"""Tests for solver.models.graph_conv -- assembly to PyG conversion."""

from __future__ import annotations

import torch

from solver.datagen.generator import SyntheticAssemblyGenerator
from solver.datagen.types import JointType
from solver.models.graph_conv import ASSEMBLY_CLASSES, JOINT_TYPE_NAMES, assembly_to_pyg


def _make_example(n_bodies: int = 4, grounded: bool = True, seed: int = 0) -> dict:
    """Generate a single training example via the datagen pipeline."""
    gen = SyntheticAssemblyGenerator(seed=seed)
    batch = gen.generate_training_batch(batch_size=1, n_bodies_range=(n_bodies, n_bodies + 1))
    return batch[0]


class TestAssemblyToPyg:
    """assembly_to_pyg converts datagen dicts to PyG Data correctly."""

    def test_node_feature_shape(self) -> None:
        ex = _make_example(n_bodies=5)
        data = assembly_to_pyg(ex)
        assert data.x.shape == (5, 22)

    def test_edge_feature_shape(self) -> None:
        ex = _make_example(n_bodies=4)
        data = assembly_to_pyg(ex)
        n_joints = ex["n_joints"]
        assert data.edge_attr.shape == (n_joints * 2, 22)

    def test_edge_index_bidirectional(self) -> None:
        ex = _make_example(n_bodies=4)
        data = assembly_to_pyg(ex)
        ei = data.edge_index
        # Each joint produces 2 directed edges: a->b and b->a.
        for i in range(0, ei.size(1), 2):
            assert ei[0, i].item() == ei[1, i + 1].item()
            assert ei[1, i].item() == ei[0, i + 1].item()

    def test_edge_index_shape(self) -> None:
        ex = _make_example(n_bodies=4)
        data = assembly_to_pyg(ex)
        n_joints = ex["n_joints"]
        assert data.edge_index.shape == (2, n_joints * 2)

    def test_node_features_centered(self) -> None:
        ex = _make_example(n_bodies=5)
        data = assembly_to_pyg(ex)
        # Positions (dims 0-2) should be centered (mean ~0).
        pos = data.x[:, :3]
        assert pos.mean(dim=0).abs().max().item() < 1e-5

    def test_grounded_flag_set(self) -> None:
        ex = _make_example(n_bodies=4, grounded=True)
        ex["grounded"] = True
        data = assembly_to_pyg(ex)
        assert data.x[0, 12].item() == 1.0

    def test_ungrounded_flag_clear(self) -> None:
        ex = _make_example(n_bodies=4)
        ex["grounded"] = False
        data = assembly_to_pyg(ex)
        assert (data.x[:, 12] == 0.0).all()

    def test_edge_type_one_hot_valid(self) -> None:
        ex = _make_example(n_bodies=5)
        data = assembly_to_pyg(ex)
        if data.edge_attr.size(0) > 0:
            onehot = data.edge_attr[:, :11]
            # Each row should have exactly one 1.0.
            assert (onehot.sum(dim=1) == 1.0).all()

    def test_labels_present_when_requested(self) -> None:
        ex = _make_example(n_bodies=4)
        data = assembly_to_pyg(ex, include_labels=True)
        assert hasattr(data, "y_edge")
        assert hasattr(data, "y_graph")
        assert hasattr(data, "y_joint_type")
        assert hasattr(data, "y_dof")
        assert hasattr(data, "y_body_dof")

    def test_labels_absent_when_not_requested(self) -> None:
        ex = _make_example(n_bodies=4)
        data = assembly_to_pyg(ex, include_labels=False)
        assert not hasattr(data, "y_edge")
        assert not hasattr(data, "y_graph")

    def test_graph_classification_label_mapping(self) -> None:
        ex = _make_example(n_bodies=4)
        data = assembly_to_pyg(ex)
        cls = ex["assembly_classification"]
        expected = ASSEMBLY_CLASSES[cls]
        assert data.y_graph.item() == expected

    def test_body_dof_shape(self) -> None:
        ex = _make_example(n_bodies=5)
        data = assembly_to_pyg(ex)
        assert data.y_body_dof.shape == (5, 2)

    def test_edge_labels_binary(self) -> None:
        ex = _make_example(n_bodies=5)
        data = assembly_to_pyg(ex)
        if data.y_edge.numel() > 0:
            assert ((data.y_edge == 0.0) | (data.y_edge == 1.0)).all()

    def test_dof_removed_normalized(self) -> None:
        ex = _make_example(n_bodies=4)
        data = assembly_to_pyg(ex)
        if data.edge_attr.size(0) > 0:
            dof_norm = data.edge_attr[:, 21]
            assert (dof_norm >= 0.0).all()
            assert (dof_norm <= 1.0).all()

    def test_roundtrip_with_generator(self) -> None:
        """Generate a real example and convert -- no crash."""
        gen = SyntheticAssemblyGenerator(seed=42)
        batch = gen.generate_training_batch(batch_size=5, complexity_tier="simple")
        for ex in batch:
            data = assembly_to_pyg(ex)
            assert data.x.shape[1] == 22
            assert data.edge_attr.shape[1] == 22


class TestAssemblyClasses:
    """ASSEMBLY_CLASSES covers all classifications."""

    def test_four_classes(self) -> None:
        assert len(ASSEMBLY_CLASSES) == 4

    def test_values_are_0_to_3(self) -> None:
        assert set(ASSEMBLY_CLASSES.values()) == {0, 1, 2, 3}


class TestJointTypeNames:
    """JOINT_TYPE_NAMES matches the JointType enum."""

    def test_length_matches_enum(self) -> None:
        assert len(JOINT_TYPE_NAMES) == len(JointType)

    def test_order_matches_ordinal(self) -> None:
        for i, name in enumerate(JOINT_TYPE_NAMES):
            assert JointType[name].value[0] == i