lyon_svg 0.17.2

use crate::parser::{PathParser, PathSegment};

use crate::path::builder::*;
use crate::path::geom::Arc;
use crate::path::math::{point, vector, Angle, Point, Vector};
use crate::path::ArcFlags;

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

#[derive(Clone, Debug, PartialEq)]
pub struct ParseError;

/// Builds path object using an SvgPathBuilder and a list of commands.
/// Once the path is built you can tessellate it.
///
/// The [SvgPathBuilder](trait.SvgPathBuilder.html) Adds to [PathBuilder](trait.PathBuilder.html)
/// the rest of the [SVG path](https://svgwg.org/specs/paths/) commands.
///
/// # Examples
///
/// ```
/// # extern crate lyon_svg as svg;
/// # extern crate lyon_path;
/// # use lyon_path::Path;
/// # use svg::path_utils::build_path;
/// # fn main() {
/// // Create a simple path.
/// let commands = &"M 0 0 L 10 0 L 10 10 L 0 10 z";
/// let svg_builder = Path::builder().with_svg();
/// let path = build_path(svg_builder, commands);
/// # }
/// ```
pub fn build_path<Builder>(mut builder: Builder, src: &str) -> Result<Builder::PathType, ParseError>
where
    Builder: SvgPathBuilder + Build,
{
    for item in PathParser::from(src) {
        match item {
            Ok(segment) => svg_event(&segment, &mut builder),
            Err(_) => return Err(ParseError),
        }
    }

    Ok(builder.build())
}

fn svg_event<Builder>(token: &PathSegment, builder: &mut Builder)
where
    Builder: SvgPathBuilder,
{
    fn vec2(x: f64, y: f64) -> Vector {
        vector(x as f32, y as f32)
    }
    fn point2(x: f64, y: f64) -> Point {
        point(x as f32, y as f32)
    }
    match *token {
        PathSegment::MoveTo { abs: true, x, y } => {
            builder.move_to(point2(x, y));
        }
        PathSegment::MoveTo { abs: false, x, y } => {
            builder.relative_move_to(vec2(x, y));
        }
        PathSegment::LineTo { abs: true, x, y } => {
            builder.line_to(point2(x, y));
        }
        PathSegment::LineTo { abs: false, x, y } => {
            builder.relative_line_to(vec2(x, y));
        }
        PathSegment::HorizontalLineTo { abs: true, x } => {
            builder.horizontal_line_to(x as f32);
        }
        PathSegment::HorizontalLineTo { abs: false, x } => {
            builder.relative_horizontal_line_to(x as f32);
        }
        PathSegment::VerticalLineTo { abs: true, y } => {
            builder.vertical_line_to(y as f32);
        }
        PathSegment::VerticalLineTo { abs: false, y } => {
            builder.relative_vertical_line_to(y as f32);
        }
        PathSegment::CurveTo {
            abs: true,
            x1,
            y1,
            x2,
            y2,
            x,
            y,
        } => {
            builder.cubic_bezier_to(point2(x1, y1), point2(x2, y2), point2(x, y));
        }
        PathSegment::CurveTo {
            abs: false,
            x1,
            y1,
            x2,
            y2,
            x,
            y,
        } => {
            builder.relative_cubic_bezier_to(vec2(x1, y1), vec2(x2, y2), vec2(x, y));
        }
        PathSegment::SmoothCurveTo {
            abs: true,
            x2,
            y2,
            x,
            y,
        } => {
            builder.smooth_cubic_bezier_to(point2(x2, y2), point2(x, y));
        }
        PathSegment::SmoothCurveTo {
            abs: false,
            x2,
            y2,
            x,
            y,
        } => {
            builder.smooth_relative_cubic_bezier_to(vec2(x2, y2), vec2(x, y));
        }
        PathSegment::Quadratic {
            abs: true,
            x1,
            y1,
            x,
            y,
        } => {
            builder.quadratic_bezier_to(point2(x1, y1), point2(x, y));
        }
        PathSegment::Quadratic {
            abs: false,
            x1,
            y1,
            x,
            y,
        } => {
            builder.relative_quadratic_bezier_to(vec2(x1, y1), vec2(x, y));
        }
        PathSegment::SmoothQuadratic { abs: true, x, y } => {
            builder.smooth_quadratic_bezier_to(point2(x, y));
        }
        PathSegment::SmoothQuadratic { abs: false, x, y } => {
            builder.smooth_relative_quadratic_bezier_to(vec2(x, y));
        }
        PathSegment::EllipticalArc {
            abs: true,
            rx,
            ry,
            x_axis_rotation,
            large_arc,
            sweep,
            x,
            y,
        } => {
            builder.arc_to(
                vec2(rx, ry),
                Angle::degrees(x_axis_rotation as f32),
                ArcFlags {
                    large_arc: large_arc,
                    sweep: sweep,
                },
                point2(x, y),
            );
        }
        PathSegment::EllipticalArc {
            abs: false,
            rx,
            ry,
            x_axis_rotation,
            large_arc,
            sweep,
            x,
            y,
        } => {
            builder.relative_arc_to(
                vec2(rx, ry),
                Angle::degrees(x_axis_rotation as f32),
                ArcFlags {
                    large_arc: large_arc,
                    sweep: sweep,
                },
                vec2(x, y),
            );
        }
        PathSegment::ClosePath { .. } => {
            builder.close();
        }
    }
}

/// An `SvgPathBuilder` that builds a `String` representation of the path
/// using the SVG syntax.
///
/// No effort is put into making the serializer fast or make the
/// output compact. Intended primarily for debugging purposes.
pub struct PathSerializer {
    path: String,
    current: Point,
}

impl PathSerializer {
    pub fn new() -> Self {
        PathSerializer {
            path: String::new(),
            current: point(0.0, 0.0),
        }
    }

    pub fn arc(&mut self, center: Point, radii: Vector, sweep_angle: Angle, x_rotation: Angle) {
        let start_angle = (self.current - center).angle_from_x_axis() - x_rotation;
        let svg = Arc {
            center,
            radii,
            start_angle,
            sweep_angle,
            x_rotation,
        }
        .to_svg_arc();

        self.path += &format!(
            "A {} {} {} {} {} {} {}",
            radii.x,
            radii.y,
            svg.x_rotation.get(),
            svg.flags.large_arc,
            svg.flags.sweep,
            svg.to.x,
            svg.to.y
        );
    }
}

impl Build for PathSerializer {
    type PathType = String;

    fn build(self) -> String {
        self.path
    }
}

impl SvgPathBuilder for PathSerializer {
    fn move_to(&mut self, to: Point) {
        self.path += &format!("M {} {} ", to.x, to.y);
        self.current = to;
    }

    fn close(&mut self) {
        self.path.push_str("Z");
    }

    fn line_to(&mut self, to: Point) {
        self.path += &format!("L {} {} ", to.x, to.y);
        self.current = to;
    }

    fn quadratic_bezier_to(&mut self, ctrl: Point, to: Point) {
        self.path += &format!("Q {} {} {} {}", ctrl.x, ctrl.y, to.x, to.y);
    }

    fn cubic_bezier_to(&mut self, ctrl1: Point, ctrl2: Point, to: Point) {
        self.path += &format!(
            "C {} {} {} {} {} {}",
            ctrl1.x, ctrl1.y, ctrl2.x, ctrl2.y, to.x, to.y
        );
    }

    fn relative_move_to(&mut self, to: Vector) {
        self.path += &format!("m {} {} ", to.x, to.y);
    }

    fn relative_line_to(&mut self, to: Vector) {
        self.path += &format!("l {} {} ", to.x, to.y);
    }

    fn relative_quadratic_bezier_to(&mut self, ctrl: Vector, to: Vector) {
        self.path += &format!("q {} {} {} {}", ctrl.x, ctrl.y, to.x, to.y);
    }

    fn relative_cubic_bezier_to(&mut self, ctrl1: Vector, ctrl2: Vector, to: Vector) {
        self.path += &format!(
            "c {} {} {} {} {} {}",
            ctrl1.x, ctrl1.y, ctrl2.x, ctrl2.y, to.x, to.y
        );
    }

    fn smooth_cubic_bezier_to(&mut self, ctrl2: Point, to: Point) {
        self.path += &format!("S {} {} {} {}", ctrl2.x, ctrl2.y, to.x, to.y);
    }

    fn smooth_relative_cubic_bezier_to(&mut self, ctrl2: Vector, to: Vector) {
        self.path += &format!("s {} {} {} {}", ctrl2.x, ctrl2.y, to.x, to.y);
    }

    fn smooth_quadratic_bezier_to(&mut self, to: Point) {
        self.path += &format!("T {} {} ", to.x, to.y);
    }

    fn smooth_relative_quadratic_bezier_to(&mut self, to: Vector) {
        self.path += &format!("t {} {} ", to.x, to.y);
    }

    fn horizontal_line_to(&mut self, x: f32) {
        self.path += &format!("H {} ", x);
    }

    fn relative_horizontal_line_to(&mut self, dx: f32) {
        self.path += &format!("h {} ", dx);
    }

    fn vertical_line_to(&mut self, y: f32) {
        self.path += &format!("V {} ", y);
    }

    fn relative_vertical_line_to(&mut self, dy: f32) {
        self.path += &format!("v {} ", dy);
    }

    fn arc_to(&mut self, radii: Vector, x_rotation: Angle, flags: ArcFlags, to: Point) {
        self.path += &format!(
            "A {} {} {} {} {} {} {} ",
            radii.x,
            radii.y,
            x_rotation.get() * 180.0 / PI,
            if flags.large_arc { 1u32 } else { 0 },
            if flags.sweep { 1u32 } else { 0 },
            to.x,
            to.y
        );
    }

    fn relative_arc_to(&mut self, radii: Vector, x_rotation: Angle, flags: ArcFlags, to: Vector) {
        self.path += &format!(
            "a {} {} {} {} {} {} {} ",
            radii.x,
            radii.y,
            x_rotation.get() * 180.0 / PI,
            if flags.large_arc { 1u32 } else { 0 },
            if flags.sweep { 1u32 } else { 0 },
            to.x,
            to.y
        );
    }
}

#[test]
fn test_parse_error() {
    let invalid_commands = &"This is certainly not an SVG command string";
    let svg_builder = lyon_path::Path::builder().with_svg();
    assert!(build_path(svg_builder, invalid_commands).is_err());
}