inner-space 0.3.0

use std::ops::{Add, Div, Mul, Neg, Sub};

use inner_space::{DotProduct, InnerSpace, VectorSpace, distance};
use scalars::Zero;

#[derive(Clone, Copy, PartialEq, Debug)]
struct Vector {
    x: f32,
    y: f32,
}

impl Vector {
    fn new(x: f32, y: f32) -> Self {
        Self { x, y }
    }
}

impl Add for Vector {
    type Output = Self;

    fn add(self, other: Self) -> Self {
        Self {
            x: self.x + other.x,
            y: self.y + other.y,
        }
    }
}

impl Sub for Vector {
    type Output = Self;

    fn sub(self, other: Self) -> Self {
        Self {
            x: self.x - other.x,
            y: self.y - other.y,
        }
    }
}

impl Mul<f32> for Vector {
    type Output = Self;

    fn mul(self, other: f32) -> Self {
        Self {
            x: self.x * other,
            y: self.y * other,
        }
    }
}

impl Div<f32> for Vector {
    type Output = Self;

    fn div(self, other: f32) -> Self {
        Self {
            x: self.x / other,
            y: self.y / other,
        }
    }
}

impl Neg for Vector {
    type Output = Self;

    fn neg(self) -> Self {
        Self {
            x: -self.x,
            y: -self.y,
        }
    }
}

impl Zero for Vector {
    fn zero() -> Self {
        Self { x: 0.0, y: 0.0 }
    }

    fn is_zero(&self) -> bool {
        self.x == 0.0 && self.y == 0.0
    }
}

impl VectorSpace for Vector {
    type Scalar = f32;
}

impl DotProduct for Vector {
    type Output = f32;

    fn dot(&self, other: &Self) -> f32 {
        self.x * other.x + self.y * other.y
    }
}

#[test]
fn test_distance() {
    let a = Vector::new(-1.0, 2.0);
    let b = Vector::new(2.0, 6.0);

    assert_eq!(distance(a, b), 5.0);
}

#[test]
fn test_project_reject_reflect() {
    let a = Vector::new(-1.0, 3.0);
    let b = Vector::new(0.0, 6.0);

    assert_eq!(a.project(b), Vector::new(0.0, 3.0));
    assert_eq!(a.reject(b), Vector::new(-1.0, 0.0));
    assert_eq!(a.reflect(b), Vector::new(1.0, 3.0));
}