import json

import numpy as np

from src.load_t2_material_loading_memory import load_trajectory
from src.t2_material_loading_memory import prescribed_history
from src.t2_material_loading_memory_v1 import (
    DATA_DIR,
    MATERIAL_MODELS,
    PATH_FAMILIES,
    case_identity,
    design_parameters,
    split_assignments,
)


def test_v1_design_is_unique_balanced_and_stratified():
    rows = design_parameters()
    split = split_assignments(rows)
    assert len(rows) == 1008
    assert len({case_identity(row) for row in rows}) == 1008
    assert sum(value == "train" for value in split.values()) == 768
    assert sum(value == "validation" for value in split.values()) == 120
    assert sum(value == "test" for value in split.values()) == 120
    for model in MATERIAL_MODELS:
        assert sum(row["material_model"] == model for row in rows) == 504
        for family in PATH_FAMILIES:
            indices = [
                index
                for index, row in enumerate(rows)
                if row["material_model"] == model and row["path_family"] == family
            ]
            assert len(indices) == 84
            assert sum(split[index] == "train" for index in indices) == 64
            assert sum(split[index] == "validation" for index in indices) == 10
            assert sum(split[index] == "test" for index in indices) == 10


def test_v1_parameter_ranges_and_model_labels_are_explicit():
    rows = design_parameters()
    for row in rows:
        assert 150.0e9 <= row["young_pa"] <= 230.0e9
        assert 0.25 <= row["poisson"] <= 0.34
        assert 180.0e6 <= row["yield_stress_pa"] <= 450.0e6
        assert 0.003 <= row["maximum_equivalent_strain"] <= 0.012
        if row["material_model"] == "j2_linear_isotropic":
            assert row["backstress_c1_pa"] == 0.0
            assert row["isotropic_saturation_pa"] == 0.0
        else:
            assert row["hardening_modulus_pa"] == 0.0
            assert row["backstress_c1_pa"] > 0.0


def test_v1_histories_preserve_reversals_under_refinement():
    for row in design_parameters()[::83]:
        _, coarse, anchors = prescribed_history(row, points=121)
        _, fine, _ = prescribed_history(row, points=241)
        np.testing.assert_allclose(coarse, fine[::2], rtol=0.0, atol=1.0e-15)
        for anchor in anchors:
            assert np.any(np.isclose(coarse, anchor, rtol=0.0, atol=1.0e-15))


def test_v1_packaged_data_and_lightweight_reader_when_present():
    manifest_path = DATA_DIR / "manifest.json"
    if not manifest_path.exists():
        return
    manifest = json.loads(manifest_path.read_text(encoding="utf-8"))
    assert manifest["sample_count"] == 1008
    assert len(manifest["shards"]) == 8
    sample = load_trajectory(DATA_DIR, 0)
    assert sample["history"]["stress_pa"].shape == (121, 3, 3)
    assert np.isfinite(sample["history"]["stress_pa"]).all()