//! C28 structural fitness: the node crates obey the ladder import direction.
//! The compiler only rejects import cycles; an acyclic-but-outward dependency
//! (e.g. `aura-std` -> `aura-market`) would compile silently. This test reads
//! each node crate's `[dependencies]` table and asserts its intra-workspace edges
//! stay within the inner set C28 permits for that layer. `[dev-dependencies]` are
//! C28-exempt (tests may cross layers) and are deliberately not inspected.

use std::path::PathBuf;

fn workspace_root() -> PathBuf {
    // aura-vocabulary/ + /../.. = workspace root (the repo idiom for reaching it).
    PathBuf::from(env!("CARGO_MANIFEST_DIR")).join("..").join("..")
}

/// The `aura-*` keys under `[dependencies]` (NOT `[dev-dependencies]`) of a crate.
fn prod_intra_workspace_deps(crate_name: &str) -> Vec<String> {
    let manifest = workspace_root()
        .join("crates")
        .join(crate_name)
        .join("Cargo.toml");
    let text = std::fs::read_to_string(&manifest)
        .unwrap_or_else(|e| panic!("read {}: {e}", manifest.display()));
    let doc: toml::Value = toml::from_str(&text).expect("Cargo.toml parses as TOML");
    match doc.get("dependencies").and_then(|d| d.as_table()) {
        Some(deps) => deps
            .keys()
            .filter(|k| k.starts_with("aura-"))
            .cloned()
            .collect(),
        None => Vec::new(),
    }
}

#[test]
fn node_crates_obey_the_c28_import_direction() {
    // (crate, the intra-workspace [dependencies] C28 permits for its layer)
    let allowed: &[(&str, &[&str])] = &[
        ("aura-analysis", &[]),                          // foundation: no aura-* deps
        ("aura-measurement", &["aura-core", "aura-analysis"]),
        ("aura-std", &["aura-core"]),
        ("aura-market", &["aura-core"]),
        ("aura-strategy", &["aura-core"]),
        ("aura-engine", &["aura-core", "aura-analysis"]),
        ("aura-backtest", &["aura-core", "aura-engine"]),
        (
            "aura-vocabulary",
            &["aura-core", "aura-std", "aura-market", "aura-strategy", "aura-backtest"],
        ),
    ];
    for (crate_name, permitted) in allowed {
        for dep in prod_intra_workspace_deps(crate_name) {
            assert!(
                permitted.contains(&dep.as_str()),
                "C28 import-direction violation: `{crate_name}` [dependencies] on `{dep}`, \
                 outside its permitted inner set {permitted:?}"
            );
        }
    }
}