File size: 36,753 Bytes
bc20498
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
import { addMeltEventListener, makeElement, createElHelpers, effect, executeCallbacks, generateIds, isBrowser, isHTMLElement, isValidIndex, kbd, omit, overridable, styleToString, toWritableStores, } from '../../internal/helpers/index.js';
import { areAllDaysBetweenValid, createFormatter, createMonths, dateStore, getAnnouncer, getDefaultDate, getSelectableCells, isAfter, isBefore, isBetweenInclusive, isCalendarCell, parseStringToDateValue, setPlaceholderToNodeValue, toDate, } from '../../internal/helpers/date/index.js';
import { withGet } from '../../internal/helpers/withGet.js';
import { getLocalTimeZone, isSameDay, isSameMonth, isToday, } from '@internationalized/date';
import { tick } from 'svelte';
import { derived, writable } from 'svelte/store';
const defaults = {
    isDateDisabled: undefined,
    isDateUnavailable: undefined,
    value: undefined,
    defaultValue: {
        start: undefined,
        end: undefined,
    },
    preventDeselect: false,
    numberOfMonths: 1,
    pagedNavigation: false,
    weekStartsOn: 0,
    fixedWeeks: false,
    calendarLabel: 'Event Date',
    locale: 'en',
    minValue: undefined,
    maxValue: undefined,
    disabled: false,
    readonly: false,
    weekdayFormat: 'narrow',
};
const { name } = createElHelpers('calendar');
export const rangeCalendarIdParts = ['calendar', 'accessibleHeading'];
export function createRangeCalendar(props) {
    const withDefaults = { ...defaults, ...props };
    const options = toWritableStores({
        ...omit(withDefaults, 'value', 'placeholder'),
    });
    const { preventDeselect, numberOfMonths, pagedNavigation, weekStartsOn, fixedWeeks, calendarLabel, locale, minValue, maxValue, disabled, readonly, weekdayFormat, } = options;
    const ids = toWritableStores({ ...generateIds(rangeCalendarIdParts), ...withDefaults.ids });
    const defaultDate = getDefaultDate({
        defaultValue: withDefaults.defaultValue?.start,
        defaultPlaceholder: withDefaults.defaultPlaceholder,
    });
    const formatter = createFormatter(locale.get());
    const valueWritable = withDefaults.value ?? writable(withDefaults.defaultValue);
    const value = overridable(valueWritable, withDefaults.onValueChange);
    if (!value.get()) {
        value.set(withDefaults.defaultValue);
    }
    const startValue = withGet(writable(value.get().start ?? withDefaults.defaultValue?.start));
    const endValue = withGet(writable(value.get().end ?? withDefaults.defaultValue?.end));
    const placeholderWritable = withDefaults.placeholder ?? writable(withDefaults.defaultPlaceholder ?? defaultDate);
    const placeholder = dateStore(overridable(placeholderWritable, withDefaults.onPlaceholderChange), withDefaults.defaultPlaceholder ?? defaultDate);
    const focusedValue = withGet(writable(null));
    const lastPressedDateValue = withGet(writable(null));
    const months = withGet(writable(createMonths({
        dateObj: placeholder.get(),
        weekStartsOn: withDefaults.weekStartsOn,
        locale: withDefaults.locale,
        fixedWeeks: withDefaults.fixedWeeks,
        numberOfMonths: withDefaults.numberOfMonths,
    })));
    /**
     * A derived store that maintains the currently visible months in the calendar,
     * which we use to determine how keyboard navigation and if we should apply
     * `data-outside-month` to cells.
     */
    const visibleMonths = withGet(derived([months], ([$months]) => {
        return $months.map((month) => {
            return month.value;
        });
    }));
    const isOutsideVisibleMonths = withGet(derived([visibleMonths], ([$visibleMonths]) => {
        return (date) => {
            return !$visibleMonths.some((month) => isSameMonth(date, month));
        };
    }));
    const isDateDisabled = withGet(derived([options.isDateDisabled, minValue, maxValue], ([$isDateDisabled, $minValue, $maxValue]) => {
        return (date) => {
            if ($isDateDisabled?.(date))
                return true;
            if ($minValue && isBefore(date, $minValue))
                return true;
            if ($maxValue && isAfter(date, $maxValue))
                return true;
            return false;
        };
    }));
    const isDateUnavailable = withGet(derived([options.isDateUnavailable], ([$isDateUnavailable]) => {
        return (date) => {
            if ($isDateUnavailable?.(date))
                return true;
            return false;
        };
    }));
    const isStartInvalid = derived([startValue, isDateUnavailable, isDateDisabled], ([$startValue, $isDateUnavailable, $isDateDisabled]) => {
        if (!$startValue)
            return false;
        return $isDateUnavailable($startValue) || $isDateDisabled($startValue);
    });
    const isEndInvalid = derived([endValue, isDateUnavailable, isDateDisabled], ([$endValue, $isDateUnavailable, $isDateDisabled]) => {
        if (!$endValue)
            return false;
        return $isDateUnavailable($endValue) || $isDateDisabled($endValue);
    });
    const isInvalid = derived([startValue, endValue, isEndInvalid, isStartInvalid], ([$startValue, $endValue, $isEndInvalid, $isStartInvalid]) => {
        if ($isStartInvalid || $isEndInvalid) {
            return true;
        }
        if ($endValue && $startValue && isBefore($endValue, $startValue)) {
            return true;
        }
        return false;
    });
    const isNextButtonDisabled = withGet.derived([months, maxValue, disabled], ([$months, $maxValue, $disabled]) => {
        if (!$maxValue || !$months.length)
            return false;
        if ($disabled)
            return true;
        const lastMonthInView = $months[$months.length - 1].value;
        const firstMonthOfNextPage = lastMonthInView.add({ months: 1 }).set({ day: 1 });
        return isAfter(firstMonthOfNextPage, $maxValue);
    });
    const isPrevButtonDisabled = withGet.derived([months, minValue, disabled], ([$months, $minValue, $disabled]) => {
        if (!$minValue || !$months.length)
            return false;
        if ($disabled)
            return true;
        const firstMonthInView = $months[0].value;
        const lastMonthOfPrevPage = firstMonthInView.subtract({ months: 1 }).set({ day: 35 });
        return isBefore(lastMonthOfPrevPage, $minValue);
    });
    let announcer = getAnnouncer();
    const headingValue = withGet.derived([months, locale], ([$months, $locale]) => {
        if (!$months.length)
            return '';
        if ($locale !== formatter.getLocale()) {
            formatter.setLocale($locale);
        }
        if ($months.length === 1) {
            const month = toDate($months[0].value);
            return `${formatter.fullMonthAndYear(month)}`;
        }
        const startMonth = toDate($months[0].value);
        const endMonth = toDate($months[$months.length - 1].value);
        const startMonthName = formatter.fullMonth(startMonth);
        const endMonthName = formatter.fullMonth(endMonth);
        const startMonthYear = formatter.fullYear(startMonth);
        const endMonthYear = formatter.fullYear(endMonth);
        const content = startMonthYear === endMonthYear
            ? `${startMonthName} - ${endMonthName} ${endMonthYear}`
            : `${startMonthName} ${startMonthYear} - ${endMonthName} ${endMonthYear}`;
        return content;
    });
    const fullCalendarLabel = withGet.derived([headingValue, calendarLabel], ([$headingValue, $calendarLabel]) => {
        return `${$calendarLabel}, ${$headingValue}`;
    });
    const calendar = makeElement(name(), {
        stores: [fullCalendarLabel, isInvalid, ids.calendar, disabled, readonly],
        returned: ([$fullCalendarLabel, $isInvalid, $calendarId, $disabled, $readonly]) => {
            return {
                id: $calendarId,
                role: 'application',
                'aria-label': $fullCalendarLabel,
                'data-invalid': $isInvalid ? '' : undefined,
                'data-disabled': $disabled ? '' : undefined,
                'data-readonly': $readonly ? '' : undefined,
            };
        },
        action: (node) => {
            /**
             * Create the accessible heading for the calendar
             * when the grid is mounted. The label is updated
             * via an effect when the active date or label changes.
             */
            createAccessibleHeading(node, fullCalendarLabel.get());
            announcer = getAnnouncer();
            const unsubKb = addMeltEventListener(node, 'keydown', handleCalendarKeydown);
            return {
                destroy() {
                    unsubKb();
                },
            };
        },
    });
    const heading = makeElement(name('heading'), {
        stores: [disabled],
        returned: ([$disabled]) => {
            return {
                'aria-hidden': true,
                'data-disabled': $disabled ? '' : undefined,
            };
        },
    });
    const grid = makeElement(name('grid'), {
        stores: [readonly, disabled],
        returned: ([$readonly, $disabled]) => ({
            tabindex: -1,
            role: 'grid',
            'aria-readonly': $readonly ? 'true' : undefined,
            'aria-disabled': $disabled ? 'true' : undefined,
            'data-readonly': $readonly ? '' : undefined,
            'data-disabled': $disabled ? '' : undefined,
        }),
    });
    const prevButton = makeElement(name('prevButton'), {
        stores: [isPrevButtonDisabled],
        returned: ([$isPrevButtonDisabled]) => {
            const disabled = $isPrevButtonDisabled;
            return {
                role: 'button',
                type: 'button',
                'aria-label': 'Previous',
                'aria-disabled': disabled ? 'true' : undefined,
                disabled: disabled ? true : undefined,
                'data-disabled': disabled ? '' : undefined,
            };
        },
        action: (node) => {
            const unsub = executeCallbacks(addMeltEventListener(node, 'click', () => {
                prevPage();
            }));
            return {
                destroy: unsub,
            };
        },
    });
    const nextButton = makeElement(name('nextButton'), {
        stores: [isNextButtonDisabled],
        returned: ([$isNextButtonDisabled]) => {
            const disabled = $isNextButtonDisabled;
            return {
                role: 'button',
                type: 'button',
                'aria-label': 'Next',
                'aria-disabled': disabled ? 'true' : undefined,
                disabled: disabled ? true : undefined,
                'data-disabled': disabled ? '' : undefined,
            };
        },
        action: (node) => {
            const unsub = executeCallbacks(addMeltEventListener(node, 'click', () => {
                nextPage();
            }));
            return {
                destroy: unsub,
            };
        },
    });
    const isSelectionStart = derived([startValue], ([$startValue]) => {
        return (date) => {
            if (!$startValue)
                return false;
            return isSameDay($startValue, date);
        };
    });
    const isSelectionEnd = derived([endValue], ([$endValue]) => {
        return (date) => {
            if (!$endValue)
                return false;
            return isSameDay($endValue, date);
        };
    });
    const isSelected = derived([startValue, endValue], ([$startValue, $endValue]) => {
        return (date) => {
            if ($startValue && isSameDay($startValue, date))
                return true;
            if ($endValue && isSameDay($endValue, date))
                return true;
            if ($endValue && $startValue) {
                return isBetweenInclusive(date, $startValue, $endValue);
            }
            return false;
        };
    });
    const highlightedRange = withGet.derived([startValue, endValue, focusedValue, isDateDisabled, isDateUnavailable], ([$startValue, $endValue, $focusedValue, $isDateDisabled, $isDateUnavailable]) => {
        if ($startValue && $endValue)
            return null;
        if (!$startValue || !$focusedValue)
            return null;
        const isStartBeforeFocused = isBefore($startValue, $focusedValue);
        const start = isStartBeforeFocused ? $startValue : $focusedValue;
        const end = isStartBeforeFocused ? $focusedValue : $startValue;
        if (isSameDay(start.add({ days: 1 }), end)) {
            return {
                start: start,
                end: end,
            };
        }
        const isValid = areAllDaysBetweenValid(start, end, $isDateUnavailable, $isDateDisabled);
        if (isValid) {
            return {
                start: start,
                end: end,
            };
        }
        return null;
    });
    /**
     * An individual date cell in the calendar grid, which represents a
     * single day in the month.
     */
    const cell = makeElement(name('cell'), {
        stores: [
            isSelected,
            isSelectionEnd,
            isSelectionStart,
            highlightedRange,
            isDateDisabled,
            isDateUnavailable,
            placeholder,
            isOutsideVisibleMonths,
        ],
        returned: ([$isSelected, $isSelectionEnd, $isSelectionStart, $highlightedRange, $isDateDisabled, $isDateUnavailable, $placeholder, $isOutsideVisibleMonths,]) => {
            return (cellValue, monthValue) => {
                const cellDate = toDate(cellValue);
                const isDisabled = $isDateDisabled(cellValue);
                const isUnavailable = $isDateUnavailable(cellValue);
                const isDateToday = isToday(cellValue, getLocalTimeZone());
                const isOutsideMonth = !isSameMonth(cellValue, monthValue);
                const isFocusedDate = isSameDay(cellValue, $placeholder);
                const isOutsideVisibleMonths = $isOutsideVisibleMonths(cellValue);
                const isSelectedDate = $isSelected(cellValue);
                const isSelectionStart = $isSelectionStart(cellValue);
                const isSelectionEnd = $isSelectionEnd(cellValue);
                const isHighlighted = $highlightedRange
                    ? isBetweenInclusive(cellValue, $highlightedRange.start, $highlightedRange.end)
                    : false;
                const labelText = formatter.custom(cellDate, {
                    weekday: 'long',
                    month: 'long',
                    day: 'numeric',
                    year: 'numeric',
                });
                return {
                    role: 'button',
                    'aria-label': labelText,
                    'aria-selected': isSelectedDate ? true : undefined,
                    'aria-disabled': isOutsideMonth || isDisabled || isUnavailable ? true : undefined,
                    'data-selected': isSelectedDate ? true : undefined,
                    'data-selection-start': isSelectionStart ? true : undefined,
                    'data-selection-end': isSelectionEnd ? true : undefined,
                    'data-value': cellValue.toString(),
                    'data-disabled': isDisabled || isOutsideMonth ? '' : undefined,
                    'data-unavailable': isUnavailable ? '' : undefined,
                    'data-today': isDateToday ? '' : undefined,
                    'data-outside-month': isOutsideMonth ? '' : undefined,
                    'data-outside-visible-months': isOutsideVisibleMonths ? '' : undefined,
                    'data-focused': isFocusedDate ? '' : undefined,
                    'data-highlighted': isHighlighted ? '' : undefined,
                    tabindex: isFocusedDate ? 0 : isOutsideMonth || isDisabled ? undefined : -1,
                };
            };
        },
        action: (node) => {
            const getElArgs = () => {
                const value = node.getAttribute('data-value');
                const label = node.getAttribute('data-label');
                const disabled = node.hasAttribute('data-disabled');
                return {
                    value,
                    label: label ?? node.textContent ?? null,
                    disabled: disabled ? true : false,
                };
            };
            const unsub = executeCallbacks(addMeltEventListener(node, 'click', (e) => {
                const args = getElArgs();
                if (args.disabled)
                    return;
                if (!args.value)
                    return;
                handleCellClick(e, parseStringToDateValue(args.value, placeholder.get()));
            }), addMeltEventListener(node, 'mouseenter', () => {
                const args = getElArgs();
                if (args.disabled)
                    return;
                if (!args.value)
                    return;
                focusedValue.set(parseStringToDateValue(args.value, placeholder.get()));
            }), addMeltEventListener(node, 'focusin', () => {
                const args = getElArgs();
                if (args.disabled)
                    return;
                if (!args.value)
                    return;
                focusedValue.set(parseStringToDateValue(args.value, placeholder.get()));
            }));
            return {
                destroy: unsub,
            };
        },
    });
    effect([locale], ([$locale]) => {
        if (formatter.getLocale() === $locale)
            return;
        formatter.setLocale($locale);
    });
    /**
     * Updates the displayed months based on changes in the placeholder value,
     * which determines the months to show in the calendar.
     */
    effect([placeholder], ([$placeholder]) => {
        if (!isBrowser || !$placeholder)
            return;
        const $visibleMonths = visibleMonths.get();
        /**
         * If the placeholder's month is already in the visible months,
         * we don't need to do anything.
         */
        if ($visibleMonths.some((month) => isSameMonth(month, $placeholder))) {
            return;
        }
        const $weekStartsOn = weekStartsOn.get();
        const $locale = locale.get();
        const $fixedWeeks = fixedWeeks.get();
        const $numberOfMonths = numberOfMonths.get();
        const defaultMonthProps = {
            weekStartsOn: $weekStartsOn,
            locale: $locale,
            fixedWeeks: $fixedWeeks,
            numberOfMonths: $numberOfMonths,
        };
        months.set(createMonths({
            ...defaultMonthProps,
            dateObj: $placeholder,
        }));
    });
    /**
     * Updates the displayed months based on changes in the options values,
     * which determines the months to show in the calendar.
     */
    effect([weekStartsOn, locale, fixedWeeks, numberOfMonths], ([$weekStartsOn, $locale, $fixedWeeks, $numberOfMonths]) => {
        const $placeholder = placeholder.get();
        if (!isBrowser || !$placeholder)
            return;
        const defaultMonthProps = {
            weekStartsOn: $weekStartsOn,
            locale: $locale,
            fixedWeeks: $fixedWeeks,
            numberOfMonths: $numberOfMonths,
        };
        months.set(createMonths({
            ...defaultMonthProps,
            dateObj: $placeholder,
        }));
    });
    /**
     * Update the accessible heading's text content when the
     * `fullCalendarLabel` store changes.
     */
    effect([fullCalendarLabel], ([$fullCalendarLabel]) => {
        if (!isBrowser)
            return;
        const node = document.getElementById(ids.accessibleHeading.get());
        if (!isHTMLElement(node))
            return;
        node.textContent = $fullCalendarLabel;
    });
    effect([startValue], ([$startValue]) => {
        if ($startValue && placeholder.get() !== $startValue) {
            placeholder.set($startValue);
        }
    });
    /**
     * A derived store whose value is an array days of the week
     * for the current locale and calendar view.
     *
     * This remains in sync with the `weekStartsOn` prop, so if it is
     * changed, this store and the calendar will update accordingly.
     *
     * If you prefer to format/render the days of the week yourself,
     * you can do so by accessing the first week of the first month,
     * and mapping over the dates to get/format each day of the week.
     */
    const weekdays = derived([months, weekdayFormat, locale], ([$months, $weekdayFormat, _]) => {
        if (!$months.length)
            return [];
        return $months[0].weeks[0].map((date) => {
            return formatter.dayOfWeek(toDate(date), $weekdayFormat);
        });
    });
    /**
     * Creates an accessible heading for the calendar so when it
     * is focused by a screen reader, the date range being displayed
     * is announced.
     */
    function createAccessibleHeading(node, label) {
        if (!isBrowser)
            return;
        const div = document.createElement('div');
        div.style.cssText = styleToString({
            border: '0px',
            clip: 'rect(0px, 0px, 0px, 0px)',
            'clip-path': 'inset(50%)',
            height: '1px',
            margin: '-1px',
            overflow: 'hidden',
            padding: '0px',
            position: 'absolute',
            'white-space': 'nowrap',
            width: '1px',
        });
        const h2 = document.createElement('div');
        h2.textContent = label;
        h2.id = ids.accessibleHeading.get();
        h2.role = 'heading';
        h2.ariaLevel = '2';
        node.insertBefore(div, node.firstChild);
        div.appendChild(h2);
    }
    /**
     * Navigate to the next page of the calendar.
     *
     * @remarks
     * If using paged navigation, this will move the calendar forward
     * by the number of months specified in the `numberOfMonths` prop.
     * If not using paged navigation, this will move the calendar forward
     * by one month.
     *
     * @example
     * ```svelte
     * <script>
     * 	import { createCalendar } from '@melt-ui/svelte';
     *  import { prev } from '../../internal/helpers/array'
     * 	const { { ... }, helpers: { nextPage } } = createCalendar()
     * </script>
     *
     * <button on:click={nextPage} aria-label="Next page">▶️</button>
     * ```
     */
    function nextPage() {
        const $months = months.get();
        const $numberOfMonths = numberOfMonths.get();
        if (pagedNavigation.get()) {
            const firstMonth = $months[0].value;
            placeholder.set(firstMonth.add({ months: $numberOfMonths }));
        }
        else {
            const firstMonth = $months[0].value;
            const newMonths = createMonths({
                dateObj: firstMonth.add({ months: 1 }),
                weekStartsOn: weekStartsOn.get(),
                locale: locale.get(),
                fixedWeeks: fixedWeeks.get(),
                numberOfMonths: $numberOfMonths,
            });
            months.set(newMonths);
            placeholder.set(newMonths[0].value.set({ day: 1 }));
        }
    }
    /**
     * Navigate to the previous page of the calendar.
     *
     * @remarks
     * A helper function to navigate to the previous page of the calendar.
     * If using paged navigation, this will move the calendar backwards
     * by the number of months specified in the `numberOfMonths` prop.
     * If not using paged navigation, this will move the calendar backwards
     * by one month.
     *
     * @example
     * ```svelte
     * <script>
     * 	import { createCalendar } from '@melt-ui/svelte';
     * 	const { { ... }, helpers: { prevPage } } = createCalendar()
     * </script>
     *
     * <button on:click={prevPage} aria-label="Previous page">◀️</button>
     * ```
     */
    function prevPage() {
        const $months = months.get();
        const $numberOfMonths = numberOfMonths.get();
        if (pagedNavigation.get()) {
            const firstMonth = $months[0].value;
            placeholder.set(firstMonth.subtract({ months: $numberOfMonths }));
        }
        else {
            const firstMonth = $months[0].value;
            const newMonths = createMonths({
                dateObj: firstMonth.subtract({ months: 1 }),
                weekStartsOn: weekStartsOn.get(),
                locale: locale.get(),
                fixedWeeks: fixedWeeks.get(),
                numberOfMonths: $numberOfMonths,
            });
            months.set(newMonths);
            placeholder.set(newMonths[0].value.set({ day: 1 }));
        }
    }
    /**
     * Navigate to the previous year of the calendar.
     */
    function nextYear() {
        placeholder.add({ years: 1 });
    }
    /**
     * Navigate to the next year of the calendar.
     */
    function prevYear() {
        placeholder.subtract({ years: 1 });
    }
    const ARROW_KEYS = [kbd.ARROW_DOWN, kbd.ARROW_UP, kbd.ARROW_LEFT, kbd.ARROW_RIGHT];
    /**
     * A helper function to set the year of the active date. This is
     * useful when the user wants to have a select input to change the
     * year of the calendar.
     */
    function setYear(year) {
        placeholder.setDate({ year: year });
    }
    /**
     * A helper function to set the month of the active date. This is
     * useful when the user wants to have a select input to change the
     * month of the calendar.
     */
    function setMonth(month) {
        if (month < 0 || month > 11)
            throw new Error('Month must be between 0 and 11');
        placeholder.setDate({ month: month });
    }
    function handleCellClick(e, date) {
        const $isDateDisabled = isDateDisabled.get();
        const $isDateUnavailable = isDateUnavailable.get();
        if ($isDateDisabled(date) || $isDateUnavailable(date))
            return;
        const $lastPressedDate = lastPressedDateValue.get();
        lastPressedDateValue.set(date);
        const $startValue = startValue.get();
        const $endValue = endValue.get();
        const $highlightedRange = highlightedRange.get();
        if ($startValue && $highlightedRange === null) {
            if (isSameDay($startValue, date) && !preventDeselect.get() && !$endValue) {
                startValue.set(undefined);
                placeholder.set(date);
                announcer.announce('Selected date is now empty.', 'polite');
                return;
            }
            else if (!$endValue) {
                e.preventDefault();
                if ($lastPressedDate && isSameDay($lastPressedDate, date)) {
                    startValue.set(date);
                    announcer.announce(`Selected Date: ${formatter.selectedDate(date, false)}`, 'polite');
                }
                return;
            }
        }
        if ($startValue && $endValue && isSameDay($endValue, date) && !preventDeselect.get()) {
            startValue.set(undefined);
            endValue.set(undefined);
            placeholder.set(date);
            announcer.announce('Selected date is now empty.', 'polite');
            return;
        }
        if (!$startValue) {
            startValue.update(() => {
                announcer.announce(`Selected Date: ${formatter.selectedDate(date, false)}`, 'polite');
                return date;
            });
        }
        else if (!$endValue) {
            endValue.update(() => {
                announcer.announce(`Selected Dates: ${formatter.selectedDate($startValue, false)} to ${formatter.selectedDate(date, false)}`, 'polite');
                return date;
            });
        }
        else if ($endValue && $startValue) {
            endValue.set(undefined);
            startValue.update(() => {
                announcer.announce(`Selected Date: ${formatter.selectedDate(date, false)}`, 'polite');
                return date;
            });
        }
    }
    const SELECT_KEYS = [kbd.ENTER, kbd.SPACE];
    function handleCalendarKeydown(e) {
        const currentCell = e.target;
        if (!isCalendarCell(currentCell))
            return;
        if (!ARROW_KEYS.includes(e.key) && !SELECT_KEYS.includes(e.key))
            return;
        e.preventDefault();
        // the cell that is currently focused
        if (e.key === kbd.ARROW_DOWN) {
            shiftFocus(currentCell, 7);
        }
        if (e.key === kbd.ARROW_UP) {
            shiftFocus(currentCell, -7);
        }
        if (e.key === kbd.ARROW_LEFT) {
            shiftFocus(currentCell, -1);
        }
        if (e.key === kbd.ARROW_RIGHT) {
            shiftFocus(currentCell, 1);
        }
        if (e.key === kbd.SPACE || e.key === kbd.ENTER) {
            const cellValue = currentCell.getAttribute('data-value');
            if (!cellValue)
                return;
            handleCellClick(e, parseStringToDateValue(cellValue, placeholder.get()));
        }
    }
    function shiftFocus(node, add) {
        const $calendarId = ids.calendar.get();
        const candidateCells = getSelectableCells($calendarId);
        if (!candidateCells.length) {
            return;
        }
        const index = candidateCells.indexOf(node);
        const nextIndex = index + add;
        /**
         * If the next cell is within the bounds of the
         * displayed/rendered cells, easy day, just focus it.
         */
        if (isValidIndex(nextIndex, candidateCells)) {
            const nextCell = candidateCells[nextIndex];
            setPlaceholderToNodeValue(nextCell, placeholder);
            return nextCell.focus();
        }
        /**
         * If the next cell is outside the bounds of the
         * displayed/rendered cells, we need to updated the focused
         * value to the prev/next month depending on the direction,
         * and then focus the appropriate cell.
         */
        if (nextIndex < 0) {
            /**
             * Since we're in the negative index range, we need to
             * go back a month, refetch the candidate cells within that
             * month, and then starting at the end of that array, shift
             * focus by the difference between the nextIndex
             */
            // shift the calendar back a month unless previous month is disabled
            if (isPrevButtonDisabled.get())
                return;
            const $months = months.get();
            const firstMonth = $months[0].value;
            const $numberOfMonths = numberOfMonths.get();
            placeholder.set(firstMonth.subtract({ months: $numberOfMonths }));
            // Without a tick here, it seems to be too fast for
            // the DOM to update, with the tick it works great
            tick().then(() => {
                const newCandidateCells = getSelectableCells($calendarId);
                if (!newCandidateCells.length) {
                    return;
                }
                // starting at the end of the array, shift focus by the nextIndex amount
                // since in this case, nextIndex is negative, we'll convert it to a positive
                // before subtracting it from the length of the array
                const newIndex = newCandidateCells.length - Math.abs(nextIndex);
                if (isValidIndex(newIndex, newCandidateCells)) {
                    const newCell = newCandidateCells[newIndex];
                    setPlaceholderToNodeValue(newCell, placeholder);
                    return newCell.focus();
                }
            });
        }
        if (nextIndex >= candidateCells.length) {
            /**
             * Since we're in the positive index range, we need to
             * go forward a month, refetch the candidate cells within that
             * month, and then starting at the beginning of that array,
             * shift focus by the nextIndex amount.
             */
            // shift the calendar forward a month unless next month is disabled
            if (isNextButtonDisabled.get())
                return;
            const $months = months.get();
            const firstMonth = $months[0].value;
            const $numberOfMonths = numberOfMonths.get();
            placeholder.set(firstMonth.add({ months: $numberOfMonths }));
            tick().then(() => {
                const newCandidateCells = getSelectableCells($calendarId);
                if (!newCandidateCells.length) {
                    return;
                }
                /**
                 * We need to determine how far into the next month we need to go
                 * to get the next index. So if we only went over the previous month
                 * by 1, we need to go into the next month by 1 to get the right index.
                 */
                const newIndex = nextIndex - candidateCells.length;
                if (isValidIndex(newIndex, newCandidateCells)) {
                    const nextCell = newCandidateCells[newIndex];
                    return nextCell.focus();
                }
            });
        }
    }
    /**
     * A helper function to determine if a date is disabled,
     * which uses the `Matcher`(s) provided via the `disabled`
     * prop, as well as other internal logic, such as if the
     * date is outside of the current month.
     *
     * Although we set attributes on the cells themselves, this
     * function is useful when you want to conditionally handle
     * something outside of the cell, such as its wrapping element.
     *
     * @example
     * ```svelte
     * {#each dates as date}
     * 	<td role="gridcell" aria-disabled={$isDisabled(date)}>
     * 		<!-- ... -->
     * 	</td>
     * {/each}
     * ```
     *
     * @param date - The `DateValue` to check
     * @returns `true` if the date is disabled, `false` otherwise
     */
    const _isDateDisabled = derived([isDateDisabled, placeholder, minValue, maxValue], ([$isDateDisabled, $placeholder, $minValue, $maxValue]) => {
        return (date) => {
            if ($isDateDisabled(date))
                return true;
            if ($minValue && isBefore(date, $minValue))
                return true;
            if ($maxValue && isAfter(date, $maxValue))
                return true;
            if (!isSameMonth(date, $placeholder))
                return true;
            return false;
        };
    });
    /**
     * Synchronize the `value` store with the individual `startValue`
     * and `endValue` stores that are used by the individual date fields.
     *
     * We only want to update the `value` store when both the `startValue`
     * and `endValue` stores are not `undefined`. This is because the
     * `value` store is used to determine if the date field is completed,
     * and we don't want to mark the date field as completed until both
     * the start and end dates have been selected.
     */
    effect([value], ([$value]) => {
        const $startValue = startValue.get();
        const $endValue = endValue.get();
        if ($value?.start && $value?.end) {
            if ($value.start !== $startValue) {
                startValue.set($value.start);
            }
            if ($value.end !== $endValue) {
                endValue.set($value.end);
            }
            return;
        }
    });
    effect([startValue, endValue], ([$startValue, $endValue]) => {
        const $value = value.get();
        if ($value && $value?.start === $startValue && $value?.end === $endValue)
            return;
        if ($startValue && $endValue) {
            value.update((prev) => {
                if (prev?.start === $startValue && prev?.end === $endValue) {
                    return prev;
                }
                if (isBefore($endValue, $startValue)) {
                    return {
                        start: $endValue,
                        end: $startValue,
                    };
                }
                else {
                    return {
                        start: $startValue,
                        end: $endValue,
                    };
                }
            });
        }
        else if ($value && $value.start && $value.end) {
            value.set({
                start: undefined,
                end: undefined,
            });
        }
    });
    return {
        elements: {
            calendar,
            heading,
            grid,
            cell,
            nextButton,
            prevButton,
        },
        states: {
            placeholder: placeholder.toWritable(),
            months,
            weekdays,
            headingValue,
            value,
            startValue,
            endValue,
        },
        helpers: {
            nextPage,
            prevPage,
            nextYear,
            prevYear,
            setYear,
            setMonth,
            isDateDisabled: _isDateDisabled,
            isDateUnavailable,
        },
        options,
        ids,
    };
}