//! # RTX Segmentation
//!
//! Image segmentation and spatial mapping utilities for medical imaging.
//!
//! This crate provides tools for:
//! - K-D Tree spatial queries (nearest neighbor, k-nearest, radius search)
//! - K-means clustering for tissue segmentation
//! - Spatial mapping between point clouds and meshes
//!
//! ## Example
//!
//! ```rust,no_run
//! use rtx_segmentation::prelude::*;
//! use nalgebra::Point3;
//!
//! // Build a K-D tree from points
//! let points = vec![
//!     Point3::new(0.0, 0.0, 0.0),
//!     Point3::new(1.0, 0.0, 0.0),
//!     Point3::new(0.0, 1.0, 0.0),
//! ];
//! let tree = KdTree3D::build(&points);
//!
//! // Find nearest neighbor
//! let query = Point3::new(0.5, 0.5, 0.0);
//! let (index, distance) = tree.nearest(&query).unwrap();
//! ```

pub mod error;
pub mod kdtree;
pub mod kmeans;

pub use error::{Result, SegmentationError};

/// Prelude module with commonly used types.
pub mod prelude {
    pub use crate::error::{Result, SegmentationError};
    pub use crate::kdtree::{KdTree3D, bounding_box, center_of_mass};
    pub use crate::kmeans::{KMeans, KMeansConfig, KMeansResult, segment_volume_kmeans};
}

#[cfg(test)]
mod tests {
    use super::*;
    use nalgebra::Point3;

    #[test]
    fn test_prelude_imports() {
        use prelude::*;

        let points = vec![
            Point3::new(0.0, 0.0, 0.0),
            Point3::new(1.0, 0.0, 0.0),
            Point3::new(0.0, 1.0, 0.0),
        ];

        let tree = KdTree3D::build(&points);
        assert_eq!(tree.len(), 3);
    }

    #[test]
    fn test_integration() {
        use prelude::*;

        // Build tree
        let points = vec![
            Point3::new(0.0, 0.0, 0.0),
            Point3::new(1.0, 1.0, 1.0),
            Point3::new(2.0, 2.0, 2.0),
        ];
        let tree = KdTree3D::build(&points);

        // Test nearest
        let (idx, dist) = tree.nearest(&Point3::new(0.1, 0.1, 0.1)).unwrap();
        assert_eq!(idx, 0);
        assert!(dist < 0.2);

        // Test center of mass
        let com = center_of_mass(&points).unwrap();
        assert!((com - Point3::new(1.0, 1.0, 1.0)).norm() < 1e-10);

        // Test bounding box
        let (min, max) = bounding_box(&points).unwrap();
        assert!((min - Point3::new(0.0, 0.0, 0.0)).norm() < 1e-10);
        assert!((max - Point3::new(2.0, 2.0, 2.0)).norm() < 1e-10);
    }
}