from types import SimpleNamespace

import pytest

from openpilot.system.ui.lib import text_measure, wrap_text
from openpilot.system.ui.lib.lru_cache import LRUCache


@pytest.fixture(autouse=True)
def _clear_text_caches():
  text_measure._cache.clear()
  wrap_text._cache.clear()
  yield
  text_measure._cache.clear()
  wrap_text._cache.clear()


def _fake_font(font_id: int = 1):
  return SimpleNamespace(texture=SimpleNamespace(id=font_id))


def test_measure_cache_hits_and_is_bounded(monkeypatch):
  calls = []

  def fake_measure(font, text, font_size, spacing):
    calls.append((font.texture.id, text, font_size, spacing))
    return SimpleNamespace(x=float(len(text)), y=1.0)

  monkeypatch.setattr(text_measure, "font_fallback", lambda font: font)
  monkeypatch.setattr(text_measure.rl, "measure_text_ex", fake_measure)

  font = _fake_font()

  first = text_measure.measure_text_cached(font, "hello", 10)
  second = text_measure.measure_text_cached(font, "hello", 10)
  assert second is first
  assert len(calls) == 1

  for i in range(text_measure._CACHE_MAXSIZE + 50):
    text_measure.measure_text_cached(font, f"text-{i}", 10)

  assert len(text_measure._cache) == text_measure._CACHE_MAXSIZE

  calls.clear()
  evicted = text_measure.measure_text_cached(font, "hello", 10)
  assert len(calls) == 1
  assert evicted is not first
  assert (evicted.x, evicted.y) == (first.x, first.y)


def test_wrap_cache_hits_and_is_bounded(monkeypatch):
  monkeypatch.setattr(wrap_text, "font_fallback", lambda font: font)
  monkeypatch.setattr(wrap_text, "measure_text_cached", lambda font, text, font_size, spacing=0: SimpleNamespace(x=float(len(text)), y=1.0))

  font = _fake_font()

  first = wrap_text.wrap_text(font, "some words here", 20, 1000)
  second = wrap_text.wrap_text(font, "some words here", 20, 1000)
  assert second is first

  for i in range(wrap_text._CACHE_MAXSIZE + 25):
    wrap_text.wrap_text(font, f"unique text {i}", 20, 1000)

  assert len(wrap_text._cache) == wrap_text._CACHE_MAXSIZE


def test_lru_reads_and_updates_refresh_recency():
  cache = LRUCache(2)
  cache['first'], cache['second'] = 1, 2
  assert cache.get('first') == 1
  cache['third'] = 3
  assert 'second' not in cache
  cache['first'] = 4
  cache['fourth'] = 5
  assert 'third' not in cache
  assert cache['first'] == 4
  assert cache.get('missing', 6) == 6
  assert len(cache) == 2
  cache.clear()
  assert len(cache) == 0
  with pytest.raises(ValueError):
    LRUCache(0)