import gdsfactory as gf
from gdsfactory.pdk import get_grid_size
from gdsfactory.snap import is_on_grid
from gdsfactory.types import Component, ComponentReference, Optional


def is_valid_transformation(
    ref: ComponentReference, grid_size: Optional[float] = None
) -> bool:
    """Returns True if the component has valid transformations.

    Args:
        component: the component reference to check.
        grid_size: the GDS grid size, in um, defaults to active PDK.get_grid_size()
            any translations with higher resolution than this are considered invalid.
    """
    grid_size = grid_size or get_grid_size()
    nm = int(grid_size * 1e3)
    origin_is_on_grid = all(is_on_grid(x, nm) for x in ref.origin)
    rotation_is_regular = ref.rotation is None or ref.rotation % 90 == 0
    return origin_is_on_grid and rotation_is_regular


def has_valid_transformations(component: Component) -> bool:
    """Returns True if the component has valid transformations."""
    refs = component.references
    for ref in refs:
        if not is_valid_transformation(ref):
            return False
    return True


def flatten_invalid_refs(component: Component, grid_size: Optional[float] = None):
    """Flattens component references component with invalid GDS.

    transformations.

    (i.e. non-90 deg rotations or sub-grid translations).

    This is an in-place operation, so you should use it as a decorator.
    flattens only individual references with invalid transformations.

    Args:
        component: the component to fix (in place).
        grid_size: the GDS grid size, in um, defaults to active PDK.get_grid_size()
            any translations with higher resolution than this are considered invalid.
    """
    grid_size = grid_size or get_grid_size()
    nm = int(grid_size * 1e3)

    refs = component.references.copy()
    for ref in refs:
        origin_is_on_grid = all(is_on_grid(x, nm) for x in ref.origin)
        rotation_is_regular = ref.rotation is None or ref.rotation % 90 == 0
        if not origin_is_on_grid or not rotation_is_regular:
            component.flatten_reference(ref)
    return component


@gf.cell
def _demo_non_manhattan() -> Component:
    """Returns component with Manhattan snapping issues."""
    c = Component("bend")
    b = c << gf.components.bend_circular(angle=30)
    s = c << gf.components.straight(length=5)
    s.connect("o1", b.ports["o2"])
    return c


def test_flatten_invalid_refs():
    c1 = _demo_non_manhattan()
    assert not has_valid_transformations(c1)

    c2 = _demo_non_manhattan(decorator=flatten_invalid_refs)
    assert has_valid_transformations(c2)


if __name__ == "__main__":
    test_flatten_invalid_refs()
    # c = _demo_non_manhattan(decorator=flatten_invalid_refs)
    # c.show()
