"""Unit tests for cores.correlation — matchers + graph builder."""

from __future__ import annotations

import numpy as np

from cores.correlation import (
    CorrelationGraphBuilder, Node, EdgeType,
    match_faces, match_objects, match_locations, match_cameras,
    match_hashes, match_embeddings, match_metadata, match_timestamps,
)


class TestMatchFaces:
    def test_identical_embeddings_match(self):
        emb = np.random.randn(128).astype(np.float32)
        matches = match_faces([("f1", emb), ("f2", emb)], threshold=0.9)
        assert len(matches) == 1
        assert matches[0][0] == "f1"
        assert matches[0][1] == "f2"
        assert matches[0][2] >= 0.9

    def test_different_embeddings_no_match(self):
        emb1 = np.random.randn(128).astype(np.float32)
        emb2 = -emb1
        matches = match_faces([("f1", emb1), ("f2", emb2)], threshold=0.9)
        assert len(matches) == 0

    def test_empty_list(self):
        assert match_faces([]) == []


class TestMatchObjects:
    def test_same_class_overlapping(self):
        objects = [
            ("o1", "car", {"x": 0, "y": 0, "w": 100, "h": 100}),
            ("o2", "car", {"x": 10, "y": 10, "w": 100, "h": 100}),
        ]
        matches = match_objects(objects, iou_threshold=0.5)
        assert len(matches) == 1

    def test_different_class_no_match(self):
        objects = [
            ("o1", "car", {"x": 0, "y": 0, "w": 100, "h": 100}),
            ("o2", "truck", {"x": 10, "y": 10, "w": 100, "h": 100}),
        ]
        matches = match_objects(objects, iou_threshold=0.5)
        assert len(matches) == 0

    def test_non_overlapping_no_match(self):
        objects = [
            ("o1", "car", {"x": 0, "y": 0, "w": 50, "h": 50}),
            ("o2", "car", {"x": 200, "y": 200, "w": 50, "h": 50}),
        ]
        matches = match_objects(objects, iou_threshold=0.5)
        assert len(matches) == 0


class TestMatchLocations:
    def test_nearby_coordinates_match(self):
        locs = [
            ("l1", {"lat": 48.85, "lon": 2.35}),
            ("l2", {"lat": 48.8501, "lon": 2.3501}),
        ]
        matches = match_locations(locs, distance_threshold=0.01)
        assert len(matches) == 1

    def test_far_coordinates_no_match(self):
        locs = [
            ("l1", {"lat": 48.85, "lon": 2.35}),
            ("l2", {"lat": 40.71, "lon": -74.01}),
        ]
        matches = match_locations(locs, distance_threshold=0.01)
        assert len(matches) == 0


class TestMatchCameras:
    def test_fingerprint_match(self):
        cameras = [
            ("c1", "Canon", "EOS 5D", "abc123fingerprint"),
            ("c2", "Canon", "EOS 5D", "abc123fingerprint"),
        ]
        matches = match_cameras(cameras)
        assert len(matches) == 1
        assert matches[0][2] >= 0.9

    def test_make_model_match(self):
        cameras = [
            ("c1", "Nikon", "D850", "fp1"),
            ("c2", "Nikon", "D850", "fp2"),
        ]
        matches = match_cameras(cameras)
        assert len(matches) == 1
        assert 0.5 < matches[0][2] < 0.9

    def test_different_cameras_no_match(self):
        cameras = [
            ("c1", "Canon", "EOS", "fp1"),
            ("c2", "Nikon", "D850", "fp2"),
        ]
        matches = match_cameras(cameras)
        assert len(matches) == 0


class TestMatchHashes:
    def test_sha256_exact_match(self):
        hashes = [
            ("h1", "abc123def456", "phash1"),
            ("h2", "abc123def456", "phash2"),
        ]
        matches = match_hashes(hashes)
        assert len(matches) == 1
        assert matches[0][2] == 1.0

    def test_phash_near_match(self):
        # Two pHashes that differ by 2 bits
        phash1 = "ffff"  # all 1s
        phash2 = "fffd"  # differs by 1 hex digit = up to 4 bits
        hashes = [
            ("h1", "sha1", phash1),
            ("h2", "sha2", phash2),
        ]
        matches = match_hashes(hashes)
        assert len(matches) == 1


class TestMatchTimestamps:
    def test_close_timestamps_match(self):
        timestamps = [
            ("t1", "2023-01-15T14:30:45Z"),
            ("t2", "2023-01-15T14:31:00Z"),  # 15 seconds apart
        ]
        matches = match_timestamps(timestamps, tolerance_seconds=60)
        assert len(matches) == 1

    def test_far_timestamps_no_match(self):
        timestamps = [
            ("t1", "2023-01-15T14:30:45Z"),
            ("t2", "2023-06-15T14:30:45Z"),  # months apart
        ]
        matches = match_timestamps(timestamps, tolerance_seconds=60)
        assert len(matches) == 0


class TestGraphBuilder:
    def test_build_empty(self):
        builder = CorrelationGraphBuilder()
        graph = builder.build()
        assert graph.num_nodes == 0
        assert graph.num_edges == 0

    def test_build_with_nodes_and_edges(self):
        builder = CorrelationGraphBuilder()
        builder.add_node(Node(id="f1", node_type="face", label="Face 1"))
        builder.add_node(Node(id="f2", node_type="face", label="Face 2"))
        builder.add_matches(EdgeType.SAME_FACE, [
            ("f1", "f2", 0.95, "cosine=0.95"),
        ])
        graph = builder.build()
        assert graph.num_nodes == 2
        assert graph.num_edges == 1
        assert graph.edges[0].edge_type == "same_face"
        assert graph.edges[0].confidence == 0.95

    def test_deduplicates_nodes(self):
        builder = CorrelationGraphBuilder()
        builder.add_node(Node(id="f1", node_type="face"))
        builder.add_node(Node(id="f1", node_type="face"))  # dup
        graph = builder.build()
        assert graph.num_nodes == 1

    def test_deduplicates_edges(self):
        builder = CorrelationGraphBuilder()
        builder.add_matches(EdgeType.SAME_FACE, [
            ("f1", "f2", 0.9, "a"),
            ("f2", "f1", 0.9, "b"),  # reverse dup
        ])
        graph = builder.build()
        assert graph.num_edges == 1