from __future__ import annotations

import importlib.util
from pathlib import Path
import subprocess
import sys


ROOT = Path(__file__).resolve().parents[2]


def load_tile_exporter():
    script_path = ROOT / "scripts" / "export_operator_yolo_tile_dataset.py"
    spec = importlib.util.spec_from_file_location("operator_tile_exporter", script_path)
    assert spec is not None
    assert spec.loader is not None
    module = importlib.util.module_from_spec(spec)
    sys.modules[spec.name] = module
    spec.loader.exec_module(module)
    return module


def test_operator_yolo_tile_dataset_export_script_contract() -> None:
    script_path = ROOT / "scripts" / "export_operator_yolo_tile_dataset.py"
    readiness = (ROOT / "scripts" / "run_readiness_check.sh").read_text(encoding="utf-8")

    assert script_path.exists()
    script = script_path.read_text(encoding="utf-8")

    assert "py_compile scripts/export_operator_yolo_tile_dataset.py" in readiness
    assert "operator_samples_manifest.json" in script
    assert "yolo-building-tile-dataset" in script
    assert "dataset.yaml" in script
    assert "images/train" in script
    assert "labels/train" in script
    assert "images/val" in script
    assert "labels/val" in script
    assert "tile_size" in script
    assert "stride" in script
    assert "negative_keep_ratio" in script
    assert "min_label_visible_ratio" in script
    assert "positive_tile_count" in script
    assert "negative_tile_count" in script
    assert "skipped_negative_tile_count" in script
    assert "source_name" in script
    assert "reference_layer_name" in script
    assert "Window" in script
    assert "Transformer" in script
    assert "fixture_mode" not in script
    assert "will_download_models" not in script


def test_operator_yolo_tile_dataset_export_help_does_not_require_gis_dependencies() -> None:
    script_path = ROOT / "scripts" / "export_operator_yolo_tile_dataset.py"

    result = subprocess.run(
        [sys.executable, str(script_path), "--help"],
        check=False,
        capture_output=True,
        text=True,
    )

    assert result.returncode == 0
    assert "Export operator real-data samples to a tile-level YOLO detection dataset" in result.stdout
    assert "--tile-size" in result.stdout
    assert "--stride" in result.stdout
    assert "--negative-keep-ratio" in result.stdout
    assert "--min-label-visible-ratio" in result.stdout
    assert "--background-negative-repeat" in result.stdout


def test_iter_tile_windows_covers_edges_without_duplicates() -> None:
    module = load_tile_exporter()

    windows = list(module.iter_tile_windows(width=512, height=512, tile_size=192, stride=96))

    assert len(windows) == 25
    assert windows[0].row_off == 0
    assert windows[0].col_off == 0
    assert windows[-1].row_off == 320
    assert windows[-1].col_off == 320
    assert len({(window.row_off, window.col_off) for window in windows}) == len(windows)
    assert all(window.width == 192 for window in windows)
    assert all(window.height == 192 for window in windows)


def test_negative_tile_keep_is_deterministic_and_ratio_bound() -> None:
    module = load_tile_exporter()

    first = [module.keep_negative_tile("geel", index, 0.25) for index in range(50)]
    second = [module.keep_negative_tile("geel", index, 0.25) for index in range(50)]
    all_kept = [module.keep_negative_tile("geel", index, 1.0) for index in range(10)]
    none_kept = [module.keep_negative_tile("geel", index, 0.0) for index in range(10)]

    assert first == second
    assert 1 <= sum(first) <= 25
    assert all(all_kept)
    assert not any(none_kept)


def test_labels_for_tile_can_drop_tiny_visible_box_fragments() -> None:
    module = load_tile_exporter()
    tile = module.TileWindow(row_off=0, col_off=0, height=100, width=100)
    mostly_outside_box = module.PixelBox(min_col=90, min_row=10, max_col=190, max_row=90)

    labels_without_gate = module.labels_for_tile(
        tile,
        [mostly_outside_box],
        min_label_px=4,
        min_visible_ratio=0.0,
    )
    labels_with_gate = module.labels_for_tile(
        tile,
        [mostly_outside_box],
        min_label_px=4,
        min_visible_ratio=0.25,
    )

    assert labels_without_gate == ["0 0.95000000 0.50000000 0.10000000 0.80000000"]
    assert labels_with_gate == []


def test_background_negative_repeat_only_applies_to_training_background_tiles() -> None:
    module = load_tile_exporter()

    assert module.background_negative_repeat_count(
        is_negative=True,
        sample_role="background_candidate",
        split="train",
        background_negative_repeat=4,
    ) == 4
    assert module.background_negative_repeat_count(
        is_negative=True,
        sample_role="background_candidate",
        split="val",
        background_negative_repeat=4,
    ) == 1
    assert module.background_negative_repeat_count(
        is_negative=False,
        sample_role="background_candidate",
        split="train",
        background_negative_repeat=4,
    ) == 1
    assert module.background_negative_repeat_count(
        is_negative=True,
        sample_role="reference",
        split="train",
        background_negative_repeat=4,
    ) == 1