Display and Formatting

/**
 * Format the moment according to the given format string
 * @param format - Format string using tokens (defaults to ISO 8601)
 * @returns Formatted date string
 */
format(format?: string): string;

/**
 * Get string representation (same as format() with no arguments)
 * @returns ISO 8601 formatted string
 */
toString(): string;

/**
 * Get ISO 8601 string representation
 * @param keepOffset - Whether to keep the current UTC offset (default: false)
 * @returns ISO 8601 formatted string
 */
toISOString(keepOffset?: boolean): string;

/**
 * Get JSON representation (same as toISOString())
 * @returns ISO 8601 formatted string for JSON serialization
 */
toJSON(): string;

/**
 * Get debug representation for console.log and debugging
 * @returns String representation for debugging
 */
inspect(): string;

import moment from "moment";

const date = moment("2023-12-25T15:30:45.123Z");

// Basic formatting
console.log(date.format()); // "2023-12-25T15:30:45Z" (default ISO 8601)
console.log(date.toString()); // Same as format()

// Custom formats
console.log(date.format("YYYY-MM-DD")); // "2023-12-25"
console.log(date.format("MMMM Do, YYYY")); // "December 25th, 2023"
console.log(date.format("dddd, MMMM DD, YYYY h:mm A")); // "Monday, December 25, 2023 3:30 PM"
console.log(date.format("DD/MM/YYYY HH:mm:ss")); // "25/12/2023 15:30:45"

// ISO string formatting
console.log(date.toISOString()); // "2023-12-25T15:30:45.123Z"
console.log(date.toISOString(true)); // Keeps offset if not UTC

// JSON serialization
console.log(JSON.stringify({ date })); // {"date":"2023-12-25T15:30:45.123Z"}

/**
 * Get relative time from now
 * @param withoutSuffix - Remove "ago" or "in" suffix (default: false)
 * @returns Relative time string like "2 hours ago" or "in 3 days"
 */
fromNow(withoutSuffix?: boolean): string;

/**
 * Get relative time to now (opposite of fromNow)
 * @param withoutPrefix - Remove "in" or "ago" prefix (default: false)
 * @returns Relative time string
 */
toNow(withoutPrefix?: boolean): string;

/**
 * Get relative time from another moment
 * @param inp - Reference moment to compare against
 * @param suffix - Include "ago" or "in" suffix (default: true)
 * @returns Relative time string
 */
from(inp: MomentInput, suffix?: boolean): string;

/**
 * Get relative time to another moment (opposite of from)
 * @param inp - Reference moment to compare against
 * @param suffix - Include "ago" or "in" suffix (default: true)
 * @returns Relative time string
 */
to(inp: MomentInput, suffix?: boolean): string;

import moment from "moment";

const now = moment();
const past = moment().subtract(2, "hours");
const future = moment().add(3, "days");

// Relative to now
console.log(past.fromNow()); // "2 hours ago"
console.log(past.fromNow(true)); // "2 hours" (without suffix)
console.log(future.fromNow()); // "in 3 days"

console.log(past.toNow()); // "in 2 hours"
console.log(future.toNow()); // "3 days ago"

// Relative to specific moment
const reference = moment("2023-12-25");
const target = moment("2023-12-28");
console.log(target.from(reference)); // "in 3 days"
console.log(target.to(reference)); // "3 days ago"
console.log(target.from(reference, false)); // "3 days" (without suffix)

/**
 * Get calendar time representation (relative to current week)
 * @returns Calendar string like "Today at 2:30 PM", "Last Monday at 2:30 PM"
 */
calendar(): string;

/**
 * Get calendar time with custom format specification
 * @param formats - Custom calendar format object
 * @returns Formatted calendar string
 */
calendar(formats: CalendarSpec): string;

/**
 * Get calendar time relative to specific reference time
 * @param time - Reference time to compare against (defaults to now)
 * @param formats - Optional custom format specification
 * @returns Formatted calendar string
 */
calendar(time: MomentInput, formats?: CalendarSpec): string;

interface CalendarSpec {
  sameDay?: CalendarSpecVal;     // Today
  nextDay?: CalendarSpecVal;     // Tomorrow
  lastDay?: CalendarSpecVal;     // Yesterday
  nextWeek?: CalendarSpecVal;    // Next week
  lastWeek?: CalendarSpecVal;    // Last week
  sameElse?: CalendarSpecVal;    // Everything else
  [x: string]: CalendarSpecVal | void; // Custom keys
}

type CalendarSpecVal = string | ((m?: MomentInput, now?: Moment) => string);

import moment from "moment";

const now = moment();
const today = moment().hour(14).minute(30);
const yesterday = moment().subtract(1, "day").hour(10);
const tomorrow = moment().add(1, "day").hour(16);
const lastWeek = moment().subtract(7, "days");
const nextMonth = moment().add(1, "month");

// Default calendar formatting
console.log(today.calendar()); // "Today at 2:30 PM"
console.log(yesterday.calendar()); // "Yesterday at 10:00 AM"
console.log(tomorrow.calendar()); // "Tomorrow at 4:00 PM"
console.log(lastWeek.calendar()); // "Last Monday at 2:30 PM"
console.log(nextMonth.calendar()); // "01/25/2024"

// Custom calendar formats
const customFormats = {
  sameDay: "[Today] HH:mm",
  nextDay: "[Tomorrow] HH:mm", 
  lastDay: "[Yesterday] HH:mm",
  nextWeek: "dddd [at] HH:mm",
  lastWeek: "[Last] dddd [at] HH:mm",
  sameElse: "DD/MM/YYYY"
};

console.log(today.calendar(customFormats)); // "Today 14:30"
console.log(yesterday.calendar(customFormats)); // "Yesterday 10:00"

// Calendar relative to specific time
const reference = moment("2023-12-25T12:00:00");
const target = moment("2023-12-25T15:30:00");
console.log(target.calendar(reference)); // "Today at 3:30 PM"

/**
 * Get Unix timestamp in milliseconds (same as +moment or moment.getTime())
 * @returns Milliseconds since Unix epoch
 */
valueOf(): number;

/**
 * Get Unix timestamp in seconds (not milliseconds)
 * @returns Seconds since Unix epoch
 */
unix(): number;

/**
 * Convert to native JavaScript Date object
 * @returns Native Date object
 */
toDate(): Date;

/**
 * Convert to array of date components
 * @returns Array of [year, month, day, hour, minute, second, millisecond]
 */
toArray(): number[];

/**
 * Convert to object with date components
 * @returns Object with date/time properties
 */
toObject(): MomentObjectOutput;

interface MomentObjectOutput {
  years: number;
  months: number;      // 0-indexed (0 = January)
  date: number;        // Day of month
  hours: number;
  minutes: number;
  seconds: number;
  milliseconds: number;
}

import moment from "moment";

const date = moment("2023-12-25T15:30:45.123Z");

// Numeric representations
console.log(date.valueOf()); // 1703517045123 (milliseconds)
console.log(+date); // Same as valueOf()
console.log(date.unix()); // 1703517045 (seconds)

// Conversions
console.log(date.toDate()); // Native Date object
console.log(date.toArray()); // [2023, 11, 25, 15, 30, 45, 123]

const obj = date.toObject();
console.log(obj);
// {
//   years: 2023,
//   months: 11,    // December (0-indexed)
//   date: 25,
//   hours: 15,
//   minutes: 30,
//   seconds: 45,
//   milliseconds: 123
// }

/**
 * Get or set locale for this moment instance
 * @param locale - Locale identifier (when setting)
 * @returns Current locale string (when getting) or this moment (when setting)
 */
locale(): string;
locale(locale: LocaleSpecifier): Moment;

/**
 * Get locale data object for this moment's locale
 * @returns Locale data object with formatting functions and display names
 */
localeData(): Locale;

type LocaleSpecifier = string | Moment | Duration | string[] | boolean;

import moment from "moment";

const date = moment("2023-12-25T15:30:00");

// Default locale formatting
console.log(date.format("LLLL")); // "Monday, December 25, 2023 3:30 PM"
console.log(date.format("dddd, MMMM Do YYYY")); // "Monday, December 25th 2023"

// Set locale for instance
const frenchDate = date.clone().locale("fr");
console.log(frenchDate.format("LLLL")); // "lundi 25 décembre 2023 15:30"
console.log(frenchDate.format("dddd, MMMM Do YYYY")); // "lundi, décembre 25e 2023"

// Multiple locales
const germanDate = date.clone().locale("de");
console.log(germanDate.format("LLLL")); // "Montag, 25. Dezember 2023 15:30"

// Get current locale
console.log(date.locale()); // "en"
console.log(frenchDate.locale()); // "fr"

// Locale data
const localeData = frenchDate.localeData();
console.log(localeData.months()); // French month names array

// Year
YYYY    // 2023
YY      // 23

// Month
MM      // 01-12
MMM     // Jan, Feb, ..., Dec
MMMM    // January, February, ..., December
M       // 1-12

// Day of Month
DD      // 01-31
Do      // 1st, 2nd, 3rd, ..., 31st
D       // 1-31

// Day of Year
DDDD    // 001-365
DDD     // 1-365

// Day of Week
dddd    // Monday, Tuesday, ..., Sunday
ddd     // Mon, Tue, ..., Sun
dd      // Mo, Tu, ..., Su
d       // 0-6 (Sunday = 0)
e       // 0-6 (locale aware)
E       // 1-7 (ISO, Monday = 1)

// Hour
HH      // 00-23
H       // 0-23
hh      // 01-12
h       // 1-12
kk      // 01-24
k       // 1-24

// Minute
mm      // 00-59
m       // 0-59

// Second
ss      // 00-59
s       // 0-59

// Fractional Second
SSS     // 000-999 (3 digits)
SS      // 00-99 (2 digits)
S       // 0-9 (1 digit)

// AM/PM
A       // AM, PM
a       // am, pm

// Timezone
Z       // +05:00, -08:00
ZZ      // +0500, -0800

// Week of Year
ww      // 01-53 (locale aware)
w       // 1-53 (locale aware)
WW      // 01-53 (ISO week)
W       // 1-53 (ISO week)

// Week Year
gggg    // Week year (locale aware)
gg      // 2-digit week year (locale aware)
GGGG    // ISO week year
GG      // 2-digit ISO week year

// Locale-aware formatting (requires locale to be set)
LTS     // 8:30:25 PM
LT      // 8:30 PM
L       // 09/04/1986
LL      // September 4, 1986 
LLL     // September 4, 1986 8:30 PM
LLLL    // Monday, September 4, 1986 8:30 PM

// Lowercase versions
lts     // 8:30:25 pm
lt      // 8:30 pm
l       // 9/4/1986
ll      // Sep 4, 1986
lll     // Sep 4, 1986 8:30 pm
llll    // Mon, Sep 4, 1986 8:30 pm

// Escape characters in square brackets
"[Today is] dddd"     // "Today is Monday"
"YYYY [escaped] YYYY" // "2023 escaped 2023"
"[Quarter] Q, YYYY"   // "Quarter 4, 2023"

import moment from "moment";

const date = moment("2023-12-25T15:30:45.123");

// Common formats
console.log(date.format("YYYY-MM-DD")); // "2023-12-25"
console.log(date.format("MM/DD/YYYY")); // "12/25/2023"
console.log(date.format("DD-MMM-YYYY")); // "25-Dec-2023"
console.log(date.format("dddd, MMMM Do, YYYY")); // "Monday, December 25th, 2023"

// Time formats
console.log(date.format("HH:mm:ss")); // "15:30:45"
console.log(date.format("h:mm A")); // "3:30 PM"
console.log(date.format("hh:mm:ss A")); // "03:30:45 PM"

// Combined formats
console.log(date.format("YYYY-MM-DD HH:mm:ss")); // "2023-12-25 15:30:45"
console.log(date.format("ddd, MMM Do YYYY, h:mm A")); // "Mon, Dec 25th 2023, 3:30 PM"

// With literals
console.log(date.format("[Today is] dddd [the] Do [of] MMMM"));
// "Today is Monday the 25th of December"