u-nesting-d3 0.18.0

//! 3D geometry types.

use u_nesting_core::error::{check_above, check_at_least};
use u_nesting_core::geom::nalgebra_types::NaVector3 as Vector3;
use u_nesting_core::geometry::{Geometry, GeometryId, RotationConstraint};
use u_nesting_core::{Error, Result};

#[cfg(feature = "serde")]
use serde::{Deserialize, Serialize};

/// Orientation constraint for 3D placement.
#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
pub enum OrientationConstraint {
    /// Any orientation allowed (6 axis-aligned rotations for boxes).
    #[default]
    Any,
    /// Only upright orientations (2 rotations: original and 90° around Z).
    Upright,
    /// Fixed orientation (no rotation allowed).
    Fixed,
}

impl OrientationConstraint {
    /// The names [`OrientationConstraint::parse`] reads.
    pub const NAMES: [&'static str; 3] = ["any", "upright", "fixed"];

    /// Parses `"any"`, `"upright"` or `"fixed"` (case-insensitive); `None`
    /// for any other name, so a misspelling is refused rather than ignored.
    pub fn parse(name: &str) -> Option<Self> {
        match name.trim().to_lowercase().as_str() {
            "any" => Some(Self::Any),
            "upright" => Some(Self::Upright),
            "fixed" => Some(Self::Fixed),
            _ => None,
        }
    }
}

/// A 3D box geometry that can be packed.
#[derive(Debug, Clone)]
#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
pub struct Geometry3D {
    /// Unique identifier.
    id: GeometryId,

    /// Dimensions (width, depth, height).
    dimensions: Vector3<f64>,

    /// Number of copies to place.
    quantity: usize,

    /// Mass of the geometry (for weight constraints).
    mass: Option<f64>,

    /// Orientation constraint (for 3D-specific orientations).
    orientation: OrientationConstraint,

    /// Rotation constraint (for Geometry trait).
    rotation_constraint: RotationConstraint<f64>,

    /// Whether this item can have other items stacked on top.
    stackable: bool,

    /// Maximum weight that can be placed on top of this item.
    max_stack_weight: Option<f64>,
}

impl Geometry3D {
    /// Creates a new 3D box geometry with the given ID and dimensions.
    pub fn new(id: impl Into<GeometryId>, width: f64, depth: f64, height: f64) -> Self {
        Self {
            id: id.into(),
            dimensions: Vector3::new(width, depth, height),
            quantity: 1,
            mass: None,
            orientation: OrientationConstraint::default(),
            rotation_constraint: RotationConstraint::None,
            stackable: true,
            max_stack_weight: None,
        }
    }

    /// Alias for creating a box shape.
    pub fn box_shape(id: impl Into<GeometryId>, width: f64, depth: f64, height: f64) -> Self {
        Self::new(id, width, depth, height)
    }

    /// Sets the quantity to place.
    pub fn with_quantity(mut self, n: usize) -> Self {
        self.quantity = n;
        self
    }

    /// Sets the mass.
    pub fn with_mass(mut self, mass: f64) -> Self {
        self.mass = Some(mass);
        self
    }

    /// Sets the orientation constraint.
    pub fn with_orientation(mut self, constraint: OrientationConstraint) -> Self {
        self.orientation = constraint;
        self
    }

    /// Sets whether items can be stacked on top.
    pub fn with_stackable(mut self, stackable: bool) -> Self {
        self.stackable = stackable;
        self
    }

    /// Sets the maximum weight that can be stacked on top.
    pub fn with_max_stack_weight(mut self, weight: f64) -> Self {
        self.max_stack_weight = Some(weight);
        self
    }

    /// Returns the dimensions (width, depth, height).
    pub fn dimensions(&self) -> &Vector3<f64> {
        &self.dimensions
    }

    /// Returns the width.
    pub fn width(&self) -> f64 {
        self.dimensions.x
    }

    /// Returns the depth.
    pub fn depth(&self) -> f64 {
        self.dimensions.y
    }

    /// Returns the height.
    pub fn height(&self) -> f64 {
        self.dimensions.z
    }

    /// Returns the mass.
    pub fn mass(&self) -> Option<f64> {
        self.mass
    }

    /// Returns the orientation constraint.
    pub fn orientation_constraint(&self) -> OrientationConstraint {
        self.orientation
    }

    /// Returns whether items can be stacked on top.
    pub fn is_stackable(&self) -> bool {
        self.stackable
    }

    /// Returns the allowed orientations based on the constraint.
    /// Each orientation is (width_axis, depth_axis, height_axis).
    pub fn allowed_orientations(&self) -> Vec<(usize, usize, usize)> {
        match self.orientation {
            OrientationConstraint::Fixed => vec![(0, 1, 2)],
            OrientationConstraint::Upright => vec![(0, 1, 2), (1, 0, 2)],
            OrientationConstraint::Any => vec![
                (0, 1, 2), // Original
                (0, 2, 1), // Rotated 90° around X
                (1, 0, 2), // Rotated 90° around Z
                (1, 2, 0), // Rotated 90° around X then Z
                (2, 0, 1), // Rotated 90° around Y
                (2, 1, 0), // Rotated 90° around Y then X
            ],
        }
    }

    /// Returns the orientation label for a given orientation index, as an
    /// axis-permutation string (e.g. `"xyz"`, `"xzy"`).
    ///
    /// The permutation `(x_idx, y_idx, z_idx)` from [`allowed_orientations`]
    /// is mapped to the axis letters `x`/`y`/`z`. Out-of-range indices fall
    /// back to the identity orientation `"xyz"`.
    ///
    /// [`allowed_orientations`]: Self::allowed_orientations
    pub fn orientation_label(&self, orientation: usize) -> String {
        const AXES: [char; 3] = ['x', 'y', 'z'];
        let orientations = self.allowed_orientations();
        let (a, b, c) = orientations.get(orientation).copied().unwrap_or((0, 1, 2));
        [AXES[a], AXES[b], AXES[c]].iter().collect()
    }

    /// Returns dimensions for a given orientation index.
    pub fn dimensions_for_orientation(&self, orientation: usize) -> Vector3<f64> {
        let orientations = self.allowed_orientations();
        if orientation >= orientations.len() {
            return self.dimensions;
        }

        let (x_idx, y_idx, z_idx) = orientations[orientation];
        Vector3::new(
            self.dimensions[x_idx],
            self.dimensions[y_idx],
            self.dimensions[z_idx],
        )
    }
}

#[cfg(feature = "serde")]
impl Geometry3D {
    /// The geometry `request` describes, `index` being its position in the
    /// request's `geometries` -- the position a refusal names.
    ///
    /// # Errors
    ///
    /// `parameter_out_of_range` (with the id) for a quantity below 1, a
    /// negative one included (`geometries[index].quantity`), a dimension of 0
    /// or below (`geometries[index].dimensions[axis]`) or a negative mass
    /// (`geometries[index].mass`); `unknown_option`
    /// (`geometries[index].orientation`) for an orientation other than `any`,
    /// `upright` or `fixed`.
    pub fn from_request(
        index: usize,
        request: u_nesting_core::api_types::Geometry3DRequest,
    ) -> Result<Self> {
        let quantity = u_nesting_core::check_quantity(
            &format!("geometries[{index}].quantity"),
            &request.id,
            request.quantity,
        )?;
        let [width, depth, height] = request.dimensions;
        let mut geom = Self::new(request.id, width, depth, height).with_quantity(quantity);
        if let Some(mass) = request.mass {
            geom = geom.with_mass(mass);
        }
        if let Some(name) = request.orientation {
            let constraint =
                OrientationConstraint::parse(&name).ok_or_else(|| Error::UnknownOption {
                    parameter: format!("geometries[{index}].orientation"),
                    got: name.clone(),
                    expected: OrientationConstraint::NAMES.map(String::from).to_vec(),
                })?;
            geom = geom.with_orientation(constraint);
        }
        geom.check_measures(&format!("geometries[{index}]."))?;
        Ok(geom)
    }

    /// The geometries a request's `geometries` describe, in order; see
    /// [`Geometry3D::from_request`].
    ///
    /// # Errors
    ///
    /// The first geometry's refusal.
    pub fn from_requests(
        requests: Vec<u_nesting_core::api_types::Geometry3DRequest>,
    ) -> Result<Vec<Self>> {
        requests
            .into_iter()
            .enumerate()
            .map(|(index, request)| Self::from_request(index, request))
            .collect()
    }
}

impl Geometry for Geometry3D {
    type Scalar = f64;

    fn id(&self) -> &GeometryId {
        &self.id
    }

    fn quantity(&self) -> usize {
        self.quantity
    }

    fn measure(&self) -> f64 {
        self.dimensions.x * self.dimensions.y * self.dimensions.z
    }

    fn aabb_vec(&self) -> (Vec<f64>, Vec<f64>) {
        (
            vec![0.0, 0.0, 0.0],
            vec![self.dimensions.x, self.dimensions.y, self.dimensions.z],
        )
    }

    fn centroid(&self) -> Vec<f64> {
        vec![
            self.dimensions.x / 2.0,
            self.dimensions.y / 2.0,
            self.dimensions.z / 2.0,
        ]
    }

    fn rotation_constraint(&self) -> &RotationConstraint<f64> {
        &self.rotation_constraint
    }

    fn validate(&self) -> Result<()> {
        self.check_measures("")?;
        u_nesting_core::check_quantity("quantity", &self.id, self.quantity as i128)?;
        Ok(())
    }
}

impl Geometry3D {
    /// Each dimension (`dimensions[0]` width, `[1]` depth, `[2]` height) a
    /// finite number above 0 and a mass, when there is one, a finite number at
    /// least 0 -- or `parameter_out_of_range` naming the field after `at` and
    /// the geometry's id.
    fn check_measures(&self, at: &str) -> Result<()> {
        let of_this = |mut e: Error| {
            if let Error::OutOfRange { id, .. } = &mut e {
                *id = Some(self.id.clone());
            }
            e
        };
        for (axis, length) in self.dimensions.iter().enumerate() {
            check_above(&format!("{at}dimensions[{axis}]"), *length, 0.0).map_err(of_this)?;
        }
        if let Some(mass) = self.mass {
            check_at_least(&format!("{at}mass"), mass, 0.0).map_err(of_this)?;
        }
        Ok(())
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use approx::assert_relative_eq;

    #[test]
    fn test_box_volume() {
        let box3d = Geometry3D::new("B1", 10.0, 20.0, 30.0);
        assert_relative_eq!(box3d.measure(), 6000.0, epsilon = 0.001);
    }

    #[test]
    fn test_orientations() {
        let box3d = Geometry3D::new("B1", 10.0, 20.0, 30.0);

        // Any orientation should have 6 options
        assert_eq!(box3d.allowed_orientations().len(), 6);

        // Upright should have 2 options
        let upright = box3d
            .clone()
            .with_orientation(OrientationConstraint::Upright);
        assert_eq!(upright.allowed_orientations().len(), 2);

        // Fixed should have 1 option
        let fixed = box3d.clone().with_orientation(OrientationConstraint::Fixed);
        assert_eq!(fixed.allowed_orientations().len(), 1);
    }

    #[test]
    fn test_orientation_label() {
        // Default constraint is Any → 6 axis permutations map to labels.
        let geom = Geometry3D::new("B1", 10.0, 20.0, 30.0);
        assert_eq!(geom.orientation_label(0), "xyz");
        assert_eq!(geom.orientation_label(1), "xzy");
        assert_eq!(geom.orientation_label(2), "yxz");
        assert_eq!(geom.orientation_label(3), "yzx");
        assert_eq!(geom.orientation_label(4), "zxy");
        assert_eq!(geom.orientation_label(5), "zyx");
        // Out-of-range index falls back to identity orientation.
        assert_eq!(geom.orientation_label(99), "xyz");

        // Fixed constraint only ever yields the identity orientation.
        let fixed = geom.clone().with_orientation(OrientationConstraint::Fixed);
        assert_eq!(fixed.orientation_label(0), "xyz");
    }

    #[test]
    fn test_aabb() {
        use u_nesting_core::geometry::Geometry;
        let box3d = Geometry3D::new("B1", 10.0, 20.0, 30.0);
        let (min, max) = box3d.aabb_vec();

        assert_eq!(min, vec![0.0, 0.0, 0.0]);
        assert_eq!(max, vec![10.0, 20.0, 30.0]);
    }

    #[test]
    fn test_validation() {
        let valid = Geometry3D::new("B1", 10.0, 20.0, 30.0);
        assert!(valid.validate().is_ok());

        let invalid = Geometry3D::new("B2", -10.0, 20.0, 30.0);
        assert!(invalid.validate().is_err());

        let zero_qty = Geometry3D::new("B3", 10.0, 20.0, 30.0).with_quantity(0);
        assert!(zero_qty.validate().is_err());
    }

    /// A dimension of 0 or below and a negative mass are values out of their
    /// range, naming the field and the geometry.
    #[test]
    fn a_dimension_or_mass_out_of_range_names_the_field() {
        let refused = |geometry: Geometry3D| match geometry.validate() {
            Err(Error::OutOfRange {
                parameter,
                id,
                min,
                exclusive_min,
                got,
                ..
            }) => (parameter, id, min, exclusive_min, got),
            other => panic!("{other:?}"),
        };
        assert_eq!(
            refused(Geometry3D::new("crate", 10.0, 0.0, 30.0)),
            (
                "dimensions[1]".to_string(),
                Some("crate".to_string()),
                None,
                Some(0.0),
                0.0
            )
        );
        assert_eq!(
            refused(Geometry3D::new("crate", 10.0, 20.0, 30.0).with_mass(-1.0)),
            (
                "mass".to_string(),
                Some("crate".to_string()),
                Some(0.0),
                None,
                -1.0
            )
        );
        assert!(Geometry3D::new("crate", 1.0, 1.0, 1.0)
            .with_mass(0.0)
            .validate()
            .is_ok());
    }
}