aboutsummaryrefslogtreecommitdiff
path: root/pkg/humanize/times.go
blob: 1bd51669b320a0f01dbbf1f49bf45241e6c58253 (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
// This code includes software originally developed by Dustin Sallings.
//
// Copyright (c) 2005-2008  Dustin Sallings <dustin@spy.net>
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.
//
//<http://www.opensource.org/licenses/mit-license.php>

package humanize

import (
	"fmt"
	"math"
	"sort"
	"time"
)

// Seconds-based time units
const (
	Day      = 24 * time.Hour
	Week     = 7 * Day
	Month    = 30 * Day
	Year     = 12 * Month
	LongTime = 37 * Year
)

// Time formats a time into a relative string.
//
// Time(someT) -> "3 weeks ago"
func Time(then time.Time) string {
	return RelTime(then, time.Now(), "ago", "from now")
}

// A RelTimeMagnitude struct contains a relative time point at which
// the relative format of time will switch to a new format string.  A
// slice of these in ascending order by their "D" field is passed to
// CustomRelTime to format durations.
//
// The Format field is a string that may contain a "%s" which will be
// replaced with the appropriate signed label (e.g. "ago" or "from
// now") and a "%d" that will be replaced by the quantity.
//
// The DivBy field is the amount of time the time difference must be
// divided by in order to display correctly.
//
// e.g. if D is 2*time.Minute and you want to display "%d minutes %s"
// DivBy should be time.Minute so whatever the duration is will be
// expressed in minutes.
type RelTimeMagnitude struct {
	D      time.Duration
	Format string
	DivBy  time.Duration
}

var defaultMagnitudes = []RelTimeMagnitude{
	{time.Second, "now", time.Second},
	{2 * time.Second, "1 second %s", 1},
	{time.Minute, "%d seconds %s", time.Second},
	{2 * time.Minute, "1 minute %s", 1},
	{time.Hour, "%d minutes %s", time.Minute},
	{2 * time.Hour, "1 hour %s", 1},
	{Day, "%d hours %s", time.Hour},
	{2 * Day, "1 day %s", 1},
	{Week, "%d days %s", Day},
	{2 * Week, "1 week %s", 1},
	{Month, "%d weeks %s", Week},
	{2 * Month, "1 month %s", 1},
	{Year, "%d months %s", Month},
	{18 * Month, "1 year %s", 1},
	{2 * Year, "2 years %s", 1},
	{LongTime, "%d years %s", Year},
	{math.MaxInt64, "a long while %s", 1},
}

// RelTime formats a time into a relative string.
//
// It takes two times and two labels.  In addition to the generic time
// delta string (e.g. 5 minutes), the labels are used applied so that
// the label corresponding to the smaller time is applied.
//
// RelTime(timeInPast, timeInFuture, "earlier", "later") -> "3 weeks earlier"
func RelTime(a, b time.Time, albl, blbl string) string {
	return CustomRelTime(a, b, albl, blbl, defaultMagnitudes)
}

// CustomRelTime formats a time into a relative string.
//
// It takes two times two labels and a table of relative time formats.
// In addition to the generic time delta string (e.g. 5 minutes), the
// labels are used applied so that the label corresponding to the
// smaller time is applied.
func CustomRelTime(a, b time.Time, albl, blbl string, magnitudes []RelTimeMagnitude) string {
	lbl := albl
	diff := b.Sub(a)

	if a.After(b) {
		lbl = blbl
		diff = a.Sub(b)
	}

	n := sort.Search(len(magnitudes), func(i int) bool {
		return magnitudes[i].D > diff
	})

	if n >= len(magnitudes) {
		n = len(magnitudes) - 1
	}
	mag := magnitudes[n]
	args := []interface{}{}
	escaped := false
	for _, ch := range mag.Format {
		if escaped {
			switch ch {
			case 's':
				args = append(args, lbl)
			case 'd':
				args = append(args, diff/mag.DivBy)
			}
			escaped = false
		} else {
			escaped = ch == '%'
		}
	}
	return fmt.Sprintf(mag.Format, args...)
}