1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at https://mozilla.org/MPL/2.0/. */

//! Computed percentages.

use crate::values::animated::ToAnimatedValue;
use crate::values::generics::NonNegative;
use crate::values::specified::percentage::ToPercentage;
use crate::values::{serialize_normalized_percentage, CSSFloat};
use crate::Zero;
use std::fmt;
use style_traits::{CssWriter, ToCss};

/// A computed percentage.
#[derive(
    Animate,
    Clone,
    ComputeSquaredDistance,
    Copy,
    Debug,
    Default,
    Deserialize,
    MallocSizeOf,
    PartialEq,
    PartialOrd,
    Serialize,
    SpecifiedValueInfo,
    ToAnimatedValue,
    ToAnimatedZero,
    ToComputedValue,
    ToResolvedValue,
    ToShmem,
)]
#[repr(C)]
pub struct Percentage(pub CSSFloat);

impl Percentage {
    /// 100%
    #[inline]
    pub fn hundred() -> Self {
        Percentage(1.)
    }

    /// Returns the absolute value for this percentage.
    #[inline]
    pub fn abs(&self) -> Self {
        Percentage(self.0.abs())
    }

    /// Clamps this percentage to a non-negative percentage.
    #[inline]
    pub fn clamp_to_non_negative(self) -> Self {
        Percentage(self.0.max(0.))
    }
}

impl Zero for Percentage {
    fn zero() -> Self {
        Percentage(0.)
    }

    fn is_zero(&self) -> bool {
        self.0 == 0.
    }
}

impl ToPercentage for Percentage {
    fn to_percentage(&self) -> CSSFloat {
        self.0
    }
}

impl std::ops::AddAssign for Percentage {
    fn add_assign(&mut self, other: Self) {
        self.0 += other.0
    }
}

impl std::ops::Add for Percentage {
    type Output = Self;

    fn add(self, other: Self) -> Self {
        Percentage(self.0 + other.0)
    }
}

impl std::ops::Sub for Percentage {
    type Output = Self;

    fn sub(self, other: Self) -> Self {
        Percentage(self.0 - other.0)
    }
}

impl std::ops::Rem for Percentage {
    type Output = Self;

    fn rem(self, other: Self) -> Self {
        Percentage(self.0 % other.0)
    }
}

impl ToCss for Percentage {
    fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result
    where
        W: fmt::Write,
    {
        serialize_normalized_percentage(self.0, dest)
    }
}

/// A wrapper over a `Percentage`, whose value should be clamped to 0.
pub type NonNegativePercentage = NonNegative<Percentage>;

impl NonNegativePercentage {
    /// 100%
    #[inline]
    pub fn hundred() -> Self {
        NonNegative(Percentage::hundred())
    }
}

impl ToAnimatedValue for NonNegativePercentage {
    type AnimatedValue = Percentage;

    #[inline]
    fn to_animated_value(self, _: &crate::values::animated::Context) -> Self::AnimatedValue {
        self.0
    }

    #[inline]
    fn from_animated_value(animated: Self::AnimatedValue) -> Self {
        NonNegative(animated.clamp_to_non_negative())
    }
}