# Copyright (c) 2020 Ultimaker B.V.
# Cura is released under the terms of the LGPLv3 or higher.

import numpy
from string import Formatter
from enum import IntEnum
import time
from typing import Any, cast, Dict, List, Optional, Set
import re
import Arcus #For typing.
from PyQt5.QtCore import QCoreApplication

from UM.Job import Job
from UM.Logger import Logger
from UM.Scene.SceneNode import SceneNode
from UM.Settings.ContainerStack import ContainerStack #For typing.
from UM.Settings.InstanceContainer import InstanceContainer
from UM.Settings.Interfaces import ContainerInterface
from UM.Settings.SettingDefinition import SettingDefinition
from UM.Settings.SettingRelation import SettingRelation #For typing.

from UM.Scene.Iterator.DepthFirstIterator import DepthFirstIterator
from UM.Scene.Scene import Scene #For typing.
from UM.Settings.Validator import ValidatorState
from UM.Settings.SettingRelation import RelationType

from cura.CuraApplication import CuraApplication
from cura.Scene.CuraSceneNode import CuraSceneNode
from cura.OneAtATimeIterator import OneAtATimeIterator
from cura.Settings.ExtruderManager import ExtruderManager


NON_PRINTING_MESH_SETTINGS = ["anti_overhang_mesh", "infill_mesh", "cutting_mesh"]


class StartJobResult(IntEnum):
    Finished = 1
    Error = 2
    SettingError = 3
    NothingToSlice = 4
    MaterialIncompatible = 5
    BuildPlateError = 6
    ObjectSettingError = 7 #When an error occurs in per-object settings.
    ObjectsWithDisabledExtruder = 8


class GcodeStartEndFormatter(Formatter):
    """Formatter class that handles token expansion in start/end gcode"""

    def __init__(self, default_extruder_nr: int = -1) -> None:
        super().__init__()
        self._default_extruder_nr = default_extruder_nr

    def get_value(self, key: str, args: str, kwargs: dict) -> str: #type: ignore # [CodeStyle: get_value is an overridden function from the Formatter class]
        # The kwargs dictionary contains a dictionary for each stack (with a string of the extruder_nr as their key),
        # and a default_extruder_nr to use when no extruder_nr is specified

        extruder_nr = self._default_extruder_nr

        key_fragments = [fragment.strip() for fragment in key.split(",")]
        if len(key_fragments) == 2:
            try:
                extruder_nr = int(key_fragments[1])
            except ValueError:
                try:
                    extruder_nr = int(kwargs["-1"][key_fragments[1]]) # get extruder_nr values from the global stack #TODO: How can you ever provide the '-1' kwarg?
                except (KeyError, ValueError):
                    # either the key does not exist, or the value is not an int
                    Logger.log("w", "Unable to determine stack nr '%s' for key '%s' in start/end g-code, using global stack", key_fragments[1], key_fragments[0])
        elif len(key_fragments) != 1:
            Logger.log("w", "Incorrectly formatted placeholder '%s' in start/end g-code", key)
            return "{" + key + "}"

        key = key_fragments[0]

        default_value_str = "{" + key + "}"
        value = default_value_str
        # "-1" is global stack, and if the setting value exists in the global stack, use it as the fallback value.
        if key in kwargs["-1"]:
            value = kwargs["-1"][key]
        if str(extruder_nr) in kwargs and key in kwargs[str(extruder_nr)]:
            value = kwargs[str(extruder_nr)][key]

        if value == default_value_str:
            Logger.log("w", "Unable to replace '%s' placeholder in start/end g-code", key)

        return value


class StartSliceJob(Job):
    """Job class that builds up the message of scene data to send to CuraEngine."""

    def __init__(self, slice_message: Arcus.PythonMessage) -> None:
        super().__init__()

        self._scene = CuraApplication.getInstance().getController().getScene() #type: Scene
        self._slice_message = slice_message #type: Arcus.PythonMessage
        self._is_cancelled = False #type: bool
        self._build_plate_number = None #type: Optional[int]

        self._all_extruders_settings = None #type: Optional[Dict[str, Any]] # cache for all setting values from all stacks (global & extruder) for the current machine

    def getSliceMessage(self) -> Arcus.PythonMessage:
        return self._slice_message

    def setBuildPlate(self, build_plate_number: int) -> None:
        self._build_plate_number = build_plate_number

    def _checkStackForErrors(self, stack: ContainerStack) -> bool:
        """Check if a stack has any errors."""

        """returns true if it has errors, false otherwise."""

        top_of_stack = cast(InstanceContainer, stack.getTop())  # Cache for efficiency.
        changed_setting_keys = top_of_stack.getAllKeys()

        # Add all relations to changed settings as well.
        for key in top_of_stack.getAllKeys():
            instance = top_of_stack.getInstance(key)
            if instance is None:
                continue
            self._addRelations(changed_setting_keys, instance.definition.relations)
            Job.yieldThread()

        for changed_setting_key in changed_setting_keys:
            validation_state = stack.getProperty(changed_setting_key, "validationState")

            if validation_state is None:
                definition = cast(SettingDefinition, stack.getSettingDefinition(changed_setting_key))
                validator_type = SettingDefinition.getValidatorForType(definition.type)
                if validator_type:
                    validator = validator_type(changed_setting_key)
                    validation_state = validator(stack)
            if validation_state in (
            ValidatorState.Exception, ValidatorState.MaximumError, ValidatorState.MinimumError, ValidatorState.Invalid):
                Logger.log("w", "Setting %s is not valid, but %s. Aborting slicing.", changed_setting_key, validation_state)
                return True
            Job.yieldThread()

        return False

    def run(self) -> None:
        """Runs the job that initiates the slicing."""

        if self._build_plate_number is None:
            self.setResult(StartJobResult.Error)
            return

        stack = CuraApplication.getInstance().getGlobalContainerStack()
        if not stack:
            self.setResult(StartJobResult.Error)
            return

        # Don't slice if there is a setting with an error value.
        if CuraApplication.getInstance().getMachineManager().stacksHaveErrors:
            self.setResult(StartJobResult.SettingError)
            return

        if CuraApplication.getInstance().getBuildVolume().hasErrors():
            self.setResult(StartJobResult.BuildPlateError)
            return

        # Wait for error checker to be done.
        while CuraApplication.getInstance().getMachineErrorChecker().needToWaitForResult:
            time.sleep(0.1)

        if CuraApplication.getInstance().getMachineErrorChecker().hasError:
            self.setResult(StartJobResult.SettingError)
            return

        # Don't slice if the buildplate or the nozzle type is incompatible with the materials
        if not CuraApplication.getInstance().getMachineManager().variantBuildplateCompatible and \
                not CuraApplication.getInstance().getMachineManager().variantBuildplateUsable:
            self.setResult(StartJobResult.MaterialIncompatible)
            return

        for extruder_stack in stack.extruderList:
            material = extruder_stack.findContainer({"type": "material"})
            if not extruder_stack.isEnabled:
                continue
            if material:
                if material.getMetaDataEntry("compatible") == False:
                    self.setResult(StartJobResult.MaterialIncompatible)
                    return

        # Don't slice if there is a per object setting with an error value.
        for node in DepthFirstIterator(self._scene.getRoot()):
            if not isinstance(node, CuraSceneNode) or not node.isSelectable():
                continue

            if self._checkStackForErrors(node.callDecoration("getStack")):
                self.setResult(StartJobResult.ObjectSettingError)
                return

        # Remove old layer data.
        for node in DepthFirstIterator(self._scene.getRoot()):
            if node.callDecoration("getLayerData") and node.callDecoration("getBuildPlateNumber") == self._build_plate_number:
                # Singe we walk through all nodes in the scene, they always have a parent.
                cast(SceneNode, node.getParent()).removeChild(node)
                break

        # Get the objects in their groups to print.
        object_groups = []
        if stack.getProperty("print_sequence", "value") == "one_at_a_time":
            for node in OneAtATimeIterator(self._scene.getRoot()):
                temp_list = []

                # Filter on current build plate
                build_plate_number = node.callDecoration("getBuildPlateNumber")
                if build_plate_number is not None and build_plate_number != self._build_plate_number:
                    continue

                children = node.getAllChildren()
                children.append(node)
                for child_node in children:
                    mesh_data = child_node.getMeshData()
                    if mesh_data and mesh_data.getVertices() is not None:
                        temp_list.append(child_node)

                if temp_list:
                    object_groups.append(temp_list)
                Job.yieldThread()
            if len(object_groups) == 0:
                Logger.log("w", "No objects suitable for one at a time found, or no correct order found")
        else:
            temp_list = []
            has_printing_mesh = False
            for node in DepthFirstIterator(self._scene.getRoot()):
                mesh_data = node.getMeshData()
                if node.callDecoration("isSliceable") and mesh_data and mesh_data.getVertices() is not None:
                    is_non_printing_mesh = bool(node.callDecoration("isNonPrintingMesh"))

                    # Find a reason not to add the node
                    if node.callDecoration("getBuildPlateNumber") != self._build_plate_number:
                        continue
                    if getattr(node, "_outside_buildarea", False) and not is_non_printing_mesh:
                        continue

                    temp_list.append(node)
                    if not is_non_printing_mesh:
                        has_printing_mesh = True

                Job.yieldThread()

            # If the list doesn't have any model with suitable settings then clean the list
            # otherwise CuraEngine will crash
            if not has_printing_mesh:
                temp_list.clear()

            if temp_list:
                object_groups.append(temp_list)

        global_stack = CuraApplication.getInstance().getGlobalContainerStack()
        if not global_stack:
            return
        extruders_enabled = [stack.isEnabled for stack in global_stack.extruderList]
        filtered_object_groups = []
        has_model_with_disabled_extruders = False
        associated_disabled_extruders = set()
        for group in object_groups:
            stack = global_stack
            skip_group = False
            for node in group:
                # Only check if the printing extruder is enabled for printing meshes
                is_non_printing_mesh = node.callDecoration("evaluateIsNonPrintingMesh")
                extruder_position = int(node.callDecoration("getActiveExtruderPosition"))
                if not is_non_printing_mesh and not extruders_enabled[extruder_position]:
                    skip_group = True
                    has_model_with_disabled_extruders = True
                    associated_disabled_extruders.add(extruder_position)
            if not skip_group:
                filtered_object_groups.append(group)

        if has_model_with_disabled_extruders:
            self.setResult(StartJobResult.ObjectsWithDisabledExtruder)
            associated_disabled_extruders = {p + 1 for p in associated_disabled_extruders}
            self.setMessage(", ".join(map(str, sorted(associated_disabled_extruders))))
            return

        # There are cases when there is nothing to slice. This can happen due to one at a time slicing not being
        # able to find a possible sequence or because there are no objects on the build plate (or they are outside
        # the build volume)
        if not filtered_object_groups:
            self.setResult(StartJobResult.NothingToSlice)
            return

        self._buildGlobalSettingsMessage(stack)
        self._buildGlobalInheritsStackMessage(stack)

        # Build messages for extruder stacks
        for extruder_stack in global_stack.extruderList:
            self._buildExtruderMessage(extruder_stack)

        for group in filtered_object_groups:
            group_message = self._slice_message.addRepeatedMessage("object_lists")
            parent = group[0].getParent()
            if parent is not None and parent.callDecoration("isGroup"):
                self._handlePerObjectSettings(cast(CuraSceneNode, parent), group_message)

            for object in group:
                mesh_data = object.getMeshData()
                if mesh_data is None:
                    continue
                rot_scale = object.getWorldTransformation().getTransposed().getData()[0:3, 0:3]
                translate = object.getWorldTransformation().getData()[:3, 3]

                # This effectively performs a limited form of MeshData.getTransformed that ignores normals.
                verts = mesh_data.getVertices()
                verts = verts.dot(rot_scale)
                verts += translate

                # Convert from Y up axes to Z up axes. Equals a 90 degree rotation.
                verts[:, [1, 2]] = verts[:, [2, 1]]
                verts[:, 1] *= -1

                obj = group_message.addRepeatedMessage("objects")
                obj.id = id(object)
                obj.name = object.getName()
                indices = mesh_data.getIndices()
                if indices is not None:
                    flat_verts = numpy.take(verts, indices.flatten(), axis=0)
                else:
                    flat_verts = numpy.array(verts)

                obj.vertices = flat_verts

                self._handlePerObjectSettings(cast(CuraSceneNode, object), obj)

                Job.yieldThread()

        self.setResult(StartJobResult.Finished)

    def cancel(self) -> None:
        super().cancel()
        self._is_cancelled = True

    def isCancelled(self) -> bool:
        return self._is_cancelled

    def setIsCancelled(self, value: bool):
        self._is_cancelled = value

    def _buildReplacementTokens(self, stack: ContainerStack) -> Dict[str, Any]:
        """Creates a dictionary of tokens to replace in g-code pieces.

        This indicates what should be replaced in the start and end g-codes.
        :param stack: The stack to get the settings from to replace the tokens with.
        :return: A dictionary of replacement tokens to the values they should be replaced with.
        """

        result = {}
        for key in stack.getAllKeys():
            result[key] = stack.getProperty(key, "value")
            Job.yieldThread()

        result["print_bed_temperature"] = result["material_bed_temperature"] # Renamed settings.
        result["print_temperature"] = result["material_print_temperature"]
        result["travel_speed"] = result["speed_travel"]
        result["time"] = time.strftime("%H:%M:%S") #Some extra settings.
        result["date"] = time.strftime("%d-%m-%Y")
        result["day"] = ["Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"][int(time.strftime("%w"))]
        result["initial_extruder_nr"] = CuraApplication.getInstance().getExtruderManager().getInitialExtruderNr()

        return result

    def _cacheAllExtruderSettings(self):
        global_stack = cast(ContainerStack, CuraApplication.getInstance().getGlobalContainerStack())

        # NB: keys must be strings for the string formatter
        self._all_extruders_settings = {
            "-1": self._buildReplacementTokens(global_stack)
        }
        QCoreApplication.processEvents()  # Ensure that the GUI does not freeze.
        for extruder_stack in ExtruderManager.getInstance().getActiveExtruderStacks():
            extruder_nr = extruder_stack.getProperty("extruder_nr", "value")
            self._all_extruders_settings[str(extruder_nr)] = self._buildReplacementTokens(extruder_stack)
            QCoreApplication.processEvents()  # Ensure that the GUI does not freeze.

    def _expandGcodeTokens(self, value: str, default_extruder_nr: int = -1) -> str:
        """Replace setting tokens in a piece of g-code.

        :param value: A piece of g-code to replace tokens in.
        :param default_extruder_nr: Stack nr to use when no stack nr is specified, defaults to the global stack
        """
        if not self._all_extruders_settings:
            self._cacheAllExtruderSettings()

        try:
            # any setting can be used as a token
            fmt = GcodeStartEndFormatter(default_extruder_nr = default_extruder_nr)
            if self._all_extruders_settings is None:
                return ""
            settings = self._all_extruders_settings.copy()
            settings["default_extruder_nr"] = default_extruder_nr
            return str(fmt.format(value, **settings))
        except:
            Logger.logException("w", "Unable to do token replacement on start/end g-code")
            return str(value)

    def _buildExtruderMessage(self, stack: ContainerStack) -> None:
        """Create extruder message from stack"""

        message = self._slice_message.addRepeatedMessage("extruders")
        message.id = int(stack.getMetaDataEntry("position"))
        if not self._all_extruders_settings:
            self._cacheAllExtruderSettings()

        if self._all_extruders_settings is None:
            return

        extruder_nr = stack.getProperty("extruder_nr", "value")
        settings = self._all_extruders_settings[str(extruder_nr)].copy()

        # Also send the material GUID. This is a setting in fdmprinter, but we have no interface for it.
        settings["material_guid"] = stack.material.getMetaDataEntry("GUID", "")

        # Replace the setting tokens in start and end g-code.
        extruder_nr = stack.getProperty("extruder_nr", "value")
        settings["machine_extruder_start_code"] = self._expandGcodeTokens(settings["machine_extruder_start_code"], extruder_nr)
        settings["machine_extruder_end_code"] = self._expandGcodeTokens(settings["machine_extruder_end_code"], extruder_nr)

        global_definition = cast(ContainerInterface, cast(ContainerStack, stack.getNextStack()).getBottom())
        own_definition = cast(ContainerInterface, stack.getBottom())

        for key, value in settings.items():
            # Do not send settings that are not settable_per_extruder.
            # Since these can only be set in definition files, we only have to ask there.
            if not global_definition.getProperty(key, "settable_per_extruder") and \
                    not own_definition.getProperty(key, "settable_per_extruder"):
                    continue
            setting = message.getMessage("settings").addRepeatedMessage("settings")
            setting.name = key
            setting.value = str(value).encode("utf-8")
            Job.yieldThread()

    def _buildGlobalSettingsMessage(self, stack: ContainerStack) -> None:
        """Sends all global settings to the engine.

        The settings are taken from the global stack. This does not include any
        per-extruder settings or per-object settings.
        """

        if not self._all_extruders_settings:
            self._cacheAllExtruderSettings()

        if self._all_extruders_settings is None:
            return

        settings = self._all_extruders_settings["-1"].copy()

        # Pre-compute material material_bed_temp_prepend and material_print_temp_prepend
        start_gcode = settings["machine_start_gcode"]
        # Remove all the comments from the start g-code
        start_gcode = re.sub(r";.+?(\n|$)", "\n", start_gcode)
        bed_temperature_settings = ["material_bed_temperature", "material_bed_temperature_layer_0"]
        pattern = r"\{(%s)(,\s?\w+)?\}" % "|".join(bed_temperature_settings) # match {setting} as well as {setting, extruder_nr}
        settings["material_bed_temp_prepend"] = re.search(pattern, start_gcode) == None
        print_temperature_settings = ["material_print_temperature", "material_print_temperature_layer_0", "default_material_print_temperature", "material_initial_print_temperature", "material_final_print_temperature", "material_standby_temperature"]
        pattern = r"\{(%s)(,\s?\w+)?\}" % "|".join(print_temperature_settings) # match {setting} as well as {setting, extruder_nr}
        settings["material_print_temp_prepend"] = re.search(pattern, start_gcode) == None

        # Replace the setting tokens in start and end g-code.
        # Use values from the first used extruder by default so we get the expected temperatures
        initial_extruder_nr = CuraApplication.getInstance().getExtruderManager().getInitialExtruderNr()
        settings["machine_start_gcode"] = self._expandGcodeTokens(settings["machine_start_gcode"], initial_extruder_nr)
        settings["machine_end_gcode"] = self._expandGcodeTokens(settings["machine_end_gcode"], initial_extruder_nr)

        # Add all sub-messages for each individual setting.
        for key, value in settings.items():
            setting_message = self._slice_message.getMessage("global_settings").addRepeatedMessage("settings")
            setting_message.name = key
            setting_message.value = str(value).encode("utf-8")
            Job.yieldThread()

    def _buildGlobalInheritsStackMessage(self, stack: ContainerStack) -> None:
        """Sends for some settings which extruder they should fallback to if not set.

        This is only set for settings that have the limit_to_extruder
        property.

        :param stack: The global stack with all settings, from which to read the
            limit_to_extruder property.
        """

        for key in stack.getAllKeys():
            extruder_position = int(round(float(stack.getProperty(key, "limit_to_extruder"))))
            if extruder_position >= 0:  # Set to a specific extruder.
                setting_extruder = self._slice_message.addRepeatedMessage("limit_to_extruder")
                setting_extruder.name = key
                setting_extruder.extruder = extruder_position
            Job.yieldThread()

    def _handlePerObjectSettings(self, node: CuraSceneNode, message: Arcus.PythonMessage):
        """Check if a node has per object settings and ensure that they are set correctly in the message

        :param node: Node to check.
        :param message: object_lists message to put the per object settings in
        """

        stack = node.callDecoration("getStack")

        # Check if the node has a stack attached to it and the stack has any settings in the top container.
        if not stack:
            return

        # Check all settings for relations, so we can also calculate the correct values for dependent settings.
        top_of_stack = stack.getTop()  # Cache for efficiency.
        changed_setting_keys = top_of_stack.getAllKeys()

        # Add all relations to changed settings as well.
        for key in top_of_stack.getAllKeys():
            instance = top_of_stack.getInstance(key)
            self._addRelations(changed_setting_keys, instance.definition.relations)
            Job.yieldThread()

        # Ensure that the engine is aware what the build extruder is.
        changed_setting_keys.add("extruder_nr")

        # Get values for all changed settings
        for key in changed_setting_keys:
            setting = message.addRepeatedMessage("settings")
            setting.name = key
            extruder = int(round(float(stack.getProperty(key, "limit_to_extruder"))))

            # Check if limited to a specific extruder, but not overridden by per-object settings.
            if extruder >= 0 and key not in changed_setting_keys:
                limited_stack = ExtruderManager.getInstance().getActiveExtruderStacks()[extruder]
            else:
                limited_stack = stack

            setting.value = str(limited_stack.getProperty(key, "value")).encode("utf-8")

            Job.yieldThread()

    def _addRelations(self, relations_set: Set[str], relations: List[SettingRelation]):
        """Recursive function to put all settings that require each other for value changes in a list

        :param relations_set: Set of keys of settings that are influenced
        :param relations: list of relation objects that need to be checked.
        """

        for relation in filter(lambda r: r.role == "value" or r.role == "limit_to_extruder", relations):
            if relation.type == RelationType.RequiresTarget:
                continue

            relations_set.add(relation.target.key)
            self._addRelations(relations_set, relation.target.relations)
