import inspect
from typing import Any, Optional


def get_nested_attr(
    module: ..., 
    attr_path: str,
) -> Any | None:
    """Loop through nested attributes."""
    x = module
    for attr in attr_path.split("."):
        x = getattr(x, attr, None)
    return x


def get_callable_names(
    prefix: str, 
    module: ..., 
    max_depth: int = 3, 
    depth: int = 0,
    include: Optional[set[str]] = None,
) -> list[str]:
    """
    Recursively retrieve the names of all callables in a given module.
    """
    callable_names = []
    if depth > max_depth:
        return callable_names
    for attr in dir(module):
        if (
            attr.startswith("_") or
            attr in {"model_fields", "model_computed_fields"} or
            include and attr not in include
        ):
            continue
        try:
            value = getattr(module, attr)
        except Exception:
            continue
        full_name = f"{prefix}.{attr}"
        if callable(value):
            callable_names.append(full_name)
        elif hasattr(value, "__dict__") or hasattr(value, "__module__"):
            callable_names.extend(
                get_callable_names(
                    full_name,
                    value,
                    max_depth,
                    depth + 1
                ) # Recurse
            )
    return callable_names


def get_callable_params(
    prefix: str, 
    module: ...,
    callable_name: str
) -> list[dict[str, str]]:
    """
    Get parameter names and default values for a given callable.
    """
    callable = get_nested_attr(
        module, 
        callable_name.replace(f"{prefix}.", "", 1)
    )
    if not callable:
        return []
    try:
        sig = inspect.signature(callable)
        params = []
        for name, param in sig.parameters.items():
            if name == "self":
                continue
            default = (
                param.default if
                param.default is not inspect.Parameter.empty else 
                ""
            )
            kind = param.kind
            params.append({
                "name": name,
                "default": default, 
                "kind": kind
            })
        return params
    except Exception:
        return []


def test_callable(
    prefix: str,
    module: ...,
    callable_name: str,
    *args, **kwargs
) -> str:
    """Test a given callable and return the output."""

    callable = get_nested_attr(
        module,
        callable_name.replace("_", ".").replace(f"{prefix}.", "", 1)
    )
    if not callable:
        return f"Callable '{callable_name}' not found."
    try:
        result = callable(*args, **kwargs)
        return result
    except TypeError as e:
        return f"Callable '{callable_name}' requires arguments: {e}"
    except Exception as e:
        return f"Error running '{callable_name}': {e}"


def generate_callable_guides(prefix: str, module: ..., callable_names: list[str]) -> list[str]:
    """
    Generate callable reference guides from docstrings, parameters, and
    parameter/return types.
    """
    guide = []
    for callable in callable_names:
        callable = get_nested_attr(module, callable.replace(f"{prefix}.", "", 1))
        doc = callable.__doc__ if callable and hasattr(callable, "__doc__") else "No docstring available."
        guide.append(f"{doc}")
    return guide