"""子表按行同步：更新原行、新增缺行、只软删去掉的行。"""

import unittest
from datetime import datetime

from sqlalchemy import Column, DateTime, Integer, SmallInteger, String, create_engine
from sqlalchemy.orm import sessionmaker

from app.core.database import Base
from app.crud.child_row_sync import sync_child_rows


class DemoChild(Base):
    __tablename__ = "demo_child_row"

    id = Column(String(64), primary_key=True)
    parent_id = Column(String(64), nullable=False)
    tenant_no = Column(String(64), nullable=False)
    item_code = Column(String(64))
    item_name = Column(String(128))
    order_num = Column(Integer)
    create_time = Column(DateTime)
    update_by = Column(String(64))
    update_time = Column(DateTime)
    del_flag = Column(SmallInteger, nullable=False, default=0)


def _session():
    engine = create_engine("sqlite://")
    DemoChild.__table__.create(bind=engine)
    return sessionmaker(bind=engine)()


def _row(**kwargs):
    now = datetime(2026, 10, 27, 9, 0, 0)
    data = dict(
        parent_id="parent-1",
        tenant_no="tenant-a",
        item_code="R-1",
        item_name="试剂",
        order_num=0,
        create_time=now,
        update_time=now,
        del_flag=0,
    )
    data.update(kwargs)
    return DemoChild(**data)


def _sync(db, items):
    now = datetime(2026, 10, 27, 10, 0, 0)

    def build_row(row_id):
        return DemoChild(
            id=row_id,
            parent_id="parent-1",
            tenant_no="tenant-a",
            create_time=now,
        )

    def apply_row(row, item, idx, _now):
        row.item_code = item.get("item_code")
        row.item_name = item.get("item_name")
        row.order_num = idx

    return sync_child_rows(
        db,
        DemoChild,
        parent_attr="parent_id",
        parent_id="parent-1",
        tenant_no="tenant-a",
        items=items,
        user_id="user-1",
        now=now,
        build_row=build_row,
        apply_fields=apply_row,
        natural_key=lambda item: (item.get("item_code") or "").strip(),
        row_natural_key=lambda row: (row.item_code or "").strip(),
    )


class TestChildRowSync(unittest.TestCase):
    def test_id_keeps_row_when_fields_change(self):
        db = _session()
        db.add(_row(id="row-keep", item_name="旧名称"))
        db.commit()

        saved = _sync(db, [{"id": "row-keep", "item_code": "R-2", "item_name": "新名称"}])

        self.assertEqual(saved[0].id, "row-keep")
        self.assertEqual(saved[0].item_name, "新名称")
        self.assertEqual(db.query(DemoChild).filter_by(del_flag=0).count(), 1)

    def test_natural_key_keeps_id_when_payload_omits_id(self):
        db = _session()
        db.add(_row(id="row-keep", item_code="R-1"))
        db.commit()

        saved = _sync(db, [{"item_code": "R-1", "item_name": "改名"}])

        self.assertEqual([row.id for row in saved], ["row-keep"])
        self.assertEqual(saved[0].item_name, "改名")

    def test_insert_update_and_soft_delete_removed(self):
        db = _session()
        db.add(_row(id="row-keep", item_code="R-1"))
        db.add(_row(id="row-drop", item_code="R-9", item_name="去掉"))
        db.commit()

        saved = _sync(
            db,
            [
                {"id": "row-keep", "item_code": "R-1", "item_name": "留下"},
                {"item_code": "R-NEW", "item_name": "新增"},
            ],
        )

        self.assertEqual(saved[0].id, "row-keep")
        self.assertNotEqual(saved[1].id, "row-drop")
        rows = {row.id: row for row in db.query(DemoChild).all()}
        self.assertEqual(rows["row-keep"].del_flag, 0)
        self.assertEqual(rows["row-drop"].del_flag, 1)
        self.assertEqual(rows[saved[1].id].del_flag, 0)

    def test_id_from_another_parent_is_rejected(self):
        db = _session()
        db.add(_row(id="row-other", parent_id="parent-2"))
        db.commit()

        with self.assertRaises(ValueError):
            _sync(db, [{"id": "row-other", "item_code": "R-1", "item_name": "占用"}])
        other = db.query(DemoChild).filter_by(id="row-other").one()
        self.assertEqual(other.parent_id, "parent-2")
        self.assertEqual(other.del_flag, 0)

    def test_readded_business_key_restores_deleted_row(self):
        db = _session()
        db.add(_row(id="row-old", item_code="R-1", del_flag=1))
        db.commit()
        now = datetime(2026, 10, 27, 10, 0, 0)

        def build_row(row_id):
            return DemoChild(
                id=row_id,
                parent_id="parent-1",
                tenant_no="tenant-a",
                create_time=now,
            )

        def apply_row(row, item, idx, _now):
            row.item_code = item.get("item_code")
            row.item_name = item.get("item_name")
            row.order_num = idx

        saved = sync_child_rows(
            db,
            DemoChild,
            parent_attr="parent_id",
            parent_id="parent-1",
            tenant_no="tenant-a",
            items=[{"item_code": "R-1", "item_name": "恢复"}],
            user_id="user-1",
            now=now,
            build_row=build_row,
            apply_fields=apply_row,
            natural_key=lambda item: (item.get("item_code") or "").strip(),
            row_natural_key=lambda row: (row.item_code or "").strip(),
            reuse_deleted=True,
        )
        db.commit()

        self.assertEqual(saved[0].id, "row-old")
        self.assertEqual(saved[0].del_flag, 0)
        self.assertEqual(db.query(DemoChild).count(), 1)

    def test_removing_live_row_clears_older_tombstone(self):
        db = _session()
        db.add(_row(id="row-live", item_code="R-1"))
        db.add(_row(id="row-tomb", item_code="R-1", del_flag=1))
        db.commit()
        now = datetime(2026, 10, 27, 10, 0, 0)

        sync_child_rows(
            db,
            DemoChild,
            parent_attr="parent_id",
            parent_id="parent-1",
            tenant_no="tenant-a",
            items=[],
            user_id="user-1",
            now=now,
            build_row=lambda row_id: DemoChild(
                id=row_id, parent_id="parent-1", tenant_no="tenant-a", create_time=now
            ),
            apply_fields=lambda row, item, idx, _now: None,
            natural_key=lambda item: (item.get("item_code") or "").strip(),
            row_natural_key=lambda row: (row.item_code or "").strip(),
            reuse_deleted=True,
        )
        db.commit()

        self.assertIsNone(db.query(DemoChild).filter_by(id="row-tomb").first())
        live = db.query(DemoChild).filter_by(id="row-live").one()
        self.assertEqual(live.del_flag, 1)


if __name__ == "__main__":
    unittest.main()