Cura/cura/Machines/MaterialNode.py

# Copyright (c) 2018 Ultimaker B.V.
# Cura is released under the terms of the LGPLv3 or higher.
from typing import Optional, Dict, Any
from collections import OrderedDict
from .ContainerNode import ContainerNode


#
# A MaterialNode is a node in the material lookup tree/map/table. It contains 2 (extra) fields:
#  - material_map: a one-to-one map of "material_root_id" to material_node.
#  - children_map: the key-value map for child nodes of this node. This is used in a lookup tree.
#
#
class MaterialNode(ContainerNode):
    __slots__ = ("material_map", "children_map")

    def __init__(self, metadata: Optional[Dict[str, Any]] = None) -> None:
        super().__init__(metadata = metadata)
        self.material_map = {}  # type: Dict[str, MaterialNode] # material_root_id -> material_node

        # We overide this as we want to indicate that MaterialNodes can only contain other material nodes.
        self.children_map = OrderedDict()  # type: OrderedDict[str, "MaterialNode"]

    def getChildNode(self, child_key: str) -> Optional["MaterialNode"]:
        return self.children_map.get(child_key)