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
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192

use std::time::Duration;

use crate::raw::root::RED4ext as red;

#[derive(Default, Clone, Copy)]
#[repr(transparent)]
pub struct EngineTime(red::EngineTime);

impl EngineTime {
    pub fn is_valid(&self) -> bool {
        self.0.unk00 != [0; 8]
    }

    pub fn as_secs_f64(&self) -> f64 {
        f64::from_ne_bytes(self.0.unk00)
    }
}

impl std::ops::AddAssign<f64> for EngineTime {
    /// # Panics
    ///
    /// Panics if the sum ends up being `f64::NAN`, `f64::INFINITY` or `f64::NEG_INFINITY`.
    fn add_assign(&mut self, rhs: f64) {
        let current = self.as_secs_f64();
        let addition = current + rhs;
        assert!(!addition.is_infinite(), "EngineTime cannot be infinity");
        assert!(!addition.is_nan(), "EngineTime cannot be NaN");
        self.0.unk00 = addition.to_ne_bytes();
    }
}

impl std::ops::Add<f64> for EngineTime {
    type Output = EngineTime;

    /// # Panics
    ///
    /// Panics if the sum ends up being `f64::NAN`, `f64::INFINITY` or `f64::NEG_INFINITY`.
    fn add(self, rhs: f64) -> Self::Output {
        use std::ops::AddAssign;
        let mut copy = self;
        copy.add_assign(rhs);
        copy
    }
}

impl std::ops::SubAssign<f64> for EngineTime {
    /// # Panics
    ///
    /// Panics if the sum ends up being `f64::NAN`, `f64::INFINITY` or `f64::NEG_INFINITY`.
    fn sub_assign(&mut self, rhs: f64) {
        let current = self.as_secs_f64();
        let substraction = current - rhs;
        assert!(!substraction.is_infinite(), "EngineTime cannot be infinity");
        assert!(!substraction.is_nan(), "EngineTime cannot be NaN");
        self.0.unk00 = substraction.to_ne_bytes();
    }
}

impl std::ops::Sub<f64> for EngineTime {
    type Output = EngineTime;

    /// # Panics
    ///
    /// Panics if the sum ends up being `f64::NAN`, `f64::INFINITY` or `f64::NEG_INFINITY`.
    fn sub(self, rhs: f64) -> Self::Output {
        use std::ops::SubAssign;
        let mut copy = self;
        copy.sub_assign(rhs);
        copy
    }
}

impl PartialEq for EngineTime {
    fn eq(&self, other: &Self) -> bool {
        self.0.unk00.eq(&other.0.unk00)
    }
}

impl PartialOrd for EngineTime {
    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
        self.0.unk00.partial_cmp(&other.0.unk00)
    }
}

impl TryFrom<f64> for EngineTime {
    type Error = EngineTimeError;

    fn try_from(value: f64) -> Result<Self, Self::Error> {
        if value.is_infinite() {
            return Err(EngineTimeError::OutOfBounds);
        }
        if value.is_nan() {
            return Err(EngineTimeError::NotANumber);
        }
        Ok(Self(red::EngineTime {
            unk00: value.to_ne_bytes(),
        }))
    }
}

impl From<EngineTime> for f64 {
    fn from(EngineTime(red::EngineTime { unk00 }): EngineTime) -> Self {
        Self::from_ne_bytes(unk00)
    }
}

impl TryFrom<Duration> for EngineTime {
    type Error = EngineTimeError;

    fn try_from(value: Duration) -> Result<Self, Self::Error> {
        let value = value.as_secs_f64();
        value.try_into()
    }
}

impl std::ops::Add<Duration> for EngineTime {
    type Output = Self;

    fn add(self, rhs: Duration) -> Self::Output {
        self.add(rhs.as_secs_f64())
    }
}

impl std::ops::AddAssign<Duration> for EngineTime {
    fn add_assign(&mut self, rhs: Duration) {
        self.add_assign(rhs.as_secs_f64());
    }
}

impl std::ops::Sub<Duration> for EngineTime {
    type Output = Self;

    fn sub(self, rhs: Duration) -> Self::Output {
        self.sub(rhs.as_secs_f64())
    }
}

impl std::ops::SubAssign<Duration> for EngineTime {
    fn sub_assign(&mut self, rhs: Duration) {
        self.sub_assign(rhs.as_secs_f64());
    }
}

#[derive(Debug)]
pub enum EngineTimeError {
    OutOfBounds,
    NotANumber,
}

impl std::fmt::Display for EngineTimeError {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        write!(
            f,
            "{}",
            match self {
                Self::OutOfBounds => "invalid infinite or negative infinite floating-point",
                Self::NotANumber => "invalid NaN",
            }
        )
    }
}

impl std::error::Error for EngineTimeError {}

#[cfg(test)]
mod tests {
    use std::time::Duration;

    use super::EngineTime;

    #[test]
    fn bounds() {
        assert!(EngineTime::try_from(f64::INFINITY).is_err());
        assert!(EngineTime::try_from(f64::NEG_INFINITY).is_err());

        let before = EngineTime::try_from(f64::MAX).unwrap();
        let after = before + Duration::from_millis(1);
        assert_eq!(after.as_secs_f64(), f64::MAX);

        let before = EngineTime::try_from(f64::MIN).unwrap();
        let after = before - Duration::from_millis(1);
        assert_eq!(after.as_secs_f64(), f64::MIN);
    }

    #[test]
    fn math() {
        let mut time = EngineTime::try_from(3.2).unwrap();
        time += Duration::from_secs_f64(4.1);

        assert_eq!(time.as_secs_f64(), 7.3);
    }
}