from dataclasses import dataclass
from typing import Any


@dataclass(frozen=True)
class RasterResult:
    uri: str
    metadata: dict[str, Any]


def compute_viewshed(
    observer: object,
    radius_m: float,
    target_h: float,
    surface: str,
    k: float,
) -> RasterResult:
    raise NotImplementedError(
        "Viewshed requires WhiteboxTools or gdal_viewshed integration in a later stage"
    )