import unittest
import numpy as np

from NodeSlicer.core.pdf_exporter.sizing import (
    compute_grid_steps,
    compute_effective_stroke_and_font,
    LegendSizing,
    SA2Sizing,
    MM_TO_PT,
)


class TestSizingLogic(unittest.TestCase):

    def test_compute_grid_steps_small_object(self):
        # 20mm x 15mm object
        main_step, minor_step = compute_grid_steps(20.0, 15.0)
        self.assertEqual(main_step, 1.0)
        self.assertEqual(minor_step, 0.1)

    def test_compute_grid_steps_medium_object(self):
        # 120mm x 80mm object
        main_step, minor_step = compute_grid_steps(120.0, 80.0)
        self.assertEqual(main_step, 10.0)
        self.assertEqual(minor_step, 1.0)

    def test_compute_effective_stroke_and_font_defaults(self):
        # 2mm object with minor_step = 0.01mm
        line_w_pt, font_size_pt = compute_effective_stroke_and_font(0.0, 0.0, 0.01)
        # Should scale line width down proportionally for millimetric scale
        self.assertAlmostEqual(line_w_pt, 0.01 * 0.05 * MM_TO_PT, places=6)
        self.assertAlmostEqual(font_size_pt, 0.01 * MM_TO_PT, places=6)

    def test_legend_sizing_scaling(self):
        leg = LegendSizing(10.0, 1.0, 1.0, 8.0)
        self.assertGreater(leg.y_axis_height_mm, leg.major_tick_mm)
        self.assertGreater(leg.arrow_len_pt, 0)
        self.assertGreater(leg.arrow_half_w_pt, 0)

    def test_sa2_sizing_millimetric_scale(self):
        # 2mm x 1.5mm millimetric scale object
        sa2 = SA2Sizing(2.0, 1.5, 0.0014, 0.028)
        # For a 1.5mm/2mm millimetric object, offset should be fine (0.15mm)
        self.assertAlmostEqual(sa2.offset_mm, 0.15, places=3)
        self.assertAlmostEqual(sa2.ext_overhang_mm, 0.03, places=3)

        slant, leader = sa2.get_hole_callout_lengths(0.5)
        self.assertAlmostEqual(slant, 0.15, places=3)
        self.assertAlmostEqual(leader, 0.20, places=3)