_DIR"), "/../pq-conformance/vectors.json");

/// Runs `f` on a thread with 1 MiB of stack, what Windows gives a program's main thread, on
/// which `wai_pq_vectors` generates and verifies this corpus. An unoptimised build needed 3.4 MiB
/// while each hybrid key held its expanded ML-DSA key by value (`pq_sig::HybridKey`), and about
/// 0.75 MiB since: one that outgrows 1 MiB again fails here, on every platform.
fn windows_main_stack<T: Send + 'static>(f: impl FnOnce() -> T + Send + 'static) -> T {
    std::thread::Builder::new().stack_size(1 << 20).spawn(f).expect("a thread").join().expect("the thread's result")
}
const EXTENSION: &str = concat!(env!("CARGO_MANIFEST_DIR"), "/../extensions/pq-signatures.md");

#[test]
fn the_committed_corpus_is_the_generated_one() {
    let committed = std::fs::read_to_string(CORPUS).expect("pq-conformance/vectors.json is committed");
    let generated = windows_main_stack(corpus::generate);
    assert_eq!(generated.len(), 1);
    assert_eq!(committed, generated[0].1, "pq-conformance/vectors.json is not what wai_pq_vectors gen writes");
}

#[test]
fn every_case_reaches_its_verdict() {
    let doc: serde_json::Value = serde_json::from_str(&std::fs::read_to_string(CORPUS).expect("the corpus")).expect("JSON");
    let n = doc["cases"].as_array().map_or(0, Vec::len);
    assert!(n >= 40, "{n} cases: a truncated corpus passes on nothing");
    let fails = windows_main_stack(move || corpus::run(&doc));
    assert!(fails.is_empty(), "{fails:#?}");
}

/// §8's table names exactly the reference's codes, in its order, and every one is given by a
/// case of the corpus.
#[test]
fn section_8_lists_the_codes() {
    let text = std::fs::read_to_string(EXTENSION).expect("the extension");
    let sec = text.split("\n## 8. ").nth(1).expect("§8").split("\n## ").next().expect("§8's end");
    let listed: Vec<&str> = sec
        .lines()
        .filter_map(|l| l.strip_prefix("| `"))
        .filter_map(|l| l.split('`').next())
        .collect();
    let codes: Vec<&str> = Reason::all().iter().map(|r| r.label()).collect();
    assert_eq!(listed, codes, "§8's table against the reference's codes");
    let corpus = std::fs::read_to_string(CORPUS).expect("the corpus");
    for c in codes {
        assert!(corpus.contains(&format!("reason={c}")), "no case gives {c}");
    }
}