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

use crate::platform::Duration as StdDuration;
use chrono::Duration;
use std::num::ParseFloatError;
use std::ops::{AddAssign, SubAssign};
use std::str::FromStr;

/// A Time Span represents a certain span of time.
#[derive(From, Add, Sub, Neg, Copy, Clone, Debug, Eq, PartialEq, Ord, PartialOrd)]
pub struct TimeSpan(Duration);

impl TimeSpan {
    /// Creates a new Time Span of zero length.
    pub fn zero() -> Self {
        Default::default()
    }

    /// Creates a new Time Span from a given amount of milliseconds.
    pub fn from_milliseconds(milliseconds: f64) -> Self {
        TimeSpan(Duration::microseconds((milliseconds * 1_000.0) as i64))
    }

    /// Creates a new Time Span from a given amount of seconds.
    pub fn from_seconds(seconds: f64) -> Self {
        TimeSpan(Duration::microseconds((seconds * 1_000_000.0) as i64))
    }

    /// Creates a new Time Span from a given amount of days.
    pub fn from_days(days: f64) -> Self {
        TimeSpan(Duration::microseconds(
            (days * (24.0 * 3600.0 * 1_000_000.0)) as i64,
        ))
    }

    /// Converts the Time Span to a Duration from the `chrono` crate.
    pub fn to_duration(&self) -> Duration {
        self.0
    }

    /// Returns the total amount of seconds (including decimals) this Time Span
    /// represents.
    pub fn total_seconds(&self) -> f64 {
        self.0.num_microseconds().unwrap() as f64 / 1_000_000.0
    }

    /// Returns the total amount of milliseconds (including decimals) this Time
    /// Span represents.
    pub fn total_milliseconds(&self) -> f64 {
        self.0.num_microseconds().unwrap() as f64 / 1_000.0
    }

    /// Parses an optional Time Span from a given textual representation of the
    /// Time Span. If the given text consists entirely of whitespace or is
    /// empty, `None` is returned.
    pub fn parse_opt<S>(text: S) -> Result<Option<TimeSpan>, ParseError>
    where
        S: AsRef<str>,
    {
        let text = text.as_ref();
        if text.trim().is_empty() {
            Ok(None)
        } else {
            Ok(Some(text.parse()?))
        }
    }
}

quick_error! {
    /// The Error type for Time Spans that couldn't be parsed.
    #[derive(Debug)]
    pub enum ParseError {
        /// Couldn't parse as a floating point number.
        Float(err: ParseFloatError) {
            from()
        }
    }
}

impl FromStr for TimeSpan {
    type Err = ParseError;

    fn from_str(mut text: &str) -> Result<Self, ParseError> {
        let factor = if text.starts_with('-') {
            text = &text[1..];
            -1.0
        } else if text.starts_with('−') {
            text = &text[3..];
            -1.0
        } else {
            1.0
        };

        let mut seconds = 0.0;
        for split in text.split(':') {
            seconds = 60.0 * seconds + split.parse::<f64>()?;
        }

        Ok(TimeSpan::from_seconds(factor * seconds))
    }
}

impl Default for TimeSpan {
    fn default() -> Self {
        TimeSpan(Duration::nanoseconds(0))
    }
}

impl From<StdDuration> for TimeSpan {
    fn from(duration: StdDuration) -> Self {
        TimeSpan(Duration::from_std(duration).unwrap())
    }
}

impl AddAssign for TimeSpan {
    fn add_assign(&mut self, rhs: TimeSpan) {
        self.0 = self.0 + rhs.0;
    }
}

impl SubAssign for TimeSpan {
    fn sub_assign(&mut self, rhs: TimeSpan) {
        self.0 = self.0 - rhs.0;
    }
}

use serde::de::{self, Deserialize, Deserializer, Visitor};
use std::fmt;

impl<'de> Deserialize<'de> for TimeSpan {
    fn deserialize<D>(deserializer: D) -> Result<TimeSpan, D::Error>
    where
        D: Deserializer<'de>,
    {
        deserializer.deserialize_str(TimeSpanVisitor)
    }
}

struct TimeSpanVisitor;

impl<'de> Visitor<'de> for TimeSpanVisitor {
    type Value = TimeSpan;

    fn expecting(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result {
        formatter.write_str("a string containing a time")
    }

    fn visit_str<E>(self, v: &str) -> Result<Self::Value, E>
    where
        E: de::Error,
    {
        v.parse()
            .map_err(|_| E::custom(format!("Not a valid time string: {:?}", v)))
    }
}