feat: Refactor ScheduleModal to support interval scheduling with date input and deadline toggle

- Updated ChoreSchedule model to include anchor_date and interval_has_deadline.
- Refactored interval scheduling logic in scheduleUtils to use anchor_date.
- Introduced DateInputField component for selecting anchor dates in ScheduleModal.
- Enhanced ScheduleModal to include a stepper for interval days and a toggle for deadline.
- Updated tests for ScheduleModal and scheduleUtils to reflect new interval scheduling logic.
- Added DateInputField tests to ensure proper functionality and prop handling.

frontend/vue-app/src/__tests__/scheduleUtils.spec.ts

@@ -31,26 +31,35 @@ describe('toLocalISODate', () => {
 // ---------------------------------------------------------------------------
 describe('intervalHitsToday', () => {
   it('anchor day hits on itself', () => {
-    // Wednesday = weekday 3
     const wednesday = new Date(2025, 0, 8) // Jan 8, 2025 is a Wednesday
-    expect(intervalHitsToday(3, 2, wednesday)).toBe(true)
+    expect(intervalHitsToday('2025-01-08', 2, wednesday)).toBe(true)
   })
 
-  it('anchor=Wednesday, interval=2, Thursday does NOT hit', () => {
-    const thursday = new Date(2025, 0, 9)
-    expect(intervalHitsToday(3, 2, thursday)).toBe(false)
+  it('anchor=Wednesday(2025-01-08), interval=2, Thursday does NOT hit', () => {
+    const thursday = new Date(2025, 0, 9) // 1 day after anchor, 1 % 2 !== 0
+    expect(intervalHitsToday('2025-01-08', 2, thursday)).toBe(false)
   })
 
-  it('anchor=Wednesday, interval=2, Friday hits (2 days after anchor)', () => {
-    const friday = new Date(2025, 0, 10)
-    expect(intervalHitsToday(3, 2, friday)).toBe(true)
+  it('anchor=Wednesday(2025-01-08), interval=2, Friday hits (2 days after anchor)', () => {
+    const friday = new Date(2025, 0, 10) // 2 days after anchor, 2 % 2 === 0
+    expect(intervalHitsToday('2025-01-08', 2, friday)).toBe(true)
   })
 
   it('interval=1 hits every day', () => {
-    // interval of 1 means every day; diffDays % 1 === 0 always
-    // Note: interval_days=1 is disallowed in UI (min 2) but logic should still work
-    const monday = new Date(2025, 0, 6)
-    expect(intervalHitsToday(1, 1, monday)).toBe(true)
+    const monday = new Date(2025, 0, 6) // anchor is that same Monday
+    expect(intervalHitsToday('2025-01-06', 1, monday)).toBe(true)
+    const tuesday = new Date(2025, 0, 7)
+    expect(intervalHitsToday('2025-01-06', 1, tuesday)).toBe(true)
+  })
+
+  it('returns false for a date before the anchor', () => {
+    const beforeAnchor = new Date(2025, 0, 7) // Jan 7 is before Jan 8 anchor
+    expect(intervalHitsToday('2025-01-08', 2, beforeAnchor)).toBe(false)
+  })
+
+  it('empty anchor string treats localDate as the anchor (always hits)', () => {
+    const today = new Date(2025, 0, 8)
+    expect(intervalHitsToday('', 2, today)).toBe(true)
   })
 })
 
@@ -67,7 +76,8 @@ describe('isScheduledToday', () => {
       { day: 3, hour: 9, minute: 30 }, // Wednesday
     ],
     interval_days: 2,
-    anchor_weekday: 0,
+    anchor_date: '',
+    interval_has_deadline: true,
     interval_hour: 0,
     interval_minute: 0,
   }
@@ -89,7 +99,8 @@ describe('isScheduledToday', () => {
       mode: 'interval',
       day_configs: [],
       interval_days: 2,
-      anchor_weekday: 3, // Wednesday
+      anchor_date: '2025-01-08', // Wednesday
+      interval_has_deadline: true,
       interval_hour: 8,
       interval_minute: 0,
     }
@@ -110,7 +121,8 @@ describe('getDueTimeToday', () => {
     mode: 'days',
     day_configs: [{ day: 1, hour: 8, minute: 30 }],
     interval_days: 2,
-    anchor_weekday: 0,
+    anchor_date: '',
+    interval_has_deadline: true,
     interval_hour: 0,
     interval_minute: 0,
   }
@@ -132,7 +144,8 @@ describe('getDueTimeToday', () => {
       mode: 'interval',
       day_configs: [],
       interval_days: 2,
-      anchor_weekday: 3,
+      anchor_date: '2025-01-08',
+      interval_has_deadline: true,
       interval_hour: 14,
       interval_minute: 45,
     }
@@ -147,13 +160,31 @@ describe('getDueTimeToday', () => {
       mode: 'interval',
       day_configs: [],
       interval_days: 2,
-      anchor_weekday: 3,
+      anchor_date: '2025-01-08',
+      interval_has_deadline: true,
       interval_hour: 14,
       interval_minute: 45,
     }
     const thursday = new Date(2025, 0, 9)
     expect(getDueTimeToday(intervalSchedule, thursday)).toBeNull()
   })
+
+  it('interval mode with interval_has_deadline=false returns null (Anytime)', () => {
+    const intervalSchedule: ChoreSchedule = {
+      child_id: 'c1',
+      task_id: 't1',
+      mode: 'interval',
+      day_configs: [],
+      interval_days: 2,
+      anchor_date: '2025-01-08',
+      interval_has_deadline: false,
+      interval_hour: 14,
+      interval_minute: 45,
+    }
+    const wednesday = new Date(2025, 0, 8)
+    // Even on a hit day, Anytime means no deadline → null
+    expect(getDueTimeToday(intervalSchedule, wednesday)).toBeNull()
+  })
 })
 
 // ---------------------------------------------------------------------------