feat: add task and habit reordering

backend/main.py

@@ -45,6 +45,7 @@ from .schemas import (
     TaskDetailOut,
     TaskOut,
     TaskPage,
+    TaskReorder,
     TaskUpdate,
     UserOut,
 )
@@ -434,16 +435,16 @@ async def restore_list(
 
 
 
-def _encode_cursor(created_at: datetime, task_id: UUID) -> str:
-    raw = json.dumps([created_at.isoformat(), str(task_id)]).encode()
+def _encode_cursor(position: int, created_at: datetime, task_id: UUID) -> str:
+    raw = json.dumps([position, created_at.isoformat(), str(task_id)]).encode()
     return base64.urlsafe_b64encode(raw).decode().rstrip("=")
 
 
-def _decode_cursor(cursor: str) -> tuple[datetime, UUID]:
+def _decode_cursor(cursor: str) -> tuple[int, datetime, UUID]:
     try:
         raw = base64.urlsafe_b64decode(cursor + "=" * (-len(cursor) % 4))
-        timestamp, task_id = json.loads(raw)
-        return datetime.fromisoformat(timestamp), UUID(task_id)
+        position, timestamp, task_id = json.loads(raw)
+        return int(position), datetime.fromisoformat(timestamp), UUID(task_id)
     except (ValueError, TypeError, json.JSONDecodeError) as exc:
         raise HTTPException(status_code=422, detail="无效的游标") from exc
 
@@ -468,7 +469,14 @@ async def create_task(
         if parent is None:
             raise HTTPException(status_code=400, detail="父任务必须是同一清单的顶层任务")
     data = payload.model_dump()
-    task = Task(user_id=user.id, **data)
+    parent_filter = Task.parent_id == payload.parent_id if payload.parent_id else Task.parent_id.is_(None)
+    max_position = await db.scalar(select(func.max(Task.position)).where(
+        Task.user_id == user.id,
+        Task.list_id == payload.list_id,
+        parent_filter,
+        Task.deleted_at.is_(None),
+    ))
+    task = Task(user_id=user.id, position=(max_position if max_position is not None else -1) + 1, **data)
     db.add(task)
     await db.flush()
     audit(db, user.id, "create", "task", task.id)
@@ -516,20 +524,24 @@ async def list_tasks(
             or_(Task.title.ilike(pattern), Task.description.ilike(pattern), list_match)
         )
     total = await db.scalar(select(func.count()).select_from(query.order_by(None).subquery())) or 0
-    ordering = (Task.created_at, Task.id)
+    ordering = (Task.position, Task.created_at, Task.id)
     if page is not None:
         size = page_size or limit
         items = list((await db.scalars(query.order_by(*ordering).offset((page - 1) * size).limit(size))).all())
         return TaskPage(items=await _task_details(db, items), total=total, page=page, page_size=size)
     if cursor:
-        created_at, task_id = _decode_cursor(cursor)
+        position, created_at, task_id = _decode_cursor(cursor)
         query = query.where(
-            or_(Task.created_at > created_at, (Task.created_at == created_at) & (Task.id > task_id))
+            or_(
+                Task.position > position,
+                (Task.position == position) & (Task.created_at > created_at),
+                (Task.position == position) & (Task.created_at == created_at) & (Task.id > task_id),
+            )
         )
     rows = list((await db.scalars(query.order_by(*ordering).limit(limit + 1))).all())
     has_more = len(rows) > limit
     items = rows[:limit]
-    next_cursor = _encode_cursor(items[-1].created_at, items[-1].id) if has_more else None
+    next_cursor = _encode_cursor(items[-1].position, items[-1].created_at, items[-1].id) if has_more else None
     return TaskPage(items=await _task_details(db, items), next_cursor=next_cursor, total=total, page=1, page_size=limit)
 
 
@@ -561,6 +573,36 @@ async def _task_detail(db: AsyncSession, task: Task) -> TaskDetailOut:
     return (await _task_details(db, [task]))[0]
 
 
+@app.put("/api/v1/tasks/reorder", status_code=204)
+async def reorder_tasks(
+    payload: TaskReorder,
+    user: User = Depends(current_user),
+    db: AsyncSession = Depends(get_db),
+):
+    rows = list((await db.scalars(select(Task).where(
+        Task.id.in_(payload.task_ids), Task.user_id == user.id, Task.deleted_at.is_(None)
+    ))).all())
+    if len(rows) != len(payload.task_ids):
+        raise HTTPException(status_code=404, detail="任务不存在")
+    parent_scopes = {row.parent_id for row in rows}
+    if len(parent_scopes) != 1:
+        raise HTTPException(status_code=400, detail="只能调整同一层级任务的顺序")
+    parent_id = next(iter(parent_scopes))
+    scope_query = select(Task).where(
+        Task.user_id == user.id,
+        Task.deleted_at.is_(None),
+        Task.parent_id.is_(None) if parent_id is None else Task.parent_id == parent_id,
+    ).order_by(Task.position, Task.created_at, Task.id)
+    scope_rows = list((await db.scalars(scope_query)).all())
+    requested = set(payload.task_ids)
+    ordered_rows = iter([next(row for row in rows if row.id == task_id) for task_id in payload.task_ids])
+    merged = [next(ordered_rows) if row.id in requested else row for row in scope_rows]
+    for position, row in enumerate(merged):
+        row.position = position
+    await db.commit()
+    return Response(status_code=204)
+
+
 @app.get("/api/v1/tasks/{task_id}", response_model=TaskDetailOut)
 async def get_task(
     task_id: UUID,

backend/models.py

@@ -162,6 +162,7 @@ class Habit(Base):
     interval_days: Mapped[int | None] = mapped_column(Integer, nullable=True)
     start_date: Mapped[date] = mapped_column(Date)
     archived_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True)
+    position: Mapped[int] = mapped_column(Integer, default=0)
     created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=utcnow)
 
 

backend/mvp.py

@@ -525,6 +525,16 @@ class HabitCreate(BaseModel):
         return self
 
 
+class HabitReorder(BaseModel):
+    habit_ids: list[UUID] = Field(min_length=1)
+
+    @model_validator(mode="after")
+    def unique_ids(self):
+        if len(self.habit_ids) != len(set(self.habit_ids)):
+            raise ValueError("habit_ids must be unique")
+        return self
+
+
 class HabitLogInput(BaseModel):
     day: date
     value: float = Field(gt=0)
@@ -541,7 +551,7 @@ class PauseInput(BaseModel):
 
 
 def habit_dict(h):
-    return {"id": h.id, "name": h.name, "kind": h.kind, "target": h.target, "max_value": h.max_value, "schedule_type": h.schedule_type, "weekdays": [int(x) for x in h.weekdays.split(",")] if h.weekdays else None, "month_days": [int(x) for x in h.month_days.split(",")] if h.month_days else None, "interval_days": h.interval_days, "start_date": h.start_date, "archived_at": h.archived_at}
+    return {"id": h.id, "name": h.name, "kind": h.kind, "target": h.target, "max_value": h.max_value, "schedule_type": h.schedule_type, "weekdays": [int(x) for x in h.weekdays.split(",")] if h.weekdays else None, "month_days": [int(x) for x in h.month_days.split(",")] if h.month_days else None, "interval_days": h.interval_days, "start_date": h.start_date, "archived_at": h.archived_at, "position": h.position}
 
 
 async def owned_habit(db, user_id, habit_id):
@@ -552,14 +562,34 @@ async def owned_habit(db, user_id, habit_id):
 
 @router.post("/habits", status_code=201)
 async def create_habit(payload: HabitCreate, user: User = Depends(current_user), db: AsyncSession = Depends(get_db)):
-    row = Habit(user_id=user.id, **payload.model_dump(exclude={"weekdays", "month_days"}), weekdays=",".join(map(str, payload.weekdays)) if payload.weekdays else None, month_days=",".join(map(str, payload.month_days)) if payload.month_days else None)
+    max_position = await db.scalar(select(func.max(Habit.position)).where(Habit.user_id == user.id))
+    row = Habit(user_id=user.id, position=(max_position if max_position is not None else -1) + 1, **payload.model_dump(exclude={"weekdays", "month_days"}), weekdays=",".join(map(str, payload.weekdays)) if payload.weekdays else None, month_days=",".join(map(str, payload.month_days)) if payload.month_days else None)
     db.add(row); await db.commit(); await db.refresh(row); return habit_dict(row)
 
 
 @router.get("/habits")
 async def list_habits(archived: bool = False, user: User = Depends(current_user), db: AsyncSession = Depends(get_db)):
     condition = Habit.archived_at.is_not(None) if archived else Habit.archived_at.is_(None)
-    return [habit_dict(h) for h in (await db.scalars(select(Habit).where(Habit.user_id == user.id, condition).order_by(Habit.created_at))).all()]
+    return [habit_dict(h) for h in (await db.scalars(select(Habit).where(Habit.user_id == user.id, condition).order_by(Habit.position, Habit.created_at))).all()]
+
+
+@router.put("/habits/reorder", status_code=204)
+async def reorder_habits(payload: HabitReorder, user: User = Depends(current_user), db: AsyncSession = Depends(get_db)):
+    rows = list((await db.scalars(select(Habit).where(
+        Habit.id.in_(payload.habit_ids), Habit.user_id == user.id, Habit.archived_at.is_(None)
+    ))).all())
+    if len(rows) != len(payload.habit_ids):
+        raise HTTPException(404, "习惯不存在")
+    scope_rows = list((await db.scalars(select(Habit).where(
+        Habit.user_id == user.id, Habit.archived_at.is_(None)
+    ).order_by(Habit.position, Habit.created_at))).all())
+    requested = set(payload.habit_ids)
+    ordered_rows = iter([next(row for row in rows if row.id == habit_id) for habit_id in payload.habit_ids])
+    merged = [next(ordered_rows) if row.id in requested else row for row in scope_rows]
+    for position, row in enumerate(merged):
+        row.position = position
+    await db.commit()
+    return Response(status_code=204)
 
 
 @router.patch("/habits/{habit_id}")
@@ -623,7 +653,7 @@ def scheduled(h, day):
 @router.get("/habits/grid")
 async def habits_grid(week: date, user: User = Depends(current_user), db: AsyncSession = Depends(get_db)):
     start = week - timedelta(days=week.weekday()); days = [start + timedelta(days=i) for i in range(7)]
-    habits = list((await db.scalars(select(Habit).where(Habit.user_id == user.id, Habit.archived_at.is_(None)).order_by(Habit.created_at))).all())
+    habits = list((await db.scalars(select(Habit).where(Habit.user_id == user.id, Habit.archived_at.is_(None)).order_by(Habit.position, Habit.created_at))).all())
     if not habits:
         return {"days": days, "habits": []}
     habit_ids = [habit.id for habit in habits]
@@ -755,7 +785,7 @@ async def export_json(user: User = Depends(current_user), db: AsyncSession = Dep
         "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],
-        "habits": [serialize(x, ["id", "name", "kind", "target", "max_value", "schedule_type", "weekdays", "month_days", "interval_days", "start_date", "archived_at"]) for x in habits],
+        "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],
     }
 
@@ -835,6 +865,7 @@ async def restore_json(payload: dict, mode: str = Query("merge", pattern="^(merg
             interval_days=raw.get("interval_days"),
             start_date=date.fromisoformat(raw["start_date"]),
             archived_at=datetime.fromisoformat(raw["archived_at"]) if raw.get("archived_at") else None,
+            position=raw.get("position", 0),
         )
         db.add(row)
     existing_countdown_ids = set((await db.scalars(select(Countdown.id).where(Countdown.user_id == user.id))).all())

backend/schemas.py

@@ -96,6 +96,16 @@ class TaskUpdate(BaseModel):
         return self
 
 
+class TaskReorder(BaseModel):
+    task_ids: list[UUID] = Field(min_length=1)
+
+    @model_validator(mode="after")
+    def unique_ids(self):
+        if len(self.task_ids) != len(set(self.task_ids)):
+            raise ValueError("task_ids must be unique")
+        return self
+
+
 class TaskOut(BaseModel):
     model_config = ConfigDict(from_attributes=True)
     id: UUID