vis.js is a dynamic, browser-based visualization library
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  1. var moment = require('../module/moment');
  2. var DateUtil = require('./DateUtil');
  3. var util = require('../util');
  4. /**
  5. * @constructor TimeStep
  6. * The class TimeStep is an iterator for dates. You provide a start date and an
  7. * end date. The class itself determines the best scale (step size) based on the
  8. * provided start Date, end Date, and minimumStep.
  9. *
  10. * If minimumStep is provided, the step size is chosen as close as possible
  11. * to the minimumStep but larger than minimumStep. If minimumStep is not
  12. * provided, the scale is set to 1 DAY.
  13. * The minimumStep should correspond with the onscreen size of about 6 characters
  14. *
  15. * Alternatively, you can set a scale by hand.
  16. * After creation, you can initialize the class by executing first(). Then you
  17. * can iterate from the start date to the end date via next(). You can check if
  18. * the end date is reached with the function hasNext(). After each step, you can
  19. * retrieve the current date via getCurrent().
  20. * The TimeStep has scales ranging from milliseconds, seconds, minutes, hours,
  21. * days, to years.
  22. *
  23. * Version: 1.2
  24. *
  25. * @param {Date} [start] The start date, for example new Date(2010, 9, 21)
  26. * or new Date(2010, 9, 21, 23, 45, 00)
  27. * @param {Date} [end] The end date
  28. * @param {Number} [minimumStep] Optional. Minimum step size in milliseconds
  29. */
  30. function TimeStep(start, end, minimumStep, hiddenDates) {
  31. this.moment = moment;
  32. // variables
  33. this.current = this.moment();
  34. this._start = this.moment();
  35. this._end = this.moment();
  36. this.autoScale = true;
  37. this.scale = 'day';
  38. this.step = 1;
  39. // initialize the range
  40. this.setRange(start, end, minimumStep);
  41. // hidden Dates options
  42. this.switchedDay = false;
  43. this.switchedMonth = false;
  44. this.switchedYear = false;
  45. if (Array.isArray(hiddenDates)) {
  46. this.hiddenDates = hiddenDates;
  47. }
  48. else if (hiddenDates != undefined) {
  49. this.hiddenDates = [hiddenDates];
  50. }
  51. else {
  52. this.hiddenDates = [];
  53. }
  54. this.format = TimeStep.FORMAT; // default formatting
  55. }
  56. // Time formatting
  57. TimeStep.FORMAT = {
  58. minorLabels: {
  59. millisecond:'SSS',
  60. second: 's',
  61. minute: 'HH:mm',
  62. hour: 'HH:mm',
  63. weekday: 'ddd D',
  64. day: 'D',
  65. month: 'MMM',
  66. year: 'YYYY'
  67. },
  68. majorLabels: {
  69. millisecond:'HH:mm:ss',
  70. second: 'D MMMM HH:mm',
  71. minute: 'ddd D MMMM',
  72. hour: 'ddd D MMMM',
  73. weekday: 'MMMM YYYY',
  74. day: 'MMMM YYYY',
  75. month: 'YYYY',
  76. year: ''
  77. }
  78. };
  79. /**
  80. * Set custom constructor function for moment. Can be used to set dates
  81. * to UTC or to set a utcOffset.
  82. * @param {function} moment
  83. */
  84. TimeStep.prototype.setMoment = function (moment) {
  85. this.moment = moment;
  86. // update the date properties, can have a new utcOffset
  87. this.current = this.moment(this.current.valueOf());
  88. this._start = this.moment(this._start.valueOf());
  89. this._end = this.moment(this._end.valueOf());
  90. };
  91. /**
  92. * Set custom formatting for the minor an major labels of the TimeStep.
  93. * Both `minorLabels` and `majorLabels` are an Object with properties:
  94. * 'millisecond', 'second', 'minute', 'hour', 'weekday', 'day', 'month', 'year'.
  95. * @param {{minorLabels: Object, majorLabels: Object}} format
  96. */
  97. TimeStep.prototype.setFormat = function (format) {
  98. var defaultFormat = util.deepExtend({}, TimeStep.FORMAT);
  99. this.format = util.deepExtend(defaultFormat, format);
  100. };
  101. /**
  102. * Set a new range
  103. * If minimumStep is provided, the step size is chosen as close as possible
  104. * to the minimumStep but larger than minimumStep. If minimumStep is not
  105. * provided, the scale is set to 1 DAY.
  106. * The minimumStep should correspond with the onscreen size of about 6 characters
  107. * @param {Date} [start] The start date and time.
  108. * @param {Date} [end] The end date and time.
  109. * @param {int} [minimumStep] Optional. Minimum step size in milliseconds
  110. */
  111. TimeStep.prototype.setRange = function(start, end, minimumStep) {
  112. if (!(start instanceof Date) || !(end instanceof Date)) {
  113. throw "No legal start or end date in method setRange";
  114. }
  115. this._start = (start != undefined) ? this.moment(start.valueOf()) : new Date();
  116. this._end = (end != undefined) ? this.moment(end.valueOf()) : new Date();
  117. if (this.autoScale) {
  118. this.setMinimumStep(minimumStep);
  119. }
  120. };
  121. /**
  122. * Set the range iterator to the start date.
  123. */
  124. TimeStep.prototype.start = function() {
  125. this.current = this._start.clone();
  126. this.roundToMinor();
  127. };
  128. /**
  129. * Round the current date to the first minor date value
  130. * This must be executed once when the current date is set to start Date
  131. */
  132. TimeStep.prototype.roundToMinor = function() {
  133. // round to floor
  134. // IMPORTANT: we have no breaks in this switch! (this is no bug)
  135. // noinspection FallThroughInSwitchStatementJS
  136. switch (this.scale) {
  137. case 'year':
  138. this.current.year(this.step * Math.floor(this.current.year() / this.step));
  139. this.current.month(0);
  140. case 'month': this.current.date(1);
  141. case 'day': // intentional fall through
  142. case 'weekday': this.current.hours(0);
  143. case 'hour': this.current.minutes(0);
  144. case 'minute': this.current.seconds(0);
  145. case 'second': this.current.milliseconds(0);
  146. //case 'millisecond': // nothing to do for milliseconds
  147. }
  148. if (this.step != 1) {
  149. // round down to the first minor value that is a multiple of the current step size
  150. switch (this.scale) {
  151. case 'millisecond': this.current.subtract(this.current.milliseconds() % this.step, 'milliseconds'); break;
  152. case 'second': this.current.subtract(this.current.seconds() % this.step, 'seconds'); break;
  153. case 'minute': this.current.subtract(this.current.minutes() % this.step, 'minutes'); break;
  154. case 'hour': this.current.subtract(this.current.hours() % this.step, 'hours'); break;
  155. case 'weekday': // intentional fall through
  156. case 'day': this.current.subtract((this.current.date() - 1) % this.step, 'day'); break;
  157. case 'month': this.current.subtract(this.current.month() % this.step, 'month'); break;
  158. case 'year': this.current.subtract(this.current.year() % this.step, 'year'); break;
  159. default: break;
  160. }
  161. }
  162. };
  163. /**
  164. * Check if the there is a next step
  165. * @return {boolean} true if the current date has not passed the end date
  166. */
  167. TimeStep.prototype.hasNext = function () {
  168. return (this.current.valueOf() <= this._end.valueOf());
  169. };
  170. /**
  171. * Do the next step
  172. */
  173. TimeStep.prototype.next = function() {
  174. var prev = this.current.valueOf();
  175. // Two cases, needed to prevent issues with switching daylight savings
  176. // (end of March and end of October)
  177. if (this.current.month() < 6) {
  178. switch (this.scale) {
  179. case 'millisecond': this.current.add(this.step, 'millisecond'); break;
  180. case 'second': this.current.add(this.step, 'second'); break;
  181. case 'minute': this.current.add(this.step, 'minute'); break;
  182. case 'hour':
  183. this.current.add(this.step, 'hour');
  184. // in case of skipping an hour for daylight savings, adjust the hour again (else you get: 0h 5h 9h ... instead of 0h 4h 8h ...)
  185. // TODO: is this still needed now we use the function of moment.js?
  186. this.current.subtract(this.current.hours() % this.step, 'hour');
  187. break;
  188. case 'weekday': // intentional fall through
  189. case 'day': this.current.add(this.step, 'day'); break;
  190. case 'month': this.current.add(this.step, 'month'); break;
  191. case 'year': this.current.add(this.step, 'year'); break;
  192. default: break;
  193. }
  194. }
  195. else {
  196. switch (this.scale) {
  197. case 'millisecond': this.current.add(this.step, 'millisecond'); break;
  198. case 'second': this.current.add(this.step, 'second'); break;
  199. case 'minute': this.current.add(this.step, 'minute'); break;
  200. case 'hour': this.current.add(this.step, 'hour'); break;
  201. case 'weekday': // intentional fall through
  202. case 'day': this.current.add(this.step, 'day'); break;
  203. case 'month': this.current.add(this.step, 'month'); break;
  204. case 'year': this.current.add(this.step, 'year'); break;
  205. default: break;
  206. }
  207. }
  208. if (this.step != 1) {
  209. // round down to the correct major value
  210. switch (this.scale) {
  211. case 'millisecond': if(this.current.milliseconds() < this.step) this.current.milliseconds(0); break;
  212. case 'second': if(this.current.seconds() < this.step) this.current.seconds(0); break;
  213. case 'minute': if(this.current.minutes() < this.step) this.current.minutes(0); break;
  214. case 'hour': if(this.current.hours() < this.step) this.current.hours(0); break;
  215. case 'weekday': // intentional fall through
  216. case 'day': if(this.current.date() < this.step+1) this.current.date(1); break;
  217. case 'month': if(this.current.month() < this.step) this.current.month(0); break;
  218. case 'year': break; // nothing to do for year
  219. default: break;
  220. }
  221. }
  222. // safety mechanism: if current time is still unchanged, move to the end
  223. if (this.current.valueOf() == prev) {
  224. this.current = this._end.clone();
  225. }
  226. // Reset switches for year, month and day. Will get set to true where appropriate in DateUtil.stepOverHiddenDates
  227. this.switchedDay = false;
  228. this.switchedMonth = false;
  229. this.switchedYear = false;
  230. DateUtil.stepOverHiddenDates(this.moment, this, prev);
  231. };
  232. /**
  233. * Get the current datetime
  234. * @return {Moment} current The current date
  235. */
  236. TimeStep.prototype.getCurrent = function() {
  237. return this.current;
  238. };
  239. /**
  240. * Set a custom scale. Autoscaling will be disabled.
  241. * For example setScale('minute', 5) will result
  242. * in minor steps of 5 minutes, and major steps of an hour.
  243. *
  244. * @param {{scale: string, step: number}} params
  245. * An object containing two properties:
  246. * - A string 'scale'. Choose from 'millisecond', 'second',
  247. * 'minute', 'hour', 'weekday', 'day', 'month', 'year'.
  248. * - A number 'step'. A step size, by default 1.
  249. * Choose for example 1, 2, 5, or 10.
  250. */
  251. TimeStep.prototype.setScale = function(params) {
  252. if (params && typeof params.scale == 'string') {
  253. this.scale = params.scale;
  254. this.step = params.step > 0 ? params.step : 1;
  255. this.autoScale = false;
  256. }
  257. };
  258. /**
  259. * Enable or disable autoscaling
  260. * @param {boolean} enable If true, autoascaling is set true
  261. */
  262. TimeStep.prototype.setAutoScale = function (enable) {
  263. this.autoScale = enable;
  264. };
  265. /**
  266. * Automatically determine the scale that bests fits the provided minimum step
  267. * @param {Number} [minimumStep] The minimum step size in milliseconds
  268. */
  269. TimeStep.prototype.setMinimumStep = function(minimumStep) {
  270. if (minimumStep == undefined) {
  271. return;
  272. }
  273. //var b = asc + ds;
  274. var stepYear = (1000 * 60 * 60 * 24 * 30 * 12);
  275. var stepMonth = (1000 * 60 * 60 * 24 * 30);
  276. var stepDay = (1000 * 60 * 60 * 24);
  277. var stepHour = (1000 * 60 * 60);
  278. var stepMinute = (1000 * 60);
  279. var stepSecond = (1000);
  280. var stepMillisecond= (1);
  281. // find the smallest step that is larger than the provided minimumStep
  282. if (stepYear*1000 > minimumStep) {this.scale = 'year'; this.step = 1000;}
  283. if (stepYear*500 > minimumStep) {this.scale = 'year'; this.step = 500;}
  284. if (stepYear*100 > minimumStep) {this.scale = 'year'; this.step = 100;}
  285. if (stepYear*50 > minimumStep) {this.scale = 'year'; this.step = 50;}
  286. if (stepYear*10 > minimumStep) {this.scale = 'year'; this.step = 10;}
  287. if (stepYear*5 > minimumStep) {this.scale = 'year'; this.step = 5;}
  288. if (stepYear > minimumStep) {this.scale = 'year'; this.step = 1;}
  289. if (stepMonth*3 > minimumStep) {this.scale = 'month'; this.step = 3;}
  290. if (stepMonth > minimumStep) {this.scale = 'month'; this.step = 1;}
  291. if (stepDay*5 > minimumStep) {this.scale = 'day'; this.step = 5;}
  292. if (stepDay*2 > minimumStep) {this.scale = 'day'; this.step = 2;}
  293. if (stepDay > minimumStep) {this.scale = 'day'; this.step = 1;}
  294. if (stepDay/2 > minimumStep) {this.scale = 'weekday'; this.step = 1;}
  295. if (stepHour*4 > minimumStep) {this.scale = 'hour'; this.step = 4;}
  296. if (stepHour > minimumStep) {this.scale = 'hour'; this.step = 1;}
  297. if (stepMinute*15 > minimumStep) {this.scale = 'minute'; this.step = 15;}
  298. if (stepMinute*10 > minimumStep) {this.scale = 'minute'; this.step = 10;}
  299. if (stepMinute*5 > minimumStep) {this.scale = 'minute'; this.step = 5;}
  300. if (stepMinute > minimumStep) {this.scale = 'minute'; this.step = 1;}
  301. if (stepSecond*15 > minimumStep) {this.scale = 'second'; this.step = 15;}
  302. if (stepSecond*10 > minimumStep) {this.scale = 'second'; this.step = 10;}
  303. if (stepSecond*5 > minimumStep) {this.scale = 'second'; this.step = 5;}
  304. if (stepSecond > minimumStep) {this.scale = 'second'; this.step = 1;}
  305. if (stepMillisecond*200 > minimumStep) {this.scale = 'millisecond'; this.step = 200;}
  306. if (stepMillisecond*100 > minimumStep) {this.scale = 'millisecond'; this.step = 100;}
  307. if (stepMillisecond*50 > minimumStep) {this.scale = 'millisecond'; this.step = 50;}
  308. if (stepMillisecond*10 > minimumStep) {this.scale = 'millisecond'; this.step = 10;}
  309. if (stepMillisecond*5 > minimumStep) {this.scale = 'millisecond'; this.step = 5;}
  310. if (stepMillisecond > minimumStep) {this.scale = 'millisecond'; this.step = 1;}
  311. };
  312. /**
  313. * Snap a date to a rounded value.
  314. * The snap intervals are dependent on the current scale and step.
  315. * Static function
  316. * @param {Date} date the date to be snapped.
  317. * @param {string} scale Current scale, can be 'millisecond', 'second',
  318. * 'minute', 'hour', 'weekday, 'day', 'month', 'year'.
  319. * @param {number} step Current step (1, 2, 4, 5, ...
  320. * @return {Date} snappedDate
  321. */
  322. TimeStep.snap = function(date, scale, step) {
  323. var clone = moment(date);
  324. if (scale == 'year') {
  325. var year = clone.year() + Math.round(clone.month() / 12);
  326. clone.year(Math.round(year / step) * step);
  327. clone.month(0);
  328. clone.date(0);
  329. clone.hours(0);
  330. clone.minutes(0);
  331. clone.seconds(0);
  332. clone.milliseconds(0);
  333. }
  334. else if (scale == 'month') {
  335. if (clone.date() > 15) {
  336. clone.date(1);
  337. clone.add(1, 'month');
  338. // important: first set Date to 1, after that change the month.
  339. }
  340. else {
  341. clone.date(1);
  342. }
  343. clone.hours(0);
  344. clone.minutes(0);
  345. clone.seconds(0);
  346. clone.milliseconds(0);
  347. }
  348. else if (scale == 'day') {
  349. //noinspection FallthroughInSwitchStatementJS
  350. switch (step) {
  351. case 5:
  352. case 2:
  353. clone.hours(Math.round(clone.hours() / 24) * 24); break;
  354. default:
  355. clone.hours(Math.round(clone.hours() / 12) * 12); break;
  356. }
  357. clone.minutes(0);
  358. clone.seconds(0);
  359. clone.milliseconds(0);
  360. }
  361. else if (scale == 'weekday') {
  362. //noinspection FallthroughInSwitchStatementJS
  363. switch (step) {
  364. case 5:
  365. case 2:
  366. clone.hours(Math.round(clone.hours() / 12) * 12); break;
  367. default:
  368. clone.hours(Math.round(clone.hours() / 6) * 6); break;
  369. }
  370. clone.minutes(0);
  371. clone.seconds(0);
  372. clone.milliseconds(0);
  373. }
  374. else if (scale == 'hour') {
  375. switch (step) {
  376. case 4:
  377. clone.minutes(Math.round(clone.minutes() / 60) * 60); break;
  378. default:
  379. clone.minutes(Math.round(clone.minutes() / 30) * 30); break;
  380. }
  381. clone.seconds(0);
  382. clone.milliseconds(0);
  383. } else if (scale == 'minute') {
  384. //noinspection FallthroughInSwitchStatementJS
  385. switch (step) {
  386. case 15:
  387. case 10:
  388. clone.minutes(Math.round(clone.minutes() / 5) * 5);
  389. clone.seconds(0);
  390. break;
  391. case 5:
  392. clone.seconds(Math.round(clone.seconds() / 60) * 60); break;
  393. default:
  394. clone.seconds(Math.round(clone.seconds() / 30) * 30); break;
  395. }
  396. clone.milliseconds(0);
  397. }
  398. else if (scale == 'second') {
  399. //noinspection FallthroughInSwitchStatementJS
  400. switch (step) {
  401. case 15:
  402. case 10:
  403. clone.seconds(Math.round(clone.seconds() / 5) * 5);
  404. clone.milliseconds(0);
  405. break;
  406. case 5:
  407. clone.milliseconds(Math.round(clone.milliseconds() / 1000) * 1000); break;
  408. default:
  409. clone.milliseconds(Math.round(clone.milliseconds() / 500) * 500); break;
  410. }
  411. }
  412. else if (scale == 'millisecond') {
  413. var _step = step > 5 ? step / 2 : 1;
  414. clone.milliseconds(Math.round(clone.milliseconds() / _step) * _step);
  415. }
  416. return clone;
  417. };
  418. /**
  419. * Check if the current value is a major value (for example when the step
  420. * is DAY, a major value is each first day of the MONTH)
  421. * @return {boolean} true if current date is major, else false.
  422. */
  423. TimeStep.prototype.isMajor = function() {
  424. if (this.switchedYear == true) {
  425. switch (this.scale) {
  426. case 'year':
  427. case 'month':
  428. case 'weekday':
  429. case 'day':
  430. case 'hour':
  431. case 'minute':
  432. case 'second':
  433. case 'millisecond':
  434. return true;
  435. default:
  436. return false;
  437. }
  438. }
  439. else if (this.switchedMonth == true) {
  440. switch (this.scale) {
  441. case 'weekday':
  442. case 'day':
  443. case 'hour':
  444. case 'minute':
  445. case 'second':
  446. case 'millisecond':
  447. return true;
  448. default:
  449. return false;
  450. }
  451. }
  452. else if (this.switchedDay == true) {
  453. switch (this.scale) {
  454. case 'millisecond':
  455. case 'second':
  456. case 'minute':
  457. case 'hour':
  458. return true;
  459. default:
  460. return false;
  461. }
  462. }
  463. var date = this.moment(this.current);
  464. switch (this.scale) {
  465. case 'millisecond':
  466. return (date.milliseconds() == 0);
  467. case 'second':
  468. return (date.seconds() == 0);
  469. case 'minute':
  470. return (date.hours() == 0) && (date.minutes() == 0);
  471. case 'hour':
  472. return (date.hours() == 0);
  473. case 'weekday': // intentional fall through
  474. case 'day':
  475. return (date.date() == 1);
  476. case 'month':
  477. return (date.month() == 0);
  478. case 'year':
  479. return false;
  480. default:
  481. return false;
  482. }
  483. };
  484. /**
  485. * Returns formatted text for the minor axislabel, depending on the current
  486. * date and the scale. For example when scale is MINUTE, the current time is
  487. * formatted as "hh:mm".
  488. * @param {Date} [date] custom date. if not provided, current date is taken
  489. */
  490. TimeStep.prototype.getLabelMinor = function(date) {
  491. if (date == undefined) {
  492. date = this.current;
  493. }
  494. var format = this.format.minorLabels[this.scale];
  495. return (format && format.length > 0) ? this.moment(date).format(format) : '';
  496. };
  497. /**
  498. * Returns formatted text for the major axis label, depending on the current
  499. * date and the scale. For example when scale is MINUTE, the major scale is
  500. * hours, and the hour will be formatted as "hh".
  501. * @param {Date} [date] custom date. if not provided, current date is taken
  502. */
  503. TimeStep.prototype.getLabelMajor = function(date) {
  504. if (date == undefined) {
  505. date = this.current;
  506. }
  507. var format = this.format.majorLabels[this.scale];
  508. return (format && format.length > 0) ? this.moment(date).format(format) : '';
  509. };
  510. TimeStep.prototype.getClassName = function() {
  511. var _moment = this.moment;
  512. var m = this.moment(this.current);
  513. var current = m.locale ? m.locale('en') : m.lang('en'); // old versions of moment have .lang() function
  514. var step = this.step;
  515. function even(value) {
  516. return (value / step % 2 == 0) ? ' vis-even' : ' vis-odd';
  517. }
  518. function today(date) {
  519. if (date.isSame(new Date(), 'day')) {
  520. return ' vis-today';
  521. }
  522. if (date.isSame(_moment().add(1, 'day'), 'day')) {
  523. return ' vis-tomorrow';
  524. }
  525. if (date.isSame(_moment().add(-1, 'day'), 'day')) {
  526. return ' vis-yesterday';
  527. }
  528. return '';
  529. }
  530. function currentWeek(date) {
  531. return date.isSame(new Date(), 'week') ? ' vis-current-week' : '';
  532. }
  533. function currentMonth(date) {
  534. return date.isSame(new Date(), 'month') ? ' vis-current-month' : '';
  535. }
  536. function currentYear(date) {
  537. return date.isSame(new Date(), 'year') ? ' vis-current-year' : '';
  538. }
  539. switch (this.scale) {
  540. case 'millisecond':
  541. return today(current) +
  542. even(current.milliseconds()).trim();
  543. case 'second':
  544. return today(current) +
  545. even(current.seconds()).trim();
  546. case 'minute':
  547. return today(current) +
  548. even(current.minutes()).trim();
  549. case 'hour':
  550. return 'vis-h' + current.hours() + (this.step == 4 ? '-h' + (current.hours() + 4) : '') +
  551. today(current) +
  552. even(current.hours());
  553. case 'weekday':
  554. return 'vis-' + current.format('dddd').toLowerCase() +
  555. today(current) +
  556. currentWeek(current) +
  557. even(current.date());
  558. case 'day':
  559. return 'vis-day' + current.date() +
  560. ' vis-' + current.format('MMMM').toLowerCase() +
  561. today(current) +
  562. currentMonth(current) +
  563. this.step <= 2 ? today(current) : '' +
  564. this.step <= 2 ? ' vis-' + current.format('dddd').toLowerCase() : '' +
  565. even(current.date() - 1);
  566. case 'month':
  567. return 'vis-' + current.format('MMMM').toLowerCase() +
  568. currentMonth(current) +
  569. even(current.month());
  570. case 'year':
  571. var year = current.year();
  572. return 'vis-year' + year +
  573. currentYear(current) +
  574. even(year);
  575. default:
  576. return '';
  577. }
  578. };
  579. module.exports = TimeStep;