# IfcOpenShell - IFC toolkit and geometry engine
# Copyright (C) 2021 Thomas Krijnen <thomas@aecgeeks.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 __future__ import annotations
import os
import re
import numbers
import zipfile
import functools
import ifcopenshell
from pathlib import Path
from typing import Optional, Any, Union, Callable, Generator, Literal, TYPE_CHECKING

from . import ifcopenshell_wrapper
from .entity_instance import entity_instance

if TYPE_CHECKING:
    import ifcopenshell.util.schema

HEADER_FIELDS = {
    "file_description": [
        "description",
        "implementation_level",
    ],
    "file_name": [
        "name",
        "time_stamp",
        "author",
        "organization",
        "preprocessor_version",
        "originating_system",
        "authorization",
    ],
}


class Transaction:
    def __init__(self, ifc_file: file):
        self.file: file = ifc_file
        self.operations = []
        self.is_batched = False
        self.batch_delete_index = 0
        self.batch_delete_ids = set()
        self.batch_inverses = []

    def serialise_entity_instance(self, element: ifcopenshell.entity_instance) -> dict[str, Any]:
        info = element.get_info()
        for key, value in info.items():
            info[key] = self.serialise_value(element, value)
        return info

    def serialise_value(self, element, value):
        return element.walk(
            lambda v: isinstance(v, entity_instance),
            lambda v: {"id": v.id()} if v.id() else {"type": v.is_a(), "value": v.wrappedValue},
            value,
        )

    def unserialise_value(self, element, value):
        return element.walk(
            lambda v: isinstance(v, dict),
            lambda v: self.file.by_id(v["id"]) if v.get("id") else self.file.create_entity(v["type"], v["value"]),
            value,
        )

    def batch(self) -> None:
        self.is_batched = True
        self.batch_delete_index = len(self.operations)
        self.batch_delete_ids = set()
        self.batch_inverses = []

    def unbatch(self) -> None:
        for inverses in self.batch_inverses:
            if inverses:
                self.operations.insert(self.batch_delete_index, {"action": "batch_delete", "inverses": inverses})
        self.is_batched = False
        self.batch_delete_index = 0
        self.batch_delete_ids = set()
        self.batch_inverses = []

    def store_create(self, element: ifcopenshell.entity_instance) -> None:
        if element.id():
            self.operations.append({"action": "create", "value": self.serialise_entity_instance(element)})

    def store_edit(self, element: ifcopenshell.entity_instance, index: int, value: Any) -> None:
        if element.id():
            self.operations.append(
                {
                    "action": "edit",
                    "id": element.id(),
                    "index": index,
                    "old": self.serialise_value(element, element[index]),
                    "new": self.serialise_value(element, value),
                }
            )

    def store_delete(self, element: ifcopenshell.entity_instance) -> None:
        inverses = {}
        if self.is_batched:
            if element.id() not in self.batch_delete_ids:
                self.batch_inverses.append(self.get_element_inverses(element))
            self.batch_delete_ids.add(element.id())
        else:
            inverses = self.get_element_inverses(element)
        self.operations.append(
            {"action": "delete", "inverses": inverses, "value": self.serialise_entity_instance(element)}
        )

    def get_element_inverses(self, element):
        inverses = {}
        for inverse in self.file.get_inverse(element):
            inverse_references = []
            for i, attribute in enumerate(inverse):
                if self.has_element_reference(attribute, element):
                    inverse_references.append((i, self.serialise_value(inverse, attribute)))
            inverses[inverse.id()] = inverse_references
        return inverses

    def has_element_reference(self, value: Any, element: ifcopenshell.entity_instance) -> bool:
        if isinstance(value, (tuple, list)):
            for v in value:
                if self.has_element_reference(v, element):
                    return True
            return False
        return value == element

    def rollback(self) -> None:
        for operation in self.operations[::-1]:
            if operation["action"] == "create":
                element = self.file.by_id(operation["value"]["id"])
                if hasattr(element, "GlobalId") and element.GlobalId is None:
                    # hack, otherwise ifcopenshell gets upset
                    element.GlobalId = "x"
                self.file.remove(element)
            elif operation["action"] == "edit":
                element = self.file.by_id(operation["id"])
                try:
                    element[operation["index"]] = self.unserialise_value(element, operation["old"])
                except:
                    # Catch discrepancy where IfcOpenShell creates but doesn't allow editing of invalid values
                    pass
            elif operation["action"] == "delete":
                e = self.file.create_entity(operation["value"]["type"], id=operation["value"]["id"])
                for k, v in operation["value"].items():
                    try:
                        setattr(e, k, self.unserialise_value(e, v))
                    except:
                        # Catch discrepancy where IfcOpenShell creates but doesn't allow editing of invalid values
                        pass
                for inverse_id, data in operation["inverses"].items():
                    inverse = self.file.by_id(inverse_id)
                    for index, value in data:
                        inverse[index] = self.unserialise_value(inverse, value)
            elif operation["action"] == "batch_delete":
                for inverse_id, data in operation["inverses"].items():
                    inverse = self.file.by_id(inverse_id)
                    for index, value in data:
                        inverse[index] = self.unserialise_value(inverse, value)

    def commit(self) -> None:
        for operation in self.operations:
            if operation["action"] == "create":
                e = self.file.create_entity(operation["value"]["type"], id=operation["value"]["id"])
                for k, v in operation["value"].items():
                    try:
                        setattr(e, k, self.unserialise_value(e, v))
                    except:
                        # Catch discrepancy where IfcOpenShell creates but doesn't allow editing of invalid values
                        pass
            elif operation["action"] == "edit":
                element = self.file.by_id(operation["id"])
                element[operation["index"]] = self.unserialise_value(element, operation["new"])
            elif operation["action"] == "delete":
                element = self.file.by_id(operation["value"]["id"])
                self.file.remove(element)
            elif operation["action"] == "batch_delete":
                pass


file_dict = {}

READ_ERROR = ifcopenshell_wrapper.file_open_status.READ_ERROR
NO_HEADER = ifcopenshell_wrapper.file_open_status.NO_HEADER
UNSUPPORTED_SCHEMA = ifcopenshell_wrapper.file_open_status.UNSUPPORTED_SCHEMA
INVALID_SYNTAX = ifcopenshell_wrapper.file_open_status.INVALID_SYNTAX


class file:
    """Base class for containing IFC files.

    Class has instance methods for filtering by element Id, Type, etc.
    Instantiated objects can be subscripted by Id or Guid

    Example:

    .. code:: python

        model = ifcopenshell.open(file_path)
        products = model.by_type("IfcProduct")
        print(products[0].id(), products[0].GlobalId) # 122 2XQ$n5SLP5MBLyL442paFx
        print(products[0] == model[122] == model["2XQ$n5SLP5MBLyL442paFx"]) # True
    """

    wrapped_data: ifcopenshell_wrapper.file
    history_size: int = 64

    def __init__(
        self,
        f: Optional[ifcopenshell_wrapper.file] = None,
        schema: Optional[str] = None,
        schema_version: Optional[tuple[int, int, int, int]] = None,
    ):
        """Create a new blank IFC model

        This IFC model does not have any entities in it yet. See the
        ``create_entity`` function for how to create new entities. All data is
        stored in memory. If you wish to write the IFC model to disk, see the
        ``write`` function.

        :param f: The underlying IfcOpenShell file object to be wrapped. This
            is an internal implementation detail and should generally be left
            as None by users.
        :param schema: Which IFC schema to use, chosen from "IFC2X3", "IFC4",
            or "IFC4X3". These refer to the ISO approved versions of IFC.
            Defaults to "IFC4" if not specified, which is currently recommended
            for all new projects.
        :type schema: string
        :param schema_version: If you want to specify an exact version of IFC
            that may not be an ISO approved version, use this argument instead
            of ``schema``. IFC versions on technical.buildingsmart.org are
            described using 4 integers representing the major, minor, addendum,
            and corrigendum number. For example, (4, 0, 2, 1) refers to IFC4
            ADD2 TC1, which is the official version approved by ISO when people
            refer to "IFC4". Generally you should not use this argument unless
            you are testing non-ISO IFC releases.
        :type schema_version: tuple[int, int, int, int]

        Example:

        .. code:: python

            # Create a new IFC4 model, create a wall, then save it to an IFC-SPF file.
            model = ifcopenshell.file()
            model.create_entity("IfcWall")
            model.write("/path/to/model.ifc")

            # Create a new IFC4X3 model
            model = ifcopenshell.file(schema="IFC4X3")

            # A poweruser testing out a particular version of IFC4X3
            model = ifcopenshell.file(schema_version=(4, 3, 0, 1))
        """
        if schema_version:
            prefixes = ("IFC", "X", "_ADD", "_TC")
            schema = "".join("".join(map(str, t)) if t[1] else "" for t in zip(prefixes, schema_version))
        else:
            schema = {"IFC4X3": "IFC4X3_ADD2"}.get(schema, schema)
        if f is not None:
            if not f.good():
                from . import Error, SchemaError

                exc, msg = {
                    READ_ERROR: (IOError, "Unable to open file for reading"),
                    NO_HEADER: (Error, "Unable to parse IFC SPF header"),
                    UNSUPPORTED_SCHEMA: (
                        SchemaError,
                        "Unsupported schema: %s" % ",".join(f.header.file_schema.schema_identifiers),
                    ),
                    INVALID_SYNTAX: (Error, "Syntax error during parse, check logs"),
                }[f.good().value()]
                raise exc(msg)
            self.wrapped_data = f
        else:
            args = filter(None, [schema])
            args = map(ifcopenshell_wrapper.schema_by_name, args)
            self.wrapped_data = ifcopenshell_wrapper.file(*args)
        self.history = []
        self.future = []
        self.transaction: Optional[Transaction] = None

        import weakref

        file_dict[self.file_pointer()] = weakref.ref(self)

    def __del__(self) -> None:
        # Avoid infinite recursion if file is failed to initialize
        # and wrapped_data is unset.
        if "wrapped_data" not in dir(self):
            return
        del file_dict[self.file_pointer()]

    def set_history_size(self, size: int) -> None:
        self.history_size = size
        while len(self.history) > self.history_size:
            self.history.pop(0)

    def begin_transaction(self) -> None:
        if self.history_size:
            self.transaction = Transaction(self)

    def end_transaction(self) -> None:
        if self.transaction:
            self.history.append(self.transaction)
            if len(self.history) > self.history_size:
                self.history.pop(0)
            self.future = []
            self.transaction = None

    def discard_transaction(self) -> None:
        if self.transaction:
            self.transaction.rollback()
        self.transaction = None

    def undo(self) -> None:
        if not self.history:
            return
        transaction = self.history.pop()
        transaction.rollback()
        self.future.append(transaction)

    def redo(self) -> None:
        if not self.future:
            return
        transaction = self.future.pop()
        transaction.commit()
        self.history.append(transaction)

    def create_entity(self, type: str, *args, **kwargs) -> ifcopenshell.entity_instance:
        """Create a new IFC entity in the file.

        You can also use dynamic methods similar to `ifc_file.createIfcWall(...)`
        to create IFC entities. They work exactly the same as if you would do
        `ifc_file.create_entity("IfcWall", ...)` but the resulting typing
        is not as accurate as for `create_entity` due to a dynamic nature
        of those methods.

        :param type: Case insensitive name of the IFC class
        :type type: string
        :param args: The positional arguments of the IFC class
        :param kwargs: The keyword arguments of the IFC class
        :returns: An entity instance
        :rtype: ifcopenshell.entity_instance

        Example:

        .. code:: python

            f = ifcopenshell.file()
            f.create_entity("IfcPerson")
            # >>> #1=IfcPerson($,$,$,$,$,$,$,$)
            f.create_entity("IfcPerson", "Foobar")
            # >>> #2=IfcPerson('Foobar',$,$,$,$,$,$,$)
            f.create_entity("IfcPerson", Identification="Foobar")
            # >>> #3=IfcPerson('Foobar',$,$,$,$,$,$,$)
        """
        eid = kwargs.pop("id", -1)

        e = entity_instance((self.schema_identifier, type), self)

        # Create pairs of {attribute index, attribute value}.
        # Keyword arguments are mapped to their corresponding
        # numeric index with get_argument_index().

        # @todo we should probably check that values for
        # attributes are not passed as duplicates using
        # both regular arguments and keyword arguments.
        kwargs_attrs = [(e.wrapped_data.get_argument_index(name), arg) for name, arg in kwargs.items()]
        attrs = list(enumerate(args)) + kwargs_attrs

        if len(attrs) > len(e):
            raise ValueError(
                "entity instance of type '%s' has only %s attributes but %s attributes were provided."
                % (e.is_a(True), len(e), len(attrs))
            )

        # Don't store these attributes as transactions
        # as the creation it self is already stored with
        # it's arguments
        if attrs:
            transaction = self.transaction
            self.transaction = None

        try:
            for idx, arg in attrs:
                e[idx] = arg
        except IndexError:
            invalid_attrs = []
            for (attr_index, _), attr_name in zip(kwargs_attrs, kwargs):
                if attr_index == 0xFFFFFFFF:
                    invalid_attrs.append(attr_name)
            raise ValueError(
                "entity instance of type '%s' doesn't have the following attributes: %s."
                % (e.is_a(True), ", ".join(invalid_attrs))
            )

        # Restore transaction status
        if attrs:
            self.transaction = transaction

        # Once the values are populated add the instance
        # to the file.
        self.wrapped_data.add(e.wrapped_data, eid)

        # The file container now handles the lifetime of
        # this instance. Tell SWIG that it is no longer
        # the owner.
        e.wrapped_data.this.disown()

        if self.transaction:
            self.transaction.store_create(e)

        return e

    @property
    def schema(self) -> ifcopenshell.util.schema.IFC_SCHEMA:
        """General IFC schema version: IFC2X3, IFC4, IFC4X3."""
        prefixes = ("IFC", "X", "_ADD", "_TC")
        reg = "".join(f"(?P<{s}>{s}\\d+)?" for s in prefixes)
        match = re.match(reg, self.wrapped_data.schema)
        version_tuple = tuple(
            map(
                lambda pp: int(pp[1][len(pp[0]) :]) if pp[1] else None,
                ((p, match.group(p)) for p in prefixes),
            )
        )
        return "".join("".join(map(str, t)) if t[1] else "" for t in zip(prefixes, version_tuple[0:2]))

    @property
    def schema_identifier(self) -> str:
        """Full IFC schema version: IFC2X3_TC1, IFC4_ADD2, IFC4X3_ADD2, etc."""
        return self.wrapped_data.schema

    @property
    def schema_version(self) -> tuple[int, int, int, int]:
        """Numeric representation of the full IFC schema version.

        E.g. IFC4X3_ADD2 is represented as (4, 3, 2, 0).
        """
        schema = self.wrapped_data.schema
        version = []
        for prefix in ("IFC", "X", "_ADD", "_TC"):
            number = re.search(prefix + r"(\d)", schema)
            version.append(int(number.group(1)) if number else 0)
        return tuple(version)

    def __getattr__(self, attr) -> Union[Any, Callable[..., ifcopenshell.entity_instance]]:
        if attr[0:6] == "create":
            return functools.partial(self.create_entity, attr[6:])
        else:
            return getattr(self.wrapped_data, attr)

    def __getitem__(self, key: Union[numbers.Integral, str, bytes]) -> entity_instance:
        if isinstance(key, numbers.Integral):
            return entity_instance(self.wrapped_data.by_id(key), self)
        elif isinstance(key, (str, bytes)):
            return entity_instance(self.wrapped_data.by_guid(str(key)), self)

    def by_id(self, id: int) -> ifcopenshell.entity_instance:
        """Return an IFC entity instance filtered by IFC ID.

        :param id: STEP numerical identifier
        :type id: int

        :raises RuntimeError: If `id` is not found.

        :returns: An ifcopenshell.entity_instance
        :rtype: ifcopenshell.entity_instance
        """
        return self[id]

    def by_guid(self, guid: str) -> ifcopenshell.entity_instance:
        """Return an IFC entity instance filtered by IFC GUID.

        :param guid: GlobalId value in 22-character encoded form
        :type guid: string

        :raises RuntimeError: If `guid` is not found.

        :returns: An ifcopenshell.entity_instance
        :rtype: ifcopenshell.entity_instance

        """
        return self[guid]

    def add(self, inst: ifcopenshell.entity_instance, _id: int = None) -> ifcopenshell.entity_instance:
        """Adds an entity including any dependent entities to an IFC file.
        If the entity already exists, it is not re-added. Existence of entity is checked by it's `.identity()`.

        :param inst: The entity instance to add
        :type inst: ifcopenshell.entity_instance
        :returns: An ifcopenshell.entity_instance
        :rtype: ifcopenshell.entity_instance
        """

        if self.transaction:
            max_id = self.wrapped_data.getMaxId()
        inst.wrapped_data.this.disown()
        result = entity_instance(self.wrapped_data.add(inst.wrapped_data, -1 if _id is None else _id), self)
        if self.transaction:
            added_elements = [e for e in self.traverse(result) if e.id() > max_id]
            [self.transaction.store_create(e) for e in reversed(added_elements)]
        return result

    def by_type(self, type: str, include_subtypes=True) -> list[ifcopenshell.entity_instance]:
        """Return IFC objects filtered by IFC Type and wrapped with the entity_instance class.

        If an IFC type class has subclasses, all entities of those subclasses are also returned.

        :param type: The case insensitive type of IFC class to return.
        :type type: string
        :param include_subtypes: Whether or not to return subtypes of the IFC class
        :type include_subtypes: bool

        :raises RuntimeError: If `type` is not found in IFC schema.

        :returns: A list of ifcopenshell.entity_instance objects
        :rtype: list[ifcopenshell.entity_instance]
        """
        if include_subtypes:
            return [entity_instance(e, self) for e in self.wrapped_data.by_type(type)]
        return [entity_instance(e, self) for e in self.wrapped_data.by_type_excl_subtypes(type)]

    def traverse(
        self, inst: ifcopenshell.entity_instance, max_levels: Optional[int] = None, breadth_first: bool = False
    ) -> list[ifcopenshell.entity_instance]:
        """Get a list of all referenced instances for a particular instance including itself

        :param inst: The entity instance to get all sub instances
        :param max_levels: How far deep to recursively fetch sub instances. None or -1 means infinite.
        :param breadth_first: Whether to use breadth-first search, the default is depth-first.
        :returns: A list of ifcopenshell.entity_instance objects
        """
        if max_levels is None:
            max_levels = -1

        if breadth_first:
            fn = self.wrapped_data.traverse_breadth_first
        else:
            fn = self.wrapped_data.traverse

        return [entity_instance(e, self) for e in fn(inst.wrapped_data, max_levels)]

    def get_inverse(
        self, inst: ifcopenshell.entity_instance, allow_duplicate: bool = False, with_attribute_indices: bool = False
    ) -> list[ifcopenshell.entity_instance]:
        """Return a list of entities that reference this entity

        Warning: this is a slow function, especially when there is a large
        number of inverses (such as for a shared owner history). If you are
        only interested in the total number of inverses (typically 0, 1, or N),
        consider using :func:`get_total_inverses`.

        :param inst: The entity instance to get inverse relationships
        :type inst: ifcopenshell.entity_instance
        :param allow_duplicate: Returns a `list` when True, `set` when False
        :param with_attribute_indices: Returns pairs of <i, idx>
           where i[idx] is inst or contains inst. Requires allow_duplicate=True
        :returns: A list of ifcopenshell.entity_instance objects
        :rtype: list[ifcopenshell.entity_instance]
        """
        if with_attribute_indices and not allow_duplicate:
            raise ValueError("with_attribute_indices requires allow_duplicate to be True")

        inverses = [entity_instance(e, self) for e in self.wrapped_data.get_inverse(inst.wrapped_data)]

        if allow_duplicate:
            if with_attribute_indices:
                idxs = self.wrapped_data.get_inverse_indices(inst.wrapped_data)
                return list(zip(inverses, idxs))
            else:
                return inverses

        return set(inverses)

    def get_total_inverses(self, inst: ifcopenshell.entity_instance) -> int:
        """Returns the number of entities that reference this entity

        This is equivalent to `len(model.get_inverse(element))`, but
        significantly faster.

        :param inst: The entity instance to get inverse relationships
        :type inst: ifcopenshell.entity_instance
        :returns: The total number of references
        :rtype: int
        """
        return self.wrapped_data.get_total_inverses(inst.wrapped_data)

    def remove(self, inst: ifcopenshell.entity_instance) -> None:
        """Deletes an IFC object in the file.

        Attribute values in other entity instances that reference the deleted
        object will be set to null. In the case of a list or set of references,
        the reference to the deleted will be removed from the aggregate.

        :param inst: The entity instance to delete
        :type inst: ifcopenshell.entity_instance
        :rtype: None
        """
        if self.transaction:
            self.transaction.store_delete(inst)
        return self.wrapped_data.remove(inst.wrapped_data)

    def batch(self):
        """Low-level mechanism to speed up deletion of large subgraphs"""
        if self.transaction:
            self.transaction.batch()
        return self.wrapped_data.batch()

    def unbatch(self):
        """Low-level mechanism to speed up deletion of large subgraphs"""
        if self.transaction:
            self.transaction.unbatch()
        return self.wrapped_data.unbatch()

    def __iter__(self) -> Generator[ifcopenshell.entity_instance, None, None]:
        return iter(self[id] for id in self.wrapped_data.entity_names())

    def assign_header_from(self, other):
        for k, vs in HEADER_FIELDS.items():
            for v in vs:
                setattr(getattr(self.header, k), v, getattr(getattr(other.header, k), v))

    def write(self, path: "os.PathLike | str", format: Optional[str] = None, zipped: bool = False) -> None:
        """Write ifc model to file.

        :param format: Force use of a specific format. Guessed from file name
            if None.  Supported formats : .ifc, .ifcXML, .ifcZIP (equivalent to
            format=".ifc" with zipped=True) For zipped .ifcXML use
            format=".ifcXML" with zipped=True
        :type format: str
        :param zipped: zip the file after it is written
        :type zipped: bool

        Example:

        .. code:: python

            model.write("path/to/model.ifc")
            model.write("path/to/model.ifcXML")
            model.write("path/to/model.ifcZIP")
            model.write("path/to/model.ifcZIP", format=".ifcXML", zipped=True)
            model.write("path/to/model.anyextension", format=".ifcXML")
        """
        path = Path(path)
        path.parent.mkdir(parents=True, exist_ok=True)
        if format == None:
            format = ifcopenshell.guess_format(path)
        if format == ".ifcXML":
            serializer = ifcopenshell_wrapper.XmlSerializer(self, str(path))
            serializer.finalize()
            if zipped:
                unzipped_path = path.with_suffix(format)
                path.rename(unzipped_path)
                with zipfile.ZipFile(path, "w") as zip_file:
                    zip_file.write(unzipped_path, unzipped_path.name, compress_type=zipfile.ZIP_DEFLATED)
                unzipped_path.unlink()
            return
        if format == ".ifcZIP":
            return self.write(path, ".ifc", zipped=True)
        self.wrapped_data.write(str(path))
        if zipped:
            unzipped_path = path.with_suffix(format)
            path.rename(unzipped_path)
            with zipfile.ZipFile(path, "w") as zip_file:
                zip_file.write(
                    unzipped_path,
                    unzipped_path.name,
                    compress_type=zipfile.ZIP_DEFLATED,
                )
                unzipped_path.unlink()
        return

    @staticmethod
    def from_string(s: str) -> "file":
        return file(ifcopenshell_wrapper.read(s))

    @staticmethod
    def from_pointer(v) -> "file":
        return file_dict.get(v)()

    def to_string(self) -> str:
        return self.wrapped_data.to_string()
