1import { createLocal } from '../create/local';
2import { cloneWithOffset } from '../units/offset';
3import isFunction from '../utils/is-function';
4import { hooks } from '../utils/hooks';
5import { isMomentInput } from '../utils/is-moment-input';
6import isCalendarSpec from '../utils/is-calendar-spec';
7
8export function getCalendarFormat(myMoment, now) {
9    var diff = myMoment.diff(now, 'days', true);
10    return diff < -6
11        ? 'sameElse'
12        : diff < -1
13        ? 'lastWeek'
14        : diff < 0
15        ? 'lastDay'
16        : diff < 1
17        ? 'sameDay'
18        : diff < 2
19        ? 'nextDay'
20        : diff < 7
21        ? 'nextWeek'
22        : 'sameElse';
23}
24
25export function calendar(time, formats) {
26    // Support for single parameter, formats only overload to the calendar function
27    if (arguments.length === 1) {
28        if (!arguments[0]) {
29            time = undefined;
30            formats = undefined;
31        } else if (isMomentInput(arguments[0])) {
32            time = arguments[0];
33            formats = undefined;
34        } else if (isCalendarSpec(arguments[0])) {
35            formats = arguments[0];
36            time = undefined;
37        }
38    }
39    // We want to compare the start of today, vs this.
40    // Getting start-of-today depends on whether we're local/utc/offset or not.
41    var now = time || createLocal(),
42        sod = cloneWithOffset(now, this).startOf('day'),
43        format = hooks.calendarFormat(this, sod) || 'sameElse',
44        output =
45            formats &&
46            (isFunction(formats[format])
47                ? formats[format].call(this, now)
48                : formats[format]);
49
50    return this.format(
51        output || this.localeData().calendar(format, this, createLocal(now))
52    );
53}