fix(date-picker): open calendar on min enabled month when current mon…

…th is after max date (#472)

src/lib/calendar/calendar-foundation.ts

@@ -1601,9 +1601,14 @@ export class CalendarFoundation implements ICalendarFoundation {
   private _applyMin(): void {
     this._adapter.toggleHostAttribute(CALENDAR_CONSTANTS.attributes.MIN, !!this._minAttribute, this._minAttribute as string);
 
-    if (this._min && (this._min.getMonth() > this._month || this._min.getFullYear() > this._year)) {
-      this._year = this._min.getFullYear();
-      this._month = this._min.getMonth();
+    if (this._min) {
+      const minFirstOfMonth = new Date(this._min.getFullYear(), this._min.getMonth(), 1);
+      const currentFirstOfMonth = new Date(this._year, this._month, 1);
+
+      if (minFirstOfMonth > currentFirstOfMonth) {
+        this._year = this._min.getFullYear();
+        this._month = this._min.getMonth();
+      }
     }
 
     if (this._isInitialized) {
@@ -1621,9 +1626,14 @@ export class CalendarFoundation implements ICalendarFoundation {
   private _applyMax(): void {
     this._adapter.toggleHostAttribute(CALENDAR_CONSTANTS.attributes.MAX, !!this._maxAttribute, this._maxAttribute as string);
 
-    if (this._max && (this._max.getMonth() < this._month || this._max.getFullYear() < this._year)) {
-      this._year = this._max.getFullYear();
-      this._month = this._max.getMonth();
+    if (this._max) {
+      const maxFirstOfMonth = new Date(this._max.getFullYear(), this._max.getMonth(), 1);
+      const currentFirstOfMonth = new Date(this._year, this._month, 1);
+
+      if (maxFirstOfMonth < currentFirstOfMonth) {
+        this._year = this._max.getFullYear();
+        this._month = this._max.getMonth();
+      }
     }
 
     if (this._isInitialized) {

src/lib/date-picker/base/base-date-picker-adapter.ts

@@ -117,10 +117,7 @@ export abstract class BaseDatePickerAdapter<T extends BaseComponent> extends Bas
   }
 
   public attachCalendar(calendarConfig: Partial<ICalendarComponent>, dropdownConfig?: ICalendarDropdownPopupConfig): void {
-    if (this._calendarDropdown) {
-      this._calendarDropdown?.destroy();
-    }
-
+    this._calendarDropdown?.destroy();
     this._initializeCalendarDropdown();
 
     if (!this._calendarDropdown) {

src/lib/date-picker/base/base-date-picker-foundation.ts

@@ -214,6 +214,13 @@ export abstract class BaseDatePickerFoundation<TAdapter extends IBaseDatePickerA
       activeChangeCallback: this._activeChangeListener
     };
 
+    // If the max date is in the past, set the calendar to the min date
+    const currentDate = new Date().getTime();
+    if (this._min && this._max && this._max.getTime() < currentDate) {
+      calendarConfig.year = this._min.getFullYear();
+      calendarConfig.month = this._min.getMonth();
+    }
+
     this._adapter.attachCalendar(calendarConfig, dropdownConfig);
     this._adapter.addDateSelectListener(this._dateSelectListener);
     this._open = true;

src/test/spec/date-picker/date-picker.spec.ts

@@ -103,6 +103,21 @@ describe('DatePickerComponent', function(this: ITestContext) {
       expect(calendar.month).toEqual(expectedMonth);
     });
 
+    it('should open calendar in month of min date if max is before current month and min is set', function(this: ITestContext) {
+      this.context = setupTestContext(false);
+      const date = new Date();
+      const minDate = new Date(date.getFullYear() - 1, date.getMonth() - 1, 1);
+      this.context.component.min = minDate;
+      this.context.component.max = new Date(date.getFullYear(), date.getMonth() - 1, 1);
+      this.context.append();
+
+      openPopup(this.context.component);
+      const calendar = getCalendar(this.context.component);
+      const expectedMonth = minDate.getMonth();
+
+      expect(calendar.month).toEqual(expectedMonth);
+    });
+
     it('should automatically render a toggle button with a Forge text-field component', function(this: ITestContext) {
       this.context = setupTestContext(false, true, false);