aboutsummaryrefslogtreecommitdiff
path: root/src/date.rs
blob: c329ac3bb15620f69bed53a8b5053e67522dec48 (plain)
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
use std::cmp::{Ordering, Ord, PartialEq, PartialOrd};
use std::ops::Add;

use errors::EventError;

use chrono;
use chrono::{TimeZone, Duration, Datelike};
use chrono::offset::Utc;
use chrono_tz::{Tz, UTC};


#[derive(Debug, Copy, Clone, Eq)]
pub enum Date {
    Time(chrono::DateTime<Tz>),
    AllDay(chrono::Date<Tz>),
}


impl Date {
    pub fn new() -> Date {
        Date::Time(UTC.timestamp(0, 0))
    }


    pub fn now() -> Date {
        Date::Time(UTC.from_utc_datetime(&Utc::now().naive_utc()))
    }

    pub fn parse(date_str: &str, time_zone: &str) -> Result<Self, EventError> {
        let absolute_time = date_str.chars().rev().next().unwrap() == 'Z';
        let tz: Tz = if absolute_time {
            UTC
        } else {
            // FIXME: this should not be UTC but local timezone
            time_zone.parse().unwrap_or(UTC)
        };

        let date = match date_str.find("T") {
            Some(_) => {
                let date_pattern = if absolute_time {
                    "%Y%m%dT%H%M%SZ"
                } else {
                    "%Y%m%dT%H%M%S"
                };
                let time = tz.datetime_from_str(&date_str, date_pattern).unwrap_or(
                    UTC.timestamp(
                        0,
                        0,
                    ),
                );
                Date::Time(time)
            }
            None => {
                Date::AllDay(tz.ymd(
                    date_str[0..4].parse()?,
                    date_str[4..6].parse()?,
                    date_str[6..8].parse()?,
                ))
            }
        };
        Ok(date)
    }

    pub fn month(&self) -> u32 {
        match *self {
            Date::Time(t) => t.month(),
            Date::AllDay(d) => d.month(),
        }
    }

    pub fn with_month(&self, month: u32) -> Option<Date> {
        Some(match *self {
            Date::Time(t) => Date::Time(t.with_month(month)?),
            Date::AllDay(d) => Date::AllDay(d.with_month(month)?),
        })
    }

    pub fn year(&self) -> i32 {
        match *self {
            Date::Time(t) => t.year(),
            Date::AllDay(d) => d.year(),
        }
    }

    pub fn with_year(&self, year: i32) -> Option<Date> {
        Some(match *self {
            Date::Time(t) => Date::Time(t.with_year(year)?),
            Date::AllDay(d) => Date::AllDay(d.with_year(year)?),
        })
    }
}

impl Ord for Date {
    fn cmp(&self, other: &Self) -> Ordering {
        match *self {
            Date::Time(t1) => {
                match *other {
                    Date::Time(t2) => t1.cmp(&t2),
                    Date::AllDay(d) => cmp_date_time(&d, &t1).reverse(),
                }
            }
            Date::AllDay(d1) => {
                match *other {
                    Date::Time(t) => cmp_date_time(&d1, &t),
                    Date::AllDay(d2) => d1.cmp(&d2),
                }
            }
        }
    }
}

impl PartialOrd for Date {
    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
        Some(self.cmp(other))
    }
}

impl PartialEq for Date {
    fn eq(&self, other: &Self) -> bool {
        self.cmp(other) == Ordering::Equal
    }
}

impl Add<Duration> for Date {
    type Output = Date;

    fn add(self, other: Duration) -> Date {
        match self {
            Date::Time(d) => Date::Time(d + other),
            Date::AllDay(d) => Date::AllDay(d + other),
        }
    }
}

fn cmp_date_time<T: TimeZone>(date: &chrono::Date<T>, time: &chrono::DateTime<T>) -> Ordering {
    let d2 = time.date();
    if date.eq(&d2) {
        return Ordering::Less;
    }
    date.cmp(&d2)
}

#[cfg(test)]
mod tests {
    use super::Date;
    use chrono::Datelike;
    use chrono::Timelike;

    #[test]
    fn date_parse_time() {
        match Date::parse("19361020T120000", "").unwrap() {
            Date::Time(time) => {
                assert_eq!(time.year(), 1936);
                assert_eq!(time.hour(), 12);
                assert_eq!(time.day(), 20);
            }
            _ => assert!(true),
        }
    }
}