# layer/metadata.py

def get_layer_type(layer) -> str:
    if layer is None:
        return "unknown"

    layer_type = getattr(layer, "layer_type", None)
    if layer_type is not None:
        return str(layer_type)

    try:
        if callable(getattr(layer, "isSpatial", None)):
            return "vector" if layer.isSpatial() else "table"
    except Exception:
        pass

    return "unknown"


def get_layer_crs(layer) -> str:
    if layer is None:
        return "None"

    crs = getattr(layer, "crs", None)
    if crs is not None and not callable(crs):
        if isinstance(crs, str):
            return crs
        return "None"

    try:
        crs_obj = layer.crs()
        authid = getattr(crs_obj, "authid", None)
        if callable(authid):
            value = authid()
            if isinstance(value, str):
                return value
    except Exception:
        pass

    return "None"



def get_layer_fields(layer) -> list[str]:
    if layer is None:
        return []

    fields = getattr(layer, "fields", None)
    if fields is not None and not callable(fields):
        return list(fields)

    try:
        f = layer.fields()
        if callable(getattr(f, "names", None)):
            return list(f.names())
        return list(f)
    except Exception:
        return []


def get_layer_source(layer) -> str:
    if layer is None:
        return "None"

    source = getattr(layer, "source", None)
    if source is not None and not callable(source):
        return str(source)

    try:
        return layer.source() or "None"
    except Exception:
        return "None"


def is_layer_editable(layer) -> bool:
    if layer is None:
        return False

    editable = getattr(layer, "editable", None)
    if editable is not None:
        return bool(editable)

    try:
        is_editable = getattr(layer, "isEditable", None)
        if callable(is_editable):
            return bool(is_editable())
    except Exception:
        pass

    return False