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/// Trait converting price into points.
pub trait IntoPoints {
    fn into_points(self) -> u64;
}

impl IntoPoints for f64 {
    #[inline(always)]
    fn into_points(self) -> u64 {
        points(self)
    }
}

impl IntoPoints for f32 {
    #[inline(always)]
    fn into_points(self) -> u64 {
        points(self as f64)
    }
}

impl IntoPoints for u64 {
    #[inline(always)]
    fn into_points(self) -> u64 {
        self
    }
}

/// Trait converting points into price.
pub trait IntoPrice {
    fn into_price(self) -> f64;
}

impl IntoPrice for u64 {
    #[inline(always)]
    fn into_price(self) -> f64 {
        price(self)
    }
}

impl IntoPrice for f64 {
    fn into_price(self) -> f64 {
        self
    }
}

impl IntoPrice for f32 {
    fn into_price(self) -> f64 {
        self as f64
    }
}

/// Converts points to market price.
#[inline(always)]
pub fn points(price: f64) -> u64 {
    (price * 1e8).round() as u64
}

/// Converts market price to points.
#[inline(always)]
pub fn price(points: u64) -> f64 {
    points as f64 / 1e8
}

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

    #[test]
    fn price_points() {
        assert_eq!(points(1.0), 100000000);
        assert_eq!(points(2.55751896), 255751896);
        assert_eq!(points(0.00049245), 49245);
        assert_eq!(price(49245), 0.00049245);
        assert_eq!(points(0.015399360), 1539936);
        assert_eq!(price(1539936), 0.01539936);
        assert_eq!(points(0.09744111), 9744111);
        assert_eq!(price(9744111), 0.09744111);
        assert_eq!(points(0.15399360), 15399360);
        assert_eq!(price(15399360), 0.15399360);
        assert_eq!(points(0.00000354), 354);
        assert_eq!(price(354), 0.00000354);

        assert_eq!(points(0.20425743), 20425743);
        assert_eq!(price(20425743), 0.20425743);
        assert_eq!(points(0.03300001), 03300001);
        assert_eq!(price(03300001), 0.03300001);

        // xrp/btc price 12/26/2018
        assert_eq!(points(0.00010030), 10030);
        assert_eq!(price(10030), 0.00010030);
        // ada/btc price 12/26/2018
        assert_eq!(points(0.00001104), 1104);
        assert_eq!(price(1104), 0.00001104);
        // bnb commision
        assert_eq!(points(0.01497375), 1497375);
        assert_eq!(price(1497375), 0.01497375);
    }

    #[test]
    fn points_u64_max() {
        let r = points(0.00015370);
        let a = points(12e6);
        assert!(r * a < ::std::u64::MAX);
    }
}