gerber_viewer 0.4.2

use std::f64::consts::PI;

#[cfg(feature = "egui")]
use egui::{Pos2, Vec2};
use gerber_types::{AxisSelect, ImageMirroring};
use nalgebra::{Matrix3, Point2, Vector2, Vector3};

use crate::geometry::mirroring::Mirroring;

/// Gerber-specific transform.
/// Transform order: -Origin, Mirroring, Rotation, *Scale, +Origin, +Offset
///
/// * Origin is subtracted from coordinates so that rotation and mirroring occur around the origin.
/// * After mirroring, rotation and scaling, Origin is then added to relocate the coordinates
/// * Finally, an offset is added
#[derive(Debug, Copy, Clone)]
pub struct GerberTransform {
    /// rotation in radians, positive = counter-clockwise
    pub rotation: f32,
    pub mirroring: Mirroring,
    // origin for rotation and mirroring, in gerber coordinates
    pub origin: Vector2<f64>,
    // offset, in gerber coordinates
    pub offset: Vector2<f64>,
    // scale factor, 0.5 = 50%, 1.0 = 100%
    pub scale: f64,
}

impl Default for GerberTransform {
    fn default() -> Self {
        Self {
            rotation: 0.0,
            mirroring: Mirroring::default(),
            origin: Vector2::new(0.0, 0.0),
            offset: Vector2::new(0.0, 0.0),
            scale: 1.0,
        }
    }
}

impl GerberTransform {
    /// Apply the transform to a logical `Point2` (Gerber-space)
    #[inline]
    pub fn apply_to_position(&self, pos: Point2<f64>) -> Point2<f64> {
        // Adjust for origin
        let pos_adjusted = (pos.x - self.origin.x, pos.y - self.origin.y);

        // Apply mirroring
        let (mirrored_x, mirrored_y) = self.mirroring * pos_adjusted;

        // Apply rotation (using f64 for calculations)
        let rotation = self.rotation as f64;
        let cos_angle = rotation.cos();
        let sin_angle = rotation.sin();

        let rotated_x = mirrored_x * cos_angle - mirrored_y * sin_angle;
        let rotated_y = mirrored_x * sin_angle + mirrored_y * cos_angle;

        // Apply scale and offset
        Point2::new(
            rotated_x * self.scale + self.offset.x + self.origin.x,
            rotated_y * self.scale + self.offset.y + self.origin.y,
        )
    }

    /// Apply transform to a Vec2 instead of Point2 (used for bbox drawing)
    #[cfg(feature = "egui")]
    #[inline]
    pub fn apply_to_pos2(&self, pos: Pos2) -> Vec2 {
        // Adjust for origin
        let pos_adjusted = (pos.x as f64 - self.origin.x, pos.y as f64 - self.origin.y);

        // Apply mirroring
        let (mirrored_x, mirrored_y) = self.mirroring * pos_adjusted;

        // Apply rotation (using f64 for calculations)
        // Pos 2 are in SCREEN coordinates, Positive Y = DOWN so we need to invert the rotation
        let (sin_theta, cos_theta) = (-self.rotation as f64).sin_cos();
        let rotated_x = mirrored_x * cos_theta - mirrored_y * sin_theta;
        let rotated_y = mirrored_x * sin_theta + mirrored_y * cos_theta;

        // Apply scale and offset
        Vec2::new(
            (rotated_x * self.scale + self.origin.x + self.offset.x) as f32,
            (rotated_y * self.scale + self.origin.y + self.offset.y) as f32,
        )
    }

    pub fn flip_y(mut self) -> Self {
        self.offset.y = -self.offset.y;
        self.origin.y = -self.origin.y;

        self
    }
}

impl GerberTransform {
    /// Converts this transform to a 3x3 homogeneous transformation matrix
    pub fn to_matrix(&self) -> Matrix3<f64> {
        // Originally AI generated by Claude 3.7 Sonnet

        // Step 1: Translate by -origin
        let translate_neg_origin = Matrix3::new(1.0, 0.0, -self.origin.x, 0.0, 1.0, -self.origin.y, 0.0, 0.0, 1.0);

        // Step 2: Apply rotation
        let rad = self.rotation as f64;
        let cos_rad = rad.cos();
        let sin_rad = rad.sin();
        let rotation_matrix = Matrix3::new(cos_rad, -sin_rad, 0.0, sin_rad, cos_rad, 0.0, 0.0, 0.0, 1.0);

        // Step 3: Apply mirroring (if any)
        let [mirror_x, mirror_y] = self.mirroring.as_f64();
        let mirroring_matrix = Matrix3::new(mirror_x, 0.0, 0.0, 0.0, mirror_y, 0.0, 0.0, 0.0, 1.0);

        // Step 4: Apply scaling
        let scaling_matrix = Matrix3::new(self.scale, 0.0, 0.0, 0.0, self.scale, 0.0, 0.0, 0.0, 1.0);

        // Step 5: Translate back by origin
        let translate_origin = Matrix3::new(1.0, 0.0, self.origin.x, 0.0, 1.0, self.origin.y, 0.0, 0.0, 1.0);

        // Step 6: Apply offset
        let translate_offset = Matrix3::new(1.0, 0.0, self.offset.x, 0.0, 1.0, self.offset.y, 0.0, 0.0, 1.0);

        // Combine all matrices: translate_offset * translate_origin * scaling * rotation * mirroring * translate_neg_origin
        translate_offset * translate_origin * scaling_matrix * rotation_matrix * mirroring_matrix * translate_neg_origin
    }

    /// Creates a combined transform by multiplying the matrices of two transforms
    pub fn combine(&self, other: &GerberTransform) -> Self {
        // Originally AI generated by Clause 3.7 Sonnet

        // Get the matrices for both transforms
        let matrix1 = self.to_matrix();
        let matrix2 = other.to_matrix();

        // Multiply the matrices (order matters: self is applied first, then other)
        let combined_matrix = matrix2 * matrix1;

        // Extract transform parameters from the combined matrix
        Self::from_matrix(&combined_matrix)
    }

    /// Extract transform parameters from a matrix
    pub fn from_matrix(matrix: &Matrix3<f64>) -> Self {
        // Originally AI generated by Clause 3.7 Sonnet

        // Extract translation components (offset)
        let offset = Vector2::new(matrix[(0, 2)], matrix[(1, 2)]);

        // Extract the 2x2 transformation part
        let a = matrix[(0, 0)];
        let b = matrix[(0, 1)];
        let c = matrix[(1, 0)];
        let d = matrix[(1, 1)];

        // Determine if there's mirroring by checking the determinant
        let det = a * d - b * c;
        let mirroring_x = det < 0.0;
        let mirroring_y = false; // We'll only use x-mirroring for simplicity

        // Calculate scale (average of scaling in x and y directions)
        let scale_x = (a * a + c * c).sqrt();
        let scale_y = (b * b + d * d).sqrt();
        let scale = (scale_x + scale_y) / 2.0;

        // Calculate rotation
        // If det < 0, we have mirroring, so adjust the calculation
        let rotation_radians = if !mirroring_x { c.atan2(a) } else { (-c).atan2(-a) } as f32;

        // Use (0,0) as the origin for the combined transform
        // This is because we've already incorporated the original origins
        // into the combined matrix
        Self {
            rotation: rotation_radians,
            mirroring: Mirroring {
                x: mirroring_x,
                y: mirroring_y,
            },
            origin: Vector2::new(0.0, 0.0),
            offset,
            scale,
        }
    }

    /// Applies this transform to a position
    pub fn apply_to_position_matrix(&self, position: Point2<f64>) -> Point2<f64> {
        // Originally AI generated by Clause 3.7 Sonnet

        // Convert to homogeneous coordinates
        let point_vec = Vector3::new(position.x, position.y, 1.0);

        // Apply the transformation matrix
        let matrix = self.to_matrix();
        let transformed = matrix * point_vec;

        // Convert back from homogeneous coordinates
        Point2::new(transformed[0], transformed[1])
    }

    /// Apply transform to a Pos2 instead of Point2 (used for bbox drawing)
    #[cfg(feature = "egui")]
    pub fn apply_to_pos2_matrix(&self, pos: Pos2) -> Vec2 {
        // Originally AI generated by Clause 3.7 Sonnet

        // Convert from Pos2 (screen coords) to our matrix coordinate system
        // Note: Screen coordinates have positive Y pointing DOWN, so we need to adjust the rotation

        // Create a transform that has the rotation direction inverted
        let mut screen_transform = self.clone();
        screen_transform.rotation = -self.rotation;

        // Get the transformation matrix
        let matrix = screen_transform.to_matrix();

        // Convert Pos2 to homogeneous coordinates
        let point_vec = nalgebra::Vector3::new(pos.x as f64, pos.y as f64, 1.0);

        // Apply the transformation matrix
        let transformed = matrix * point_vec;

        // Convert back to Vec2
        Vec2::new(transformed[0] as f32, transformed[1] as f32)
    }
}

/// Extension trait for transforming Point2<f64> using a Matrix3<f64>
pub trait Matrix3Point2Ext {
    /// Apply this matrix transformation to a Point2<f64>
    fn transform_point2(&self, point: Point2<f64>) -> Point2<f64>;
}

impl Matrix3Point2Ext for Matrix3<f64> {
    #[inline]
    fn transform_point2(&self, point: Point2<f64>) -> Point2<f64> {
        // Convert to homogeneous coordinates
        let point_vec = Vector3::new(point.x, point.y, 1.0);

        // Apply the transformation matrix
        let transformed = self * point_vec;

        // Convert back from homogeneous coordinates
        Point2::new(transformed[0], transformed[1])
    }
}

/// Extension trait for transforming egui's Pos2 using a Matrix3<f64>
#[cfg(feature = "egui")]
pub trait Matrix3Pos2Ext {
    /// Apply this matrix transformation to a Pos2 (screen coordinates)
    /// Handles the Y-axis difference between mathematical and screen coordinates
    fn transform_pos2(&self, pos: Pos2) -> Vec2;
}

#[cfg(feature = "egui")]
impl Matrix3Pos2Ext for Matrix3<f64> {
    #[inline]
    fn transform_pos2(&self, pos: Pos2) -> Vec2 {
        // Convert Pos2 to homogeneous coordinates, flipping Y to match mathematical coordinates
        let point_vec = Vector3::new(pos.x as f64, -(pos.y as f64), 1.0);

        // Apply the transformation matrix
        let transformed = self * point_vec;

        // Convert back to Vec2, flipping Y back to screen coordinates
        Vec2::new(transformed[0] as f32, -transformed[1] as f32)
    }
}

#[cfg(test)]
mod transform_tests {
    // All tests AI generated by Clause 3.7 Sonnet

    use std::f32::consts::PI;

    use nalgebra::{Point2, Vector2};

    use crate::geometry::mirroring::Mirroring;
    use crate::geometry::*;

    #[test]
    fn test_identity_transform_matrix() {
        let identity = GerberTransform {
            rotation: 0.0,
            mirroring: Mirroring::default(),
            origin: Vector2::new(0.0, 0.0),
            offset: Vector2::new(0.0, 0.0),
            scale: 1.0,
        };

        let matrix = identity.to_matrix();
        // Identity matrix should be close to:
        // [1 0 0]
        // [0 1 0]
        // [0 0 1]
        assert!((matrix[(0, 0)] - 1.0).abs() < 1e-6);
        assert!((matrix[(0, 1)] - 0.0).abs() < 1e-6);
        assert!((matrix[(0, 2)] - 0.0).abs() < 1e-6);
        assert!((matrix[(1, 0)] - 0.0).abs() < 1e-6);
        assert!((matrix[(1, 1)] - 1.0).abs() < 1e-6);
        assert!((matrix[(1, 2)] - 0.0).abs() < 1e-6);
        assert!((matrix[(2, 0)] - 0.0).abs() < 1e-6);
        assert!((matrix[(2, 1)] - 0.0).abs() < 1e-6);
        assert!((matrix[(2, 2)] - 1.0).abs() < 1e-6);

        // Converting back should give us the same transform
        let reconstructed = GerberTransform::from_matrix(&matrix);
        assert!((reconstructed.rotation - 0.0).abs() < 1e-6);
        assert_eq!(reconstructed.mirroring.x, false);
        assert_eq!(reconstructed.mirroring.y, false);
        assert!((reconstructed.origin.x - 0.0).abs() < 1e-6);
        assert!((reconstructed.origin.y - 0.0).abs() < 1e-6);
        assert!((reconstructed.offset.x - 0.0).abs() < 1e-6);
        assert!((reconstructed.offset.y - 0.0).abs() < 1e-6);
        assert!((reconstructed.scale - 1.0).abs() < 1e-6);
    }

    #[test]
    fn test_rotation_transform_matrix() {
        let rotation_90 = GerberTransform {
            rotation: PI / 2.0, // 90 degrees
            mirroring: Mirroring::default(),
            origin: Vector2::new(0.0, 0.0),
            offset: Vector2::new(0.0, 0.0),
            scale: 1.0,
        };

        let matrix = rotation_90.to_matrix();
        // 90 degree rotation matrix should be close to:
        // [0 -1 0]
        // [1  0 0]
        // [0  0 1]
        assert!((matrix[(0, 0)] - 0.0).abs() < 1e-6);
        assert!((matrix[(0, 1)] - -1.0).abs() < 1e-6);
        assert!((matrix[(0, 2)] - 0.0).abs() < 1e-6);
        assert!((matrix[(1, 0)] - 1.0).abs() < 1e-6);
        assert!((matrix[(1, 1)] - 0.0).abs() < 1e-6);
        assert!((matrix[(1, 2)] - 0.0).abs() < 1e-6);

        // Converting back should give us the same transform
        let reconstructed = GerberTransform::from_matrix(&matrix);
        assert!((reconstructed.rotation - PI / 2.0).abs() < 1e-6);
        assert_eq!(reconstructed.mirroring.x, false);
        assert!((reconstructed.scale - 1.0).abs() < 1e-6);
    }

    #[test]
    fn test_offset_transform_matrix() {
        let offset_transform = GerberTransform {
            rotation: 0.0,
            mirroring: Mirroring::default(),
            origin: Vector2::new(0.0, 0.0),
            offset: Vector2::new(10.0, 20.0),
            scale: 1.0,
        };

        let matrix = offset_transform.to_matrix();
        // Translation matrix should be close to:
        // [1 0 10]
        // [0 1 20]
        // [0 0  1]
        assert!((matrix[(0, 0)] - 1.0).abs() < 1e-6);
        assert!((matrix[(0, 1)] - 0.0).abs() < 1e-6);
        assert!((matrix[(0, 2)] - 10.0).abs() < 1e-6);
        assert!((matrix[(1, 0)] - 0.0).abs() < 1e-6);
        assert!((matrix[(1, 1)] - 1.0).abs() < 1e-6);
        assert!((matrix[(1, 2)] - 20.0).abs() < 1e-6);

        // Converting back should give us the same transform
        let reconstructed = GerberTransform::from_matrix(&matrix);
        assert!((reconstructed.rotation - 0.0).abs() < 1e-6);
        assert_eq!(reconstructed.mirroring.x, false);
        assert!((reconstructed.offset.x - 10.0).abs() < 1e-6);
        assert!((reconstructed.offset.y - 20.0).abs() < 1e-6);
        assert!((reconstructed.scale - 1.0).abs() < 1e-6);
    }

    #[test]
    fn test_combined_transforms_example() {
        // Box 1 at (-5, 0)
        let box1_position = Point2::new(-5.0, 0.0);

        // Box 2 at (5, 0)
        let box2_position = Point2::new(5.0, 0.0);

        // Step 1: Create individual 45-degree rotation transforms for each box
        let transform1 = GerberTransform {
            rotation: PI / 4.0, // 45 degrees
            mirroring: Mirroring::default(),
            origin: Vector2::new(-5.0, 0.0), // Rotate around box1's position
            offset: Vector2::new(0.0, 0.0),
            scale: 1.0,
        };

        let transform2 = GerberTransform {
            rotation: PI / 4.0, // 45 degrees
            mirroring: Mirroring::default(),
            origin: Vector2::new(5.0, 0.0), // Rotate around box2's position
            offset: Vector2::new(0.0, 0.0),
            scale: 1.0,
        };

        // Step 2: Create a 90-degree rotation transform around (0, 0) for both boxes
        let transform_both = GerberTransform {
            rotation: PI / 2.0, // 90 degrees
            mirroring: Mirroring::default(),
            origin: Vector2::new(0.0, 0.0), // Rotate around the origin
            offset: Vector2::new(0.0, 0.0),
            scale: 1.0,
        };

        // Apply transforms to get reference results
        let box1_transform1 = transform1.apply_to_position_matrix(box1_position);
        println!("box1_transform1: {:?}", [box1_transform1.x, box1_transform1.y]);

        let box2_transform2 = transform2.apply_to_position_matrix(box2_position);
        println!("box2_transform2: {:?}", [box2_transform2.x, box2_transform2.y]);

        let box1_final_reference = transform_both.apply_to_position_matrix(box1_transform1);
        println!("box1_final_reference: {:?}", [
            box1_final_reference.x,
            box1_final_reference.y
        ]);

        let box2_final_reference = transform_both.apply_to_position_matrix(box2_transform2);
        println!("box2_final_reference: {:?}", [
            box2_final_reference.x,
            box2_final_reference.y
        ]);

        // Create combined transforms using the new matrix-based approach
        let combined1_matrix = transform1.combine(&transform_both);
        let combined2_matrix = transform2.combine(&transform_both);

        // Apply the combined transforms
        let box1_final_matrix = combined1_matrix.apply_to_position_matrix(box1_position);
        println!("box1_final_matrix: {:?}", [box1_final_matrix.x, box1_final_matrix.y]);

        let box2_final_matrix = combined2_matrix.apply_to_position_matrix(box2_position);
        println!("box2_final_matrix: {:?}", [box2_final_matrix.x, box2_final_matrix.y]);

        // Print the combined transforms for debugging
        println!(
            "combined1_matrix: rotation={}, offset={:?}, origin={:?}, scale={}",
            combined1_matrix.rotation,
            [combined1_matrix.offset.x, combined1_matrix.offset.y],
            [combined1_matrix.origin.x, combined1_matrix.origin.y],
            combined1_matrix.scale
        );

        println!(
            "combined2_matrix: rotation={}, offset={:?}, origin={:?}, scale={}",
            combined2_matrix.rotation,
            [combined2_matrix.offset.x, combined2_matrix.offset.y],
            [combined2_matrix.origin.x, combined2_matrix.origin.y],
            combined2_matrix.scale
        );

        // Verify that matrix-combined transforms produce correct results
        assert!((box1_final_matrix.x - box1_final_reference.x).abs() < 1e-6);
        assert!((box1_final_matrix.y - box1_final_reference.y).abs() < 1e-6);

        assert!((box2_final_matrix.x - box2_final_reference.x).abs() < 1e-6);
        assert!((box2_final_matrix.y - box2_final_reference.y).abs() < 1e-6);
    }

    #[test]
    fn test_two_boxes_with_rotation() {
        // Box positions
        let box1_position = Point2::new(-5.0, -5.0);
        let box2_position = Point2::new(-5.0, 5.0);

        // Step 1: Create individual 45-degree rotation transforms for each box
        let transform1 = GerberTransform {
            rotation: PI / 4.0, // 45 degrees
            mirroring: Mirroring::default(),
            origin: Vector2::new(-5.0, -5.0), // Rotate around box1's position
            offset: Vector2::new(0.0, 0.0),
            scale: 1.0,
        };

        let transform2 = GerberTransform {
            rotation: PI / 4.0, // 45 degrees
            mirroring: Mirroring::default(),
            origin: Vector2::new(-5.0, 5.0), // Rotate around box2's position
            offset: Vector2::new(0.0, 0.0),
            scale: 1.0,
        };

        // Step 2: Create a 90-degree rotation transform around (0, 0) for both boxes
        let transform_both = GerberTransform {
            rotation: PI / 2.0, // 90 degrees
            mirroring: Mirroring::default(),
            origin: Vector2::new(0.0, 0.0), // Rotate around the origin
            offset: Vector2::new(0.0, 0.0),
            scale: 1.0,
        };

        // Apply transforms sequentially to get reference results
        let box1_after_local = transform1.apply_to_position_matrix(box1_position);
        println!(
            "Box1 after local rotation: ({:.2}, {:.2})",
            box1_after_local.x, box1_after_local.y
        );

        let box2_after_local = transform2.apply_to_position_matrix(box2_position);
        println!(
            "Box2 after local rotation: ({:.2}, {:.2})",
            box2_after_local.x, box2_after_local.y
        );

        let box1_final_reference = transform_both.apply_to_position_matrix(box1_after_local);
        println!(
            "Box1 final position (sequential): ({:.2}, {:.2})",
            box1_final_reference.x, box1_final_reference.y
        );

        let box2_final_reference = transform_both.apply_to_position_matrix(box2_after_local);
        println!(
            "Box2 final position (sequential): ({:.2}, {:.2})",
            box2_final_reference.x, box2_final_reference.y
        );

        // Create combined transforms using matrix-based approach
        let combined1 = transform1.combine(&transform_both);
        let combined2 = transform2.combine(&transform_both);

        // Apply the combined transforms
        let box1_final_combined = combined1.apply_to_position_matrix(box1_position);
        println!(
            "Box1 final position (combined): ({:.2}, {:.2})",
            box1_final_combined.x, box1_final_combined.y
        );

        let box2_final_combined = combined2.apply_to_position_matrix(box2_position);
        println!(
            "Box2 final position (combined): ({:.2}, {:.2})",
            box2_final_combined.x, box2_final_combined.y
        );

        // Print the combined transforms for debugging
        println!(
            "Combined transform for Box1: rotation={:.2} degrees, offset=({:.2}, {:.2}), origin=({:.2}, {:.2}), scale={:.2}",
            combined1.rotation * 180.0 / PI as f32,
            combined1.offset.x,
            combined1.offset.y,
            combined1.origin.x,
            combined1.origin.y,
            combined1.scale
        );

        println!(
            "Combined transform for Box2: rotation={:.2} degrees, offset=({:.2}, {:.2}), origin=({:.2}, {:.2}), scale={:.2}",
            combined2.rotation * 180.0 / PI as f32,
            combined2.offset.x,
            combined2.offset.y,
            combined2.origin.x,
            combined2.origin.y,
            combined2.scale
        );

        // Verify that the boxes end up at the expected positions
        assert!((box1_final_reference.x - 5.0).abs() < 1e-6);
        assert!((box1_final_reference.y + 5.0).abs() < 1e-6); // -5.0

        assert!((box2_final_reference.x + 5.0).abs() < 1e-6); // -5.0
        assert!((box2_final_reference.y + 5.0).abs() < 1e-6); // -5.0

        // Verify that combined transforms produce the same results as sequential application
        assert!((box1_final_combined.x - box1_final_reference.x).abs() < 1e-6);
        assert!((box1_final_combined.y - box1_final_reference.y).abs() < 1e-6);

        assert!((box2_final_combined.x - box2_final_reference.x).abs() < 1e-6);
        assert!((box2_final_combined.y - box2_final_reference.y).abs() < 1e-6);

        // Add test points around each box to visualize the rotation
        let test_points1 = [
            Point2::new(-6.0, -5.0), // Left of box1
            Point2::new(-5.0, -6.0), // Below box1
            Point2::new(-4.0, -5.0), // Right of box1
            Point2::new(-5.0, -4.0), // Above box1
        ];

        let test_points2 = [
            Point2::new(-6.0, 5.0), // Left of box2
            Point2::new(-5.0, 6.0), // Above box2
            Point2::new(-4.0, 5.0), // Right of box2
            Point2::new(-5.0, 4.0), // Below box2
        ];

        println!("\nBox1 test points:");
        for (i, point) in test_points1.iter().enumerate() {
            let after_local = transform1.apply_to_position_matrix(*point);
            let final_pos = transform_both.apply_to_position_matrix(after_local);
            let combined_pos = combined1.apply_to_position_matrix(*point);

            println!(
                "Point {}: Original=({:.2}, {:.2}), Final=({:.2}, {:.2}), Combined=({:.2}, {:.2})",
                i + 1,
                point.x,
                point.y,
                final_pos.x,
                final_pos.y,
                combined_pos.x,
                combined_pos.y
            );

            // Verify combined transform gives same result
            assert!((final_pos.x - combined_pos.x).abs() < 1e-6);
            assert!((final_pos.y - combined_pos.y).abs() < 1e-6);
        }

        println!("\nBox2 test points:");
        for (i, point) in test_points2.iter().enumerate() {
            let after_local = transform2.apply_to_position_matrix(*point);
            let final_pos = transform_both.apply_to_position_matrix(after_local);
            let combined_pos = combined2.apply_to_position_matrix(*point);

            println!(
                "Point {}: Original=({:.2}, {:.2}), Final=({:.2}, {:.2}), Combined=({:.2}, {:.2})",
                i + 1,
                point.x,
                point.y,
                final_pos.x,
                final_pos.y,
                combined_pos.x,
                combined_pos.y
            );

            // Verify combined transform gives same result
            assert!((final_pos.x - combined_pos.x).abs() < 1e-6);
            assert!((final_pos.y - combined_pos.y).abs() < 1e-6);
        }

        // Final verification after all transformations
        // After local rotation and global rotation, box1 should be at (5, -5)
        // After local rotation and global rotation, box2 should be at (-5, -5)
        assert!((box1_final_reference.x - 5.0).abs() < 1e-6);
        assert!((box1_final_reference.y + 5.0).abs() < 1e-6); // -5.0

        assert!((box2_final_reference.x + 5.0).abs() < 1e-6); // -5.0
        assert!((box2_final_reference.y + 5.0).abs() < 1e-6); // -5.0
    }

    #[test]
    fn test_combined_transforms_complex() {
        // Test a more complex scenario with rotation, scaling, and offset
        let transform1 = GerberTransform {
            rotation: PI / 6.0, // 30 degrees
            mirroring: Mirroring::default(),
            origin: Vector2::new(3.0, 4.0),
            offset: Vector2::new(1.0, 2.0),
            scale: 1.5,
        };

        let transform2 = GerberTransform {
            rotation: PI / 3.0, // 60 degrees
            mirroring: Mirroring::default(),
            origin: Vector2::new(-2.0, 5.0),
            offset: Vector2::new(3.0, -1.0),
            scale: 0.8,
        };

        // Test points
        let test_points = vec![
            Point2::new(0.0, 0.0),
            Point2::new(10.0, 0.0),
            Point2::new(0.0, 10.0),
            Point2::new(-5.0, -5.0),
        ];

        for point in test_points {
            // Apply transforms sequentially
            let intermediate = transform1.apply_to_position_matrix(point);
            let final_reference = transform2.apply_to_position_matrix(intermediate);

            // Apply combined transform
            let combined = transform1.combine(&transform2);
            let final_combined = combined.apply_to_position_matrix(point);

            // Verify results match
            assert!((final_combined.x - final_reference.x).abs() < 1e-6);
            assert!((final_combined.y - final_reference.y).abs() < 1e-6);
        }
    }

    #[test]
    fn test_mirroring_transforms() {
        // Create transform with x-mirroring
        let mirror_x = GerberTransform {
            rotation: 0.0,
            mirroring: Mirroring {
                x: true,
                y: false,
            },
            origin: Vector2::new(0.0, 0.0),
            offset: Vector2::new(0.0, 0.0),
            scale: 1.0,
        };

        // Create a rotation transform
        let rotate_45 = GerberTransform {
            rotation: PI / 4.0, // 45 degrees
            mirroring: Mirroring::default(),
            origin: Vector2::new(0.0, 0.0),
            offset: Vector2::new(0.0, 0.0),
            scale: 1.0,
        };

        // Test point
        let point = Point2::new(3.0, 4.0);

        // Apply transforms sequentially
        let intermediate = mirror_x.apply_to_position_matrix(point);
        let final_reference = rotate_45.apply_to_position_matrix(intermediate);

        // Apply combined transform
        let combined = mirror_x.combine(&rotate_45);
        let final_combined = combined.apply_to_position_matrix(point);

        // Verify results match
        assert!((final_combined.x - final_reference.x).abs() < 1e-6);
        assert!((final_combined.y - final_reference.y).abs() < 1e-6);

        // Verify mirroring was detected in the combined transform
        assert_eq!(combined.mirroring.x, true);
    }

    #[test]
    fn test_scaling_transforms() {
        // Create transform with scaling
        let scale_2x = GerberTransform {
            rotation: 0.0,
            mirroring: Mirroring::default(),
            origin: Vector2::new(0.0, 0.0),
            offset: Vector2::new(0.0, 0.0),
            scale: 2.0,
        };

        // Create transform with offset
        let offset_10_20 = GerberTransform {
            rotation: 0.0,
            mirroring: Mirroring::default(),
            origin: Vector2::new(0.0, 0.0),
            offset: Vector2::new(10.0, 20.0),
            scale: 1.0,
        };

        // Test point
        let point = Point2::new(3.0, 4.0);

        // Apply transforms sequentially
        let intermediate = scale_2x.apply_to_position_matrix(point);
        let final_reference = offset_10_20.apply_to_position_matrix(intermediate);

        // Apply combined transform
        let combined = scale_2x.combine(&offset_10_20);
        let final_combined = combined.apply_to_position_matrix(point);

        // Verify results match
        assert!((final_combined.x - final_reference.x).abs() < 1e-6);
        assert!((final_combined.y - final_reference.y).abs() < 1e-6);

        // Verify scaling was preserved in the combined transform
        assert!((combined.scale - 2.0).abs() < 1e-6);
    }

    #[test]
    fn test_multiple_combined_transforms() {
        // Create three transforms
        let transform1 = GerberTransform {
            rotation: PI / 4.0, // 45 degrees
            mirroring: Mirroring::default(),
            origin: Vector2::new(-5.0, 0.0),
            offset: Vector2::new(0.0, 0.0),
            scale: 1.0,
        };

        let transform2 = GerberTransform {
            rotation: PI / 2.0, // 90 degrees
            mirroring: Mirroring::default(),
            origin: Vector2::new(0.0, 0.0),
            offset: Vector2::new(0.0, 0.0),
            scale: 1.0,
        };

        let transform3 = GerberTransform {
            rotation: 0.0,
            mirroring: Mirroring::default(),
            origin: Vector2::new(0.0, 0.0),
            offset: Vector2::new(10.0, 10.0),
            scale: 2.0,
        };

        // Test point
        let point = Point2::new(-5.0, 0.0);

        // Apply transforms sequentially
        let step1 = transform1.apply_to_position_matrix(point);
        let step2 = transform2.apply_to_position_matrix(step1);
        let final_reference = transform3.apply_to_position_matrix(step2);

        // Apply combined transforms in steps
        let combined_1_2 = transform1.combine(&transform2);
        let combined_all = combined_1_2.combine(&transform3);
        let final_combined = combined_all.apply_to_position_matrix(point);

        // Verify results match
        assert!((final_combined.x - final_reference.x).abs() < 1e-6);
        assert!((final_combined.y - final_reference.y).abs() < 1e-6);
    }

    #[test]
    fn test_rotation_around_different_centers() {
        // This test specifically targets the original issue

        // Box 1 at (-5, 0)
        let box1_position = Point2::new(-5.0, 0.0);

        // Box 2 at (5, 0)
        let box2_position = Point2::new(5.0, 0.0);

        // Local rotations (45°) around each box's position
        let box1_local_rot = GerberTransform {
            rotation: PI / 4.0, // 45 degrees
            mirroring: Mirroring::default(),
            origin: Vector2::new(-5.0, 0.0), // Rotate around box1's position
            offset: Vector2::new(0.0, 0.0),
            scale: 1.0,
        };

        let box2_local_rot = GerberTransform {
            rotation: PI / 4.0, // 45 degrees
            mirroring: Mirroring::default(),
            origin: Vector2::new(5.0, 0.0), // Rotate around box2's position
            offset: Vector2::new(0.0, 0.0),
            scale: 1.0,
        };

        // Global rotation (90°) around (0, 0)
        let global_rot = GerberTransform {
            rotation: PI / 2.0, // 90 degrees
            mirroring: Mirroring::default(),
            origin: Vector2::new(0.0, 0.0), // Rotate around the origin
            offset: Vector2::new(0.0, 0.0),
            scale: 1.0,
        };

        // Apply transforms sequentially
        let box1_after_local = box1_local_rot.apply_to_position_matrix(box1_position);
        let box1_after_global = global_rot.apply_to_position_matrix(box1_after_local);

        let box2_after_local = box2_local_rot.apply_to_position_matrix(box2_position);
        let box2_after_global = global_rot.apply_to_position_matrix(box2_after_local);

        // Apply combined transforms
        let box1_combined = box1_local_rot.combine(&global_rot);
        let box2_combined = box2_local_rot.combine(&global_rot);

        let box1_after_combined = box1_combined.apply_to_position_matrix(box1_position);
        let box2_after_combined = box2_combined.apply_to_position_matrix(box2_position);

        println!("Sequential for box1: {:?}", [box1_after_global.x, box1_after_global.y]);
        println!("Combined for box1: {:?}", [
            box1_after_combined.x,
            box1_after_combined.y
        ]);
        println!("Sequential for box2: {:?}", [box2_after_global.x, box2_after_global.y]);
        println!("Combined for box2: {:?}", [
            box2_after_combined.x,
            box2_after_combined.y
        ]);

        println!(
            "box1_combined: rotation={}, offset={:?}, origin={:?}, scale={}",
            box1_combined.rotation,
            [box1_combined.offset.x, box1_combined.offset.y],
            [box1_combined.origin.x, box1_combined.origin.y],
            box1_combined.scale
        );

        println!(
            "box2_combined: rotation={}, offset={:?}, origin={:?}, scale={}",
            box2_combined.rotation,
            [box2_combined.offset.x, box2_combined.offset.y],
            [box2_combined.origin.x, box2_combined.origin.y],
            box2_combined.scale
        );

        // Verify that combined transforms produce the same results as sequential application
        assert!((box1_after_combined.x - box1_after_global.x).abs() < 1e-6);
        assert!((box1_after_combined.y - box1_after_global.y).abs() < 1e-6);

        assert!((box2_after_combined.x - box2_after_global.x).abs() < 1e-6);
        assert!((box2_after_combined.y - box2_after_global.y).abs() < 1e-6);

        // Verify that the boxes end up at the expected positions (~0, -5) and (~0, 5)
        assert!((box1_after_global.x).abs() < 1e-6);
        assert!((box1_after_global.y - -5.0).abs() < 1e-6);

        assert!((box2_after_global.x).abs() < 1e-6);
        assert!((box2_after_global.y - 5.0).abs() < 1e-6);
    }
}

/// Extension trait for checking properties of a Matrix3<f64> transformation
pub trait Matrix3TransformExt {
    /// Check if this transformation matrix represents an axis-aligned transform
    /// (rotations of only 0, 90, 180, or 270 degrees)
    fn is_axis_aligned(&self) -> bool;

    /// Extract the rotation angle from the transformation matrix in radians
    fn extract_rotation_angle(&self) -> f64;

    /// Check if this transformation matrix represents a 90° or 270° rotation
    /// (optionally with uniform scaling)
    fn is_90_or_270_rotation(&self) -> bool;
    fn is_0_or_180_rotation(&self) -> bool;

    fn get_axis_aligned_angle(&self) -> Option<i32>;
}

impl Matrix3TransformExt for Matrix3<f64> {
    fn is_axis_aligned(&self) -> bool {
        // Extract the 2x2 rotation/scaling matrix
        let a = self[(0, 0)];
        let b = self[(0, 1)];
        let c = self[(1, 0)];
        let d = self[(1, 1)];

        // For axis-aligned transforms, either:
        // 1. a and d are non-zero, b and c are close to zero (0° or 180° rotation)
        // 2. b and c are non-zero, a and d are close to zero (90° or 270° rotation)

        // Check first case: close to 0° or 180° rotation
        let case1 =
            (b.abs() < f64::EPSILON && c.abs() < f64::EPSILON) && (a.abs() > f64::EPSILON || d.abs() > f64::EPSILON);

        // Check second case: close to 90° or 270° rotation
        let case2 =
            (a.abs() < f64::EPSILON && d.abs() < f64::EPSILON) && (b.abs() > f64::EPSILON || c.abs() > f64::EPSILON);

        // Check if matrix represents one of these cases
        case1 || case2
    }

    fn extract_rotation_angle(&self) -> f64 {
        // Extract the 2x2 rotation/scaling matrix
        let a = self[(0, 0)];
        let b = self[(0, 1)];
        let c = self[(1, 0)];
        let d = self[(1, 1)];

        // Handle scale factors by normalizing the matrix elements
        let det = (a * d - b * c).sqrt();
        let a_norm = if det.abs() > f64::EPSILON { a / det } else { a };
        let b_norm = if det.abs() > f64::EPSILON { b / det } else { b };

        // Calculate rotation angle (account for possible reflections)
        let angle = b_norm.atan2(a_norm);

        // Normalize to [0, 2π)
        (angle + 2.0 * PI) % (2.0 * PI)
    }

    fn is_90_or_270_rotation(&self) -> bool {
        // For a pure 90° rotation, the matrix has the form:
        // ```
        //    [ 0, -s,  tx ]
        //    [ s,  0,  ty ]
        //    [ 0,  0,   1 ]
        // ```
        //
        // For a pure 270° rotation, the matrix has the form:
        // ```
        //    [  0, s,  tx ]
        //    [ -s, 0,  ty ]
        //    [  0, 0,   1 ]
        // ```

        // Extract the 2x2 rotation/scaling matrix
        let a = self[(0, 0)];
        let b = self[(0, 1)];
        let c = self[(1, 0)];
        let d = self[(1, 1)];

        // For a 90° or 270° rotation (with possible uniform scaling):
        // 1. The diagonal elements (a and d) should be close to zero
        // 2. The off-diagonal elements (b and c) should have opposite signs
        // 3. |b| should be approximately equal to |c| (accounting for uniform scaling)

        // Check if diagonal elements are approximately zero
        let diagonals_are_zero = a.abs() < f64::EPSILON && d.abs() < f64::EPSILON;

        // Check if off-diagonal elements are non-zero and have opposite signs
        let off_diagonals_opposite_sign = (b * c) < 0.0 && b.abs() > f64::EPSILON && c.abs() > f64::EPSILON;

        // Check if the magnitude of off-diagonal elements is approximately equal
        // (allowing for some numerical error)
        let relative_diff = if c.abs() > f64::EPSILON {
            (b.abs() / c.abs() - 1.0).abs()
        } else {
            f64::INFINITY
        };
        let magnitudes_equal = relative_diff < 1e-6;

        // All conditions must be true
        diagonals_are_zero && off_diagonals_opposite_sign && magnitudes_equal
    }

    fn is_0_or_180_rotation(&self) -> bool {
        // Extract the 2x2 rotation/scaling matrix
        let a = self[(0, 0)];
        let b = self[(0, 1)];
        let c = self[(1, 0)];
        let d = self[(1, 1)];

        // For a 0° or 180° rotation (with possible uniform scaling):
        // 1. The off-diagonal elements (b and c) should be close to zero
        // 2. The diagonal elements (a and d) should have the same sign for 0°
        //    or opposite signs for 180°
        // 3. |a| should be approximately equal to |d| (accounting for uniform scaling)

        // Check if off-diagonal elements are approximately zero
        let off_diagonals_are_zero = b.abs() < f64::EPSILON && c.abs() < f64::EPSILON;

        // Check if diagonal elements are non-zero
        let diagonals_are_nonzero = a.abs() > f64::EPSILON && d.abs() > f64::EPSILON;

        // Check if the magnitude of diagonal elements is approximately equal
        let relative_diff = if d.abs() > f64::EPSILON {
            (a.abs() / d.abs() - 1.0).abs()
        } else {
            f64::INFINITY
        };
        let magnitudes_equal = relative_diff < 1e-6;

        // All conditions must be true
        off_diagonals_are_zero && diagonals_are_nonzero && magnitudes_equal
    }

    /// Determine the axis-aligned rotation angle (0°, 90°, 180°, or 270°)
    /// Returns None if the matrix is not an axis-aligned rotation
    fn get_axis_aligned_angle(&self) -> Option<i32> {
        if self.is_0_or_180_rotation() {
            // Determine if it's 0° or 180° by checking the sign of diagonal elements
            let a = self[(0, 0)];
            let d = self[(1, 1)];

            // Same sign indicates 0°, opposite sign indicates 180°
            if a * d > 0.0 { Some(0) } else { Some(180) }
        } else if self.is_90_or_270_rotation() {
            // Determine if it's 90° or 270° by checking the sign of off-diagonal elements
            let b = self[(0, 1)];
            let c = self[(1, 0)];

            // For standard rotation matrices:
            // 90° rotation has b < 0 and c > 0
            // 270° rotation has b > 0 and c < 0
            if b < 0.0 && c > 0.0 { Some(90) } else { Some(270) }
        } else {
            None
        }
    }
}

/// This is to support the deprecated MI, SF, OF, IR and AS commands.
///
/// Transform order, as per spec, is: MI, SF, OF, IR and AS.
/// aka Mirroring, Scaling, Offset, Rotation and Axis Select.
///
/// Rotation is always around the origin, 0,0
#[derive(Clone, Debug)]
pub struct GerberImageTransform {
    /// A = X, B = Y.
    pub mirroring: ImageMirroring,
    pub offset: Vector2<f64>,
    pub scale: Vector2<f64>,
    /// rotation in radians, positive = counter-clockwise
    pub rotation: f64,
    pub axis_select: AxisSelect,
}

impl Default for GerberImageTransform {
    fn default() -> Self {
        Self {
            mirroring: ImageMirroring::default(),
            offset: Vector2::new(0.0, 0.0),
            scale: Vector2::new(1.0, 1.0),
            rotation: 0.0,
            axis_select: AxisSelect::default(),
        }
    }
}

impl GerberImageTransform {
    /// Converts this transform to a 3x3 homogeneous transformation matrix
    #[rustfmt::skip]
    pub fn to_matrix(&self) -> Matrix3<f64> {

        let [mirror_x, mirror_y] = match self.mirroring {
            ImageMirroring::None => [1.0, 1.0],
            ImageMirroring::A => [-1.0, 1.0],
            ImageMirroring::B => [1.0, -1.0],
            ImageMirroring::AB => [-1.0, -1.0],
        };
        let mirroring_matrix = Matrix3::new(
            mirror_x, 0.0, 0.0,
            0.0, mirror_y, 0.0,
            0.0, 0.0, 1.0
        );

        let scaling_matrix = Matrix3::new(
            self.scale.x, 0.0, 0.0,
            0.0, self.scale.y, 0.0,
            0.0, 0.0, 1.0
        );

        let rad = self.rotation;
        let cos_rad = rad.cos();
        let sin_rad = rad.sin();
        let rotation_matrix = Matrix3::new(
            cos_rad, -sin_rad, 0.0,
            sin_rad, cos_rad, 0.0,
            0.0, 0.0, 1.0
        );

        let translate_offset = Matrix3::new(
            1.0, 0.0, self.offset.x,
            0.0, 1.0, self.offset.y,
            0.0, 0.0, 1.0
        );

        let axis_assignment_matrix = {
            match self.axis_select {
                AxisSelect::AXBY => {
                    let identity_matrix = Matrix3::identity();
                    identity_matrix
                }
                AxisSelect::AYBX => {
                    let swap_matrix = Matrix3::new(
                        0.0, 1.0, 0.0,  // First row
                        1.0, 0.0, 0.0,  // Second row
                        0.0, 0.0, 1.0   // Homogeneous row
                    );
                    swap_matrix
                }
            }
        };

        mirroring_matrix * scaling_matrix * translate_offset * rotation_matrix * axis_assignment_matrix
    }
}

#[derive(Clone, Debug, Copy)]
pub enum AxisAssignment {
    AXBY,
    AYBX,
}

impl Default for AxisAssignment {
    fn default() -> Self {
        AxisAssignment::AXBY
    }
}