//! Replay the published `energy_trace/1` pack from disk.
//!
//! SPEC §5.3–5.6 states rules, and `gen_trace_vectors` emits the vectors. This
//! reads those bytes back — the same bytes a third party would — and checks the
//! reference implementation reproduces every recorded verdict. A pack only its
//! own generator can read is not a conformance pack.
//!
//! The refusals matter more than the acceptances. An implementation that admits
//! an unbound outcome, a double-counted activity or a frozen counter has failed
//! in the direction that flatters, which is the direction nobody notices.

use jcp_efficiency::dynamics::{
    DrawShape, EnergyWindow, PhysicalVerdict, PowerEnvelope,
};
use jcp_efficiency::trace::{OutcomeTrace, TraceError};
use serde_json::Value;

fn pack() -> Value {
    let p = std::path::Path::new(env!("CARGO_MANIFEST_DIR"))
        .join("../../../conformance/v1/energy_trace.json");
    // Assert, not skip. A `return` here would make this test pass green in the
    // one case it exists to catch — the pack going missing or moving.
    assert!(
        p.exists(),
        "conformance pack missing at {} — it is what this test replays",
        p.display()
    );
    let bytes = std::fs::read(&p).unwrap_or_else(|e| panic!("read {}: {e}", p.display()));
    serde_json::from_slice(&bytes).expect("pack parses")
}

#[test]
fn the_pack_declares_its_profile_and_spec() {
    let v = pack();
    assert_eq!(v["profile"], "energy_trace/1");
    assert!(v["spec"].as_str().unwrap().contains("5.3-5.6"));
}

/// Every positive conservation vector reproduces its recorded reconciliation.
#[test]
fn conservation_positives_reproduce_their_recorded_verdicts() {
    let v = pack();
    let cases = v["conservation"]["positive"].as_array().expect("positives");
    assert!(cases.len() >= 2, "expected the published positive cases");
    for c in cases {
        let note = c["note"].as_str().unwrap_or("?");
        let t: OutcomeTrace =
            serde_json::from_value(c["input"].clone()).unwrap_or_else(|e| panic!("{note}: {e}"));
        let r = t.reconcile().unwrap_or_else(|e| panic!("{note}: must reconcile: {e}"));
        let exp = &c["expected"];
        assert_eq!(
            serde_json::to_value(r.accounted_uj).unwrap(), exp["accounted_uj"],
            "{note}: accounted"
        );
        assert_eq!(
            serde_json::to_value(r.residual_uj).unwrap(), exp["residual_uj"],
            "{note}: the residual is the whole point"
        );
        assert_eq!(
            serde_json::to_value(r.provenance_floor).unwrap(), exp["provenance_floor"],
            "{note}: provenance takes the floor"
        );
        assert_eq!(
            serde_json::to_value(r.coverage_floor).unwrap(), exp["coverage_floor"],
            "{note}: coverage takes the floor"
        );
    }
}

/// Every refusal is actually refused, and for the recorded reason. An
/// implementation that accepted these would be wrong in the flattering
/// direction.
#[test]
fn conservation_negatives_are_refused_for_the_recorded_reason() {
    let v = pack();
    let cases = v["conservation"]["negative"].as_array().expect("negatives");
    assert!(cases.len() >= 3, "expected the three published refusals");
    for c in cases {
        let note = c["note"].as_str().unwrap_or("?");
        let t: OutcomeTrace =
            serde_json::from_value(c["input"].clone()).unwrap_or_else(|e| panic!("{note}: {e}"));
        let err = t.reconcile().expect_err(&format!("{note}: must be refused"));
        let want = c["expected"]["error"].as_str().unwrap();
        let got = match err {
            TraceError::Unbound => "Unbound",
            TraceError::DuplicateActivity { .. } => "DuplicateActivity",
            TraceError::OverAccounted { .. } => "OverAccounted",
        };
        assert_eq!(got, want, "{note}: refused, but for the wrong reason");
    }
}

/// The physical bound refutes above the envelope and below the floor — the
/// second being the shape a frozen counter takes.
#[test]
fn physical_bounds_reproduce_their_recorded_verdicts() {
    let v = pack();
    let env: PowerEnvelope =
        serde_json::from_value(v["physical"]["envelope"].clone()).expect("envelope");
    let cases = v["physical"]["cases"].as_array().expect("cases");
    assert!(cases.len() >= 4);
    let mut saw_below = false;
    for c in cases {
        let note = c["note"].as_str().unwrap_or("?");
        let w: EnergyWindow =
            serde_json::from_value(c["input"].clone()).unwrap_or_else(|e| panic!("{note}: {e}"));
        let got = match env.check(&w) {
            PhysicalVerdict::NotRefuted { .. } => "NotRefuted",
            PhysicalVerdict::RefutedAbove { .. } => "RefutedAbove",
            PhysicalVerdict::RefutedBelow { claimed_uj, floor_uj } => {
                saw_below = true;
                if let Some(f) = c["expected"]["floor_uj"].as_u64() {
                    assert_eq!(floor_uj, f, "{note}: floor");
                    assert_eq!(claimed_uj, 0, "{note}: a frozen counter claims nothing");
                }
                "RefutedBelow"
            }
            PhysicalVerdict::Unboundable => "Unboundable",
        };
        assert_eq!(got, c["expected"]["verdict"].as_str().unwrap(), "{note}");
    }
    assert!(saw_below, "the frozen-counter refutation must be in the pack");
}

/// Character survives a change of scale, and a padded total does not read as
/// sustained. These two together are what the shape check is for.
#[test]
fn draw_character_reproduces_its_recorded_verdicts() {
    let v = pack();
    let floor = v["shape"]["idle_floor_uj"].as_u64().expect("idle floor");
    let cases = v["shape"]["cases"].as_array().expect("cases");
    assert!(cases.len() >= 6);
    let mut saw_inconsistent = false;
    for c in cases {
        let note = c["note"].as_str().unwrap_or("?");
        let declared: DrawShape =
            serde_json::from_value(c["input"]["declared"].clone()).expect("declared");
        let windows: Vec<EnergyWindow> =
            serde_json::from_value(c["input"]["windows"].clone()).expect("windows");
        let got = jcp_efficiency::dynamics::check_shape(declared, &windows, floor);
        let want = c["expected"]["verdict"].as_str().unwrap();
        let name = match &got {
            jcp_efficiency::dynamics::ShapeVerdict::Consistent { shape } => {
                if let Some(s) = c["expected"]["shape"].as_str() {
                    assert_eq!(
                        serde_json::to_value(shape).unwrap().as_str().unwrap(), s,
                        "{note}: shape"
                    );
                }
                "Consistent"
            }
            jcp_efficiency::dynamics::ShapeVerdict::Inconsistent { .. } => {
                saw_inconsistent = true;
                "Inconsistent"
            }
            jcp_efficiency::dynamics::ShapeVerdict::Unresolvable { windows } => {
                if let Some(n) = c["expected"]["windows"].as_u64() {
                    assert_eq!(*windows as u64, n, "{note}: window count");
                }
                "Unresolvable"
            }
        };
        assert_eq!(name, want, "{note}");
    }
    assert!(saw_inconsistent, "the padding refutation must be in the pack");
}

/// Anti-vacuity across the whole pack: a wrong path, a renamed key or an empty
/// array would otherwise let every test above pass having checked nothing.
#[test]
fn the_pack_carries_every_section_it_claims() {
    let v = pack();
    for section in ["conservation", "budget", "physical", "shape", "dynamism"] {
        assert!(!v[section].is_null(), "section {section} missing from the pack");
    }
    let total: usize = v["conservation"]["positive"].as_array().map_or(0, Vec::len)
        + v["conservation"]["negative"].as_array().map_or(0, Vec::len)
        + v["physical"]["cases"].as_array().map_or(0, Vec::len)
        + v["shape"]["cases"].as_array().map_or(0, Vec::len)
        + v["dynamism"]["cases"].as_array().map_or(0, Vec::len)
        + v["budget"]["positive"].as_array().map_or(0, Vec::len)
        + v["budget"]["negative"].as_array().map_or(0, Vec::len);
    assert!(total >= 20, "expected the full published pack, replayed {total} cases");
}