feat: add repeating tasks

backend/main.py

@@ -3,7 +3,7 @@ import json
 import time
 from collections import defaultdict, deque
 from contextlib import asynccontextmanager
-from datetime import datetime
+from datetime import datetime, timedelta
 from pathlib import Path
 from uuid import UUID
 
@@ -26,8 +26,8 @@ from .auth import (
     verify_password,
 )
 from .db import create_schema, get_db
-from .models import AppState, Folder, Session, Task, TaskList, User, utcnow
-from .mvp import audit
+from .models import AppState, Folder, RecurrenceTemplate, Session, Task, TaskList, User, utcnow
+from .mvp import audit, occurrences
 from .mvp import router as mvp_router
 from .schemas import (
     BatchResult,
@@ -624,16 +624,33 @@ async def update_task(
     user: User = Depends(current_user),
     db: AsyncSession = Depends(get_db),
 ):
+    task = await db.scalar(select(Task).where(Task.id == task_id, Task.user_id == user.id, Task.deleted_at.is_(None)))
+    if task is None:
+        raise HTTPException(status_code=404, detail="任务不存在")
     data = payload.model_dump(exclude_unset=True)
     expected_version = data.pop("version")
+    recurrence = None
+    if data.get("completed") is True:
+        recurrence = await db.scalar(select(RecurrenceTemplate).where(
+            RecurrenceTemplate.task_id == task_id, RecurrenceTemplate.user_id == user.id
+        ))
+        if recurrence:
+            next_items = occurrences(
+                recurrence.rrule,
+                recurrence.starts_at,
+                recurrence.starts_at + timedelta(microseconds=1),
+                recurrence.starts_at + timedelta(days=3660),
+                recurrence.ends_at,
+            )
+            if next_items:
+                data["completed"] = False
+                data["due_at"] = next_items[0]
+                recurrence.starts_at = next_items[0]
     if "list_id" in data:
         await _owned_list(db, user.id, data["list_id"])
-        parent_id = await db.scalar(
-            select(Task.parent_id).where(Task.id == task_id, Task.user_id == user.id)
-        )
-        if parent_id:
+        if task.parent_id:
             parent_list = await db.scalar(
-                select(Task.list_id).where(Task.id == parent_id, Task.user_id == user.id)
+                select(Task.list_id).where(Task.id == task.parent_id, Task.user_id == user.id)
             )
             if parent_list != data["list_id"]:
                 raise HTTPException(status_code=400, detail="子任务必须与父任务属于同一清单")

backend/mvp.py

@@ -186,6 +186,17 @@ def ensure_real_occurrence(template: RecurrenceTemplate, occurrence_at: datetime
             raise HTTPException(422, "occurrence_at 晚于该重复规则的有效截止时间")
 
 
+@router.get("/tasks/{task_id}/recurrence")
+async def get_task_recurrence(task_id: UUID, user: User = Depends(current_user), db: AsyncSession = Depends(get_db)):
+    await owned_task(db, user.id, task_id)
+    row = await db.scalar(select(RecurrenceTemplate).where(
+        RecurrenceTemplate.task_id == task_id, RecurrenceTemplate.user_id == user.id
+    ))
+    if row is None:
+        return None
+    return {"id": row.id, "task_id": row.task_id, "rrule": row.rrule, "starts_at": row.starts_at, "ends_at": row.ends_at}
+
+
 @router.post("/recurrences", status_code=201)
 async def create_recurrence(payload: RecurrenceCreate, user: User = Depends(current_user), db: AsyncSession = Depends(get_db)):
     task = await owned_task(db, user.id, payload.task_id)
@@ -779,12 +790,14 @@ async def export_json(user: User = Depends(current_user), db: AsyncSession = Dep
     def serialize(row, fields):
         return {f: (str(v) if isinstance((v := getattr(row, f)), UUID) else v.isoformat() if isinstance(v, (date, datetime)) else v) for f in fields}
     folders = list((await db.scalars(select(Folder).where(Folder.user_id == user.id))).all()); lists = list((await db.scalars(select(TaskList).where(TaskList.user_id == user.id))).all()); tasks = list((await db.scalars(select(Task).where(Task.user_id == user.id))).all()); habits = list((await db.scalars(select(Habit).where(Habit.user_id == user.id))).all()); countdowns = list((await db.scalars(select(Countdown).where(Countdown.user_id == user.id))).all())
+    recurrences = list((await db.scalars(select(RecurrenceTemplate).where(RecurrenceTemplate.user_id == user.id))).all())
     return {
         "version": 1,
         "exported_at": utcnow(),
         "folders": [serialize(x, ["id", "name", "position", "deleted_at"]) for x in folders],
         "lists": [serialize(x, ["id", "folder_id", "name", "is_inbox", "position", "deleted_at"]) for x in lists],
         "tasks": [serialize(x, ["id", "list_id", "parent_id", "title", "description", "priority", "completed", "due_at", "external_id", "deleted_at"]) for x in tasks],
+        "recurrences": [serialize(x, ["id", "task_id", "rrule", "starts_at", "ends_at"]) for x in recurrences],
         "habits": [serialize(x, ["id", "name", "kind", "target", "max_value", "schedule_type", "weekdays", "month_days", "interval_days", "start_date", "archived_at", "position"]) for x in habits],
         "countdowns": [serialize(x, ["id", "title", "event_date", "calendar_mode", "lunar_month", "lunar_day", "ignore_year", "kind", "repeat_rule", "icon", "pinned", "archived_at", "created_at", "updated_at"]) for x in countdowns],
     }
@@ -852,6 +865,17 @@ async def restore_json(payload: dict, mode: str = Query("merge", pattern="^(merg
     for task_id, old_parent_id in pending_tasks:
         if old_parent_id and old_parent_id in task_id_map:
             await db.execute(update(Task).where(Task.id == task_id, Task.user_id == user.id).values(parent_id=task_id_map[old_parent_id]))
+    for raw in payload.get("recurrences", []):
+        task_id = task_id_map.get(raw.get("task_id"))
+        if not task_id:
+            continue
+        db.add(RecurrenceTemplate(
+            user_id=user.id,
+            task_id=task_id,
+            rrule=raw["rrule"],
+            starts_at=datetime.fromisoformat(raw["starts_at"]),
+            ends_at=datetime.fromisoformat(raw["ends_at"]) if raw.get("ends_at") else None,
+        ))
     for raw in payload.get("habits", []):
         row = Habit(
             user_id=user.id,