feat: repeat tasks after completion

frontend/src/lib/task-utils.test.ts

@@ -1,5 +1,5 @@
 import { describe, expect, it } from 'vitest'
-import { buildTaskRrule, classifyTaskForToday, defaultTaskDueAt, filterTasks, groupTaskTree, isSameTaskSortTier, moveItemWithinScope, parseTaskRrule, renderMarkdown, toDateTimeLocal } from './task-utils'
+import { buildTaskRecurrencePayload, buildTaskRrule, classifyTaskForToday, defaultTaskDueAt, filterTasks, groupTaskTree, isSameTaskSortTier, moveItemWithinScope, parseTaskRecurrence, parseTaskRrule, renderMarkdown, toDateTimeLocal } from './task-utils'
 
 type SearchTask = {
   id: string
@@ -73,6 +73,19 @@ describe('task utilities', () => {
     expect(() => buildTaskRrule({ frequency: 'daily', interval: 0, weekdays: [], monthDays: [], endMode: 'never', count: 10, until: '' })).toThrow('重复间隔至少为 1')
   })
 
+  it('builds a distinct completion-trigger payload and parses it without RRULE', () => {
+    expect(buildTaskRecurrencePayload('after_completion', { afterCompletionDays: '7' })).toEqual({ trigger_mode: 'after_completion', after_completion_days: 7 })
+    expect(parseTaskRecurrence({ rrule: null, trigger_mode: 'after_completion', after_completion_days: 14 })).toEqual({ option: 'after_completion', afterCompletionDays: 14 })
+    expect(() => buildTaskRecurrencePayload('after_completion', { afterCompletionDays: '1.5' })).toThrow('请输入 1 到 3650 的整数天数')
+    expect(() => buildTaskRecurrencePayload('after_completion', { afterCompletionDays: '0' })).toThrow('请输入 1 到 3650 的整数天数')
+    expect(() => buildTaskRecurrencePayload('after_completion', { afterCompletionDays: '3651' })).toThrow('请输入 1 到 3650 的整数天数')
+  })
+
+  it('builds scheduled recurrence payloads separately from completion triggers', () => {
+    expect(buildTaskRecurrencePayload('daily', { afterCompletionDays: '1' })).toEqual({ trigger_mode: 'scheduled', rrule: 'FREQ=DAILY' })
+    expect(buildTaskRecurrencePayload('none', { afterCompletionDays: '1' })).toEqual({})
+  })
+
   it('renders safe basic markdown and strips unsafe html', () => {
     const html = renderMarkdown('# Plan\n**bold** [link](https://example.com)\n<script>alert(1)</script>')
     expect(html).toContain('<h1>Plan</h1>')