//! Key release (extensions/key-release.md): the committed corpus `live-conformance/keys/`
//! regenerates byte for byte from its fixed seeds, holds no other file, every case in it gets
//! the outcome it states, and the extension's §11 lists exactly the reasons the reference
//! reports. The generator itself asserts that the corpus gives every one of them.
#![cfg(feature = "key_release")]

use std::collections::BTreeMap;
use std::path::PathBuf;
use wai::key_release::{corpus, Decision, DeliveryKind, Reason, Scheme};

fn wai_dir() -> PathBuf {
    PathBuf::from(env!("CARGO_MANIFEST_DIR")).join("..")
}

fn committed() -> BTreeMap<String, String> {
    let dir = wai_dir().join("live-conformance/keys");
    std::fs::read_dir(&dir)
        .expect("the committed corpus")
        .flatten()
        .map(|e| (e.file_name().to_string_lossy().into_owned(), e.path()))
        .filter(|(n, _)| n != "README.md")
        .map(|(n, p)| (n, std::fs::read_to_string(p).expect("a text file")))
        .collect()
}

#[test]
fn the_committed_corpus_regenerates_from_its_seeds() {
    let files = committed();
    let generated: BTreeMap<String, String> = corpus::generate().into_iter().collect();
    let extra: Vec<&String> = files.keys().filter(|k| !generated.contains_key(*k)).collect();
    let missing: Vec<&String> = generated.keys().filter(|k| !files.contains_key(*k)).collect();
    let differ: Vec<&String> = generated.iter().filter(|(k, v)| files.get(*k).is_some_and(|f| f != *v)).map(|(k, _)| k).collect();
    assert!(extra.is_empty() && missing.is_empty() && differ.is_empty(), "extra {extra:?}, missing {missing:?}, differ {differ:?}: run `wai_key_release_vectors gen`");
}

#[test]
fn every_case_gets_its_stated_outcome() {
    let fails = corpus::verify(&committed());
    assert!(fails.is_empty(), "{}", fails.join("\n"));
}

/// §11 of the extension lists exactly the codes `Reason::ALL` has, each once, in order.
#[test]
fn the_extension_lists_the_reasons() {
    let text = std::fs::read_to_string(wai_dir().join("extensions/key-release.md")).expect("the extension");
    let at = text.find("\n## 11. Reasons").expect("a §11");
    let end = text[at + 1..].find("\n## ").map_or(text.len(), |e| at + 1 + e);
    let listed: Vec<String> =
        text[at..end].lines().filter(|l| l.starts_with("| `")).filter_map(|l| l.split('`').nth(1).map(String::from)).collect();
    let want: Vec<String> = Reason::ALL.iter().map(|r| r.code().to_string()).collect();
    assert_eq!(listed, want, "§11's table and Reason::ALL differ");
}

/// The rows of the table under heading `head`, up to the next heading, split on `|`.
fn rows(head: &str) -> Vec<Vec<String>> {
    let text = std::fs::read_to_string(wai_dir().join("extensions/key-release.md")).expect("the extension");
    let at = text.find(&format!("\n{head}\n")).unwrap_or_else(|| panic!("a heading {head}"));
    let body = &text[at + head.len() + 2..];
    let end = body.find("\n#").unwrap_or(body.len());
    body[..end]
        .lines()
        .filter(|l| l.starts_with("| ") && !l.starts_with("| ---") && !l.starts_with("|---"))
        .skip(1)
        .map(|l| l.trim_matches('|').split('|').map(|c| c.trim().trim_matches('`').to_string()).collect())
        .collect()
}

/// §3.1, §3.2 and §7.2 give each scheme, delivery and decision the code and label the
/// reference writes, and no other.
#[test]
fn the_extension_tables_are_the_reference_codes() {
    let schemes: Vec<(String, String)> = rows("### 3.1 Schemes").iter().map(|r| (r[0].clone(), r[1].clone())).collect();
    let want: Vec<(String, String)> = Scheme::ALL.iter().map(|s| (s.code().to_string(), s.label().to_string())).collect();
    assert_eq!(schemes, want, "§3.1");
    let deliveries: Vec<(String, String)> = rows("### 3.2 Key deliveries").iter().map(|r| (r[0].clone(), r[1].clone())).collect();
    let want: Vec<(String, String)> = DeliveryKind::ALL.iter().map(|d| (d.code().to_string(), d.label().to_string())).collect();
    assert_eq!(deliveries, want, "§3.2");
    // §7.2's fourteen, and the four of §14.4 that only an entitlement with rules reaches.
    let mut decisions: Vec<(String, String)> = rows("### 7.2 The checks, in order").iter().chain(rows("### 14.4 The checks").iter()).map(|r| (r[1].clone(), r[2].clone())).collect();
    assert_eq!(rows("### 14.4 The checks").iter().map(|r| r[1].clone()).collect::<Vec<_>>(), Decision::ALL.iter().filter(|d| d.of_rules()).map(|d| d.label().to_string()).collect::<Vec<_>>(), "§14.4");
    decisions.sort();
    let mut want: Vec<(String, String)> = Decision::ALL.iter().map(|d| (d.label().to_string(), d.code().to_string())).collect();
    want.sort();
    assert_eq!(decisions, want, "§7.2 and §14.4");
}

/// §15.3 and §15.5 give each decision of a key provider its code and label, and each step of
/// an exchange's verification its reasons, as the reference has them.
#[test]
fn the_key_providers_tables_are_the_reference_codes() {
    use wai::key_release::provider::{Fault, Provision};
    let mut decisions: Vec<(String, String)> = rows("### 15.3 The decision and the answer").iter().map(|r| (r[1].clone(), r[2].clone())).collect();
    decisions.sort();
    let mut want: Vec<(String, String)> = Provision::ALL.iter().map(|d| (d.label().to_string(), d.code().to_string())).collect();
    want.sort();
    assert_eq!(decisions, want, "§15.3");
    let mut reasons: Vec<String> = Vec::new();
    for r in rows("### 15.5 Verification") {
        for code in r[1].split(',').map(|c| c.trim().trim_matches('`').to_string()) {
            if !reasons.contains(&code) {
                reasons.push(code);
            }
        }
    }
    assert_eq!(reasons, Fault::ALL.iter().map(|f| f.code().to_string()).collect::<Vec<_>>(), "§15.5");
}