# IfcOpenShell - IFC toolkit and geometry engine
# Copyright (C) 2021 Dion Moult <dion@thinkmoult.com>
#
# This file is part of IfcOpenShell.
#
# IfcOpenShell is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# IfcOpenShell is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.

from typing import Any, Optional, Union

import numpy as np
import numpy.typing as npt

import ifcopenshell.api.owner
import ifcopenshell.util.element
import ifcopenshell.util.placement
import ifcopenshell.util.unit
from ifcopenshell.util.shape_builder import ShapeBuilder

NPArrayOfFloats = npt.NDArray[np.float64]


def edit_object_placement(
    file: ifcopenshell.file,
    product: ifcopenshell.entity_instance,
    matrix: Optional[NPArrayOfFloats] = None,
    is_si: bool = True,
    should_transform_children: bool = False,
) -> ifcopenshell.entity_instance:
    """Changes the object placement matrix of an element

    The placement matrix is a 4x4 matrix describing the location and
    orientation of an element in 3D. See
    https://docs.ifcopenshell.org/ifcopenshell-python/geometry_creation.html#object-placements
    for more details.

    This only supports local placements. Grid and linear placements are not
    supported.

    :param matrix: A 4x4 matrix in numpy. If left blank, it is the identity
        matrix (equivalent to ``np.eye(4)``).
    :param is_si: If True, the matrix is given in SI units. If false, in
        project units.
    :param should_transform_children: A child element is a nested element,
        opening, filling, etc. If True, child elements move along with the
        parent; pass True when moving an assembly (roof, furniture group, etc.)
        and you want all children to follow. If False (default), child elements
        keep their current world positions; their local placements are rewritten
        to compensate for the parent move.
    :return: The new or updated IfcLocalPlacement entity
    """
    usecase = Usecase()
    usecase.file = file
    usecase.settings = {
        "product": product,
        "matrix": matrix if matrix is not None else np.eye(4),
        "is_si": is_si,
        "should_transform_children": should_transform_children,
    }
    return usecase.execute()


class Usecase:
    file: ifcopenshell.file
    settings: dict[str, Any]

    def execute(self):
        if not hasattr(self.settings["product"], "ObjectPlacement"):
            return
        self.unit_scale = ifcopenshell.util.unit.calculate_unit_scale(self.file)
        self.builder = ShapeBuilder(self.file)

        if not self.settings["is_si"]:
            self.convert_matrix_to_si(self.settings["matrix"])

        children_settings = []
        if not self.settings["should_transform_children"]:
            children_settings = self.get_children_settings(self.settings["product"].ObjectPlacement)

        placement_rel_to = self.get_placement_rel_to()
        relative_placement = self.get_relative_placement(placement_rel_to)
        new_placement = self.file.createIfcLocalPlacement(RelativePlacement=relative_placement)

        old_placement = self.settings["product"].ObjectPlacement

        if old_placement:
            for inverse in self.file.get_inverse(old_placement):
                if inverse.is_a("IfcLocalPlacement"):
                    ifcopenshell.util.element.replace_attribute(inverse, old_placement, new_placement)

            if self.file.get_total_inverses(old_placement) == 1:
                self.settings["product"].ObjectPlacement = None
                old_placement.PlacementRelTo = None
                ifcopenshell.util.element.remove_deep2(self.file, old_placement)

        new_placement.PlacementRelTo = placement_rel_to
        self.settings["product"].ObjectPlacement = new_placement

        ifcopenshell.api.owner.update_owner_history(self.file, element=self.settings["product"])

        for settings in children_settings:
            self.settings = settings
            self.execute()

        return new_placement

    def convert_matrix_to_si(self, matrix: NPArrayOfFloats):
        matrix[0][3] *= self.unit_scale
        matrix[1][3] *= self.unit_scale
        matrix[2][3] *= self.unit_scale

    def get_placement_rel_to(self) -> Union[ifcopenshell.entity_instance, None]:
        product = self.settings["product"]
        relating_object = None

        if rels := getattr(product, "Decomposes", None):
            relating_object = rels[0].RelatingObject
        elif rels := getattr(product, "Nests", None):
            relating_object = rels[0].RelatingObject
        elif rels := getattr(product, "ContainedIn", None):
            relating_object = rels[0].RelatedElement
        elif rels := getattr(product, "VoidsElements", None):
            relating_object = rels[0].RelatingBuildingElement
        elif rels := getattr(product, "FillsVoids", None):
            relating_object = rels[0].RelatingOpeningElement
        elif rels := getattr(product, "ProjectsElements", None):
            relating_object = rels[0].RelatingElement
        # TODO: add tests when there will be adherence api
        elif rels := getattr(product, "AdheresToElement", None):
            relating_object = rels[0].RelatingElement
        elif rels := getattr(product, "ContainedInStructure", None):
            return rels[0].RelatingStructure.ObjectPlacement

        if relating_object:
            return getattr(relating_object, "ObjectPlacement", None)

    def get_children_settings(self, placement: Union[ifcopenshell.entity_instance, None]) -> list[dict]:
        if not placement:
            return []
        results = []
        # NOTE: we ignore subchildren as we already adjust position for their parent
        # therefore they're not present in `results` and `should_transform_children` should be `True`
        for referenced_placement in placement.ReferencedByPlacements:
            matrix = ifcopenshell.util.placement.get_local_placement(referenced_placement)
            for obj in referenced_placement.PlacesObject:
                if obj.is_a("IfcDistributionPort"):
                    # Although a port is technically a nested child, it is generally
                    # more intuitive that the ports always move with the parent.
                    continue
                elif obj.is_a("IfcFeatureElement"):
                    # Feature elements affect the geometry of their parent, and
                    # so logically should always move with the parent. However,
                    # subchildren (fillings) shouldn't move.
                    placement2 = obj.ObjectPlacement
                    for referenced_placement2 in placement2.ReferencedByPlacements:
                        matrix2 = ifcopenshell.util.placement.get_local_placement(referenced_placement2)
                        for obj2 in referenced_placement2.PlacesObject:
                            results.append(
                                {"product": obj2, "matrix": matrix2, "is_si": False, "should_transform_children": True}
                            )
                    continue
                results.append({"product": obj, "matrix": matrix, "is_si": False, "should_transform_children": True})
        return results

    def get_relative_placement(
        self, placement_rel_to: Union[ifcopenshell.entity_instance, None]
    ) -> ifcopenshell.entity_instance:
        if placement_rel_to:
            relating_object_matrix = ifcopenshell.util.placement.get_local_placement(placement_rel_to)
            relating_object_matrix[0][3] = self.convert_unit_to_si(relating_object_matrix[0][3])
            relating_object_matrix[1][3] = self.convert_unit_to_si(relating_object_matrix[1][3])
            relating_object_matrix[2][3] = self.convert_unit_to_si(relating_object_matrix[2][3])
        else:
            relating_object_matrix = np.eye(4)
        m = self.settings["matrix"]
        x = np.array((m[0][0], m[1][0], m[2][0]))
        z = np.array((m[0][2], m[1][2], m[2][2]))
        o = np.array((m[0][3], m[1][3], m[2][3]))
        object_matrix = ifcopenshell.util.placement.a2p(o, z, x)
        relative_placement_matrix = np.linalg.inv(relating_object_matrix) @ object_matrix
        return self.builder.create_axis2_placement_3d(
            self.convert_si_to_unit(relative_placement_matrix[:, 3][0:3]),
            relative_placement_matrix[:, 2][0:3],
            relative_placement_matrix[:, 0][0:3],
        )

    def convert_si_to_unit(self, co: NPArrayOfFloats) -> NPArrayOfFloats:
        return co / self.unit_scale

    def convert_unit_to_si(self, co: NPArrayOfFloats) -> NPArrayOfFloats:
        return co * self.unit_scale
