1 import { Pipe, PipeTransform } from '@angular/core'
2 import { I18n } from '@ngx-translate/i18n-polyfill'
3 import { findIndex } from 'lodash-es'
5 // Thanks: https://stackoverflow.com/questions/3177836/how-to-format-time-since-xxx-e-g-4-minutes-ago-similar-to-stack-exchange-site
6 @Pipe({ name: 'myFromNow' })
7 export class FromNowPipe implements PipeTransform {
9 constructor (private i18n: I18n) { }
11 transform (arg: number | Date | string, short = true) {
12 const argDate = new Date(arg)
13 const seconds = Math.floor((Date.now() - argDate.getTime()) / 1000)
16 unit: 31536000, // 1 year
17 singular: (i: number) => this.i18n('{{i}} year', { i }),
18 plural: (i: number) => this.i18n('{{i}} years', { i })
21 unit: 2592000, // 1 month
23 singular: (i: number) => this.i18n('{{i}} month', { i }),
24 plural: (i: number) => this.i18n('{{i}} months', { i })
27 unit: 604800, // 1 week
29 singular: (i: number) => this.i18n('{{i}} week', { i }),
30 plural: (i: number) => this.i18n('{{i}} weeks', { i })
35 singular: (i: number) => this.i18n('{{i}} day', { i }),
36 plural: (i: number) => this.i18n('{{i}} days', { i })
41 singular: (i: number) => this.i18n('{{i}} hour', { i }),
42 plural: (i: number) => this.i18n('{{i}} hours', { i })
47 singular: (i: number) => this.i18n('{{i}} min', { i }),
48 plural: (i: number) => this.i18n('{{i}} min', { i })
51 // compute the number of units each unit of time has, store it in "interval"
54 interval: Math.floor(seconds / i.unit)
56 // compute the number of units each unit of time has, from the remainder of the previous bigger unit, store it in "interval"
57 .map((i, index, array) => ({
61 : Math.floor((seconds - array[index - 1].interval * array[index - 1].unit) / i.unit)
63 // compute the final string from the "interval", cap it to the max value for the time unit
66 value: (i.interval > 1 ? i.plural : i.singular)(Math.min(i.max, i.interval))
69 // only keep the first two intervals with enough seconds to be considered
70 const big_interval_index = findIndex(intervals, i => i.interval >= 1)
72 .slice(big_interval_index, big_interval_index + 2)
73 .filter(i => i.interval >= 1)
75 if (intervals.length === 0) {
76 return this.i18n('just now')
79 return intervals.length === 1 || short
80 ? this.i18n('{{interval}} ago', { interval: intervals[0].value })
81 : this.i18n('{{big_interval}} {{small_interval}} ago', {
82 big_interval: intervals[0].value,
83 small_interval: intervals[1].value