from __future__ import annotations

from dpg_map.sizing import SizeMeasurement, apply_size_measurement, effective_draw_size
from dpg_map.state import DirtyFlags, create_map_state


def test_size_measurement_tracks_last_nonzero_size() -> None:
    state = create_map_state(tag="size-last-nonzero")

    first = apply_size_measurement(state, SizeMeasurement(width=640, height=360, visible=True))
    hidden = apply_size_measurement(state, SizeMeasurement(width=0, height=0, visible=False))

    assert first.changed is True
    assert state.measured_width == 0
    assert state.measured_height == 0
    assert state.last_nonzero_width == 640
    assert state.last_nonzero_height == 360
    assert hidden.became_hidden is True
    assert effective_draw_size(state) == (640, 360)


def test_zero_size_does_not_permanently_collapse_map() -> None:
    state = create_map_state(tag="size-reappears")

    apply_size_measurement(state, SizeMeasurement(width=500, height=300, visible=True))
    apply_size_measurement(state, SizeMeasurement(width=0, height=0, visible=False))
    update = apply_size_measurement(state, SizeMeasurement(width=700, height=450, visible=True))

    assert update.became_visible is True
    assert update.effective_width == 700
    assert update.effective_height == 450
    assert state.last_nonzero_width == 700
    assert state.last_nonzero_height == 450


def test_resize_marks_size_dirty() -> None:
    state = create_map_state(tag="size-dirty")
    state.dirty = DirtyFlags.NONE

    apply_size_measurement(state, SizeMeasurement(width=320, height=240, visible=True))

    assert state.dirty & DirtyFlags.SIZE
    assert state.dirty & DirtyFlags.TILES
    assert state.dirty & DirtyFlags.OVERLAYS