from pathlib import Path

import numpy
import pytest
from numpy.testing import assert_allclose

from ..file import gdsii
from ..file.gdsii import lazy as gdsii_lazy
from ..pattern import Pattern
from ..library import Library, OverlayLibrary


def _make_lazy_port_library() -> Library:
    lib = Library()

    leaf = Pattern()
    leaf.label(layer=(10, 0), string='A:type1 0', offset=(5, 0))
    lib['leaf'] = leaf

    child = Pattern()
    child.ref('leaf', offset=(10, 20), rotation=numpy.pi / 2)
    lib['child'] = child

    top = Pattern()
    top.ref('child', offset=(100, 200))
    lib['top'] = top

    return lib


def test_gdsii_lazy_source_exposes_order_and_graph_without_materializing(tmp_path: Path) -> None:
    gds_file = tmp_path / 'lazy_source.gds'
    src = _make_lazy_port_library()
    gdsii.writefile(src, gds_file, meters_per_unit=1e-9, library_name='classic-lazy')

    lib, info = gdsii_lazy.readfile(gds_file)

    assert info['name'] == 'classic-lazy'
    assert lib.source_order() == ('leaf', 'child', 'top')
    assert lib.child_graph(dangling='ignore') == {
        'leaf': set(),
        'child': {'leaf'},
        'top': {'child'},
    }
    assert not lib._cache

    child = lib['child']
    assert list(child.refs.keys()) == ['leaf']
    assert set(lib._cache) == {'child'}


def test_gdsii_lazy_ports_view_keeps_raw_source_unmodified(tmp_path: Path) -> None:
    gds_file = tmp_path / 'lazy_ports.gds'
    src = _make_lazy_port_library()
    gdsii.writefile(src, gds_file, meters_per_unit=1e-9, library_name='classic-ports')

    raw, _ = gdsii_lazy.readfile(gds_file)
    processed = raw.with_ports_from_data(layers=[(10, 0)], max_depth=2)

    top = processed['top']
    assert set(top.ports) == {'A'}
    assert_allclose(top.ports['A'].offset, [110, 225], atol=1e-10)
    assert not raw._cache

    raw_top = raw['top']
    assert not raw_top.ports


def test_gdsii_lazy_overlay_add_source_stays_lazy_for_processed_view(tmp_path: Path) -> None:
    gds_file = tmp_path / 'lazy_overlay.gds'
    src = _make_lazy_port_library()
    gdsii.writefile(src, gds_file, meters_per_unit=1e-9, library_name='classic-overlay')

    raw, _ = gdsii_lazy.readfile(gds_file)
    processed = raw.with_ports_from_data(layers=[(10, 0)], max_depth=2)

    overlay = OverlayLibrary()
    overlay.add_source(processed)

    assert not raw._cache
    assert not processed._cache

    abstract = overlay.abstract('top')
    assert set(abstract.ports) == {'A'}


def test_gdsii_lazy_overlay_add_source_can_rename_every_source_cell() -> None:
    src = _make_lazy_port_library()
    overlay = OverlayLibrary()

    rename_map = overlay.add_source(
        src,
        rename_theirs=lambda _lib, name: f'mapped_{name}',
        rename_when='always',
    )

    assert rename_map == {
        'leaf': 'mapped_leaf',
        'child': 'mapped_child',
        'top': 'mapped_top',
    }
    assert tuple(overlay.keys()) == ('mapped_leaf', 'mapped_child', 'mapped_top')
    assert 'mapped_leaf' in overlay['mapped_child'].refs


def test_gdsii_lazy_overlay_add_source_rename_when_validation() -> None:
    src = _make_lazy_port_library()

    with pytest.raises(TypeError, match='rename_theirs'):
        OverlayLibrary().add_source(src, rename_when='always')

    with pytest.raises(ValueError, match='rename mode'):
        OverlayLibrary().add_source(src, rename_when='sometimes')   # type: ignore[arg-type]


def test_gdsii_lazy_processed_write_roundtrips_without_explicit_units(tmp_path: Path) -> None:
    gds_file = tmp_path / 'lazy_roundtrip.gds'
    src = _make_lazy_port_library()
    gdsii.writefile(src, gds_file, meters_per_unit=1e-9, library_name='classic-roundtrip')

    raw, _ = gdsii_lazy.readfile(gds_file)
    processed = raw.with_ports_from_data(layers=[(10, 0)], max_depth=2)

    out_file = tmp_path / 'lazy_roundtrip_out.gds'
    gdsii_lazy.writefile(processed, out_file)

    assert out_file.read_bytes() == gds_file.read_bytes()


def test_gdsii_removed_closure_based_lazy_loader() -> None:
    assert not hasattr(gdsii, 'load_library')
    assert not hasattr(gdsii, 'load_libraryfile')