# Copyright (c) 2019 Ultimaker B.V.
# Cura is released under the terms of the LGPLv3 or higher.
from typing import TYPE_CHECKING

from UM.Logger import Logger
from UM.Settings.ContainerRegistry import ContainerRegistry
from UM.Settings.Interfaces import ContainerInterface
from UM.Signal import Signal

from cura.Machines.ContainerNode import ContainerNode
from cura.Machines.MaterialNode import MaterialNode

import UM.FlameProfiler

if TYPE_CHECKING:
    from typing import Dict
    from cura.Machines.MachineNode import MachineNode


class VariantNode(ContainerNode):
    """This class represents an extruder variant in the container tree.

    The subnodes of these nodes are materials.

    This node contains materials with ALL filament diameters underneath it. The tree of this variant is not specific
    to one global stack, so because the list of materials can be different per stack depending on the compatible
    material diameter setting, we cannot filter them here. Filtering must be done in the model.
    """

    def __init__(self, container_id: str, machine: "MachineNode") -> None:
        super().__init__(container_id)
        self.machine = machine
        self.materials = {}  # type: Dict[str, MaterialNode]  # Mapping material base files to their nodes.
        self.materialsChanged = Signal()

        container_registry = ContainerRegistry.getInstance()
        self.variant_name = container_registry.findContainersMetadata(id = container_id)[0]["name"]  # Store our own name so that we can filter more easily.
        container_registry.containerAdded.connect(self._materialAdded)
        container_registry.containerRemoved.connect(self._materialRemoved)
        self._loadAll()

    @UM.FlameProfiler.profile
    def _loadAll(self) -> None:
        """(Re)loads all materials under this variant."""

        container_registry = ContainerRegistry.getInstance()

        if not self.machine.has_materials:
            self.materials["empty_material"] = MaterialNode("empty_material", variant = self)
            return  # There should not be any materials loaded for this printer.

        # Find all the materials for this variant's name.
        else:  # Printer has its own material profiles. Look for material profiles with this printer's definition.
            base_materials = container_registry.findInstanceContainersMetadata(type = "material", definition = "fdmprinter")
            printer_specific_materials = container_registry.findInstanceContainersMetadata(type = "material", definition = self.machine.container_id)
            variant_specific_materials = container_registry.findInstanceContainersMetadata(type = "material", definition = self.machine.container_id, variant_name = self.variant_name)  # If empty_variant, this won't return anything.
            materials_per_base_file = {material["base_file"]: material for material in base_materials}
            materials_per_base_file.update({material["base_file"]: material for material in printer_specific_materials})  # Printer-specific profiles override global ones.
            materials_per_base_file.update({material["base_file"]: material for material in variant_specific_materials})  # Variant-specific profiles override all of those.
            materials = list(materials_per_base_file.values())

        # Filter materials based on the exclude_materials property.
        filtered_materials = [material for material in materials if not self.machine.isExcludedMaterial(material)]

        for material in filtered_materials:
            base_file = material["base_file"]
            if base_file not in self.materials:
                self.materials[base_file] = MaterialNode(material["id"], variant = self)
                self.materials[base_file].materialChanged.connect(self.materialsChanged)
        if not self.materials:
            self.materials["empty_material"] = MaterialNode("empty_material", variant = self)

    def preferredMaterial(self, approximate_diameter: int) -> MaterialNode:
        """Finds the preferred material for this printer with this nozzle in one of the extruders.

        If the preferred material is not available, an arbitrary material is returned. If there is a configuration
        mistake (like a typo in the preferred material) this returns a random available material. If there are no
        available materials, this will return the empty material node.

        :param approximate_diameter: The desired approximate diameter of the material.

        :return: The node for the preferred material, or any arbitrary material if there is no match.
        """

        for base_material, material_node in self.materials.items():
            if self.machine.preferred_material == base_material and approximate_diameter == int(material_node.getMetaDataEntry("approximate_diameter")):
                return material_node

        # First fallback: Check if we should be checking for the 175 variant.
        if approximate_diameter == 2:
            preferred_material = self.machine.preferred_material + "_175"
            for base_material, material_node in self.materials.items():
                if preferred_material == base_material and approximate_diameter == int(material_node.getMetaDataEntry("approximate_diameter")):
                    return material_node

        # Second fallback: Choose any material with matching diameter.
        for material_node in self.materials.values():
            if material_node.getMetaDataEntry("approximate_diameter") and approximate_diameter == int(material_node.getMetaDataEntry("approximate_diameter")):
                Logger.log("w", "Could not find preferred material %s, falling back to whatever works", self.machine.preferred_material)
                return material_node

        fallback = next(iter(self.materials.values()))  # Should only happen with empty material node.
        Logger.log("w", "Could not find preferred material {preferred_material} with diameter {diameter} for variant {variant_id}, falling back to {fallback}.".format(
            preferred_material = self.machine.preferred_material,
            diameter = approximate_diameter,
            variant_id = self.container_id,
            fallback = fallback.container_id
        ))
        return fallback

    @UM.FlameProfiler.profile
    def _materialAdded(self, container: ContainerInterface) -> None:
        """When a material gets added to the set of profiles, we need to update our tree here."""

        if container.getMetaDataEntry("type") != "material":
            return  # Not interested.
        if not ContainerRegistry.getInstance().findContainersMetadata(id = container.getId()):
            # CURA-6889
            # containerAdded and removed signals may be triggered in the next event cycle. If a container gets added
            # and removed in the same event cycle, in the next cycle, the connections should just ignore the signals.
            # The check here makes sure that the container in the signal still exists.
            Logger.log("d", "Got container added signal for container [%s] but it no longer exists, do nothing.",
                       container.getId())
            return
        if not self.machine.has_materials:
            return  # We won't add any materials.
        material_definition = container.getMetaDataEntry("definition")

        base_file = container.getMetaDataEntry("base_file")
        if base_file in self.machine.exclude_materials:
            return  # Material is forbidden for this printer.
        if base_file not in self.materials:  # Completely new base file. Always better than not having a file as long as it matches our set-up.
            if material_definition != "fdmprinter" and material_definition != self.machine.container_id:
                return
            material_variant = container.getMetaDataEntry("variant_name")
            if material_variant is not None and material_variant != self.variant_name:
                return
        else:  # We already have this base profile. Replace the base profile if the new one is more specific.
            new_definition = container.getMetaDataEntry("definition")
            if new_definition == "fdmprinter":
                return  # Just as unspecific or worse.
            material_variant = container.getMetaDataEntry("variant_name")
            if new_definition != self.machine.container_id or material_variant != self.variant_name:
                return  # Doesn't match this set-up.
            original_metadata = ContainerRegistry.getInstance().findContainersMetadata(id = self.materials[base_file].container_id)[0]
            if "variant_name" in original_metadata or material_variant is None:
                return  # Original was already specific or just as unspecific as the new one.

        if "empty_material" in self.materials:
            del self.materials["empty_material"]
        self.materials[base_file] = MaterialNode(container.getId(), variant = self)
        self.materials[base_file].materialChanged.connect(self.materialsChanged)
        self.materialsChanged.emit(self.materials[base_file])

    @UM.FlameProfiler.profile
    def _materialRemoved(self, container: ContainerInterface) -> None:
        if container.getMetaDataEntry("type") != "material":
            return  # Only interested in materials.
        base_file = container.getMetaDataEntry("base_file")
        if base_file not in self.materials:
            return  # We don't track this material anyway. No need to remove it.

        original_node = self.materials[base_file]
        del self.materials[base_file]
        self.materialsChanged.emit(original_node)

        # Now a different material from the same base file may have been hidden because it was not as specific as the one we deleted.
        # Search for any submaterials from that base file that are still left.
        materials_same_base_file = ContainerRegistry.getInstance().findContainersMetadata(base_file = base_file)
        if materials_same_base_file:
            most_specific_submaterial = None
            for submaterial in materials_same_base_file:
                if submaterial["definition"] == self.machine.container_id:
                    if submaterial.get("variant_name", "empty") == self.variant_name:
                        most_specific_submaterial = submaterial
                        break  # most specific match possible
                    if submaterial.get("variant_name", "empty") == "empty":
                        most_specific_submaterial = submaterial

            if most_specific_submaterial is None:
                Logger.log("w", "Material %s removed, but no suitable replacement found", base_file)
            else:
                Logger.log("i", "Material %s (%s) overridden by %s", base_file, self.variant_name, most_specific_submaterial.get("id"))
                self.materials[base_file] = MaterialNode(most_specific_submaterial["id"], variant = self)
                self.materialsChanged.emit(self.materials[base_file])

        if not self.materials:  # The last available material just got deleted and there is nothing with the same base file to replace it.
            self.materials["empty_material"] = MaterialNode("empty_material", variant = self)
            self.materialsChanged.emit(self.materials["empty_material"])