"""Tests for capture region-of-interest (ROI) cropping."""

import numpy as np

from ledgrab.core.capture.calibration import (
    CalibrationConfig,
    calibration_from_dict,
    calibration_to_dict,
)
from ledgrab.core.capture.screen_capture import ScreenCapture, crop_screen_capture


def _cfg(**kw) -> CalibrationConfig:
    return CalibrationConfig(layout="clockwise", start_position="bottom_left", leds_top=10, **kw)


def _sc(w: int = 100, h: int = 80) -> ScreenCapture:
    return ScreenCapture(
        image=np.zeros((h, w, 3), dtype=np.uint8), width=w, height=h, display_index=0
    )


def test_full_frame_returns_same_object():
    sc = _sc()
    assert crop_screen_capture(sc, 0.0, 0.0, 1.0, 1.0) is sc


def test_center_crop_dimensions():
    out = crop_screen_capture(_sc(100, 80), 0.25, 0.25, 0.5, 0.5)
    assert out.width == 50 and out.height == 40
    assert out.image.shape[:2] == (40, 50)
    assert out.display_index == 0


def test_crop_returns_a_view_of_the_source():
    sc = _sc(100, 80)
    out = crop_screen_capture(sc, 0.0, 0.0, 0.5, 0.5)
    out.image[0, 0] = (9, 9, 9)
    assert (sc.image[0, 0] == 9).all()  # mutating the view touches the source pixels


def test_partial_width_only_keeps_full_height():
    out = crop_screen_capture(_sc(100, 80), 0.1, 0.0, 0.8, 1.0)
    assert out.width == 80 and out.height == 80


def test_degenerate_roi_clamped_to_at_least_one_pixel():
    out = crop_screen_capture(_sc(100, 80), 0.999, 0.999, 0.0, 0.0)
    assert out.width >= 1 and out.height >= 1


def test_out_of_range_roi_is_clamped():
    out = crop_screen_capture(_sc(100, 80), -0.5, -0.5, 2.0, 2.0)
    # x<=0,y<=0,w>=1,h>=1 hits the full-frame fast path
    assert out.width == 100 and out.height == 80


# --- CalibrationConfig ROI serialization ---


def test_has_roi_property():
    assert _cfg().has_roi is False
    assert _cfg(roi_width=0.5).has_roi is True
    assert _cfg(roi_x=0.1).has_roi is True
    assert _cfg(roi_height=0.9).has_roi is True


def test_roi_round_trips_through_dict():
    cfg = _cfg(roi_x=0.1, roi_y=0.2, roi_width=0.6, roi_height=0.7)
    d = calibration_to_dict(cfg)
    assert d["roi_x"] == 0.1 and d["roi_width"] == 0.6
    back = calibration_from_dict(d)
    assert (back.roi_x, back.roi_y, back.roi_width, back.roi_height) == (0.1, 0.2, 0.6, 0.7)


def test_full_frame_roi_omitted_from_dict():
    d = calibration_to_dict(_cfg())
    assert "roi_x" not in d and "roi_width" not in d


def test_legacy_dict_without_roi_defaults_to_full_frame():
    cfg = calibration_from_dict(
        {"mode": "simple", "layout": "clockwise", "start_position": "bottom_left", "leds_top": 10}
    )
    assert cfg.has_roi is False
    assert (cfg.roi_x, cfg.roi_y, cfg.roi_width, cfg.roi_height) == (0.0, 0.0, 1.0, 1.0)