import numpy as np
from backend.data_types import DataField, LineData


def test_line_cursors():
    from backend.nodes.cursors import Cursors

    node = Cursors()
    line_spec = Cursors.INPUT_TYPES()["required"]["line"]
    assert line_spec[0] == "LINE"
    assert line_spec[1]["accepted_types"] == ["DATA_FIELD"]

    line = np.linspace(0, 10, 100).astype(np.float64)

    overlays = []
    Cursors._broadcast_overlay_fn = lambda nid, data: overlays.append(data)
    Cursors._current_node_id = "test"

    table, coord_pair = node.process(line, x1=0.25, y1=0.5, x2=0.75, y2=0.5)
    assert isinstance(coord_pair, tuple) and len(coord_pair) == 2
    assert len(table) == 6
    quantities = {row["quantity"] for row in table}
    assert "A x" in quantities
    assert "B x" in quantities
    assert "dx" in quantities
    assert "dy" in quantities

    a_pos = next(r["value"] for r in table if r["quantity"] == "A x")
    b_pos = next(r["value"] for r in table if r["quantity"] == "B x")
    assert b_pos > a_pos

    dy = next(r["value"] for r in table if r["quantity"] == "dy")
    assert dy > 0

    assert len(overlays) == 1
    assert overlays[0]["kind"] == "line_plot"
    assert len(overlays[0]["line"]) == len(line)
    assert len(overlays[0]["x_axis"]) == len(line)
    assert 0.0 <= overlays[0]["x1"] <= 1.0
    assert 0.0 <= overlays[0]["x2"] <= 1.0

    line_data = LineData(data=line, x_axis=np.linspace(0, 1, 100))
    table2, _ = node.process(line_data, x1=0.25, y1=0.5, x2=0.75, y2=0.5)
    assert len(table2) == 6

    field = DataField(
        data=np.arange(100, dtype=np.float64).reshape(10, 10),
        xreal=2.0, yreal=4.0, si_unit_xy="um", si_unit_z="nm",
    )
    overlays.clear()
    table3, _ = node.process(field, x1=0.2, y1=0.25, x2=0.7, y2=0.75)
    assert len(table3) == 9
    field_rows = {row["quantity"]: row for row in table3}
    assert field_rows["dx"]["unit"] == "um"
    assert field_rows["dy"]["unit"] == "um"
    assert field_rows["dz"]["unit"] == "nm"
    assert np.isclose(field_rows["dx"]["value"], 1.0)
    assert np.isclose(field_rows["dy"]["value"], 2.0)
    assert len(overlays) == 1
    assert overlays[0]["kind"] == "cursor_points"
    assert overlays[0]["image"].startswith("data:image/png;base64,")

    Cursors._broadcast_overlay_fn = None