//! `wai audit report|check|verify` and `wai verify` on an audit bundle, against this crate's own program,
//! on the same input: the stream-audit corpus (`live-conformance/audit/`) stored by the collector,
//! a channel's report from that store, the report checked against its bundles, and each bundle
//! verified. Each folded command prints what `wai-audit` prints and exits as it exits, byte for
//! byte; `--owner` is `WAI_AUDIT_OWNER` to the program, and a fold that dropped it would be told
//! apart here (the program refuses to check without an owner).
//!
//! `wai` is built from `wai/wai-rs` with the feature `quickstart`, into a target directory of this
//! test's own.

use ed25519_dalek::SigningKey;
use serde_json::Value;
use sha2::{Digest, Sha256};
use std::path::{Path, PathBuf};
use std::process::{Command, Output, Stdio};
use wai_audit::collector::{Collector, Config};

fn cargo() -> String {
    std::env::var("CARGO").unwrap_or_else(|_| "cargo".into())
}

fn exe(name: &str) -> String {
    format!("{name}{}", std::env::consts::EXE_SUFFIX)
}

/// The `wai` binary, built with the feature quickstart.
fn wai_bin() -> PathBuf {
    let manifest = Path::new(env!("CARGO_MANIFEST_DIR")).join("../wai-rs/Cargo.toml");
    let target = Path::new(env!("CARGO_TARGET_TMPDIR")).join("wai-quickstart");
    let status = Command::new(cargo())
        .args(["build", "--locked", "--no-default-features", "--features", "quickstart", "--bin", "wai", "--manifest-path"])
        .arg(&manifest)
        .env("CARGO_TARGET_DIR", &target)
        .status()
        .expect("cargo runs");
    assert!(status.success(), "the wai binary builds with the feature quickstart");
    target.join("debug").join(exe("wai"))
}

fn corpus() -> Value {
    let p = Path::new(env!("CARGO_MANIFEST_DIR")).join("../live-conformance/audit/vectors.json");
    serde_json::from_slice(&std::fs::read(&p).unwrap()).unwrap()
}

/// The corpus's owner key: SHA-256 of its label and index 0 (its README).
fn owner_seed() -> [u8; 32] {
    let mut h = Sha256::new();
    h.update(b"wai:stream-audit/corpus/key\x00");
    h.update([0u8]);
    h.finalize().into()
}

fn bundle_bytes(v: &Value) -> Vec<u8> {
    match &v["bundle_text"] {
        Value::String(s) => s.clone().into_bytes(),
        _ => serde_json::to_vec(&v["bundle"]).unwrap(),
    }
}

fn run(bin: &Path, args: &[&str], envs: &[(&str, &str)]) -> Output {
    let mut c = Command::new(bin);
    c.args(args).env_remove("WAI_AUDIT_OWNER").env_remove("WAI_AUDIT_KEY").stdin(Stdio::null());
    for (k, v) in envs {
        c.env(k, v);
    }
    c.output().expect("it runs")
}

fn text(o: &Output) -> String {
    format!("{}{}", String::from_utf8_lossy(&o.stdout), String::from_utf8_lossy(&o.stderr))
}

fn same(a: &Output, b: &Output, what: &str) {
    assert_eq!(a.status.code(), b.status.code(), "{what}: the exit status\n{}\n---\n{}", text(a), text(b));
    assert_eq!(String::from_utf8_lossy(&a.stdout), String::from_utf8_lossy(&b.stdout), "{what}: standard output");
    assert_eq!(String::from_utf8_lossy(&a.stderr), String::from_utf8_lossy(&b.stderr), "{what}: standard error");
}

#[test]
fn the_folds_print_what_wai_audit_prints() {
    let wai = wai_bin();
    let me = Path::new(env!("CARGO_BIN_EXE_wai-audit"));
    let m = me.to_str().unwrap();
    let doc = corpus();
    let dir = Path::new(env!("CARGO_TARGET_TMPDIR")).join("fold");
    let _ = std::fs::remove_dir_all(&dir);
    std::fs::create_dir_all(&dir).unwrap();
    // The collector's store, every session of the corpus posted to it, and its key's file.
    let channels: Vec<String> = doc["channels"].as_array().unwrap().iter().map(|c| c.as_str().unwrap().to_string()).collect();
    let data = dir.join("data");
    let config = Config { channels: channels.clone(), data: data.clone(), allow_origins: vec![], max_bundle: 4 << 20, max_batch: 64 << 10, per_minute: u32::MAX };
    let collector = Collector::new(config, SigningKey::from_bytes(&owner_seed()));
    for s in doc["sessions"].as_array().unwrap() {
        collector.submit(&bundle_bytes(s));
    }
    let key = dir.join("owner.key");
    std::fs::write(&key, owner_seed()).unwrap();
    let k = key.to_str().unwrap();
    let owner = doc["owner"].as_str().unwrap();

    for r in doc["reports"].as_array().unwrap().iter().filter(|r| r["outcome"]["outcome"] == "accept") {
        let name = r["name"].as_str().unwrap();
        let chan = r["channel"].as_str().unwrap();
        let rep = &r["served"]["report"];
        let (from, to) = (rep["from"].to_string(), rep["to"].to_string());
        // The report: wai-audit's, byte for byte, and the corpus's.
        let theirs = run(me, &["report", data.to_str().unwrap(), chan, &from, &to], &[("WAI_AUDIT_KEY", k)]);
        let ours = run(&wai, &["audit", "report", data.to_str().unwrap(), chan, &from, &to, "--audit", m], &[("WAI_AUDIT_KEY", k)]);
        same(&ours, &theirs, &format!("{name}: report"));
        if !theirs.status.success() {
            continue;
        }
        let served: Value = serde_json::from_slice(&theirs.stdout).unwrap();
        assert_eq!(served, r["served"], "{name}: the report is the corpus's");
        let served_file = dir.join(format!("{name}.served.json"));
        std::fs::write(&served_file, &theirs.stdout).unwrap();
        // With --json, the envelope carries its JSON.
        let j = run(&wai, &["audit", "report", data.to_str().unwrap(), chan, &from, &to, "--audit", m, "--json"], &[("WAI_AUDIT_KEY", k)]);
        let e: Value = serde_json::from_slice(&j.stdout).unwrap_or_else(|e| panic!("{e}: {}", text(&j)));
        assert_eq!(e["data"], served, "{name}: --json");

        // The report checked against the bundles it reads.
        let bundles: Vec<PathBuf> = r["sessions"]
            .as_array()
            .unwrap()
            .iter()
            .map(|n| {
                let s = doc["sessions"].as_array().unwrap().iter().find(|s| s["name"] == *n).unwrap();
                let f = dir.join(format!("{}.bundle.json", n.as_str().unwrap()));
                std::fs::write(&f, bundle_bytes(s)).unwrap();
                f
            })
            .collect();
        let mut check = vec!["check", served_file.to_str().unwrap(), chan];
        check.extend(bundles.iter().map(|b| b.to_str().unwrap()));
        let theirs = run(me, &check, &[("WAI_AUDIT_OWNER", owner)]);
        let mut fold = vec!["audit"];
        fold.extend(&check);
        fold.extend(["--owner", owner, "--audit", m]);
        let ours = run(&wai, &fold, &[]);
        same(&ours, &theirs, &format!("{name}: check"));
        assert!(theirs.status.success(), "{name}: {}", text(&theirs));
        // Without the owner the program refuses: a fold that dropped --owner is told apart.
        let ownerless = run(me, &check, &[]);
        assert_ne!(ownerless.status.code(), ours.status.code(), "{name}: the owner matters to the check");
        // A bundle left out: refused by both alike.
        if bundles.len() > 1 {
            let short: Vec<&str> = check[..check.len() - 1].to_vec();
            let theirs = run(me, &short, &[("WAI_AUDIT_OWNER", owner)]);
            let mut f = vec!["audit"];
            f.extend(&short);
            f.extend(["--owner", owner, "--audit", m]);
            let ours = run(&wai, &f, &[]);
            assert_eq!(theirs.status.code(), Some(1), "{name}: {}", text(&theirs));
            same(&ours, &theirs, &format!("{name}: a bundle left out"));
        }
    }

    // Each bundle verified: `wai audit verify` is wai-audit verify, byte for byte, and wai verify's
    // answer for the bundle is the same JSON.
    let mut flags = Vec::new();
    for c in &channels {
        flags.extend(["--channel", c.as_str()]);
    }
    let mut n = 0;
    for s in doc["sessions"].as_array().unwrap().iter().filter(|s| s["bundle"].is_object()) {
        let name = s["name"].as_str().unwrap();
        let f = dir.join(format!("verify-{name}.json"));
        std::fs::write(&f, bundle_bytes(s)).unwrap();
        let file = f.to_str().unwrap();
        let mut a = vec!["verify", file];
        a.extend(channels.iter().map(String::as_str));
        let theirs = run(me, &a, &[("WAI_AUDIT_OWNER", owner)]);
        let mut folded = vec!["audit"];
        folded.extend(&a);
        folded.extend(["--owner", owner, "--audit", m]);
        same(&run(&wai, &folded, &[]), &theirs, &format!("{name}: audit verify"));
        let mut v = vec!["verify", file, "--owner", owner];
        v.extend(&flags);
        let ours = run(&wai, &v, &[]);
        assert_eq!(ours.status.code(), theirs.status.code(), "{name}: {}\n{}", text(&ours), text(&theirs));
        let body: String = String::from_utf8_lossy(&ours.stdout).lines().skip(1).take_while(|l| !l.starts_with("wai verify:")).map(|l| l.strip_prefix("  ").unwrap_or(l)).collect::<Vec<_>>().join("\n");
        assert_eq!(format!("{body}\n"), String::from_utf8_lossy(&theirs.stdout), "{name}: wai-audit verify's JSON");
        n += 1;
    }
    assert!(n > 80, "{n} bundles");
}