Skip to main content

ifc_spatial/tree/
kind.rs

1//! Where an entity sits in the spatial hierarchy.
2//!
3//! # From the declared release, not from the name
4//!
5//! A spatial container is an `IfcSpatialElement` (IFC4 ADD2 TC1, IFC4X3
6//! ADD2) or an `IfcSpatialStructureElement` (IFC2X3 TC1, which has no
7//! `IfcSpatialElement`), plus the `IfcProject` at the root. The set differs
8//! by release: IFC4 adds `IfcSpatialZone` and `IfcExternalSpatialElement`,
9//! IFC4X3 adds `IfcFacility` with `IfcBridge`, `IfcRoad`, `IfcRailway` and
10//! `IfcMarineFacility`, and the `IfcFacilityPart` subtypes. None of those
11//! names shares a pattern, so membership is the release's own subtype test
12//! (`Schema::is_a`) against the bundled table of the release the file
13//! declares.
14
15use ifc_model::Model;
16use ifc_schema::{for_version, Schema, SchemaVersion};
17
18/// The spatial role of an entity, as far as containment is concerned.
19///
20/// The five named kinds are those exact entities. Every other spatial
21/// element of the release is [`OtherContainer`](Self::OtherContainer).
22#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
23#[non_exhaustive]
24pub enum SpatialKind {
25    /// `IfcProject` -- the root. A conformant file has exactly one.
26    Project,
27    /// `IfcSite`.
28    Site,
29    /// `IfcBuilding`.
30    Building,
31    /// `IfcBuildingStorey`.
32    Storey,
33    /// `IfcSpace`.
34    Space,
35    /// Any other spatial element of the release: `IfcSpatialZone` and
36    /// `IfcExternalSpatialElement` (IFC4, IFC4X3), and the IFC4X3
37    /// facilities (`IfcFacility`, `IfcBridge`, `IfcRoad`, `IfcRailway`,
38    /// `IfcMarineFacility`) and facility parts (`IfcBridgePart`,
39    /// `IfcRoadPart`, `IfcRailwayPart`, `IfcMarinePart`,
40    /// `IfcFacilityPartCommon`).
41    OtherContainer,
42    /// Not a spatial container: a wall, a door, a slab, or any entity the
43    /// release does not declare as a spatial element.
44    Element,
45}
46
47impl SpatialKind {
48    /// Classify a STEP type name without a release: a container when any
49    /// bundled release (IFC2X3, IFC4, IFC4X3) declares it a spatial
50    /// element.
51    ///
52    /// No bundled release declares as a spatial element a name another
53    /// declares as something else (`tests/classification.rs` asserts it),
54    /// so this never contradicts [`classify_in`](Self::classify_in) for a
55    /// name the release declares. Prefer `classify_in` when the release is
56    /// known; [`SpatialTree`](crate::SpatialTree) does.
57    #[must_use]
58    pub fn classify(type_name: &str) -> Self {
59        Classifier::any_release().classify(type_name)
60    }
61
62    /// Classify a STEP type name against one release's schema table.
63    #[must_use]
64    pub fn classify_in(type_name: &str, release: SchemaVersion) -> Self {
65        Classifier::for_release(release).classify(type_name)
66    }
67
68    /// Whether entities of this kind can contain others.
69    #[must_use]
70    pub const fn is_container(self) -> bool {
71        !matches!(self, Self::Element)
72    }
73}
74
75/// Releases the spatial classification is verified against.
76const VERIFIED: [SchemaVersion; 3] = [
77    SchemaVersion::Ifc2x3,
78    SchemaVersion::Ifc4,
79    SchemaVersion::Ifc4x3,
80];
81
82/// The table(s) a classification is answered from.
83pub(crate) struct Classifier {
84    /// The bound release, if the file declares exactly one bundled release.
85    release: Option<SchemaVersion>,
86    tables: Vec<&'static Schema>,
87}
88
89impl Classifier {
90    /// The release `model` declares, when it names exactly one release this
91    /// classifier is verified for; otherwise every verified release, with
92    /// none bound.
93    ///
94    /// IFC4X1 and IFC4X2 are bundled by `ifc-schema` but not verified here,
95    /// so they bind nothing ([`Self::bound_release`] is `None`) rather than
96    /// being read as IFC4 or IFC4X3.
97    pub(crate) fn for_model(model: &Model) -> Self {
98        match model.header().schema.as_slice() {
99            [token] => match SchemaVersion::from_header_token(token) {
100                Some(release) if VERIFIED.contains(&release) => Self::for_release(release),
101                _ => Self::any_release(),
102            },
103            _ => Self::any_release(),
104        }
105    }
106
107    fn for_release(release: SchemaVersion) -> Self {
108        Self {
109            release: Some(release),
110            tables: for_version(release).into_iter().collect(),
111        }
112    }
113
114    fn any_release() -> Self {
115        let tables = VERIFIED
116            .into_iter()
117            .filter_map(|release| for_version(release).ok())
118            .collect();
119        Self {
120            release: None,
121            tables,
122        }
123    }
124
125    /// The release bound, or `None` when every bundled release is asked.
126    pub(crate) fn bound_release(&self) -> Option<SchemaVersion> {
127        self.release
128    }
129
130    pub(crate) fn classify(&self, type_name: &str) -> SpatialKind {
131        let upper = type_name.to_ascii_uppercase();
132        if !self.tables.iter().any(|table| is_spatial(table, &upper)) {
133            return SpatialKind::Element;
134        }
135        match upper.as_str() {
136            "IFCPROJECT" => SpatialKind::Project,
137            "IFCSITE" => SpatialKind::Site,
138            "IFCBUILDING" => SpatialKind::Building,
139            "IFCBUILDINGSTOREY" => SpatialKind::Storey,
140            "IFCSPACE" => SpatialKind::Space,
141            _ => SpatialKind::OtherContainer,
142        }
143    }
144}
145
146/// Whether `table` declares `upper` as the project or a spatial element.
147fn is_spatial(table: &Schema, upper: &str) -> bool {
148    // IfcProject is an IfcContext (IFC4, IFC4X3) or an IfcObject (IFC2X3),
149    // not a spatial element, but it is the root every tree hangs from.
150    if upper == "IFCPROJECT" {
151        return table.is_a(upper, "IFCPROJECT");
152    }
153    // IFC2X3 has no IfcSpatialElement; its spatial root is
154    // IfcSpatialStructureElement. Asking for an undeclared ancestor
155    // answers false, so the IFC4 root is tried first and the IFC2X3 one
156    // only matters where it is the root.
157    table.is_a(upper, "IFCSPATIALELEMENT") || table.is_a(upper, "IFCSPATIALSTRUCTUREELEMENT")
158}
159
160#[cfg(test)]
161mod intermediate_release_tests {
162    use super::*;
163
164    /// An IFC4X1 or IFC4X2 header binds no release: the classifier answers
165    /// from the verified tables with nothing bound, instead of claiming the
166    /// file was read as IFC4 or IFC4X3.
167    #[test]
168    fn ifc4x1_and_ifc4x2_bind_no_release() {
169        for token in ["IFC4X1", "IFC4X2"] {
170            let mut model = Model::new();
171            model.header_mut().schema = vec![token.to_owned()];
172            assert_eq!(
173                Classifier::for_model(&model).bound_release(),
174                None,
175                "{token}"
176            );
177        }
178        let mut model = Model::new();
179        model.header_mut().schema = vec!["IFC4X3".to_owned()];
180        assert_eq!(
181            Classifier::for_model(&model).bound_release(),
182            Some(SchemaVersion::Ifc4x3)
183        );
184    }
185}