"""
Tests for pointer interaction on EreaderLayoutManager (R7).

concrete/interaction_handler.py was 310 lines reachable only from
examples/07_pressed_state_demo.py - no library code, no tests. These cover the
wiring; the press/hover state on the elements themselves lives in
tests/concrete/.
"""

import pytest
from PIL import Image

from pyWebLayout.io.readers.html_extraction import parse_html_string
from pyWebLayout.layout.ereader_manager import EreaderLayoutManager


@pytest.fixture
def manager(tmp_path):
    blocks = parse_html_string(
        '<p>Tap <a href="action:go">this link</a> please.</p>'
        '<p>' + " ".join(f"w{i}" for i in range(400)) + '</p>')
    manager = EreaderLayoutManager(blocks, page_size=(400, 600),
                                   document_id="interaction",
                                   bookmarks_dir=str(tmp_path))
    yield manager
    manager.shutdown()


@pytest.fixture
def link_point(manager):
    """A page coordinate that lands on the interactive link."""
    page = manager.get_current_page()
    page.render()
    for y in range(0, 120, 2):
        for x in range(0, 400, 2):
            result = page.query_point((x, y))
            if result is not None and result.is_interactive:
                return (x, y)
    pytest.fail("fixture document rendered no interactive element")


EMPTY_POINT = (399, 599)


class TestHover:
    def test_hovering_an_element_produces_a_frame(self, manager, link_point):
        assert isinstance(manager.handle_hover(link_point), Image.Image)

    def test_hovering_the_same_element_again_reports_no_change(self, manager, link_point):
        manager.handle_hover(link_point)

        assert manager.handle_hover(link_point) is None, \
            "an unchanged hover should not force the caller to redraw"

    def test_moving_off_the_element_clears_the_hover(self, manager, link_point):
        manager.handle_hover(link_point)

        assert isinstance(manager.handle_hover(EMPTY_POINT), Image.Image)


class TestPress:
    def test_pressing_an_element_produces_a_frame(self, manager, link_point):
        assert isinstance(manager.handle_touch_down(link_point), Image.Image)

    def test_pressing_empty_space_does_nothing(self, manager):
        manager.get_current_page().render()

        assert manager.handle_touch_down(EMPTY_POINT) is None

    def test_release_runs_the_link_action(self, manager, link_point):
        manager.handle_touch_down(link_point)

        frame, result = manager.handle_touch_up(link_point)

        assert isinstance(frame, Image.Image)
        assert result == "action:go"

    def test_release_without_a_press_is_a_no_op(self, manager):
        manager.get_current_page().render()

        assert manager.handle_touch_up(EMPTY_POINT) == (None, None)

    def test_a_full_press_release_cycle_leaves_no_state(self, manager, link_point):
        manager.handle_touch_down(link_point)
        manager.handle_touch_up(link_point)

        assert manager.handle_touch_up(link_point) == (None, None)


class TestStateFollowsTheDisplayedPage:
    def test_navigating_rebinds_the_state_machine(self, manager, link_point):
        before = manager._interaction_state()

        manager.next_page()

        assert manager._interaction_state() is not before, \
            "press state belongs to one rendered page"

    def test_state_survives_repeated_access_on_one_page(self, manager, link_point):
        assert manager._interaction_state() is manager._interaction_state()

    def test_reset_is_safe_before_any_interaction(self, manager):
        manager.reset_interaction_state()  # must not raise

    def test_reset_clears_a_pending_press(self, manager, link_point):
        manager.handle_touch_down(link_point)

        manager.reset_interaction_state()

        assert manager.handle_touch_up(link_point) == (None, None)


class TestPressedRenderingRegression:
    """
    LinkText.render passed [origin, origin + size] - two numpy arrays - to
    PIL's draw.rectangle, which needs a flat four-scalar box. Rendering any
    hovered or pressed link raised TypeError. Nothing caught it because the
    only caller was an example.
    """

    def test_rendering_a_hovered_link_does_not_raise(self, manager, link_point):
        manager.handle_hover(link_point)

        assert isinstance(manager.get_current_page().render(), Image.Image)

    def test_rendering_a_pressed_link_does_not_raise(self, manager, link_point):
        manager.handle_touch_down(link_point)

        assert isinstance(manager.get_current_page().render(), Image.Image)