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DavidWells/parse-time-string.js

Created February 18, 2022 22:54
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Parse time out of random string. Handy
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parse-time-string.js
// https://github.com/substack/parse-messy-time/blob/master/index.js
var months = [
'January', 'February', 'March', 'April', 'May', 'June', 'July', 'August',
'September', 'October', 'November', 'December'
];
var days = [
'Sunday', 'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday'
];
var hmsre = RegExp(
'(\\d+\\.?\\d*(?:[:h]\\d+\\.?\\d*(?:[:m]\\d+\\.\\d*s?)?)?)'
);
var tokre = RegExp(
'\\s+|(\\d+(?:st|th|nd|rd|th))\\b'
+ '|' + hmsre.source + '([A-Za-z]+)'
+ '|([A-Za-z]+)' + hmsre.source
);
module.exports = function (str, opts) {
if (!opts) opts = {};
var now = opts.now || new Date;
if (typeof now === 'number' || typeof now === 'string') now = new Date(now);
var ago = false;
var tokens = str.split(tokre).filter(Boolean).map(lc);
var res = {};
for (var i = 0; i < tokens.length; i++) {
var t = tokens[i];
var next = tokens[i+1];
var prev = tokens[i-1];
var m;
if (m = /(\d+)(st|nd|rd|th)/i.exec(t)) {
if (next === 'of') {
next = tokens[i+2];
i++;
}
res.date = Number(m[1]);
if (monthish(next)) {
res.month = next;
i++;
}
}
else if ((m = /(\d+)(st|nd|rd|th)?/i.exec(next))
&& monthish(t)) {
res.month = t;
res.date = Number(m[1]);
i++;
if (/^\d+$/.test(tokens[i+1])) { // year
res.year = Number(tokens[i+1]);
i++;
}
}
else if ((m = hmsre.exec(t)) && isunit(next)) {
if (tokens[i-1] === 'in') {
for (var j = i; j < tokens.length; j += 2) {
if (tokens[j] === 'and') j --;
else if ((m = hmsre.exec(tokens[j]))
&& ishunit(tokens[j+1])) {
addu(parseh(tokens[j]), nunit(tokens[j+1]));
}
else if ((m = /^(\d+\.?\d*)/.exec(tokens[j]))
&& isdunit(tokens[j+1])) {
daddu(Number(m[1]), nunit(tokens[j+1]));
}
else break;
}
i = j;
}
else {
for (var j = i + 2; j < tokens.length; j++) {
if (tokens[j] === 'ago') {
ago = true;
break;
}
}
if (j === tokens.length) continue;
for (var k = i; k < j; k++) {
if ((m = hmsre.exec(tokens[k])) && ishunit(tokens[k+1])) {
subu(parseh(tokens[k]), nunit(tokens[k+1]));
}
else if ((m = /^(\d+\.?\d*)/.exec(tokens[k]))
&& isdunit(tokens[k+1])) {
dsubu(Number(m[1]), nunit(tokens[k+1]));
}
}
i = j;
}
}
else if (/noon/.test(t)) {
res.hours = 12
res.minutes = 0
res.seconds = 0
}
else if (/midnight/.test(t)) {
res.hours = 0
res.minutes = 0
res.seconds = 0
}
else if (/\d+[:h]\d+/.test(t) || /^(am|pm)/.test(next)) {
var hms = parseh(t, next);
if (hms[0] !== null) res.hours = hms[0];
if (hms[1] !== null) res.minutes = hms[1];
if (hms[2] !== null) res.seconds = hms[2];
}
else if ((m = /^(\d+)/.exec(t)) && monthish(next)) {
var x = Number(m[1]);
if (res.year === undefined && x > 31) res.year = x;
else if (res.date === undefined) res.date = x;
if (res.month === undefined) res.month = next;
i++;
}
else if (monthish(t) && (m = /^(\d+)/.exec(next))) {
var x = Number(m[1]);
if (res.year === undefined && x > 31) res.year = x;
else if (res.date === undefined) res.date = x;
if (res.month === undefined) res.month = t;
i++;
}
else if ((m = /^(\d+)/.exec(t)) && monthish(prev)) {
var x = Number(m[1]);
if (res.year === undefined) res.year = x;
else if (res.hours === undefined) res.hours = x;
}
else if (m = /^[`'\u00b4\u2019](\d+)/.exec(t)) {
res.year = Number(m[1]);
}
else if (/^\d{4}[\W_]\d{1,2}[\W_]\d{1,2}/.test(t)) {
var yms = t.split(/[\W_]/);
res.year = Number(yms[0]);
res.month = Number(yms[1]) - 1;
res.date = Number(yms[2]);
}
else if (m = /^(\d+)/.exec(t)) {
var x = Number(m[1]);
if (res.hours === undefined && x < 24) res.hours = x;
else if (res.date === undefined && x <= 31) res.date = x;
else if (res.year === undefined && x > 31) res.year = x;
else if (res.year == undefined
&& res.hours !== undefined && res.date !== undefined) {
res.year = x;
}
else if (res.hours === undefined
&& res.date !== undefined && res.year !== undefined) {
res.hours = x;
}
else if (res.date === undefined
&& res.hours !== undefined && res.year !== undefined) {
res.date = x;
}
}
else if (/^today$/.test(t) && res.date === undefined) {
res.date = now.getDate();
res.month = months[now.getMonth()];
res.year = now.getFullYear();
}
else if (/^now$/.test(t) && res.date === undefined) {
res.hours = now.getHours();
res.minutes = now.getMinutes();
res.seconds = now.getSeconds();
res.date = now.getDate();
res.month = months[now.getMonth()];
res.year = now.getFullYear();
}
else if (/^to?m+o?r+o?w?/.test(t) && res.date === undefined) {
var tomorrow = new Date(now.valueOf() + 24*60*60*1000);
res.date = tomorrow.getDate();
if (res.month === undefined) {
res.month = months[tomorrow.getMonth()];
}
if (res.year === undefined) {
res.year = tomorrow.getFullYear();
}
}
else if (/^yesterday/.test(t) && res.date === undefined) {
var yst = new Date(now.valueOf() - 24*60*60*1000);
res.date = yst.getDate();
if (res.month === undefined) {
res.month = months[yst.getMonth()];
}
if (res.year === undefined) {
res.year = yst.getFullYear();
}
}
else if (t === 'next' && dayish(next) && res.date === undefined) {
setFromDay(next, 7);
i++;
}
else if (t === 'last' && dayish(next) && res.date === undefined) {
setFromDay(next, -7);
i++;
}
else if (dayish(t) && res.date === undefined) {
setFromDay(t, 0);
}
}
if (res.year < 100) {
var y = now.getFullYear();
var py = y % 100;
if (py + 10 < res.year) {
res.year += y - py - 100;
}
else res.year += y - py;
}
if (res.month && typeof res.month !== 'number') {
res.month = nmonth(res.month);
}
var out = new Date(now);
out.setHours(res.hours === undefined ? 0 : res.hours);
out.setMinutes(res.minutes === undefined ? 0 : res.minutes);
out.setSeconds(res.seconds === undefined ? 0 : res.seconds);
var monthSet = res.month;
if (typeof res.month === 'number') {
out.setMonth(res.month)
}
else if (res.month) {
monthSet = months.indexOf(res.month);
out.setMonth(monthSet);
}
if (res.date !== undefined) out.setDate(res.date);
if (monthSet !== undefined && out.getMonth() !== monthSet) {
out.setMonth(monthSet);
}
if (res.year) out.setYear(res.year);
else if (out < now && !ago
&& (Math.abs(out.getMonth()+12 -now.getMonth()) % 12) >= 1) {
out.setYear(now.getFullYear() + 1);
}
return out;
function setFromDay (t, x) {
var dayi = days.indexOf(nday(t));
var xdays = (7 + dayi - now.getDay()) % 7 + x;
var d = new Date(now.valueOf() + xdays*24*60*60*1000);
res.date = d.getDate();
if (res.month === undefined) {
res.month = months[d.getMonth()];
}
if (res.year === undefined) {
res.year = d.getFullYear();
}
}
function opu (hms, u, op) {
if (u == 'hours') {
res.hours = op(now.getHours(), hms[0]);
res.minutes = op(now.getMinutes(), hms[1] === null ? 0 : hms[1]);
res.seconds = op(now.getSeconds(), hms[2] === null ? 0 : hms[2]);
}
else if (u == 'minutes') {
if (res.hours === undefined) res.hours = now.getHours();
res.minutes = op(now.getMinutes(), hms[0] === null ? 0 : hms[0]);
res.seconds = op(now.getSeconds(), hms[1] === null ? 0 : hms[1]);
}
else if (u == 'seconds') {
if (res.hours === undefined) res.hours = now.getHours();
if (res.minutes === undefined) res.minutes = now.getMinutes();
res.seconds = op(now.getSeconds(), hms[0] === null ? 0 : hms[0]);
}
}
function subu (hms, u) { opu(hms, u, sub) }
function addu (hms, u) { opu(hms, u, add) }
function dopu (n, u, op) {
if (res.hours === undefined) res.hours = now.getHours();
if (res.minutes === undefined) res.minutes = now.getMinutes();
if (res.seconds === undefined) res.seconds = now.getSeconds();
if (u === 'days') {
res.date = op(now.getDate(), n);
}
else if (u === 'weeks') {
res.date = op(now.getDate(), n*7);
}
else if (u === 'months') {
res.month = op(now.getMonth(), n);
}
else if (u === 'years') {
res.year = op(now.getFullYear(), n);
}
}
function dsubu (n, u) { dopu(n, u, sub) }
function daddu (n, u) { dopu(n, u, add) }
};
function add (a, b) { return a + b }
function sub (a, b) { return a - b }
function lc (s) { return String(s).toLowerCase() }
function ishunit (s) {
var n = nunit(s);
return n === 'hours' || n === 'minutes' || n === 'seconds';
}
function isdunit (s) {
var n = nunit(s);
return n === 'days' || n === 'weeks' || n === 'months' || n === 'years';
}
function isunit (s) { return Boolean(nunit(s)) }
function nunit (s) {
if (/^(ms|millisecs?|milliseconds?)$/.test(s)) return 'milliseconds';
if (/^(s|secs?|seconds?)$/.test(s)) return 'seconds';
if (/^(m|mins?|minutes?)$/.test(s)) return 'minutes';
if (/^(h|hrs?|hours?)$/.test(s)) return 'hours';
if (/^(d|days?)$/.test(s)) return 'days';
if (/^(w|wks?|weeks?)$/.test(s)) return 'weeks';
if (/^(mo|mnths?|months?)$/.test(s)) return 'months';
if (/^(y|yrs?|years?)$/.test(s)) return 'years';
}
function monthish (s) { return Boolean(nmonth(s)) }
function dayish (s) {
return /^(mon|tue|wed|thu|fri|sat|sun)/i.test(s);
}
function nmonth (s) {
if (/^jan/i.test(s)) return 'January';
if (/^feb/i.test(s)) return 'February';
if (/^mar/i.test(s)) return 'March';
if (/^apr/i.test(s)) return 'April';
if (/^may/i.test(s)) return 'May';
if (/^jun/i.test(s)) return 'June';
if (/^jul/i.test(s)) return 'July';
if (/^aug/i.test(s)) return 'August';
if (/^sep/i.test(s)) return 'September';
if (/^oct/i.test(s)) return 'October';
if (/^nov/i.test(s)) return 'November';
if (/^dec/i.test(s)) return 'December';
}
function nday (s) {
if (/^mon/i.test(s)) return 'Monday';
if (/^tue/i.test(s)) return 'Tuesday';
if (/^wed/i.test(s)) return 'Wednesday';
if (/^thu/i.test(s)) return 'Thursday';
if (/^fri/i.test(s)) return 'Friday';
if (/^sat/i.test(s)) return 'Saturday';
if (/^sun/i.test(s)) return 'Sunday';
}
function parseh (s, next) {
var m = /(\d+\.?\d*)(?:[:h](\d+\.?\d*)(?:[:m](\d+\.?\d*s?\.?\d*))?)?/.exec(s);
var hms = [ Number(m[1]), null, null ];
if (/^am/.test(next) && hms[0] == 12) hms[0] -= 12;
if (/^pm/.test(next) && hms[0] < 12) hms[0] += 12;
if (m[2]) hms[1] = Number(m[2]);
if (m[3]) hms[2] = Number(m[3]);
if (hms[0] > floorup(hms[0])) {
hms[1] = floorup((hms[0] - floorup(hms[0])) * 60);
hms[0] = floorup(hms[0]);
}
if (hms[1] > floorup(hms[1])) {
hms[2] = floorup((hms[1] - floorup(hms[1])) * 60);
hms[1] = floorup(hms[1]);
}
return hms;
}
function floorup (x) {
return Math.floor(Math.round(x * 1e6) / 1e6);
}
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