# IfcPatch - IFC patching utiliy
# Copyright (C) 2020, 2021 Dion Moult <dion@thinkmoult.com>
#
# This file is part of IfcPatch.
#
# IfcPatch 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.
#
# IfcPatch 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 IfcPatch.  If not, see <http://www.gnu.org/licenses/>.


class Patcher:
    def __init__(self, src, file, logger, output_dir=None):
        """Split an IFC model into multiple models based on building storey

        The new IFC model names will be named after the storey name in the
        format of {i}-{name}.ifc, where {i} is an ascending number starting from
        0 and {name} is the name of the storey.

        :param output_dir: Specifies an output directory where the new IFC models will be saved.
        :type output_dir: str
           
        Example:

        .. code:: python

            ifcpatch.execute({"input": model, "recipe": "SplitByBuildingStorey", "arguments": ["C:/.../output_files"]})
        """
        self.src = src
        self.file = file
        self.logger = logger
        self.output_dir = output_dir


    def patch(self):
        import ifcopenshell
        from shutil import copyfile

        storeys = self.file.by_type("IfcBuildingStorey")
        for i, storey in enumerate(storeys):
            dest = "{}-{}.ifc".format(i, storey.Name) if self.output_dir == None else "{}/{}-{}.ifc".format(self.output_dir,i, storey.Name)
            copyfile(self.src, dest)
            old_ifc = ifcopenshell.open(dest)
            new_ifc = ifcopenshell.file(schema=self.file.schema)
            if self.file.schema == "IFC2X3":
                elements = old_ifc.by_type("IfcProject") + old_ifc.by_type("IfcProduct")
            else:
                elements = old_ifc.by_type("IfcContext") + old_ifc.by_type("IfcProduct")
            inverse_elements = []
            for element in elements:
                if element.is_a("IfcElement") and not self.is_in_storey(element, storey):
                    element.Representation = None
                    continue
                if element.is_a("IfcElement"):
                    styled_rep_items = [
                        i for i in old_ifc.traverse(element) if i.is_a("IfcRepresentationItem") and i.StyledByItem
                    ]
                    [new_ifc.add(i.StyledByItem[0]) for i in styled_rep_items]
                new_ifc.add(element)
                inverse_elements.extend(old_ifc.get_inverse(element))
            for inverse_element in inverse_elements:
                new_ifc.add(inverse_element)
            for element in new_ifc.by_type("IfcElement"):
                if not self.is_in_storey(element, storey):
                    new_ifc.remove(element)
            new_ifc.write(dest)

    def is_in_storey(self, element, storey):
        return (
            element.ContainedInStructure
            and element.ContainedInStructure[0].RelatingStructure.is_a("IfcBuildingStorey")
            and element.ContainedInStructure[0].RelatingStructure.GlobalId == storey.GlobalId
        )
